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Sleep Disorders

Sleep Disorders

Definition

Sleep disorders are a group of syndromes characterized by disturbance in the patient's amount of sleep, quality or timing of sleep, or in behaviors or physiological conditions associated with sleep. There are about 70 different sleep disorders. To qualify for the diagnosis of sleep disorder, the condition must be a persistent problem, cause the patient significant emotional distress, and interfere with his or her social or occupational functioning.

Although sleep is a basic behavior in animals as well as humans, researchers still do not completely understand all of its functions in maintaining health. In the past 30 years, however, laboratory studies on human volunteers have yielded new information about the different types of sleep. Researchers have learned about the cyclical patterns of different types of sleep and their relationships to breathing, heart rate, brain waves, and other physical functions. These measurements are obtained by a technique called polysomnography.

There are five stages of human sleep. Four stages have non-rapid eye movement (NREM) sleep, with unique brain wave patterns and physical changes occurring. Dreaming occurs in the fifth stage, during rapid eye movement (REM) sleep.

  • Stage 1 NREM sleep. This stage occurs while a person is falling asleep. It represents about 5% of a normal adult's sleep time.
  • Stage 2 NREM sleep. In this stage, (the beginning of "true" sleep), the person's electroencephalogram (EEG) will show distinctive wave forms called sleep spindles and K complexes. About 50% of sleep time is stage 2 REM sleep.
  • Stages 3 and 4 NREM sleep. Also called delta or slow wave sleep, these are the deepest levels of human sleep and represent 10-20% of sleep time. They usually occur during the first 30-50% of the sleeping period.
  • REM sleep. REM sleep accounts for 20-25% of total sleep time. It usually begins about 90 minutes after the person falls asleep, an important measure called REM latency. It alternates with NREM sleep about every hour and a half throughout the night. REM periods increase in length over the course of the night.

Sleep cycles vary with a person's age. Children and adolescents have longer periods of stage 3 and stage 4 NREM sleep than do middle aged or elderly adults. Because of this difference, the doctor will need to take a patient's age into account when evaluating a sleep disorder. Total REM sleep also declines with age.

The average length of nighttime sleep varies among people. Most people sleep between seven and nine hours a night. This population average appears to be constant throughout the world. In temperate climates, however, people often notice that sleep time varies with the seasons. It is not unusual for people in North America and Europe to sleep about 40 minutes longer per night during the winter.

Description

Sleep disorders are classified based on what causes them. Primary sleep disorders are distinguished from those that are not caused by other mental disorders, prescription medications, substance abuse, or medical conditions. The two major categories of primary sleep disorders are the dyssomnias and the parasomnias.

Dyssomnias

Dyssomnias are primary sleep disorders in which the patient suffers from changes in the amount, restfulness, and timing of sleep. The most important dyssomnia is primary insomnia, which is defined as difficulty in falling asleep or remaining asleep that lasts for at least one month. It is estimated that 35% of adults in the United States experience insomnia during any given year, but the number of these adults who are experiencing true primary insomnia is unknown. Primary insomnia can be caused by a traumatic event related to sleep or bedtime, and it is often associated with increased physical or psychological arousal at night. People who experience primary insomnia are often anxious about not being able to sleep. The person may then associate all sleep-related things (their bed, bedtime, etc.) with frustration, making the problem worse. The person then becomes more stressed about not sleeping. Primary insomnia usually begins when the person is a young adult or in middle age.

Hypersomnia is a condition marked by excessive sleepiness during normal waking hours. The patient has either lengthy episodes of daytime sleep or episodes of daytime sleep on a daily basis even though he or she is sleeping normally at night. In some cases, patients with primary hypersomnia have difficulty waking in the morning and may appear confused or angry. This condition is sometimes called sleep drunkenness and is more common in males. The number of people with primary hypersomnia is unknown, although 5-10% of patients in sleep disorder clinics have the disorder. Primary hypersomnia usually affects young adults between the ages of 15 and 30.

Nocturnal myoclonus and restless legs syndrome (RLS) can cause either insomnia or hypersomnia in adults. Patients with nocturnal myoclonus wake up because of cramps or twitches in the calves. These patients feel sleepy the next day. Nocturnal myoclonus is sometimes called periodic limb movement disorder (PLMD). RLS patients have a crawly or aching feeling in their calves that can be relieved by moving or rubbing the legs. RLS often prevents the patient from falling asleep until the early hours of the morning, when the condition is less intense.

Kleine-Levin syndrome is a recurrent form of hypersomnia that affects a person three or four times a year. Doctors do not know the cause of this syndrome. It is marked by two to three days of sleeping 18-20 hours per day, hypersexual behavior, compulsive eating, and irritability. Men are three times more likely than women to have the syndrome. Currently, there is no cure for this disorder.

Narcolepsy is a dyssomnia characterized by recurrent "sleep attacks" that the patient cannot fight. The sleep attacks are about 10-20 minutes long. The patient feels refreshed by the sleep, but typically feels sleepy again several hours later. Narcolepsy has three major symptoms in addition to sleep attacks: cataplexy, hallucinations, and sleep paralysis. Cataplexy is the sudden loss of muscle tone and stability ("drop attacks"). Hallucinations may occur just before falling asleep (hypnagogic) or right after waking up (hypnopompic) and are associated with an episode of REM sleep. Sleep paralysis occurs during the transition from being asleep to waking up. About 40% of patients with narcolepsy have or have had another mental disorder. Although narcolepsy is often regarded as an adult disorder, it has been reported in children as young as three years old. Almost 18% of patients with narcolepsy are 10 years old or younger. It is estimated that 0.02-0.16% of the general population suffer from narcolepsy. Men and women are equally affected.

Breathing-related sleep disorders are syndromes in which the patient's sleep is interrupted by problems with his or her breathing. There are three types of breathing-related sleep disorders:

  • Obstructive sleep apnea syndrome. This is the most common form of breathing-related sleep disorder, marked by episodes of blockage in the upper airway during sleep. It is found primarily in obese people. Patients with this disorder typically alternate between periods of snoring or gasping (when their airway is partly open) and periods of silence (when their airway is blocked). Very loud snoring is a clue to this disorder.
  • Central sleep apnea syndrome. This disorder is primarily found in elderly patients with heart or neurological conditions that affect their ability to breathe properly. It is not associated with airway blockage and may be related to brain disease.
  • Central alveolar hypoventilation syndrome. This disorder is found most often in extremely obese people. The patient's airway is not blocked, but his or her blood oxygen level is too low.
  • Mixed-type sleep apnea syndrome. This disorder combines symptoms of both obstructive and central sleep apnea.

Circadian rhythm sleep disorders are dyssomnias resulting from a discrepancy between the person's daily sleep/wake patterns and demands of social activities, shift work, or travel. The term circadian comes from a Latin word meaning daily. There are three circadian rhythm sleep disorders. Delayed sleep phase type is characterized by going to bed and arising later than most people. Jet lag type is caused by travel to a new time zone. Shift work type is caused by the schedule of a person's job. People who are ordinarily early risers appear to be more vulnerable to jet lag and shift work-related circadian rhythm disorders than people who are "night owls." There are some patients who do not fit the pattern of these three disorders and appear to be the opposite of the delayed sleep phase type. These patients have an advanced sleep phase pattern and cannot stay awake in the evening, but wake up on their own in the early morning.

PARASOMNIAS. Parasomnias are primary sleep disorders in which the patient's behavior is affected by specific sleep stages or transitions between sleeping and waking. They are sometimes described as disorders of physiological arousal during sleep.

Nightmare disorder is a parasomnia in which the patient is repeatedly awakened from sleep by frightening dreams and is fully alert on awakening. The actual rate of occurrence of nightmare disorder is unknown. Approximately 10-50% of children between three and five years old have nightmares. They occur during REM sleep, usually in the second half of the night. The child is usually able to remember the content of the nightmare and may be afraid to go back to sleep. More females than males have this disorder, but it is not known whether the sex difference reflects a difference in occurrence or a difference in reporting. Nightmare disorder is most likely to occur in children or adults under severe or traumatic stress.

Sleep terror disorder is a parasomnia in which the patient awakens screaming or crying. The patient also has physical signs of arousal, like sweating, shaking, etc. It is sometimes referred to as pavor nocturnus. Unlike nightmares, sleep terrors typically occur in stage 3 or stage 4 NREM sleep during the first third of the night. The patient may be confused or disoriented for several minutes and cannot recall the content of the dream. He or she may fall asleep again and not remember the episode the next morning. Sleep terror disorder is most common in children four to 12 years old and is outgrown in adolescence. It affects about 3% of children. Fewer than 1% of adults have the disorder. In adults, it usually begins between the ages of 20 and 30. In children, more males than females have the disorder. In adults, men and women are equally affected.

Sleepwalking disorder, which is sometimes called somnambulism, occurs when the patient is capable of complex movements during sleep, including walking. Like sleep terror disorder, sleepwalking occurs during stage 3 and stage 4 NREM sleep during the first part of the night. If the patient is awakened during a sleepwalking episode, he or she may be disoriented and have no memory of the behavior. In addition to walking around, patients with sleepwalking disorder have been reported to eat, use the bathroom, unlock doors, or talk to others. It is estimated that 10-30% of children have at least one episode of sleepwalking. However, only 1-5% meet the criteria for sleepwalking disorder. The disorder is most common in children eight to 12 years old. It is unusual for sleepwalking to occur for the first time in adults.

Unlike sleepwalking, REM sleep behavior disorder occurs later in the night and the patient can remember what they were dreaming. The physical activities of the patient are often violent.

Sleep disorders related to other conditions

In addition to the primary sleep disorders, there are three categories of sleep disorders that are caused by or related to substance use or other physical or mental disorders.

SLEEP DISORDERS RELATED TO MENTAL DISORDERS. Many mental disorders, especially depression or one of the anxiety disorders, can cause sleep disturbances. Psychiatric disorders are the most common cause of chronic insomnia.

SLEEP DISORDERS DUE TO MEDICAL CONDITIONS. Some patients with chronic neurological conditions like Parkinson's disease or Huntington's disease may develop sleep disorders. Sleep disorders have also been associated with viral encephalitis, brain disease, and hypo- or hyperthyroidism.

SUBSTANCE-INDUCED SLEEP DISORDERS. The use of drugs, alcohol, and caffeine frequently produces disturbances in sleep patterns. Alcohol abuse is associated with insomnia. The person may initially feel sleepy after drinking, but wakes up or sleeps fitfully during the second half of the night. Alcohol can also increase the severity of breathing-related sleep disorders. With amphetamines or cocaine, the patient typically suffers from insomnia during drug use and hypersomnia during drug withdrawal. Opioids usually make short-term users sleepy. However, long-term users develop tolerance and may suffer from insomnia.

In addition to alcohol and drugs that are abused, a variety of prescription medications can affect sleep patterns. These medications include antihistamines, corticosteroids, asthma medicines, and drugs that affect the central nervous system.

Sleep disorders in children and adolescents

Pediatricians estimate that 20-30% of children have difficulties with sleep that are serious enough to disturb their families. Although sleepwalking and night terror disorder occur more frequently in children than in adults, children can also suffer from narcolepsy and sleep apnea syndrome.

Causes and symptoms

The causes of sleep disorders have already been discussed with respect to the classification of these disorders.

The most important symptoms of sleep disorders are insomnia and sleepiness during waking hours. Insomnia is by far the more common of the two symptoms. It covers a number of different patterns of sleep disturbance. These patterns include inability to fall asleep at bedtime, repeated awakening during the night, and/or inability to go back to sleep once awakened.

Diagnosis

Diagnosis of sleep disorders usually requires a psychological history as well as a medical history. With the exception of sleep apnea syndromes, physical examinations are not usually revealing. The patient's sex and age are useful starting points in assessing the problem. The doctor may also talk to other family members in order to obtain information about the patient's symptoms. The family's observations are particularly important to evaluate sleepwalking, kicking in bed, snoring loudly, or other behaviors that the patient cannot remember.

Sleep logs

Many doctors ask patients to keep a sleep diary or sleep log for a minimum of one to two weeks in order to evaluate the severity and characteristics of the sleep disturbance. The patient records medications taken as well as the length of time spent in bed, the quality of the sleep, and similar information. Some sleep logs are designed to indicate circadian sleep patterns as well as simple duration or restfulness of sleep.

Psychological testing

The doctor may use psychological tests or inventories to evaluate insomnia because it is frequently associated with mood or affective disorders. The Minnesota Multiphasic Personality Inventory (MMPI), the Millon Clinical Multiaxial Inventory (MCMI), the Beck Depression Inventory, and the Zung Depression Scale are the tests most commonly used in evaluating this symptom.

SELF-REPORT TESTS. The Epworth Sleepiness Scale, a self-rating form recently developed in Australia, consists of eight questions used to assess daytime sleepiness. Scores range from 0-24, with scores higher than 16 indicating severe daytime sleepiness.

Laboratory studies

If the doctor is considering breathing-related sleep disorders, myoclonus, or narcolepsy as possible diagnoses, he or she may ask the patient to be tested in a sleep laboratory or at home with portable instruments.

POLYSOMNOGRAPHY. Polysomnography can be used to help diagnose sleep disorders as well as conduct research into sleep. In some cases the patient is tested in a special sleep laboratory. The advantage of this testing is the availability and expertise of trained technologists, but it is expensive. As of 2001, however, portable equipment is available for home recording of certain specific physiological functions.

MULTIPLE SLEEP LATENCY TEST (MSLT). The multiple sleep latency test (MSLT) is frequently used to measure the severity of the patient's daytime sleepiness. The test measures sleep latency (the speed with which the patient falls asleep) during a series of planned naps during the day. The test also measures the amount of REM sleep that occurs. Two or more episodes of REM sleep under these conditions indicates narcolepsy. This test can also be used to help diagnose primary hypersomnia.

REPEATED TEST OF SUSTAINED WAKEFULNESS (RTSW). The repeated test of sustained wakefulness (RTSW) is a test that measures sleep latency by challenging the patient's ability to stay awake. In the RTSW, the patient is placed in a quiet room with dim lighting and is asked to stay awake. As with the MSLT, the testing pattern is repeated at intervals during the day.

Treatment

Treatment for a sleep disorder depends on what is causing the disorder. For example, if major depression is the cause of insomnia, then treatment of the depression with antidepressants should resolve the insomnia.

Medications

Sedative or hypnotic medications are generally recommended only for insomnia related to a temporary stress (like surgery or grief) because of the potential for addiction or overdose. Trazodone, a sedating antidepressant, is often used for chronic insomnia that does not respond to other treatments. Sleep medications may also cause problems for elderly patients because of possible interactions with their other prescription medications. Among the safer hypnotic agents are lorazepam, temazepam, and zolpidem. Chloral hydrate is often preferred for short-term treatment in elderly patients because of its mildness. Short-term treatment is recommended because this drug may be habit forming.

Narcolepsy is treated with stimulants such as dextroamphetamine sulfate or methylphenidate. Nocturnal myoclonus has been successfully treated with clonazepam.

Children with sleep terror disorder or sleepwalking are usually treated with benzodiazepines because this type of medication suppresses stage 3 and stage 4 NREM sleep.

Psychotherapy

Psychotherapy is recommended for patients with sleep disorders associated with other mental disorders. In many cases the patient's scores on the Beck or Zung inventories will suggest the appropriate direction of treatment.

Sleep education

"Sleep hygiene" or sleep education for sleep disorders often includes instructing the patient in methods to enhance sleep. Patients are advised to:

  • wait until he or she is sleepy before going to bed
  • avoid using the bedroom for work, reading, or watching television
  • get up at the same time every morning no matter how much or how little he or she slept
  • avoid smoking and avoid drinking liquids with caffeine
  • get some physical exercise early in the day every day
  • limit fluid intake after dinner; in particular, avoid alcohol because it frequently causes interrupted sleep
  • learn to meditate or practice relaxation techniques
  • avoid tossing and turning in bed; instead, he or she should get up and listen to relaxing music or read

Lifestyle changes

Patients with sleep apnea or hypopnea are encouraged to stop smoking, avoid alcohol or drugs of abuse, and lose weight in order to improve the stability of the upper airway.

In some cases, patients with sleep disorders related to jet lag or shift work may need to change employment or travel patterns. Patients may need to avoid rapid changes in shifts at work.

Children with nightmare disorder may benefit from limits on television or movies. Violent scenes or frightening science fiction stories appear to influence the frequency and intensity of children's nightmares.

Surgery

Although making a surgical opening into the windpipe (a tracheostomy) for sleep apnea or hypopnea in adults is a treatment of last resort, it is occasionally performed if the patient's disorder is life threatening and cannot be treated by other methods. In children and adolescents, surgical removal of the tonsils and adenoids is a fairly common and successful treatment for sleep apnea. Most sleep apnea patients are treated with continuous positive airway pressure (CPAP). Sometimes an oral prosthesis is used for mild sleep apnea.

Alternative treatment

Some alternative approaches may be effective in treating insomnia caused by anxiety or emotional stress. Meditation practice, breathing exercises, and yoga can break the vicious cycle of sleeplessness, worry about inability to sleep, and further sleeplessness for some people. Yoga can help some people to relax muscular tension in a direct fashion. The breathing exercises and meditation can keep some patients from obsessing about sleep.

Homeopathic practitioners recommend that people with chronic insomnia see a professional homeopath. They do, however, prescribe specific remedies for at-home treatment of temporary insomnia: Nux vomica for alcohol or substance-related insomnia, Ignatia for insomnia caused by grief, Arsenicum for insomnia caused by fear or anxiety, and Passiflora for insomnia related to mental stress.

Melatonin has also been used as an alternative treatment for sleep disorders. Melatonin is produced in the body by the pineal gland at the base of the brain. This substance is thought to be related to the body's circadian rhythms.

KEY TERMS

Apnea The temporary absence of breathing. Sleep apnea consists of repeated episodes of temporary suspension of breathing during sleep.

Cataplexy Sudden loss of muscle tone (often causing a person to fall), usually triggered by intense emotion. It is regarded as a diagnostic sign of narcolepsy.

Circadian rhythm Any body rhythm that recurs in 24-hour cycles. The sleep-wake cycle is an example of a circadian rhythm.

Dyssomnia A primary sleep disorder in which the patient suffers from changes in the quantity, quality, or timing of sleep.

Electroencephalogram (EEG) The record obtained by a device that measures electrical impulses in the brain.

Hypersomnia An abnormal increase of 25% or more in time spent sleeping. Patients usually have excessive daytime sleepiness.

Hypnotic A medication that makes a person sleep.

Hypopnea Shallow or excessively slow breathing usually caused by partial closure of the upper airway during sleep, leading to disruption of sleep.

Insomnia Difficulty in falling asleep or remaining asleep.

Jet lag A temporary disruption of the body's sleep-wake rhythm following high-speed air travel across several time zones. Jet lag is most severe in people who have crossed eight or more time zones in 24 hours.

Kleine-Levin syndrome A disorder that occurs primarily in young males, three or four times a year. The syndrome is marked by episodes of hypersomnia, hypersexual behavior, and excessive eating.

Narcolepsy A life-long sleep disorder marked by four symptoms: sudden brief sleep attacks, cataplexy, temporary paralysis, and hallucinations. The hallucinations are associated with falling asleep or the transition from sleeping to waking.

Nocturnal myoclonus A disorder in which the patient is awakened repeatedly during the night by cramps or twitches in the calf muscles. Nocturnal myoclonus is sometimes called periodic limb movement disorder (PLMD).

Non-rapid eye movement (NREM) sleep A type of sleep that differs from rapid eye movement (REM) sleep. The four stages of NREM sleep account for 75-80% of total sleeping time.

Parasomnia A primary sleep disorder in which the person's physiology or behaviors are affected by sleep, the sleep stage, or the transition from sleeping to waking.

Pavor nocturnus Another term for sleep terror disorder.

Polysomnography Laboratory measurement of a patient's basic physiological processes during sleep. Polysomnography usually measures eye movement, brain waves, and muscular tension.

Primary sleep disorder A sleep disorder that cannot be attributed to a medical condition, another mental disorder, or prescription medications or other substances.

Rapid eye movement (REM) sleep A phase of sleep during which the person's eyes move rapidly beneath the lids. It accounts for 20-25% of sleep time. Dreaming occurs during REM sleep.

REM latency After a person falls asleep, the amount of time it takes for the first onset of REM sleep.

Restless legs syndrome (RLS) A disorder in which the patient experiences crawling, aching, or other disagreeable sensations in the calves that can be relieved by movement. RLS is a frequent cause of difficulty falling asleep at night.

Sedative A medication given to calm agitated patients; sometimes used as a synonym for hypnotic.

Sleep latency The amount of time that it takes to fall asleep. Sleep latency is measured in minutes and is important in diagnosing depression.

Somnambulism Another term for sleepwalking.

Practitioners of Chinese medicine usually treat insomnia as a symptom of excess yang energy. Cinnabar is recommended for chronic nightmares. Either magnetic magnetite or "dragon bones" is recommended for insomnia associated with hysteria or fear. If the insomnia appears to be associated with excess yang energy arising from the liver, the practitioner will give the patient oyster shells. Acupuncture treatments can help bring about balance and facilitate sleep.

Dietary changes like eliminating stimulant foods (coffee, cola, chocolate) and late-night meals or snacks can be effective in treating some sleep disorders. Nutritional supplementation with magnesium, as well as botanical medicines that calm the nervous system, can also be helpful. Among the botanical remedies that may be effective for sleep disorders are valerian (Valeriana officinalis ), passionflower (Passiflora incarnata ), and skullcap (Scutellaria lateriflora ).

Prognosis

The prognosis depends on the specific disorder. Children usually outgrow sleep disorders. Patients with Kleine-Levin syndrome usually get better around age 40. Narcolepsy is a life-long disorder. The prognosis for sleep disorders related to other conditions depends on successful treatment of the substance abuse, medical condition, or other mental disorder. The prognosis for primary sleep disorders is affected by many things, including the patient's age, sex, occupation, personality characteristics, family circumstances, neighborhood environment, and similar factors.

Resources

BOOKS

Moe, Paul G., and Alan R. Seay. "Neurologic & Muscular Disorders: Sleep Disorders." In Current Pediatric Diagnosis & Treatment, edited by William W. Hay Jr., et al. Stamford: Appleton & Lange, 1997.

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Sleep Disorders

Sleep disorders

Definition

Sleep disorders are a group of syndromes characterized by disturbance in the individual's amount of sleep, quality or timing of sleep, or in behaviors or physiological conditions associated with sleep.

Description

Although sleep is a basic behavior in animals as well as humans, researchers still do not completely understand all of its functions in maintaining health. Since 1975, however, laboratory studies on human volunteers have yielded information about the different types of sleep. Researchers have learned about the cyclical patterns of different types of sleep and their relationships to breathing, heart rate, brain waves, and other physical functions. These measurements are obtained by a technique called polysomnography. There are about 70 different sleep disorders. To qualify for the diagnosis of sleep disorder, the condition must be a persistent problem, cause the patient significant emotional distress, and interfere with his or her social, academic, or occupational functioning.

There are five stages of human sleep. Four stages have non-rapid eye movement (NREM) sleep, with unique brain wave patterns and physical changes occurring. Dreaming occurs in the fifth stage, during rapid eye movement (REM) sleep.

  • Stage one NREM sleep. This stage occurs while a child is falling asleep. It represents about 5 percent of sleep time.
  • Stage two NREM sleep. In this stage, (the beginning of "true" sleep), the child's electroencephalogram (EEG) will show distinctive waveforms called sleep spindles and K complexes. About 50 percent of sleep time is stage two NREM sleep.
  • Stages three and four NREM sleep. Also called delta or slow wave sleep, these are the deepest levels of human sleep and represent 10 to 20 percent of sleep time. They usually occur during the first 30 to 50 percent of the sleeping period.
  • REM sleep. REM sleep accounts for 20 to 25 percent of total sleep time. It usually begins about 90 minutes after the child falls asleep. It alternates with NREM sleep about every hour and a half throughout the night. REM periods increase in length over the course of the night.

Sleep cycles vary with a person's age. Children and adolescents have longer periods of stage three and stage four NREM sleep than do middle aged or elderly adults. Because of this difference, the doctor needs to consider the individual's age when evaluating a sleep disorder. Total REM sleep also declines with age.

The average length of nighttime sleep varies among individuals. Most people sleep between seven and nine hours a night. This population average appears to be constant throughout the world. In temperate climates, however, people often notice that sleep time varies with the seasons. It is not unusual for people in North America and Europe to sleep about 40 minutes longer per night during the winter. Infants can regularly sleep up to 16 hours a day. The total amount of sleep declines as the infant gets older. Teenagers may actually need more sleep than slightly younger children and often sleep nine or more hours a day.

Sleep disorders are classified based on what causes them. Primary sleep disorders are distinguished as those that are not caused by other mental disorders, prescription medications, substance abuse, or medical conditions. The two major categories of primary sleep disorders are the dyssomnias and the parasomnias.

Dyssomnias

Dyssomnias are primary sleep disorders in which the patient suffers from changes in the amount, restfulness, and timing of sleep. The most important dyssomnia is primary insomnia, which is defined as difficulty that lasts for at least one month in falling asleep or remaining asleep. Primary insomnia can be caused by many things, including a traumatic event related to sleep or bedtime, and it is often associated with increased physical or psychological arousal at night. Children who experience primary insomnia may develop anxiety related to not being able to sleep. The child may come to associate all sleep-related things (their bed, bedtime, etc.) with frustration, making the problem worse. The child may then becomes more stressed about not sleeping.

Hypersomnia is a condition marked by excessive sleepiness during normal waking hours. The individual has either lengthy episodes of daytime sleep or episodes of daytime sleep on a daily basis even though he or she is sleeping normally at night. In some cases, people with primary hypersomnia have difficulty waking in the morning and may appear confused or angry. This condition is sometimes called sleep drunkenness and is more common in males.

The number of people with primary hypersomnia is unknown, although 5 to 10 percent of patients in sleep disorder clinics have the disorder. Primary hypersomnia usually affects young adults between the ages of 15 and 30.

Kleine-Levin syndrome is a recurrent form of hypersomnia that usually starts in late teen years. Doctors do not know the cause of this syndrome. It is marked by excessive drowsiness and for short spells, maybe two to three days, the person sleeps 18 to 20 hours per day, overeats, and is highly irritable. Males are three or four times more likely than females to have the syndrome.

PARASOMNIAS Parasomnias are primary sleep disorders in which the individual's behavior is affected by specific sleep stages or transitions between sleeping and waking. They are sometimes described as disorders of physiological arousal during sleep.

Nightmare disorder is a parasomnia in which the child is repeatedly awakened from sleep by frightening dreams and is fully alert on awakening. The actual rate of occurrence of nightmare disorder is unknown. Approximately 10 to 50 percent of children between three and five years old have nightmares , as do many older children. The nightmares occur during REM sleep, usually in the second half of the night. The child is usually able to remember the content of the nightmare and may be afraid to go back to sleep. More females than males have this disorder, but it is not known whether the sex difference reflects a difference in occurrence or a difference in reporting. Nightmare disorder is most likely to occur in children under severe or traumatic stress.

Sleep terror disorder is a parasomnia in which the child awakens screaming or crying. The child also has physical signs of arousal, like sweating and shaking. Sleep terror is sometimes referred to as pavor nocturnus. Unlike nightmares, sleep terrors typically occur in stage three or stage four NREM sleep during the first third of the night. The child may be confused or disoriented for several minutes and cannot recall the content of the dream. He or she may fall asleep again and not remember the episode the next morning. Sleep terror disorder is most common in children four to 12 years old and is usually outgrown in adolescence . It affects about 3 percent of children. In children, more males than females have the disorder.

Sleepwalking disorder, which is sometimes called somnambulism , occurs when the child is capable of complex movements during sleep, including walking. Like sleep terror disorder, sleepwalking occurs during stage three and stage four NREM sleep during the first part of the night. If the child is awakened during a sleepwalking episode, he or she may be disoriented and have no memory of the behavior. In addition to walking around, individuals with sleepwalking disorder have been reported to eat, use the bathroom, unlock doors, or talk to others. It is estimated that 10 to 30 percent of children have at least one episode of sleepwalking. However, only 1 to 5 percent meet the criteria for sleepwalking disorder. The disorder is most common in children eight to 12 years old.

Demographics

In the United States, 20 to 25 percent of children have some kind of sleep problem. Nightmares are believed to occur in about 30 percent of children, usually in younger children. Sleepwalking occurs more than once in about 25 to 30 percent of children. The most common age group to experience sleepwalking is children under 10. Insomnia is reported to occur in approximately 23 percent of children. Many other sleep disorders occur less frequently but are still a problem for many children.

Causes and symptoms

The causes of sleep disorders vary depending on the disorder. Many times, stress, anxiety, or other factors are found to be the cause. Often the underlying cause of the sleep disorder is never found.

The most important symptoms of sleep disorders are insomnia and sleepiness during waking hours. Insomnia is by far the more common of the two symptoms. It covers a number of different patterns of sleep disturbance. These patterns include inability to fall asleep at bedtime, repeated awakening during the night, and/or inability to go back to sleep once awakened.

When to call the doctor

If a child does not seem to be getting enough sleep at night or the child wakes frequently or seems tired frequently during the day, it may be helpful to consult a doctor.

Diagnosis

Diagnosis of sleep disorders usually requires a psychological history as well as a medical history. Physical examinations are not usually revealing. The patient's sex and age are useful starting points in assessing the problem. The doctor may also talk to other family members in order to obtain information about the patient's symptoms. The family's observations are particularly important for evaluating sleepwalking, kicking in bed, snoring loudly, or other behaviors that the patient cannot remember.

Psychological testing

The doctor may use psychological tests or inventories to evaluate insomnia because it is frequently associated with mood or affective disorders. The Minnesota Multiphasic Personality Inventory (MMPI), the Millon Clinical Multiaxial Inventory (MCMI), the Beck Depression Inventory, and the Zung Depression Scale are the tests most commonly used in evaluating this symptom.

Laboratory studies

If the doctor is considering breathing-related sleep disorders, myoclonus, or narcolepsy as possible diagnoses, he or she may ask the patient to be tested in a sleep laboratory or at home with portable instruments.

POLYSOMNOGRAPHY Polysomnography can be used to help diagnose sleep disorders as well as conduct research into sleep. In some cases the patient is tested in a special sleep laboratory. The advantage of this testing is the availability and expertise of trained technologists, but it is expensive. Since 2001, however, portable equipment is available for home recording of certain specific physiological functions.

MULTIPLE SLEEP LATENCY TEST (MSLT) The multiple sleep latency test (MSLT) is frequently used to measure the severity of the patient's daytime sleepiness. The test measures sleep latency (the speed with which the patient falls asleep) during a series of planned naps during the day. The test also measures the amount of REM sleep that occurs. Two or more episodes of REM sleep under these conditions indicates narcolepsy. This test can also be used to help diagnose primary hypersomnia.

REPEATED TEST OF SUSTAINED WAKEFULNESS (RTSW) The repeated test of sustained wakefulness (RTSW) measures sleep latency by challenging the patient's ability to stay awake. In the RTSW, the patient is placed in a quiet room with dim lighting and is asked to stay awake. As with the MSLT, the testing pattern is repeated at intervals during the day.

Treatment

Treatment for a sleep disorder depends on what is causing the disorder. For example, if major depression is the cause of insomnia, then treatment of the depression with antidepressants or psychological counseling should resolve the insomnia. The use of antidepressants in minors is a matter of debate. In October 2003, the United States Food and Drug Administration issued an advisory indicating that children being treated with selective serotonin re-uptake inhibitor antidepressants (SSRIs) for major depressive illness may be at higher risk for committing suicide . A similar warning was issued in the United Kingdom. Parents and physicians must weigh the benefits and risks of prescribing these medications for children on an individual basis.

Medications

Medications for sleep disorders are generally not recommended for use by children. In most cases medications are the treatment of last resort. If children with sleep terror disorder or sleepwalking are treated with medication, then they may be given benzodiazepines because this type of medication suppresses stage three and stage four NREM sleep.

Psychotherapy

Psychotherapy is recommended for patients with sleep disorders associated with other mental disorders. In many cases the patient's scores on the Beck or Zung inventories will suggest the appropriate direction of treatment.

Sleep preparation

Children with sleep disorders such as insomnia may benefit from a regular pattern of pre-bedtime rituals designed to help the child relax and prepare for bed. Fluid intake should usually be limited in the hours before bed to reduce the need to get out of bed and use the toilet. Children should generally not be given caffeine in the evening, as it may make it harder for them to fall asleep. Children with nightmare disorder may benefit from limits on television or movies. Violent scenes or frightening science fiction stories appear to influence the frequency and intensity of children's nightmares.

Alternative treatment

Some alternative approaches may be effective in treating insomnia caused by anxiety or emotional stress. For some people, meditation practice, breathing exercises, and yoga can break the vicious cycle of sleeplessness, worry about inability to sleep, and further sleeplessness. Yoga can help some people to relax muscular tension in a direct fashion. The breathing exercises and meditation can keep some patients from obsessing about sleep.

Homeopathic practitioners recommend that people with chronic insomnia see a professional homeopath. They do, however, prescribe specific remedies for at-home treatment of temporary insomnia: Nux vomica for alcohol or substance-related insomnia, Ignatia for insomnia caused by grief, Arsenicum for insomnia caused by fear or anxiety, and Passiflora for insomnia related to mental stress.

Melatonin has also been used as an alternative treatment for sleep disorders. Melatonin is produced in the body by the pineal gland at the base of the brain. This substance is thought to be related to the body's circadian rhythms.

Practitioners of traditional Chinese medicine usually treat insomnia as a symptom of excess yang energy. Cinnabar is recommended for chronic nightmares. Either magnetic magnetite or "dragon bones" is recommended for insomnia associated with hysteria or fear. If the insomnia appears to be associated with excess yang energy arising from the liver, the practitioner will give the patient oyster shells. Acupuncture treatments can help bring about balance and facilitate sleep.

Dietary changes such as eliminating stimulant foods (coffee, cola, chocolate) and late-night meals or snacks can be effective in treating some sleep disorders. Nutritional supplementation with magnesium, as well as botanical medicines that calm the nervous system, can also be helpful. Among the botanical remedies that may be effective for sleep disorders are valerian (Valeriana officinalis ), passionflower (Passiflora incarnata ), and skullcap (Scutellaria lateriflora ).

Prognosis

The prognosis depends on the specific disorder. Children usually outgrow sleep disorders. Patients with Kleine-Levin syndrome usually get better around age 40. The prognosis for sleep disorders related to many other

KEY TERMS

Apnea The temporary absence of breathing. Sleep apnea consists of repeated episodes of temporary suspension of breathing during sleep.

Cataplexy A symptom of narcolepsy in which there is a sudden episode of muscle weakness triggered by emotions. The muscle weakness may cause the person's knees to buckle, or the head to drop. In severe cases, the patient may become paralyzed for a few seconds to minutes.

Circadian rhythm Any body rhythm that recurs in 24-hour cycles. The sleep-wake cycle is an example of a circadian rhythm.

Dyssomnia A primary sleep disorder in which the patient suffers from changes in the quantity, quality, or timing of sleep.

Electroencephalogram (EEG) A record of the tiny electrical impulses produced by the brain's activity picked up by electrodes placed on the scalp. By measuring characteristic wave patterns, the EEG can help diagnose certain conditions of the brain.

Hypersomnia An abnormal increase of 25% or more in time spent sleeping. Individuals with hypersomnia usually have excessive daytime sleepiness.

Hypnotics A class of drugs that are used as a sedatives and sleep aids.

Hypopnea Shallow or excessively slow breathing usually caused by partial closure of the upper airway during sleep, leading to disruption of sleep.

Insomnia A sleep disorder characterized by inability either to fall asleep or to stay asleep.

Jet lag A temporary disruption of the body's sleep-wake rhythm following high-speed air travel across several time zones. Jet lag is most severe in people who have crossed eight or more time zones in 24 hours.

Kleine-Levin syndrome A disorder that occurs primarily in young males, three or four times a year. The syndrome is marked by episodes of hypersomnia, hypersexual behavior, and excessive eating.

Narcolepsy A life-long sleep disorder marked by four symptoms: sudden brief sleep attacks, cataplexy (a sudden loss of muscle tone usually lasting up to 30 minutes), temporary paralysis, and hallucinations. The hallucinations are associated with falling asleep or the transition from sleeping to waking.

Nocturnal myoclonus A disorder in which the patient is awakened repeatedly during the night by cramps or twitches in the calf muscles. Also sometimes called periodic limb movement disorder.

Non-rapid eye movement (NREM) sleep A type of sleep that differs from rapid eye movement (REM) sleep. The four stages of NREM sleep account for 7580% of total sleeping time.

Parasomnia A type of sleep disorder characterized by abnormal changes in behavior or body functions during sleep, specific stages of sleep, or the transition from sleeping to waking.

Pavor nocturnus Another name for sleep terror disorder.

Polysomnography An overnight series tests designed to evaluate a patient's basic physiological processes during sleep. Polysomnography generally includes monitoring of the patient's airflow through the nose and mouth, blood pressure, electrocardiographic activity, blood oxygen level, brain wave pattern, eye movement, and the movement of respiratory muscles and limbs

Primary sleep disorder A sleep disorder that cannot be attributed to a medical condition, another mental disorder, or prescription medications or other substances.

Rapid eye movement (REM) latency The amount of time it takes for the first onset of REM sleep after a person falls asleep.

Rapid eye movement (REM) sleep A phase of sleep during which the person's eyes move rapidly beneath the lids. It accounts for 20-25% of sleep time. Dreaming occurs during REM sleep.

Restless legs syndrome (RLS) A disorder in which the patient experiences crawling, aching, or other disagreeable sensations in the calves that can be relieved by movement. RLS is a frequent cause of difficulty falling asleep at night.

Sedative A medication that has a calming effect and may be used to treat nervousness or restlessness. Sometimes used as a synonym for hypnotic.

Sleep latency The amount of time that it takes to fall asleep. Sleep latency is measured in minutes and is important in diagnosing depression.

Somnambulism Another term for sleepwalking.

conditions depends on successful treatment of the underlying problem. The prognosis for primary sleep disorders is affected by many things, including the patient's age, sex, occupation, personality characteristics, family circumstances, neighborhood environment, and similar factors.

Prevention

There is no known way to prevent sleep disorders, although having a good, regular, sleep schedule with a nighttime ritual intended to reduce stress may help.

Parental concerns

Children who do not get enough sleep, or do not get good quality sleep, may seem irritable or uncooperative during the day. Lack of sleep reduces the ability to concentrate and decreases mental functioning, so children who are not getting enough good sleep at night may have poor concentration skills and poor academic performance.

Resources

BOOKS

Kryger, Meir H., Thomas Roth, William C. Dement, eds. Principles and Practice of Sleep Medicine, 3rd ed. Philadelphia: Saunders, 2000.

Reite, Martin, John Ruddy, and Kim Nagel. Concise Guide to Evaluation and Management of Sleep Disorders, 3rd ed. Washington, DC: American Psychiatric Publishing, 2002.

ORGANIZATIONS

National Sleep Foundation. 1522 K Street, NW, Suite 500, Washington, DC 20005. Web site: <www.sleepfoundation.org>.

Tish Davidson, A.M. Rebecca J. Frey, PhD

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Sleep Disorders

Sleep disorders

Definition

Sleep disorders are a group of syndromes characterized by disturbances in the amount, quality, or timing of sleep, or in behaviors or physiological conditions associated with sleep.

Description

Although sleep is a basic behavior in all animals, its functions in maintaining health are not completely understood. In the past 30 years, however, researchers have learned about the cyclical patterns of different types of sleep and their relationships to breathing, heart rate, brain waves, and other physical functions.

There are five stages of human sleep. Four stages are characterized by non-rapid eye movement (NREM) sleep, with unique brain wave patterns and physical changes. Dreaming occurs in the fifth stage during rapid eye movement (REM) sleep.

  • Stage 1 NREM sleep. This stage occurs while a person is falling asleep and represents about 5% of a normal adult's sleep time.
  • Stage 2 NREM sleep. This stage marks the beginning of "true" sleep. About 50% of sleep time is stage 2 REM sleep.
  • Stages 3 and 4 NREM sleep. Also called delta or slow wave sleep, these are the deepest levels of human sleep and represent 1020% of sleep time. They usually occur during the first 3050% of the sleeping period.
  • REM sleep. REM sleep accounts for 2025% of total sleep time. It usually begins about 90 minutes after the person falls asleep, an important measure called REM latency. REM sleep alternates with NREM sleep about every hour and a half throughout the night. REM periods increase in length over the course of the night.

The average length of nighttime sleep varies among people. Most adults sleep between seven and nine hours a night.

Sleep disorders are classified according to their causes. Primary sleep disorders are distinguished as those that are not caused by other mental disorders, prescription medications, substance abuse, or medical conditions. The two major categories of primary sleep disorders are the dyssomnias and the parasomnias.

Dyssomnias

Dyssomnias are primary sleep disorders in which the patient suffers from changes in the amount, restfulness, and timing of sleep. The most important dyssomnia is primary insomnia, which is defined as difficulty in falling asleep or remaining asleep that lasts for at least one month. It is estimated that 35% of adults in the United States experience insomnia during any given year. Primary insomnia usually begins during young adulthood or middle age.

Hypersomnia is a condition marked by excessive sleepiness during normal waking hours. The patient has either lengthy episodes of daytime sleep or episodes of daytime sleep on a daily basis even though he or she is sleeping normally at night. The number of people with primary hypersomnia is unknown, although 510% of patients in sleep disorder clinics have the disorder. Primary

hypersomnia usually affects young adults between the ages of 15 and 30.

Nocturnal myoclonus and restless legs syndrome (RLS) can cause either insomnia or hypersomnia in adults. Patients with nocturnal myoclonus, sometimes called periodic limb movement disorder (PLMD), awaken because of cramps or twitches in the calves and feel sleepy the next day. RLS patients have a crawly or aching feeling in their calves that can be relieved by moving or rubbing the legs. RLS often prevents the patient from falling asleep until the early hours of the morning.

Narcolepsy is a dyssomnia characterized by recurrent "sleep attacks" (abrupt loss of consciousness) lasting 1020 minutes. The patient feels refreshed by the sleep, but typically feels sleepy again several hours later. Narcolepsy has three major symptoms in addition to sleep attacks: cataplexy (sudden loss of muscle tone and stability), hallucinations, and sleep paralysis. About 40% of patients with narcolepsy have or have had another mental disorder. Although narcolepsy is considered an adult disorder, it has been reported in children as young as three years old. Almost 18% of patients with narcolepsy are 10 years old or younger. It is estimated that 0.020.16% of the general population suffers from narcolepsy.

Breathing-related sleep disorders are syndromes in which the patient's sleep is interrupted by problems with his or her breathing. There are three types of breathingrelated sleep disorders:

  • Obstructive sleep apnea syndrome is the most common form, marked by episodes of blockage in the upper airway during sleep. It is found primarily in obese people. Patients with this disorder typically alternate between periods of snoring or gasping (when their airway is partly open) and periods of silence (when their airway is blocked). Very loud snoring is characteristic of this disorder.
  • Central sleep apnea syndrome is primarily found in elderly patients with heart or neurological conditions that affect their ability to breathe properly.
  • Central alveolar hyperventilation syndrome is found most often in extremely obese people. The patient's airway is not blocked, but his or her blood oxygen level is too low.
  • Mixed-type sleep apnea syndrome combines symptoms of both obstructive and central sleep apnea.

Circadian rhythm sleep disorders are dyssomnias resulting from a discrepancy between the person's daily sleep/wake patterns and the demands of social activities, shift work, or travel. There are three circadian rhythm sleep disorders: delayed sleep phase (going to bed and arising later than most people); jet lag (traveling to a new time zone); and shift work.

Parasomnias

Parasomnias are primary sleep disorders in which the patient's behavior is affected by specific sleep stages or transitions between sleeping and waking.

Nightmare disorder is a parasomnia in which the patient is repeatedly awakened by frightening dreams. Approximately 1050% of children between three and five years old have nightmares. They occur during REM sleep, usually in the second half of the night.

Sleep terror disorder is a parasomnia in which the patient awakens screaming or crying. Unlike nightmares, sleep terrors typically occur in stage 3 or stage 4 NREM sleep during the first third of the night. The patient may be confused or disoriented for several minutes and may not remember the episode the next morning. Sleep terror disorder is most common in children 412 years old. It affects about 3% of children and fewer than 1% of adults.

Sleepwalking disorder (somnambulism) occurs when the patient is capable of complex movements during sleep, including walking. Sleepwalking occurs during stage 3 and stage 4 NREM sleep during the first part of the night. In addition to walking around, patients with sleepwalking disorder have been reported to eat, use the bathroom, unlock doors, or talk to others. It is estimated that 1030% of children have at least one episode of sleepwalking. However, only 15% meet the criteria for sleepwalking disorder. The disorder is most common in children 812 years old.

Sleep disorders related to other conditions

Substances, living situations, and physical or mental disorders that can cause sleep disorders include:

  • Mental disorders, especially depression or one of the anxiety disorders, can cause sleep disturbances. Psychiatric disorders are the most common cause of chronic insomnia.
  • Medical conditions like Parkinson's disease , Huntington's disease, viral encephalitis, brain disease, and thyroid disease may cause sleep disorders.
  • Such substances as drugs, alcohol, and caffeine frequently produce disturbances in sleep patterns.
  • Emotional stress and hormone imbalances can also cause sleep problems.
  • Job-related stress is a common factor in sleep disorders. Police officers, firefighters, and other emergency workers have a higher-than-average rate of sleep disorders.
  • Sleeping arrangements can be a factor. People who must share a bedroom with someone who snores heavily sometimes develop sleep disorders. In addition, Research has shown that co-sleeping (small children sleeping in the same bed as their parents) is stressful for the children and contributes to sleep disorders.
  • Such prescription medications as antihistamines, corticosteroids, asthma medicines, and drugs that affect the central nervous system can affect sleep patterns.

Causes & symptoms

The causes of sleep disorders have already been discussed with respect to the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) classification of these disorders.

The most important symptoms of sleep disorders are insomnia and sleepiness during waking hours. Insomnia is the more common of the two symptoms and encompasses the inability to fall asleep at bedtime, repeated awakening during the night, and/or inability to go back to sleep once awakened.

Sleep disorders can have a number of negative health consequences in addition to general feelings of tiredness. Studies have shown that people with sleep disorders are at increased risk of having serious motor vehicle accidents and fatal workplace accidents.

Diagnosis

Diagnosis of sleep disorders usually requires a psychological history as well as a medical history. With the exception of sleep apnea syndromes, physical examinations are not usually revealing. The doctor may also talk to other family members in order to obtain information about the patient's symptoms. Psychological tests or inventories are used because insomnia is frequently associated with mood or affective disorders.

Patients may be asked to keep a sleep diary for one to two weeks to evaluate the sleep disturbance. Medications taken, the length of time spent in bed, and the quality of sleep are recorded.

If breathing-related sleep disorders, myoclonus, or narcolepsy are suspected, the patient may be tested in a sleep laboratory or at home with portable instruments. Polysomnography records physiological functions that can be used to help diagnose sleep disorders as well as conduct research into sleep.

Treatment

General recommendations

General recommendations for getting more restful sleep include:

  • Waiting until one feels sleepy before going to bed.
  • Not using the bedroom for work, reading, or watching television.
  • Arising at the same time every morning.
  • Avoiding smoking and drinking caffeinated liquids.
  • Limiting fluids after dinner and avoiding alcohol.
  • Avoiding high-sugar or high-calorie snacks at bedtime.
  • Avoiding highly stimulating activities before bed, such as watching a frightening movie, playing competitive computer games, etc.
  • Avoiding tossing and turning in bed. Instead, the patient should get up and listen to relaxing music or read.

Herbal remedies

Herbal remedies that are helpful in relieving insomnia include:

  • catnip (Nepeta cataria ): poor sleep
  • chamomile (Matricaria recutita ): anxiety
  • chrysanthemum (Chrysanthemum morifolium ): insomnia
  • hops (Humulus lupulus ): overactive mind
  • lime blossom (Tilia cordata ): anxiety
  • linden (Tilia species): anxiety
  • oats (Avena sativa ): poor sleep and nervous exhaustion
  • passionflower (Passiflora incarnata ): anxiety and muscle cramps
  • skullcap (Scutellaria lateriflora ): nervous tension
  • squawvine (Mitchella repens ): insomnia
  • St. John's wort (Hypericum perforatum ): depression
  • valerian (Valeriana officinalis ): anxiety
  • vervain (Verbena officinalis ): nervous tension, sleep apnea

According to Prevention magazine, insomnia is the sixth most common condition treated with herbal formulas in the United States; it accounts for 18% of all use of herbal preparations. Some herbs used for insomnia are safer than others. Persons who are using alternative remedies, whether to treat insomnia or other conditions, should always tell their doctor what they are taking, how much, and how often. This warning is important because some herbal preparations that are safe in themselves can interact with prescription medications.

Dietary supplements and modifications

Some naturopaths recommend Vitamins B6, B12, and D for the relief of insomnia. Calcium and magnesium are natural sedatives, which helps to explain the traditional folk recommendation of drinking a glass of warm milk at bedtime. Tryptophan may relieve insomnia; as turkey is high in tryptophan, a turkey sandwich as a bedtime snack may be helpful. Melatonin is widely used to induce sleep although adequate studies of its effectiveness are lacking.

Other treatments

A wide variety of other alternative treatments that may be helpful in treating sleep disorders include:

  • Acupressure. The pressure points on both heels, the base of the skull, between the eyebrows, and on the inside of the wrists can be used to relieve insomnia.
  • Acupuncture. The specific treatment for insomnia depends upon the cause.
  • Aromatherapy. The use of essential oils of bergamot, lavender , basil, chamomile, neroli, marjoram, or rose promotes relaxation .
  • Ayurvedic medicine. Ayurvedic remedies for insomnia include scalp and soles massage with sesame, brahmi, or jatamamsi oils, a warm bath, or a nutmeg ghee paste applied to the forehead and around the eyes. Nightmares are treated with scalp and soles massage with brahmi or bhringaraj oils, tranquility tea (jatamamsi, brahmi, ginkgo, and licorice root), and yoga . Sleep apnea is treated by changing sleep positions, humidifying the air, and nasya (nose drops) with warm brahmi ghee.
  • Biofeedback. This technique can promote relaxation.
  • Chinese medicine. Practitioners of traditional Chinese medicine usually treat insomnia as a symptom of excess yang energy. Either magnetite or "dragon bones" are recommended for insomnia associated with hysteria or fear.
  • Chiropractic. Spinal manipulation can reduce stress upon the nervous system, thus allowing relaxation.
  • Colored light therapy . Treatment with true green light can balance the nervous system and may relieve insomnia.
  • Homeopathy. Homeopathic remedies are chosen according to the specific causes of insomnia. They may include: Nux vomica (alcohol or substance-related sleeplessness), Ignatia (emotional upset), Arsenicum (anxiety), Passiflora (mental stress, aches, and pains), and Lycopodium (talking and laughing during sleep).
  • Light/dark therapy involves making the bedroom very dark at night and exposing the patient to early morning sunlight (or a light box).
  • Low-energy emission therapy (LEET) is a clinically proven treatment for chronic insomnia. LEET treatment involves delivering electromagnetic fields through a mouthpiece.
  • Massage. Therapeutic massage can relieve the muscular tension associated with chronic insomnia.
  • Meditation . Regular meditation practice can counteract emotional stress.
  • Reflexology . The use of the reflexology points for the diaphragm, pancreas, ovary/testicle, pituitary, parathyroid, thyroid, and adrenal gland helps to relieve insomnia.
  • Visualization may help to promote relaxation.
  • Yoga can promote relaxation by releasing muscular tension.

Allopathic treatment

Treatment for a sleep disorder depends on its cause. In some cases, rearrangement of the bedroom or changes in sleeping arrangements may be all that is needed. Sedative or hypnotic medications are generally recommended only for insomnia related to a temporary stress because of the potential for addiction or overdose. Trazodone, a sedating antidepressant, is often used for chronic insomnia that does not respond to other treatments. Hypnotic agents include lorazepam, temazepam, and zolpidem.

Bright-light therapy, which was originally introduced as a treatment for seasonal affective disorder , is being tried as a treatment for insomnia in elderly adults. Although the results are not conclusive as of 2002, this form of treatment does appear to benefit many patients. In addition, it does not involve medications, which are more likely to produce side effects in the elderly than in younger patients.

Narcolepsy is treated with such stimulants as dextroamphetamine sulfate or methylphenidate. Nocturnal myoclonus has been successfully treated with clonazepam.

Children with sleep terror disorder or sleepwalking are usually treated with benzodiazepines. Children with nightmare disorder may benefit from limits on violent or frightening television programs or movies.

Psychotherapy is recommended for patients with sleep disorders associated with other mental disorders.

Patients with sleep apnea or hypopnea are encouraged to stop smoking, avoid alcohol or drugs of abuse, and lose weight to improve the stability of the upper airway. In children and adolescents, removal of the tonsils and adenoids is a fairly common and successful treatment for sleep apnea. Most sleep apnea patients are treated with continuous positive airway pressure (CPAP). Sometimes an oral prosthesis is used for mild sleep apnea.

Expected results

The prognosis depends on the specific disorder. Natural remedies often require several weeks to have noticeable effects. Children usually outgrow sleep disorders. Narcolepsy, however, is a lifelong disorder.

Resources

BOOKS

Becker, Philip M. "Sleep Disorders." In Current Diagnosis 9, edited by Rex B. Conn, et al. Philadelphia: W. B. Saunders, 1997.

DeGeronimo, Theresa Foy. Insomnia: 50 Essential Things To Do. New York: Penguin Group, 1997.

Eisendrath, Stuart J. "Psychiatric Disorders: Sleep Disorders." In Current Medical Diagnosis & Treatment 1998, edited by Lawrence M. Tierney, Jr., et al. Stamford, CT: Appleton & Lange, 1997.

Goldson, Edward. "Behavioral Disorders and Developmental Variations: Sleep Disorders." In Current Pediatric Diagnosis & Treatment, edited by William W. Hay, Jr., et al. Stamford, CT: Appleton & Lange, 1997.

Pelletier, Kenneth R., MD. The Best Alternative Medicine, Part II, "CAM Therapies for Specific Conditions: Insomnia." New York: Simon & Schuster, 2002.

Reichenberg-Ullman, Judyth, and Robert Ullman. Homeopathic Self-Care: The Quick and Easy Guide for the Whole Family. Rocklin, CA: Prima Publishing, 1997.

Sanders, Mark H. "Sleep Apnea and Hypopnea." In Conn's Current Therapy. Edited by Robert E. Rakel. Philadelphia: W.B. Saunders, 1998.

"Sleep Disorders." In Diagnostic and Statistical Manual of Mental Disorders. 4th ed., text revision. Washington, DC: American Psychiatric Association, 2000.

Vasant, Lad. The Complete Book of Ayurvedic Home Remedies. New York: Harmony Books, 1998.

Wiedman, John. Desperately Seeking Snoozin': The Insomnia Cure from Awake to Zzzz. Memphis, TN: Towering Pines Press, 1997.

PERIODICALS

Akerstedt, T., P. Fredlund, M. Gillberg, and B. Jansson. "A Prospective Study of Fatal Occupational AccidentsRelationship to Sleeping Difficulties and Occupational Factors." Journal of Sleep Research 11 (March 2002): 69-71.

Hunsley, M., and E. B. Thoman. "The Sleep of Co-Sleeping Infants When They Are Not Co-Sleeping: Evidence That Co-Sleeping Is Stressful." Developmental Psychobiology 40 (January 2002): 14-22.

Lushington, K., and L. Lack. "Non-Pharmacological Treatments of Insomnia." Israeli Journal of Psychiatry and Related Sciences 39 (2002): 36-49.

Montgomery, P., and J. Dennis. "Bright Light Therapy for Sleep Problems in Adults Aged 60+ (Cochrane Review)." Cochrane Database Systems Review 2002: CD003403.

Neylan, T. C., T. J. Metzler, S. R. Best, et al. "Critical Incident Exposure and Sleep Quality in Police Officers." Psychosomatic Medicine 64 (March-April 2002): 345-352.

Powell, N. B., K. B. Schechtman, R. W. Riley, et al. "Sleepy Driving: Accidents and Injury." Otolaryngology, Head and Neck Surgery 126 (March 2002): 217-227.

ORGANIZATIONS

American Sleep Disorders Association. 1610 14th Street NW, Suite 300. Rochester, MN 55901. (507) 287-6006.

National Sleep Foundation. 1367 Connecticut Avenue NW, Suite 200. Washington, DC 20036. (202) 785-2300.

Belinda Rowland

Rebecca J. Frey, PhD

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Sleep and Sleep Disorders

Sleep and sleep disorders

Sleep is a normal state of decreased consciousness and lowered metabolism during which the body rests. As a natural, necessary, and daily experience for humans and most other vertebrates (animals that have a backbone or spinal column), sleep has four stages through which we cycle several times a night. A sleep disorder is any condition that interferes with our regular sleep cycle, ranging from insomnia (pronounced in-SAHM-nee-a) to narcolepsy (pronounced NAHR-ko-lehp-see).

Necessity of sleep

Although sleep is something everyone experiences everydaythe average person sleeps approximately one-third of his or her lifetimescience still has a great deal to learn about this very common phenomenon. We all recognize that sleep is a necessity and that although we can go without it for a while, it eventually becomes as important to our health and well-being as food, air, and water. We also know that when we sleep well, we seem to wake refreshed and alert, and generally feel ready to face the day. When we do not sleep well, however, we know that the chances are greater that we will feel less sharp and probably more grumpy than usual, and that everything may be a little more difficult to do. People who regularly experience a problem falling asleep or staying asleep may be suffering from some form of sleep disorder. Serious sleep disorders can wreck our personal lives, make us unproductive at work, and overall, injure the quality of our lives.

Purpose of sleep

The real nature and purpose of sleep has long puzzled scientists. Ancient humans believed that the soul left the body during sleep, and the well-known prayer that includes the words, "if I should die before I wake," tells us something about the fear we may experience when we surrender to unconsciousness every night. From a scientific standpoint, sleep was not able to be studied seriously until the twentieth century when certain instruments were invented that could actually measure brain activity. In 1929, the German psychiatrist Hans Berger (18731941) developed a machine called an electroencephalograph (pronounced ee-lek-troen-SEH-fuh-low-graf), which could pick up and record the signals produced by the brain's electrical activity. By the mid-1930s, Berger was producing a graphic picture or photograph of people's brain waves, both waking and asleep, that was called an EEG or electroencephalogram (pronounced ee-lek-tro-en-SEH-fuh-low-gram). An EEG is made by placing electrode wires on a person's scalp that receive the electrical activity produced by the brain's neurons or nerve cells. Neurons in the brain receive and transmit information and are able to communicate with the rest of the body. When they are "firing" or activated, charged electrical particles are produced. It is these charges that the EEG can sense and record.

Words to Know

Apnea: Cessation of breathing.

Circadian rhythm: The behavior of animals when influenced by the 24-hour day/night cycle.

Delta sleep: Slow-wave, stage 4 sleep that normally occurs before the onset of REM sleep.

Insomnia: Inability to go to sleep or stay asleep.

Narcolepsy: Condition characterized by brief attacks of deep sleep.

REM sleep: The period of sleep during which eyes move rapidly behind closed eyelids and when dreams most commonly occur.

Stages of human sleep

Scientists who study the brain have discovered that certain types and levels of brain activity have their own typical patterns or register their own type of waves on an EEG. They also have come to recognize and name the certain types of waves that relate to certain types of activity. For example, when a person first closes his or her eyes after lying down, "theta" waves, or waves that have a certain number of cycles per second, are produced. As a person falls into deeper stages of sleep, the waves become slower. Although they do not know exactly why this happens, scientists do know that most vertebrates pass through two distinct types of sleep, and that humans have four separate levels of sleep. In Stage I we have just fallen asleep, usually after about fifteen minutes, and we have entered a light, dozing sleep. Here we show irregular and fairly fast theta waves. Stage II is the first true stage of sleep, and our EEG registers "spindle waves" in bursts. Stage III marks the beginning of deep sleep, and theta waves that are slowed-down appear. Stage IV is our deepest sleep and has the slowest waves of all, sometimes called delta waves. This progression from stages one to four takes about one hour, and then the cycle reverses itself, going backwards to Stage I. This entire cycle repeats itself three or four times during the night.

REM sleep

At the end of the first cycle, each time a person reenters Stage I, he or she begins an interesting sleep stage called Rapid Eye Movement or REM sleep. It is during this stage that our dreaming occurs, and even though this is a stage of light sleep, most people are difficult to awaken when in REM sleep. Our bodies are also very active during REM, and besides our eyes moving side to side, we usually toss and turn quite a bit. of sleep a night. Most adults average around seven and a half hours of sleep a night, although studies have shown that some people need as little as five or six hours. Regardless, everyone needs their REM sleep. We spend about three-fourths of a night in non-REM sleep and one-fourth dreaming in REM sleep. Amazingly, the brain waves registered during REM are almost the same as those when we are awake.

How much sleep?

Our sleep patterns change as we age, and infants sleep far longer and deeper than adults. Newborns may sleep as much as seventeen hours a day, while five-year-olds about twelve hours a night. Teenagers need about nine and a half hours a night, although they seldom get that much. For some reason, many people experience the best and most satisfying sleep of their lives during the middle teen years. Some very old adults need only five or six hours a night.

Insomnia

Although sleep is something that is common to us all, many peopleas many as 30 million Americanssuffer from some sort of sleep disorder or problem. Insomnia or difficulty falling or staying asleep is the most common disorder. While everyone will experience this at some time, if you regularly have trouble getting to sleep or staying asleep and feel next-day sleepiness and difficulty concentrating, you probably have insomnia. Some of the causes of insomnia are psychological factors like stress. Your lifestyle itself may cause a different kind of stress if you regularly work or party very late or drink alcohol or beverages with caffeine. An unsettling environment can be a factor, as can physical problems that cause pain. Certain medications can also cause sleeping problems. A simple description of insomnia is that it happens when the part of the brain used for thinking does not turn off.

Narcolepsy

Probably the most serious sleeping disorder is a chronic brain disorder called narcolepsy (pronounced nar-ka-LEP-see). It affects some 200,000 Americans and is recognized primarily by a sudden, almost uncontrollable need to sleep that can occur at any time. Narcoleptics may also experience sudden muscle weakness, a feeling of being paralyzed, and even especially frightening nightmares and hallucinations. It can be brought on by being bored but also by being surprised, angry, or suddenly upset. The poor narcoleptic always feels tired during the day. This difficult condition is a genetic disorder, meaning that it runs in families. It is managed with stimulant-type drugs.

Sleep apnea

Sleep apnea (pronounced AP-knee-ah) sounds like a funny condition when it is described, except it can be potentially very serious. Sufferers from sleep apnea can develop high blood pressure and even risk heart damage. This condition occurs most often in middle-aged men who literally stop breathing while asleep. When this happens, they usually snort or snore and gasp for breath, waking themselves up. This can happen as often as two hundred times a night, obviously wrecking any chance of a good night's sleep and leading to daytime sleepiness, headaches, irritability, and even learning and memory problems. Most cases are caused by some sort of abnormality in the nose, throat, or other part of the airway. Some sufferers can wear a masklike device over their nose whose regulated pressure prevents their throat from collapsing during sleep. Others may need surgery.

Other sleep disorders

There are several other types of sleep disorders, some serious and some simply bothersome. Some people have Restless Leg Syndrome (RLS), in which they experience terribly uncomfortable sensations in their legs and have to move, stretch, or rub their legs all the time. This naturally disturbs their sleep. This condition is sometimes treated with drugs. Others have Periodic Limb Movement (PLM), in which their legs (and sometimes their arms) periodically twitch and jerk, sometimes for as long as several hours. Like RLS, the cause is unknown.

Many people who work or are active during the night and try to sleep during the day experience difficulty sleeping. This is called a disruption of one's circadian (pronounced sir-KAY-dee-an) rhythm. This means that the body's internal clock is out of sync with the twenty-four-hour day. The "jet lag" we feel after changing time zones is a temporary example of such a disorder. Finally, many people at some time have experienced other minor disorders, such as sleepwalking, "night terrors," teeth grinding, and talking in one's sleep.

Although scientists are still not sure exactly what the function of sleep iswhether the brain is "housekeeping" and reorganizing the information it took in during the day or simply conserving its energythey do know that it provides all-important rest to the mind and body, and that rest is essential to good health. Therefore, sleep is not simply a "time out" from business. It is a necessary time of restoration. This is demonstrated by the ill effects experienced by those who suffer from a sleep disorder.

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Sleep Disorders

Sleep disorders

Chronic disturbances in the quantity or quality of sleep that interfere with a person's ability to function normally.

An estimated 15 percent of Americans have chronic sleep problems, while about 10 percent have occasional trouble sleeping. Sleep disorders are listed among the clinical syndromes in Axis I of the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders. They may be either primary (unrelated to any other disorder, medical or psychological) or secondary (the result of physical illness, psychological disorders such as depression , drug or alcohol use, stress , or lifestyle factors, such as jet lag).

The Association for Sleep Disorders Centers has divided sleep problems into four categories. The first and most common is insomnia (Disorders of Initiating and Maintaining Sleep). In insomnia, sleep loss is so severe that it interferes with daytime functioning and well-being. Three types of insomnia have been identified (although a single person can have more than one): sleep-onset insomnia (difficulty falling asleep); sleep-maintenance

insomnia (difficulty staying asleep); and terminal insomnia (waking early and not being able to go back to sleep). While insomnia can occur at any stage of life, it becomes increasingly common as people get older.

Some cases of insomnia are thought to be caused by abnormalities in the part of the brain that controls sleeping and waking. However, insomnia commonly has a wide variety of non-neurological causes, including stress, physical pain , irregular hours, and psychological disorders. Temporary acute insomnia related to a major event or crisis can turn chronic if a person becomes overly anxious about sleep itself and is unable to return to his or her normal sleep pattern. Called learned or behavioral insomnia, this problem troubles about 15 percent of people who seek professional help. In about 30 percent of cases, an underlying psychological disorderoften depressionis responsible for insomnia. Disorders that can cause insomnia include anxiety disorders (such as post-traumatic stress disorder), obsessive-compulsive disorder , and schizophrenia . Normal sleep may be disrupted by a variety of substances, including caffeine, nicotine, alcohol, appetite suppressants, and prescription medications such as steroids, thyroid medications, and certain antihypertensive drugs.

Many people take medications for insomnia, ranging from over-the-counter preparations (which are basically antihistamines) to prescription drugs including barbiturates and benzodiazepines. The American Sleep Disorders Association recommends benzodiazepines (a class of drugs that includes Valium and Restoril) over barbiturates and other sedatives, although only for limited use to treat temporary insomnia or as a supplement to psychotherapy and other treatments for chronic insomnia. Benzodiazepines can lead to tolerance and addiction, and withdrawal can actually worsen insomnia. People who take sleeping pills for two weeks or more and then quit are likely to experience a rebound effect that can disrupt their sleep for a period of up to several weeks.

A variety of behavioral treatments are available for insomnia which, when practiced consistently, can be as effective as medication without side effects or withdrawal symptoms. Different types of relaxation therapy, including progressive muscle relaxation, hypnosis , meditation, and biofeedback , can be taught through special classes, audiotapes, or individual sessions. Cognitive therapy focuses on deflecting anxiety-producing thoughts and behaviors at bedtime. Stimulus control therapy is based on the idea that people with learned insomnia have become conditioned to associate their beds with wakefulness. Persons involved in this type of therapy are not allowed to remain in bed at night if they can not fall asleep; they are instructed to go to another room and engage in a non-stressful activity until they become sleepy. In the morning, they must arise at a set hour no matter how much or little sleep they have had the night before. Finally, sleep restriction therapy consists of limiting one's hours in bed to the average number of hours one has generally been sleeping and then gradually increasing them.

The second category of sleep disorder is hypersomnia, or Disorders of Excessive Somnolence. People affected by any type of hypersomnia report abnormal degrees of sleepiness, either at night or in the daytime. While the most common causes are sleep apnea and narcolepsy , hypersomnia may also be caused by physical illness, medications, withdrawal from stimulants, or other psychological disorders. Sleep apnea consists of disrupted breathing which wakens a person repeatedly during the night. Though unaware of the problem while it is occurring, people with sleep apnea are unable to get a good night's sleep and feel tired and sleepy during the day. The condition is generally caused either by a physical obstruction of the upper airway or an impairment of the brain's respiration control centers. Common treatment methods include weight loss (obesity is a risk factor for the condition), refraining from sleeping on one's back, and medications that reduce rapid eye movement (REM) sleep. A technique called continuous positive airway pressure (CPAP) pushes air into the sleeper's throat all night through a small mask, preventing the airway from collapsing. In addition, a surgical procedure is available that modifies the upper airway to allow for freer breathing.

The other main type of hypersomnia is narcolepsy sudden attacks of REM sleep during waking hours. Many narcoleptics experience additional symptoms including cataplexy (a sudden loss of muscle tone while in a conscious state), hallucinations and other unusual perceptual phenomena, and sleep paralysis, an inability to move for several minutes upon awakening. Between 200,000 and 500,000 Americans are affected by narcolepsy, which is caused by a physiological brain dysfunction that can be inherited or develop after trauma to the brain from disease or injury. Treatments include stimulants to combat daytime sleepiness, tricyclic anti-depressants to suppress REM sleep, and other medications to control cataplexy.

Disorders of the Sleep-Wake Schedulethe third type of sleep disturbanceare also called circadian rhythm disorders because they interfere with the 24-hour biological clock that regulates many bodily processes. People with these disorders have trouble adhering to the sleep-wake schedule required by their job or environment , often due to shift work or jet lag. However, some persons suffer from delayed or advanced sleep onset problems with no external aggravating factor. Exposure to bright lights and chronotherapy, a technique for resetting one's biological clock, have been effective in the treatment of some circadian rhythm disorders.

Parasomnias, the final category of sleep disorder, involve unusual phenomenanightmares, sleep terrors, and sleepwalkingthat occur during sleep or during the period between sleeping and waking. Nightmare and sleep terror disorders are similar in that both occur mainly in children and involve frightening nighttime awakenings (in the case of sleep terrors, the person is awakened from non-REM sleep by feelings of agitation that can last for up to 10 minutes). Both are often outgrown but may be treated with psychotherapy, low-dose benzodiazepines, and, in the case of nightmare disorder, relaxation training. Sleepwalking occurs during the deep non-REM sleep of stages three and four and is also most common in children, who tend to outgrow it after the age of 12. It is also more common among males than females. The greatest danger posed by sleepwalking is injury through falls or other mishaps.

Other features of parasomnias include bruxism (teeth grinding) and enuresis (bedwetting). Both are often stress-related, although enuresis may also be caused by genitourinary disorders, neurological disturbances, or toilet training problems. Bruxism may be relieved through relaxation techniques or the use of a custom-made oral device that discourages grinding or at least prevents tooth damage. Enuresis often responds to the medication imipramine (Tofranil) and various behavior modification techniques. A parasomnia only identified within the past decade is REM sleep behavior disorder. Those affected by this conditionusually middle-aged or older menengage in vigorous and bizarre physical activities during REM sleep in response to dreams , which are generally of a violent, intense nature. As their actions may injure themselves or their sleeping partners, this disorder, thought to be neurological in nature, has been treated with hypnosis and medications including clonazepam and carbamazepine.

Further Reading

Hales, Dianne R. The Complete Book of Sleep: How Your Nights Affect Your Days. Reading, MA: Addison-Wesley Longman, 1981.

Lamberg, Lynne. The American Medical Association Guide to Better Sleep. New York: Random House, 1984.

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sleep disorders

sleep disorders The ability to fall asleep, stay asleep, and wake up are all considered inalienable rights. We should neither stuporously wander about our houses nor suddenly decide to jump off our beds into imaginary swimming pools. The child's prayer, ‘Now I lay me down to sleep’, epitomizes the fond hope that sleep is a safe passage across a sea of unconsciousness undisturbed by life-threatening deficits in vital physiological processes. Still, it should have come as no surprise that a system as complicated and differentiated as the brain mechanisms underlying sleep and dreaming would have its own intrinsic propensity for dysfunction and disorder as well as its amazing capacity as a health-conveying operation. And the normal variation in sleep propensity, sleep depth, sleep length, and sleep stage distribution is already proof that such mundane events as excessive daytime sleepiness, or its converse, excessive night-time wakefulness (insomnia) should be viewed at least in part as expressions of extremes of normal physiology.

Yet even the most sophisticated and perspicacious sleep scientists were unprepared for the discovery that breathing sometimes stopped or was blocked in sleep (as it is in sleep apnea) or the recognition that all of the symptoms of the compelling need to sleep (as seen in narcolepsy) could be explained as abnormalities of sleep neurophysiology. More surprising still were the twin discoveries that sleepwalking, sleep-talking, and bedwetting had little to do with dreaming but that a previously unrecognized process, the REM sleep behaviour disorder, was not only dream enactment but the harbinger of degenerative disease of brain motor control systems!

There are three major kinds of sleep problems and each can be understood through sleep physiology:1. Difficulty falling asleep (which is caused by excessively strong or inadequately suppressed brain drives toward waking) — the classic example is insomnia.2. Difficulty staying awake (caused by excessively strong or inadequately suppressed brain drives toward sleep). The classic example is narcolepsy.3. Abnormal movements that occur as the depth of sleep varies over the course of the night. For example, the movement-generating centres of the brain can sometimes become active without the brain's consciousness-generating arousal systems becoming simultaneously activated to waking levels. The classic example is sleepwalking.The sleep apnea syndromes are an ambiguous but critically important class of sleep disorder with characteristics of all three categories. Victims of this life-threatening tendency to stop breathing when they fall asleep — and then to choke when they make compensatory efforts to wake up and breathe again — may be insomniac (because their bodies will literally not allow them to go to sleep); they may have excessive sleepiness by day (because they are chronically sleep deprived); and their laboured efforts to breathe while asleep can be seen as a form of chronic abnormal sleep movement, which, in the long term, may prove to be much more physiologically harmful than other sorts of abnormal sleep movements such as sleepwalking.

Sleep apnea sufferers are usually overweight (which makes breathing more difficult as the airway closes normally — causing snoring — at sleep onset) and male (which deprives them of the unexplained protection of sleep breathing afforded by female sex hormones). But they also just exaggerate the surprising normal tendency of men to have long pauses in their breathing efforts, especially during NREM sleep but also in REM. As their oxygen hunger increases and their brain alarm clock arouses them, they make a gasping effort to gulp air, at which point their flaccid, fat-compressed airway closes and they move even closer to self-strangulation. Because treatment is now quite effective it is crucial that any person suspected of having sleep apnea consult a physician or a sleep disorders centre.

Narcolepsy is a rare but instructive illness with four defining attributes: (i) excessive daytime sleepiness and irresistible attacks of sleep; (ii) the sudden loss of postural muscle tone (called cataplexy, often leading to total collapse; (iii) the occurrence of frightening dream hallucinations at sleep onset and upon awakening; and (iv) the persistence of REM sleep motor paralysis, also on arousal from sleep.

All of these symptoms are manifestations of a genetically-determined failure to inhibit REM sleep physiology, which most of us can do quite easily, especially during waking. Like new-borns, many adult narcoleptic patients have prolonged REM sleep bouts at sleep onset. Effective treatment is achieved using drugs that potentiate the brain chemicals responsible for effective waking, and/or suppression of the brain chemicals responsible for REM sleep.

Insomnia is by far the most prevalent disorder of sleep. It is also the most problematic to manage, because none of the myriad sedative drugs available for its relief is a physiological sleep inducer or enhancer. For this reason all of the effective sedatives have one or more defects: undesirable side-effects, diminished efficacy with prolonged use, or a worsening of symptoms upon withdrawal.

Because so much insomnia is psychologically and behaviourally driven, effective treatment should always include attention to such factors as (i) regular, early times of retirement; (ii) elimination of the commonly abused anti-sleep ingestants tobacco and alcohol; (iii) a review of daytime work and interpersonal concerns with special attention to identifying and eliminating the sources of nocturnal rumination and anxiety; (iv) the prescription of sleep-enhancing aerobic exercise; and (v) instruction in systematic body relaxation techniques.

This naturalistic approach to insomnia does not deny its sometimes strong physiological basis, which may demand pharmacological adjuncts, but it is cautious and conservative in warning against the undue expectation and the unacceptable risks of uncritical sedative treatment.

The REM sleep behaviour disorder is easily distinguished from ordinary sleepwalking. Sleepwalking is a self-limited and usually harmless problem of adolescence and early adulthood that occurs in NREM sleep and disappears when that sleep stage declines in the fourth decade. By contrast, the REM sleep behaviour disorder usually begins at that age or later, and reflects the dangerous and prognostically grave failure to inhibit the motor commands of REM sleep that are normally experienced as only the illusion of movement during dreaming.

Early degeneration of the brain (and especially Parkinson's disease) is heralded by REM sleep behaviour disorder, but it has also recently been reported to arise in younger subjects who have been treated for depression with drugs that specifically potentiate serotonin, one of the chemicals that the brain uses to energize itself in waking and to influence the excitability of the motor system in all of its states.

The study of sleep disorders is still a young, rapidly-developing field at the interface of neurology, psychiatry, and internal medicine. Its inventory of disorders, its methods of investigation, and its approaches to treatment can all be expected to change rapidly in the next few decades.

J. Allan Hobson


See also body clock; sleep; snoring.

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Sleep disorders

Sleep disorders

Definition

Sleep disorders are chronic disturbances in the quantity or quality of sleep that interfere with a person's ability to function normally.

Description

An estimated 15% of Americans have chronic sleep problems, while about 10% have occasional trouble sleeping. Sleep disorders are listed among the clinical syndromes in Axis I of the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders , also known as the DSM. They may be either primary (unrelated to any other disordermedical or psychological) or secondary (the result of physical illness, psychological disorders, or drug or alcohol use).

In the revised fourth edition of the DSM (DSM-IV-TR ), the primary sleep disorders are categorized as either dyssomnias or parasomnias. Dyssomnias pertain to the amount, quality, or timing of sleep, whereas parasomnias pertain to abnormal behavioral or physiological events that occur while sleeping. Dyssomnias include:

  • Primary insomniadifficulty getting to sleep or staying asleep. Sleep loss is so severe that it interferes with daytime functioning and well-being. Three types of insomnia have been identified (although a single person can have more than one): sleep-onset insomnia (difficulty falling asleep); sleep-maintenance insomnia (difficulty staying asleep); and terminal insomnia (waking early and not being able to go back to sleep). While insomnia can occur at any stage of life, it becomes increasingly common as people get older.
  • Primary hypersomnia excessive sleepiness either at night or during the day.
  • Narcolepsy sudden attacks of REM sleep during waking hours. Many narcoleptics experience additional symptoms including cataplexy (a sudden loss of muscle tone while in a conscious state), hallucinations and other unusual perceptual phenomena, and sleep paralysis, an inability to move for several minutes upon awakening. The disorder is caused by a physiological brain dysfunction that can be inherited or develop after trauma to the brain from disease or injury.
  • Breathing-related sleep disorder abnormalities in breathing cause sleep disruptions. Sleep apnea consists of disrupted breathing which wakens a person repeatedly during the night. Though unaware of the problem while it is occurring, people with sleep apnea are unable to get a good night's sleep and feel tired and sleepy during the day. The condition is generally caused either by a physical obstruction of the upper airway or an impairment of the brain's respiration control centers.
  • Circadian rhythm sleep disorder environmental disruptions to an individual's internal 24-hour-clock affect his or her sleep patterns. This disorder has four subtypes: delayed sleep phase type, jet lag type, shift work type, and unspecified type.

Parasomnias include:

  • Nightmare disorder nightmares repeatedly awaken the affected individual.
  • Sleep terror disorder affected individual is repeatedly awakened from sleep and remains awake and frightened for a short period of time (about 10 minutes or so, usually less), and during that time, the individual is difficult to awaken or comfort. No dream is recalled, and the person often does not remember the event the following day.
  • Sleepwalking disorder repeated episodes of motor activity during sleep, including getting out of bed and walking around.

Other features of parasomnias not listed in the DSM-IV-TR include bruxism (teeth grinding) and enuresis (bed-wetting). Both are often stress-related, although enuresis may also be caused by genitourinary disorders, neurological disturbances, or toilet training problems. A parasomnia only identified in the late twenieth century is REM sleep behavior disorder. Those affected by this conditionusually middle-aged or older menengage in vigorous and bizarre physical activities during REM sleep in response to dreams, which are generally of a violent, intense nature. As their actions may injure themselves or their sleeping partners, this disorder, thought to be neurological in nature, has been treated with hypnosis and medications, including clonazepam and carbamazepine .

Resources

BOOKS

American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders. Fourth edition, text revised. Washington DC: American Psychiatric Association, 2000.

Buchman, Dian Duncin. The Complete Guide to Natural Sleep. Collingdale: DIANE Publishing Company, 1999.

Mottolova, Jamin K. Sleep-deficiency, Deprivations, Disturbances and Disorders: Index of New Information and Guide-Book for Consumers, Reference and Research. Washington DC: Annandale, 2002.

Reite, Martin, John Ruddy, and Kim Nagel. Concise Guide to Evaluation and Management of Sleep Disorders. Washington DC: American Psychiatric Publishing Group, Inc., 2002.

ORGANIZATIONS

The American Academy of Sleep Medicine (formerly the American Sleep Disorders Association), and the Sleep Medicine Education and Research Foundation. 6301 Bandel Road, Suite 101, Rochester, MN 55901. Telephone: (507) 287-6006. Web site: <http://www.aasmnet.org>.

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Sleep Disorders

SLEEP DISORDERS

DEFINITION


Sleep disorders are a group of conditions characterized by disturbance in the amount, quality, or timing of a person's sleep. They also include emotional and other problems that may be related to sleep. There are about seventy different sleep disorders. Short-term, temporary changes in a person's sleep pattern are not included in sleep disorders.

DESCRIPTION


Sleep disorders are divided into two major categories. One category consists of disorders in which a person has trouble falling asleep or staying asleep. This category also includes disorders in which a person may fall asleep at inappropriate times. Conditions of these kinds are called dyssomnias. A second category of sleep disorders includes those in which people experience physical events while they are sleeping. Nightmares and sleepwalking are examples of these disorders. Conditions of this type are called parasomnias.

The following are some examples of each type of sleep disorder:

Dyssomnias

  • Insomnia. Insomnia (see insomnia entry) is perhaps the most common of all sleep disorders. About 35 percent of all adults in the United States experience insomnia during any given year. People with insomnia have trouble falling asleep. Often people with this disorder worry or become anxious about not being able to sleep, which can make the problem even worse. Insomnia may begin at any time in a person's life. It tends to be most common in young adulthood and middle age.
  • Hypersomnia. Hypersomnia is a condition in which a person is excessively sleepy during normal waking hours. The person may often fall asleep for lengthy periods during the day, even if he or she has had a good night's sleep. In some cases, patients have difficulty waking up in the morning. They may seem confused or angry when they awaken. About 5 to 10 percent of people who seek help for sleep disorders have hypersomnia. The condition is most common in young adults between the ages of fifteen to thirty.
  • Narcolepsy. Narcolepsy is characterized by sleep attacks over which patients have no control. They may fall asleep suddenly with no warning. The sleep attack may last a few minutes or a few hours. The number of attacks patients experience can vary. People with narcolepsy usually feel refreshed after awakening from a sleep attack but they may become sleepy again a few hours later and experience another attack.

Three other conditions are often associated with narcolepsy: cataplexy, hallucinations, and sleep paralysis. Cataplexy is the sudden collapse of a person's muscles. The person may become completely limp and fall to the ground. A person may also experience hallucinations. Hallucinations are sounds and sights that a person experiences that do not exist in the real world. Sleep paralysis occurs when a person is just falling asleep or just waking up. The person may want to move, but is unable to do so for a few moments.

  • Sleep apnea. Sleep apnea (pronounced AP-nee-uh) is a condition in which a person actually stops breathing for ten seconds or more. The most common symptom of sleep apnea is very loud snoring. Patients with this condition alternate between periods of snoring or gasping and periods of silence.
  • Circadian rhythm sleep disorders. The term circadian (pronounced sir-CAYD-ee-uhn) rhythm refers to the usual cycle of activities, such as waking and sleeping that is common to any form of life. Most people are accustomed to falling asleep after it gets dark out and waking up when it gets light. In certain conditions, this pattern can be disrupted. A person may fall asleep as the sun comes up and wake up as the sun goes down. An example of a circadian sleep disorder is jet lag. People who fly suddenly across many time zones may have their sleep patterns disrupted. It may take a few days before those patterns return to normal.

Sleep Disorders: Words to Know

Apnea:
A temporary pause in one's breathing pattern. Sleep apnea consists of repeated episodes of temporary pauses in breathing during sleep.
Brainstem:
Portion of the brain that connects the spinal cord to the forebrain and the cerebrum.
Cataplexy:
A sudden loss of muscular control that may cause a person to collapse.
Circadian rhythm:
Any body pattern that follows a twenty-four-hour cycle, such as waking and sleeping.
Insomnia:
Difficulty in falling asleep or in remaining asleep.
Jet lag:
A temporary disruption of the body's sleep/wake rhythm caused by high-speed air travel through different time zones.
Narcolepsy:
A sleep disorder characterized by sudden sleep attacks during the day and often accompanied by other symptoms, such as cataplexy, temporary paralysis, and hallucinations.
Polysomnograph:
An instrument used to measure a patient's body processes during sleep.
Restless leg syndrome:
A condition in which a patient experiences aching or other unpleasant sensations in the calves of the legs.
Sedative:
A substance that calms a person. Sedatives can also cause a person to feel drowsy.
Stimulant:
A substance that makes a person feel more energetic or awake. A stimulant may increase organ activity in the body.
Somnambulism:
Also called sleepwalking, it refers to a range of activities a patient performs while sleeping, from walking to carrying on a conversation.

Parasomnias

  • Nightmare disorder. Nightmare disorder is a condition in which a person is awakened from sleep by frightening dreams. Upon awakening, the person is usually fully awake. About 10 to 50 percent of children between the ages of three and five have nightmares. The condition is most likely to occur in children and adults who are under severe stress.
  • Sleep terror disorder. Sleep terror disorder occurs when a patient awakens suddenly crying or screaming. The patient may display other symptoms, such as sweating and shaking. Upon awakening, the patient may be confused or disoriented for several minutes. He or she may not remember the dream that caused the event. Sleep may return in a matter of minutes. Sleep terror disorder is common in children four to twelve years of age. The condition tends to disappear as one grows older. Less than one percent of adults have the disorder.
  • Sleepwalking disorder. Sleepwalking disorder is also called somnambulism (pronounced suhm-NAHM-byoo-LIHZ-uhm). The condition is characterized by a variety of behaviors, of which walking is only one. Sleepwalkers may also eat, use the bathroom, unlock doors, and carry on conversations. If awakened, sleepwalkers may be disoriented. They may have no memory of their sleepwalking experience. About 10 to 30 percent of children have at least one sleepwalking experience. The occurrence among adults is much lower, amounting to about 1 to 5 percent of all adults.

A few sleep disorders are related to some physical or mental disorder. The three conditions that fall into his category include:

  • Sleep disorders related to mental disorders. Many types of mental illness can cause sleep disorders. People who have severe mental illness, for example, may develop chronic (long-lasting) insomnia.
  • Sleep disorders due to physical conditions. Physical illnesses such as Parkinson's disease (see Parkinson's disease entry), encephalitis (see encephalitis entry), brain disease, and hyperthyroidism may cause sleep disorders.
  • Substance-induced sleep disorders. The use of certain types of drugs can lead to sleep disorders. The most common of these drugs are alcohol and caffeine. Certain types of medications can also cause sleep disorders. Antihistamines, steroids, and medicines used to treat asthma are examples.

CAUSES


In many cases, the cause of a sleep disorder is not known. In other cases, researchers know at least part of the reason the disorder occurs. Some examples include:

  • Insomnia. Insomnia may be caused by emotional experiences or concerns such as marital problems, problems at work, feelings of guilt, or concerns about health. A person may become so distraught that sleep is impossible. Insomnia often becomes worse when patients worry about the condition. In such cases, the worry itself becomes another cause for the disorder.
  • Hypersomnia. One possible cause of hypersomnia is restless legs syndrome. Restless legs syndrome is the name given to cramps and twitches a person may experience in the calves of the legs during sleep. These sensations may keep a person awake and lead to sleep episodes during the day.
  • Narcolepsy. The cause of narcolepsy is currently not known.
  • Sleep apnea. The most common cause of sleep apnea is blockage of the airways. The condition occurs most commonly in people who are over-weight. The snoring and gasping that are typical of apnea are caused by the person's trying to catch his or her breath. Less commonly, sleep apnea is caused by damage to the brainstem.
  • Circadian rhythm sleep disorders. Circadian rhythm sleep disorders are caused when people are forced to adjust to new dark/light patterns. An example is a worker whose assignment is changed from the day shift to the night shift. The worker must learn how to sleep when it's light out and to work when it's dark out.

The causes of most parasomnias are not well understood. In some cases, severe stress may be responsible for the condition. In other cases, it is not clear what the cause for the disorder is.

SYMPTOMS


The symptoms of most sleep disorders are obvious from the descriptions above. A person with insomnia, for example, tends to be very tired during the day. A person with nightmare disorder displays the disturbed behavior typical of a person who has been awakened from sleep by a bad dream.

DIAGNOSIS


A beginning point in diagnosing sleep disorders is an interview with the patient and his or her family. From this interview may come a list of symptoms that suggests one or another form of sleep disorder. For example, very loud snoring may be an indication that the patient has sleep apnea. Sleepwalking is, itself, enough of a symptom to permit diagnosis of the condition.

Doctors use a number of other tools to diagnose the exact type of sleep disorder a patient has experienced. Some of these tools include:

  • Sleep logs. Patients are asked to record everything about their sleep experiences they can remember. The log might include symptoms, time of appearance, severity, and frequency. Events in the person's life may also be recorded as possible clues to the cause of the disorder.
  • Psychological testing. Some sleep disorders are caused by emotional problems in a person's life. Those problems may be identified by means of certain tests. Examples of these tests are the Minnesota Multiphasic Personality Inventory (MMPI), the Beck Depression Inventory, and the Zung Depression Scale.
  • Laboratory tests. Techniques have now been developed to observe and record a patient's behavior during sleep. The most common device used is called a polysomnograph. this device measures a person's breathing, heart rate, brain waves, and other physical functions during sleep. Various types of sleep disorder can be identified based on these measurements.

TREATMENT


The choice of treatment for a sleep disorder depends on the cause of the disorder, if it is known. For example, some people develop insomnia because

they have become depressed. The solution to this problem is not to treat the insomnia, but to treat the depression (see depression entry). The patient may be given antidepressants or counseling to improve his or her emotional outlook. If this treatment is successful, the insomnia usually disappears on its own.

In many cases, however, the sleep disorder itself may be treated directly. The five forms of treatment that can be used are medications, psychotherapy, sleep education, lifestyle changes, and surgery.

Medications

One might expect that insomnia should be treated with a sedative (a substance that helps a person relax and fall asleep). But sedatives provide only temporary relief from insomnia. They do not cure the underlying cause for the disorder. In addition, some sedatives may be habit-forming or may interact with other drugs to cause serious medical problems.

Stimulants (substances that cause a person to feel more energetic or awake) are often effective in treating narcolepsy. The drug known as clonazepam is used to treat restless legs syndrome. Benzodiazepines are used for children with sleep terror disorder or sleepwalking because they help the child sleep more soundly.

Psychotherapy

Psychotherapy is used when sleep disorders are caused by emotional problems. Patients are helped to understand the nature of their problems and to find ways to solve or to live with those problems. To the extent this treatment is successful, the patient's sleep disorders may be relieved.

Sleep Education

Researchers now know a great deal about the sleep process. By learning about that process, and changing their behavior patterns, patients may overcome some forms of sleep disorder. Some general guidelines that can help people sleep better include the following:

  • Wait until you are sleepy before going to bed.
  • Avoid using the bedroom for work, reading, or watching television.
  • Get up at the same time every morning, no matter how much or how little you have slept.
  • Get at least some physical exercise every day.
  • Avoid smoking and avoid drinking liquids that contain caffeine.
  • Limit fluid intake after dinner.
  • Learn to meditate or practice relaxation techniques.
  • Do not stay in bed if you can't fall asleep. Get up and listen to relaxing music or read.

Lifestyle Changes

Some types of sleep disorders can be relieved by changing one's lifestyle. For example, people with sleep apnea should stop smoking if they smoke, avoid alcohol and drugs, and lose weight to improve the function of their airways. People who experience circadian rhythm sleep disorders should try to adjust their travel or work patterns to allow time to adjust to new day/night patterns. Children with nightmare disorder should not watch frightening movies or television programs.

Surgery

Surgery is the treatment of last resort for sleep apnea, perhaps the only type of sleep disorder that is life-threatening. Combined with other factors, such as obesity, it can cause death. In such cases, surgery may be required to open up the patient's airways and make breathing easier.

Alternative Treatment

Stress may be responsible for a number of forms of sleep disorder. Alternative treatments that teach people how to reduce stress in their lives can be very helpful. These treatments may include acupuncture, meditation, breathing exercises, yoga, and hypnotherapy. Homeopathic practitioners recommend a variety of substances to treat insomnia caused by various factors. They suggest Nux vomica for insomnia caused by alcohol or drugs, Ignatia for insomnia caused by grief, Arsenicum for insomnia caused by fear or anxiety, and Passiflora for insomnia related to mental stress.

Practitioners of Chinese medicine also have a range of herbs for the treatment of sleep disorder. The substance recommended depends on the particular type of disorder. For example, the magnetic mineral known as magnetite is recommended for insomnia caused by fear or anxiety.

Dietary changes may also help relieve some sleep disorders. Patients should avoid any food that contains caffeine or other stimulants. Such foods include coffee, tea, cola drinks, and chocolate. Some botanical remedies that may help a person relax and get a good night's sleep include valerian, passionflower, and skullcap.

PROGNOSIS


Prognosis depends on the specific type of sleep disorder. In most cases, children outgrow sleep disorders such as nightmares and sleep terror disorder. Other conditions tend to be chronic. Narcolepsy, for example, is a life-long condition. Relatively few forms of sleep disorder represent life-threatening medical conditions. Sleep apnea is one of the few examples.

See also: Insomnia.

FOR MORE INFORMATION


Books

Albert, Katherine A. Get a Good Night's Sleep. New York: Simon & Schuster, 1996.

Borysenko, Joan. Minding the Body, Mending the Mind. Reading, MA: Addison-Wesley Publishing Company, 1987.

Kabat-Zinn, Jon. Full Catastrophe Living: Using the Wisdom of Your Body and Mind to Face Stress, Pain, and Illness. New York: Bantam Doubleday Dell Publishing Group, 1990.

Zammit, Gary. Good Nights: How to Stop Sleep Deprivation, Overcome Insomnia, and Get the Sleep You Need. Kansas City, MO: Andrews McMeel Publishing, 1998.

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Sleep Disorders

Sleep Disorders

Why Are Sleep Disorders Important?

What Is Normal Sleep?

What Are the Types and the Stages of Sleep?

How Do Doctors Diagnose and Treat Sleep Disorders?

Guidelines for Prevention

Resources

A sleep disorder is just what its name implies: something abnormal about the way a person is sleeping. It might be that he or she cannot get enough sleepy as is the case in insomnia (in-SOM-nee-a). In hypersomnia (HY-per-SOM-nee-a), the individual sleeps too much. In still other kinds of sleep disorders, events such as night terrors may interfere with sleep.

KEYWORDS

for searching the Internet and other reference sources

Dreams

Somnambulism

Why Are Sleep Disorders Important?

When people do not get a normal refreshing sleep, they are not at their best. They may be impatient or careless, or they may show poor judgment in the things they do. They also may be irritable with family and friends. Sleeplessness can cause serious accidents, as when someone nods off while driving a car or operating machinery.

An estimated 30 million to 40 million Americans have serious sleep problems that can be damaging to their health. In the case of insomnia alone, estimates of the cost in terms of lost productivity reach many billions of dollars.

In order to understand sleep disorders, it is necessary to understand something about sleep itself and the wide range of normal variations in the way people sleep.

What Is Normal Sleep?

On average, about one-third of a persons life is spent sleeping. However, the amount and timing of sleep vary considerably in different people, based on their age and lifestyle. Newborn infants may sleep up to 20 hours a day. Young and middle-aged adults sleep about 8 hours on average. Elderly people tend to get less sleep at night but may take naps during the day.

The timing of sleep often is determined by such factors as work schedules, but it is affected by lifestyle as well. Some individuals seem to be morning people, or early birds, by nature, whereas others are night owls, preferring to stay up late.

What Are the Types and the Stages of Sleep?

Scientists at sleep laboratories have discovered that there are two distinct types of sleep. One is called rapid eye movement, or REM, sleep, because the eyes can be seen moving rapidly beneath the closed eyelids. Dreaming takes place during REM sleep, and the brain waves of someone in REM sleep look much like those of someone who is awake when the waves are measured on an electroencephalogram (ee-LEK-tro-en-SEF-a-lo-gram), or EEG.

The other type is non-REM sleep. It consists of four stages in which the brain waves progressively become deeper and slower but then speed up again until the REM stage occurs. This cycle normally is repeated with some variation at approximately 90-minute intervals, with REM sleep usually taking up about 25 percent of the total.

Studies conducted at sleep laboratories have contributed greatly to the diagnosis and treatment of sleep problems. The following are some of the more common sleep disorders.

Insomnia

Insomnia is a general term for trouble sleeping (somnia comes from the Latin sornnus, which means sleep). The disorder is very common, as can be inferred from the fact that sleeping pills are among the most widely used of all medications. People with insomnia may have difficulty falling asleep, or they may wake up too early in the morning. Some wake up frequently during the night and then find it hard to go back to sleep.

Because people need different amounts of sleep, insomnia is not defined by hours of sleep. Insomnia is classified according to how long it lasts. Transient, or short-term, insomnia lasts from one night to a few weeks. Causes may include stress, excitement, or a change in surroundings. Chronic* insomnia, which occurs almost every night for a month or more, is a complex disorder with multiple causes.

* chronic
(KRON-ik) means Continuing for a long period of time.

Sleep apnea

A person with sleep apnea (AP-nee-a) stops breathing intermittently while asleep, for periods of about 10 seconds or more. The most common and severe type is obstructive sleep apnea. In this disorder, the muscles at the back of the throat relax and sag during sleep, until they obstruct the airway. The pressure to breathe builds up until the sleeper gasps for air. These episodes may occur hundreds of times a night and are accompanied by wakings so brief that they usually are not remembered. People with sleep apnea typically complain of being very tired during the day. Severe sleep apnea can induce high blood pressure and increase the risk of stroke*, heart attack, and even heart failure.

* stroke
is a blocked or ruptured blood vessel within the brain, which deprives some brain cells of oxygen and thereby kills or damages these cells. Also called apoplexy (AP-o-plek-see).

Narcolepsy

Narcolepsy (NAR-ko-lep-see), like sleep apnea, involves excessive daytime sleepiness. In narcolepsy, however, the person cannot resist falling asleep. Sleep attacks crop up at odd and inappropriate times, such as while eating or talking to someone. Another symptom is cataplexy (KAT-a-plek-see), a sudden attack of muscular weakness that can make the person go limp and fall. Some people with narcolepsy also experience frightening hallucinations* or sleep paralysis*, an inability to move or speak, while falling asleep or waking up. Research has shown that during a sleep attack, the REM stage of sleep intrudes suddenly into the waking state. Narcolepsy is a lifelong condition of unknown cause. Narcoplesy does run in families. Sometimes socially embarrassing or inconvenient, this disorder can also be severely disabling and cause injury.

* hallucinations
(ha-loo-si-NAY-shunz) are sensory perceptions without a cause in the outside world.
* paralysis
(pa-RAL-i-sis) is the loss or impairment of the ability to move some part of the body.

Hypersomnia People with hypersomnia may sleep excessively during the day or longer than normal at night. Drowsiness or sleep periods last longer than with narcolepsy. Psychological depression* often is the main cause. A rare type of hypersomnia called Kleine-Levin syndrome* is characterized by periods of overeating as well as oversleeping. It occurs most often in teenage boys.

* depression
(de-PRESH-un) is a mental state characterized by feelings of sadness, despair, and discouragement.
* syndrome
means a group or pattern of symptoms that occur together.

Jet lag When an air traveler crosses several time zones, jet lag occurs. The bodys internal clock then is desynchronized (or out of sync) with local time. Temporarily, people with jet lag may find it difficult to stay awake during the day or be unable to sleep at night.

Nightmares Almost everyone has nightmares occasionally. These unpleasant, vivid dreams occur during REM sleep, usually in the middle or late hours of the night. Upon awakening, the dreamer often remembers the nightmare clearly and may feel anxious. Nightmares are especially common in young children. In adults, they may be a side effect of certain drugs or of traumatic events, such as accidents.

The Poets on Sleep and Sleep Disorders

William Shakespeare expressed in poetic terms the value and purpose of sleep when he wrote, Sleep that knits up the ravelld sleave of care,/The death of each days life, sore labours bath,/Balm of hurt minds, great natures second course,/Chief nourisher in lifes feast (Macbeth, Act II, Scene 2).

In modern times, the humorous poet Ogden Nash, who delighted in creating whimsical rhymes, showed familiarity with sleep problems in this verse: Sleep is perverse as human nature,/Sleep is as perverse as a legislature,/Sleep is as forward as hives or goiters,/And where it is least desired, it loiters {The Face Is Familiar. Read This Vibrant Exposé).

Night terrors and sleepwalking A night terror is quite different from a nightmare. It occurs in children during deep non-REM sleep, usually an hour or two after going to bed. During an episode, they may sit up in bed shrieking and thrashing about with their eyes wide open. Typically, the next day they remember nothing of the event. Night terrors occur chiefly in preschool children. Although frightening, they generally are harmless and are soon outgrown.

Melatonin

Some over-the-counter sleep aids contain melatonin (mel-a-TO-nin). Melatonin is a hormone secreted during darkness by the pineal (PIN-e-al) gland, a small structure located over the brain stem*.

* brain stem
is the part of the brain that connects to the spinal cord. The brain stem controls the basic functions of life, such as breathing and blood pressure.

Melatonin appears to be part of the system that regulates our sleep-wake cycles. Some research studies have shown that a small dose of melatonin at night helps make falling asleep easier, and that melatonin may be beneficial to travelers who have jet lag.

Melatonin is available for sale without a prescription, but the U.S. Food and Drug Administration does not regulate its production or sale. Studies still are being conducted to determine whether melatonin is safe for use.

Sleepwalking also occurs during non-REM sleep. It was once believed to be the acting out of dreams, but this is not the case. It takes place most commonly in children. The sleepwalker wanders about aimlessly, appearing dazed and uncoordinated, and remembers nothing of the episode afterward.

How Do Doctors Diagnose and Treat Sleep Disorders?

Most sleep disorders can be treated successfully if diagnosed properly. Anyone who sleeps poorly for more than a month or has daytime sleepiness that interferes with normal activities may wish to consult a doctor or be referred to a specialist in sleep disorders.

At a sleep clinic, patients first are asked questions about their medical history and sleep history. A polysomnogram (pol-ee-SOM-no-gram) is sometimes used to measure brain waves, muscle activity, breathing, and other body functions during sleep.

Many sleep disorders, such as jet lag, short-term insomnia, and most nightmares, do not need treatment. Some others, such as night terrors, are outgrown.

Chronic insomnia often is treated successfully with behavior therapy, which involves various relaxation techniques and reconditioning to change poor sleeping habits. Sleeping pills may be used temporarily, but their long-term use is controversial because of unwanted side effects.

Obstructive sleep apnea often is treated with dental appliances or a device known as CPAP (continuous positive airway pressure) to keep the airway open. Operations sometimes are performed to treat severe obstructive sleep apnea.

Hypersomnia due to depression is often helped by psychotherapy*.

* psychotherapy
(SY-ko-THER-a-pee) is the treatment of mental and behavioral disorders by support and insight to encourage healthy behavior patterns and personality growth.

There is no cure for narcolepsy, but medications can help control or ease symptoms.

Guidelines for Prevention

Most sleep disorders can be prevented or minimized by making a few changes in ones lifestyle. The following are some simple guidelines:

  • Avoid excessive amounts of caffeine or alcoholic beverages, especially soon before bedtime. The same goes for smoking cigarettes. Avoid frequently disrupted sleep-wake schedules.
  • Avoid excessive napping in the afternoon or evening.
  • Exercise regularly, but not just before retiring.

Did You Know?

  • Our eyes move when we dream much as they do when we are awake.
  • A person who lived to be 70 would spend about 6 years dreaming.
  • In one sleep disorder, apnea, people can stop breathing hundreds of times each night.
  • In another, narcolepsy, someone can fall asleep while having a conversation.
  • Night terrors are different from nightmares.
  • People who sleepwalk are not acting out their dreams.

See also

Insomnia

Jet Lag

Sleep Apnea

Resources

Book

Remmes, Ann, and Roxanne Nelson. If You Think You Have a Sleep Disorder. New York: Dell Publishing Co., 1998.

Organizations

The National Heart, Lung, and Blood Institute (NHLBI), part of the U.S. National Institutes of Health (NIH), posts information about insomnia on its website. http://www.nhlbi.nih.gov/health/public/sleep/insomnia.htm

The National Institute of Neurological Disorders and Stroke (NINDS), part of the U.S. National Institutes of Health (NIH), posts information about sleeping disorders on its website. http://www.ninds.nih.gov/patients/Disorder/SLEEP/brain-basics-sleep.htm

The National Sleep Foundation posts a fact sheet, The Nature of Sleepy on its website. http://www.sleepfoundation.org/publications/nos.html

Center for Narcolepsy Research (CNR), College of Nursing, The University of Illinois at Chicago, 845 South Damen Avenue, Room 215, Chicago, IL 60612-7350. CNR posts information about narcolepsy on its website. Telephone 312-996-5176 http://www.uic.edu/depts/cnr

The Nemours Foundation posts a fact sheet, Coping with Night Terrors, on its website. http://kidshealth.org/parent/behavior/nghtter.html

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Sleep Disorders

Sleep Disorders

Definition

Sleep disorders are a group of syndromes characterized by disturbance in a person's amount of sleep, quality or timing of sleep, or in behaviors or physiological conditions associated with sleep. There are about 70 different sleep disorders. To qualify for the diagnosis of sleep disorder, the condition must be a persistent problem, cause an individual significant emotional distress, and interfere with social or occupational functioning. The text revision of the fourth edition (2000) of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV-TR) specifically excludes temporary disruptions of sleeping patterns caused by travel or other short-term stresses.

Although sleep is a basic behavior in animals as well as humans, researchers still do not completely understand all of its functions in maintaining health. In the past 30 years, however, laboratory studies on human volunteers have yielded new information about the different types of sleep. Researchers have learned about the cyclical patterns of different types of sleep and their relationships to breathing, heart rate, brain waves, and other physical functions. These measurements are obtained by a technique called polysomnography.

There are five stages of human sleep. Four stages have non-rapid eye movement (NREM) sleep, with unique brain wave patterns and physical changes occurring. Dreaming occurs in the fifth stage, during rapid eye movement (REM) sleep.

  • Stage 1 NREM sleep. This stage occurs while a person is falling asleep. It represents about 5% of a normal adult's sleep time.
  • Stage 2 NREM sleep. In this stage, (the beginning of "true" sleep), the person's electroencephalogram (EEG) will show distinctive wave forms called sleep spindles and K complexes. About 50% of sleep time is stage 2 NREM sleep.
  • Stages 3 and 4 NREM sleep. Also called delta or slow wave sleep, these are the deepest levels of human sleep and represent 10-20% of sleep time. They usually occur during the first 30-50% of the sleeping period.
  • REM sleep. REM sleep accounts for 20-25% of total sleep time. It usually begins about 90 minutes after a person falls asleep, an important measure called REM latency. It alternates with NREM sleep about every hour and a half throughout the night. REM periods increase in length over the course of the night.

Sleep cycles vary with a person's age. Children and adolescents have longer periods of stage 3 and stage 4 NREM sleep than do middle aged or elderly adults. Because of this difference, a doctor will need to take a person's age into account when evaluating a sleep disorder. Total REM sleep also declines with age.

The average length of nighttime sleep varies among people. Most individuals sleep between seven and nine hours a night. This population average appears to be constant throughout the world. In temperate climates, however, people often notice that sleep time varies with the seasons. It is not unusual for people in North America and Europe to sleep about 40 minutes longer per night during the winter.

Description

The DSM-IV-TR classifies sleep disorders based on their causes. Primary sleep disorders are distinguished from those that are not caused by other mental disorders, prescription medications, substance abuse, or medical conditions. The two major categories of primary sleep disorders are the dyssomnias and the parasomnias.

Dyssomnias

Dyssomnias are primary sleep disorders in which a person suffers from changes in the amount, restfulness, and timing of sleep. The most important dyssomnia is primary insomnia, which is defined as difficulty in falling asleep or remaining asleep that lasts for at least one month. It is estimated that 35% of adults in the United States experience insomnia during any given year, but the number of these adults who are experiencing true primary insomnia is unknown. Primary insomnia can be caused by a traumatic event related to sleep or bedtime, and it is often associated with increased physical or psychological arousal at night. People who experience primary insomnia are often anxious about not being able to sleep. Individuals may then associate all sleep-related things (their bed, bedtime, etc.) with frustration, making the problem worse. They then become more stressed about not sleeping. Primary insomnia often begins in young adulthood or in middle age.

Hypersomnia is a condition marked by excessive sleepiness during normal waking hours. Affected persons either have lengthy episodes of daytime sleep or episodes of daytime sleep on a daily basis even though they are sleeping normally at night. In some cases, persons with primary hypersomnia have difficulty waking in the morning and may appear confused or angry. This condition is sometimes called sleep drunkenness and is more common in males. The number of people with primary hypersomnia is unknown, although 5-10% of people in sleep disorder clinics have the disorder. Primary hypersomnia usually affects young adults between the ages of 15 and 30.

Nocturnal myoclonus and restless legs syndrome (RLS) can cause either insomnia or hypersomnia in adults. Individuals with nocturnal myoclonus wake up because of cramps or twitches in the calves. These people feel sleepy the next day. Nocturnal myoclonus is sometimes called periodic limb movement disorder. RLS patients have a crawly or aching feeling in their calves that can be relieved by moving or rubbing the legs. RLS often prevents people from falling asleep until the early hours of the morning, when the condition is less intense.

Kleine-Levin syndrome is a recurrent form of hypersomnia that affects a person three or four times a year. Doctors do not know the cause of this syndrome. It is marked by two to three days of sleeping 18-20 hours per day, hypersexual behavior, compulsive eating, and irritability. Men are three times more likely than women to have the syndrome. There is no cure for this disorder.

Narcolepsy is a dyssomnia characterized by recurrent "sleep attacks" that a person cannot fight. The sleep attacks are about 10-20 minutes long. A person feels refreshed by the sleep, but typically feels sleepy again several hours later. Narcolepsy has three major symptoms in addition to sleep attacks: cataplexy, hallucinations, and sleep paralysis. Cataplexy is the sudden loss of muscle tone and stability ("drop attacks"). Hallucinations may occur just before falling asleep (hypnagogic) or right after waking up (hypnopompic) and are associated with an episode of REM sleep. Sleep paralysis occurs during the transition from being asleep to waking up. About 40% of patients with narcolepsy have or have had another mental disorder. Although narcolepsy is often regarded as an adult disorder, it has been reported in children as young as three years old. Almost 18% of people with narcolepsy are 10 years old or younger. It is estimated that 0.02-0.16% of the general population suffers from narcolepsy. Men and women are equally affected.

Breathing-related sleep disorders are syndromes in which a person's sleep is interrupted by problems with breathing. There are three types of breathing-related sleep disorders:

  • Obstructive sleep apnea syndrome. This is the most common form of breathing-related sleep disorder, marked by episodes of blockage in the upper airway during sleep. It is found primarily in obese people. Persons with this disorder typically alternate between periods of snoring or gasping (when their airway is partly open) and periods of silence (when their airway is blocked). Very loud snoring is a clue to this disorder.
  • Central sleep apnea syndrome. This disorder is primarily found in elderly people with heart or neurological conditions that affect their ability to breathe properly. It is not associated with airway blockage and may be related to brain disease.
  • Central alveolar hypoventilation syndrome. This disorder is found most often in extremely obese people. Their airway is not blocked, but blood oxygen level is too low.
  • Mixed-type sleep apnea syndrome. This disorder combines symptoms of both obstructive and central sleep apnea.

Circadian rhythm sleep disorders are dyssomnias resulting from a discrepancy between a person's daily sleep and wake patterns and demands of social activities, shift work, or travel. The term circadian comes from a Latin word meaning daily. There are three circadian rhythm sleep disorders. Delayed sleep phase type is characterized by going to bed and arising later than most people. Jet lag type is caused by travel to a new time zone. Shift work type is caused by the schedule of a person's job. People who are ordinarily early risers appear to be more vulnerable to jet lag and shift work-related circadian rhythm disorders than people who are "night owls." There are some individuals who do not fit the pattern of these three disorders and appear to be the opposite of the delayed sleep phase type. These people have an advanced sleep phase pattern and cannot stay awake in the evening, but wake up on their own in the early morning.

PARASOMNIAS. Parasomnias are primary sleep disorders in which a person's behavior is affected by specific sleep stages or transitions between sleeping and waking. They are sometimes described as disorders of physiological arousal during sleep.

Nightmare disorder is a parasomnia in which a person is repeatedly awakened from sleep by frightening dreams and is fully alert on awakening. The actual rate of occurrence of nightmare disorder is unknown. Approximately 10-50% of children between three and five years old experience nightmares. They occur during REM sleep, usually in the second half of the night. A child is usually able to remember the content of the nightmare and may be afraid to go back to sleep. More females than males have this disorder, but it is not known whether the gender difference reflects a difference in occurrence or a difference in reporting. Nightmare disorder is most likely to occur in children or adults under severe or traumatic stress.

Sleep terror disorder is a parasomnia in which a person awakens screaming or crying. The individual also has physical signs of arousal, like sweating, shaking, etc. It is sometimes referred to as pavor nocturnus. Unlike nightmares, sleep terrors typically occur in stage 3 or stage 4 NREM sleep during the first third of the night. A person may be confused or disoriented for several minutes and cannot recall the content of the dream. There is usually a return to sleep without being able to remember the episode the next morning. Sleep terror disorder is most common in children four to 12 years old and is outgrown in adolescence. It affects about 3% of children. Fewer than 1% of adults have the disorder. In adults, it usually begins between the ages of 20 and 30. In children, more males than females have the disorder. In adults, men and women are equally affected.

Sleepwalking disorder, which is sometimes called somnambulism, occurs when a person is capable of complex movements during sleep, including walking. Like sleep terror disorder, sleepwalking occurs during stage 3 and stage 4 NREM sleep during the first part of the night. If individuals are awakened during a sleepwalking episode, they may be disoriented and have no memory of the behavior. In addition to walking around, persons with sleepwalking disorder have been reported to eat, use the bathroom, unlock doors, or talk to others. It is estimated that 10-30% of children have at least one episode of sleepwalking. However, only 1-5% meet the criteria for sleepwalking disorder. The disorder is most common in children eight to 12 years old. It is unusual for sleepwalking to occur for the first time in adults.

Unlike sleepwalking, REM sleep behavior disorder occurs later in the night and people can remember what they were dreaming. The physical activities of such persons are often violent.

Sleep disorders related to other conditions

In addition to the primary sleep disorders, the DSM-IV-TR specifies three categories of sleep disorders that are caused by or related to substance use or other physical or mental disorders.

Many mental disorders, especially depression or one of the anxiety disorders, can cause sleep disturbances. Psychiatric disorders are the most common cause of chronic insomnia.

Some people with chronic neurological conditions like Parkinson's disease or Huntington's disease may develop sleep disorders. Sleep disorders have also been associated with viral encephalitis, brain disease, and hypo- or hyperthyroidism.

The use of drugs, alcohol, and caffeine frequently produce disturbances in sleep patterns. Alcohol abuse is associated with insomnia. A person may initially feel sleepy after drinking, but wakes up or sleeps fitfully during the second half of the night. Alcohol can also increase the severity of breathing-related sleep disorders. With amphetamines or cocaine, a person typically suffers from insomnia during drug use and hypersomnia during drug withdrawal. Opioids usually make short-term users sleepy. However, long-term users develop tolerance and may suffer from insomnia.

In addition to alcohol and drugs that are abused, a variety of prescription medications can affect sleep patterns. These medications include antihistamines, corticosteroids, asthma medicines, and drugs that affect the central nervous system.

Sleep disorders in children and adolescents

Pediatricians estimate that 20-30% of children have difficulties with sleep that are serious enough to disturb their families. Although sleepwalking and night terror disorder occur more frequently in children than in adults, children can also suffer from narcolepsy and sleep apnea syndrome.

Causes and symptoms

The causes of sleep disorders have already been discussed with respect to the DSM-IV-TR classification of these disorders.

The most important symptoms of sleep disorders are insomnia and sleepiness during waking hours. Insomnia is by far the more common of the two symptoms. It covers a number of different patterns of sleep disturbance. These patterns include inability to fall asleep at bedtime, repeated awakening during the night, and/or inability to go back to sleep once awakened.

Diagnosis

Diagnosis of sleep disorders usually requires a psychological history as well as a medical history. With the exception of sleep apnea syndromes, physical examinations are not usually revealing. A person's gender and age are useful starting points in assessing the problem. A doctor may also talk to other family members to obtain information about a person's symptoms. A family's observations are particularly important to evaluate sleepwalking, kicking in bed, snoring loudly, or other behaviors that an individual cannot remember.

Sleep logs

Many doctors ask people to keep a sleep diary or sleep log for a minimum of one to two weeks in order to evaluate the severity and characteristics of the sleep disturbance. An individual records medications taken as well as the length of time spent in bed, the quality of the sleep, and similar information. Some sleep logs are designed to indicate circadian sleep patterns as well as simple duration or restfulness of sleep.

Psychological testing

A physician may use psychological tests or inventories to evaluate insomnia because it is frequently associated with mood or affective disorders. The Minnesota Multiphasic Personality Inventory (MMPI), the Millon Clinical Multiaxial Inventory (MCMI), the Beck Depression Inventory, and the Zung Depression Scale are the tests most commonly used in evaluating this symptom.

Self-report tests

The Epworth Sleepiness Scale, a self-rating form recently developed in Australia, consists of eight questions used to assess daytime sleepiness. Scores range from 0-24, with scores higher than 16 indicating severe daytime sleepiness.

Laboratory studies

If a doctor is considering breathing-related sleep disorders, myoclonus, or narcolepsy as possible diagnoses, an affected person may be tested in a sleep laboratory or at home with portable instruments.

POLYSOMNOGRAPHY. Polysomnography can be used to help diagnose sleep disorders as well as conduct research into sleep. In some cases a person is tested in a special sleep laboratory. The advantage of this testing is the availability and expertise of trained technologists, but it is expensive. Portable equipment is available for home recording of certain specific physiological functions.

MULTIPLE SLEEP LATENCY TEST. The multiple sleep latency test (MSLT) is frequently used to measure the severity of a person's daytime sleepiness. The test measures sleep latency (the speed with which an individual falls asleep) during a series of planned naps during the day. The test also measures the amount of REM sleep that occurs. Two or more episodes of REM sleep under these conditions indicates narcolepsy. This test can also be used to help diagnose primary hypersomnia.

REPEATED TEST OF SUSTAINED WAKEFULNESS. The repeated test of sustained wakefulness (RTSW) measures sleep latency by challenging a person's ability to stay awake. In the RTSW, a person is placed in a quiet room with dim lighting and is asked to stay awake. As with the MSLT, the testing pattern is repeated at intervals during the day.

Treatment

Treatment for a sleep disorder depends on what is causing the disorder. For example, if major depression is the cause of insomnia, then treatment of the depression with antidepressants should resolve the insomnia.

Medications

Sedative or hypnotic medications are generally recommended only for insomnia related to a temporary stress (such as surgery or grief) because of the potential for addiction or overdose. Trazodone, a sedating antidepressant, is often used for chronic insomnia that does not respond to other treatments. Sleep medications may also cause problems for elderly persons because of possible interactions with their other prescription medications. Among the safer hypnotic agents are lorazepam, temazepam, and zolpidem. Chloral hydrate is often preferred for short-term treatment in elderly people because of its mildness. Short-term treatment is recommended because this drug may be habit forming.

Narcolepsy is treated with stimulants such as dextroamphetamine sulfate or methylphenidate. Nocturnal myoclonus has been successfully treated with clonazepam.

Children with sleep terror disorder or sleepwalking are usually treated with benzodiazepines because this type of medication suppresses stage 3 and stage 4 NREM sleep.

Psychotherapy

Psychotherapy is recommended for persons with sleep disorders associated with other mental disorders. In many cases an individual's scores on the Beck or Zung inventories will suggest the appropriate direction of treatment.

Sleep education

"Sleep hygiene" or sleep education for sleep disorders often includes instructing a person in methods to enhance sleep. People are advised to:

  • Wait until they feel sleepy before going to bed.
  • Avoid using the bedroom for work, reading, or watching television.
  • Get up at the same time every morning no matter how much or how little they have slept.
  • Avoid smoking and avoid drinking liquids with caffeine.
  • Get some physical exercise on a daily basis, early in the day.
  • Limit fluid intake after dinner; in particular, avoid alcohol because it frequently causes interrupted sleep.
  • Learn to meditate or practice relaxation techniques.
  • Avoid tossing and turning in bed; instead, people should get up and listen to relaxing music or read.

Lifestyle changes

People with sleep apnea or hypopnea are encouraged to stop smoking, avoid alcohol or drugs of abuse, and lose weight in order to improve the stability of the upper airway.

In some cases, individuals with sleep disorders related to jet lag or shift work may need to change employment or travel patterns. They may need to avoid rapid changes in shifts at work.

Children with nightmare disorder may benefit from limits on television or movies. Violent scenes or frightening science fiction stories appear to influence the frequency and intensity of children's nightmares.

Surgery

Although making a surgical opening into the windpipe (a tracheostomy) for sleep apnea or hypopnea in adults is a treatment of last resort, it is occasionally performed if a person's disorder is life threatening and cannot be treated by other methods. In children and adolescents, surgical removal of the tonsils and adenoids is a fairly common and successful treatment for sleep apnea. Most people with sleep apnea are treated with continuous positive airway pressure (CPAP). Sometimes an oral prosthesis is used for mild sleep apnea.

Alternative treatment

Some alternative approaches may be effective in treating insomnia caused by anxiety or emotional stress. Meditation practice, breathing exercises, and yoga can break the vicious cycle of sleeplessness, worry about inability to sleep, and further sleeplessness for some people. Yoga can help some people to relax muscular tension in a direct fashion. The breathing exercises and meditation can keep them from obsessing about sleep.

Homeopathic practitioners recommend that people with chronic insomnia see a professional homeopath. They do, however, prescribe specific remedies for at-home treatment of temporary insomnia: Nux vomica for alcohol or substance-related insomnia, Ignatia for insomnia caused by grief, Arsenicum for insomnia caused by fear or anxiety, and Passiflora for insomnia related to mental stress.

Melatonin has also been used as an alternative treatment for sleep disorders. Melatonin is produced in the body by the pineal gland at the base of the brain. This substance is thought to be related to the body's circadian rhythms.

Practitioners of Chinese medicine usually treat insomnia as a symptom of excess yang energy. Cinnabar is recommended for chronic nightmares. Either magnetic magnetite or "dragon bones" is recommended for insomnia associated with hysteria or fear. If the insomnia appears to be associated with excess yang energy arising from the liver, a practitioner will suggest oyster shells. Acupuncture treatments can help bring about balance and facilitate sleep.

Dietary changes such as eliminating stimulant foods (coffee, cola, chocolate) and late-night meals or snacks can be effective in treating some sleep disorders. Nutritional supplementation with magnesium, as well as botanical medicines that calm the nervous system, can also be helpful. Among the botanical remedies that may be effective for sleep disorders are valerian (Valeriana officinalis), passionflower (Passiflora incarnata), and skullcap (Scutellaria lateriflora).

KEY TERMS

Apnea— The temporary absence of breathing. Sleep apnea consists of repeated episodes of temporary suspension of breathing during sleep.

Cataplexy— Sudden loss of muscle tone (often causing a person to fall), usually triggered by intense emotion. It is regarded as a diagnostic sign of narcolepsy.

Circadian rhythm— Any body rhythm that recurs in 24-hour cycles. The sleep-wake cycle is an example of a circadian rhythm.

Dyssomnia— A primary sleep disorder in which the patient suffers from changes in the quantity, quality, or timing of sleep.

Electroencephalogram (EEG)— The record obtained by a device that measures electrical impulses in the brain.

Hypersomnia— An abnormal increase of 25% or more in time spent sleeping. Patients usually have excessive daytime sleepiness.

Hypnotic— A medication that makes a person sleep.

Hypopnea— Shallow or excessively slow breathing usually caused by partial closure of the upper airway during sleep, leading to disruption of sleep.

Insomnia— Difficulty in falling asleep or remaining asleep.

Jet lag A temporary disruption of the body's sleep-wake rhythm following high-speed air travel across several time zones. Jet lag is most severe in people who have crossed eight or more time zones in 24 hours.

Kleine-Levin syndrome— A disorder that occurs primarily in young males, three or four times a year. The syndrome is marked by episodes of hypersomnia, hypersexual behavior, and excessive eating.

Narcolepsy— A life-long sleep disorder marked by four symptoms: sudden brief sleep attacks, cataplexy, temporary paralysis, and hallucinations. The hallucinations are associated with falling asleep or the transition from sleeping to waking.

Nocturnal myoclonus— A disorder in which the patient is awakened repeatedly during the night by cramps or twitches in the calf muscles. Nocturnal myoclonus is sometimes called periodic limb movement disorder (PLMD).

Non-rapid eye movement (NREM) sleep— A type of sleep that differs from rapid eye movement (REM) sleep. The four stages of NREM sleep account for 75-80% of total sleeping time.

Parasomnia— A primary sleep disorder in which a person's physiology or behaviors are affected by sleep, the sleep stage, or the transition from sleeping to waking.

Pavor nocturnus— Another term for sleep terror disorder.

Polysomnography— Laboratory measurement of a person's basic physiological processes during sleep. Polysomnography usually measures eye movement, brain waves, and muscular tension.

Primary sleep disorder— A sleep disorder that cannot be attributed to a medical condition, another mental disorder, or prescription medications or other substances.

Rapid eye movement (REM) sleep— A phase of sleep during which a person's eyes move rapidly beneath the lids. It accounts for 20-25% of sleep time. Dreaming occurs during REM sleep.

REM latency— After a person falls asleep, the amount of time it takes for the first onset of REM sleep.

Restless legs syndrome (RLS)— A disorder in which a person experiences crawling, aching, or other disagreeable sensations in the calves that can be relieved by movement. RLS is a frequent cause of difficulty falling asleep at night.

Sedative— A medication given to calm agitated individuals; sometimes used as a synonym for hypnotic.

Sleep latency— The amount of time that it takes to fall asleep. Sleep latency is measured in minutes and is important in diagnosing depression.

Somnambulism— Another term for sleepwalking.

Prognosis

Prognosis depends on the specific disorder. Children usually outgrow sleep disorders. People with Kleine-Levin syndrome usually get better by age 40. Narcolepsy is a life-long disorder. The prognosis for sleep disorders related to other conditions depends on successful treatment of the substance abuse, medical condition, or other mental disorder. The prognosis for primary sleep disorders is affected by many things, including a person's age, gender, occupation, personality characteristics, family circumstances, neighborhood environment, and similar factors.

Health care team roles

Sleep experts are often trained in physiology, medicine or psychology. Such professionals often administer tests and make initial diagnoses. Physicians prescribe drugs for some forms of sleep disorders. Surgeons are occasionally called upon for surgical intervention. Nurses take part in any testing as well as providing pre-test patient education. Family members are often key members of a health care team when they provide information and help to make changes in the home. An affected person may become a member of the health care team when making dietary modifications, seeking alternative employment or deciding to undertake a course of therapy.

Prevention

Sleep disorders are difficult to prevent. Recognition of potential causes and avoidance of such situations or substances can prevent many forms of sleep disorders. Since many sleep disorders are relatively common and transitory, a good attitude about occasional problems with sleep is very helpful. This can prevent worrying.

Resources

BOOKS

American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders DSM-IV-TR. Chicago: American Psychiatric Association Press, 2000.

Culebras, Antonio. Sleep Disorders and Neurological Disease. New York: Marcel Dekker, 1999.

Dement, William, and Christopher Vaughn. The Promise of Sleep. New York: Delacorte Press, 1999.

Jenkins, Renee R. "Sleep disorders." In Nelson Textbook of Pediatrics, 16th ed., edited by Richard E. Behrman et al. Philadelphia: Saunders, 2000, 572.

Rosen, Carol L., and Gabriel G. Haddad. "Obstructive sleep apnea and hypoventilation in children." In Nelson Textbook of Pediatrics, 16th ed., edited by Richard E. Behrman et al. Philadelphia: Saunders, 2000, 1268-1271.

Shneerson, John. Handbook of Sleep Medicine. New York: Blackwell, 2000.

Simon, Roger, and Maria Sunseri. "Disorders of sleep and arousal." In Cecil Textbook of Medicine, 21st Ed., edited by Goldman, Lee Goldman and Bennett, J. Claude. Philadelphia: Saunders, 2000.

Thorpy, Michael, and Jan Yager. The Encyclopedia of Sleep and Sleep Disorders, 2nd Ed. New York: Facts on File, 2001.

PERIODICALS

Phillips, B., Ancoli-Israel, S. "Sleep disorders in the elderly." Sleep Medicine 2, no. 2 (2001): 99-114.

Richards, K. C., O'Sullivan, P. S., Phillips, R. L. "Measurement of sleep in critically ill patients." Journal of Nursing Measurement 8, no. 2 (2000): 131-144.

Santiago, J. R., Nolledo, M. S., Kinzler, W., Santiago, T. V. "Sleep and sleep disorders in pregnancy." Annals of Internal Medicine 134, no. 5 (2001): 396-408.

Sateia, M. J., Greenough, G., Nowell, P. "Sleep in neuropsychiatric disorders." Seminars in Clinical Neuropsychiatry 5, no. 4 (2000): 227-237.

Werra, R. "Restless legs syndrome." American Family Physician 63, no. 6 (2001): 1048.

ORGANIZATIONS

American Academy of Neurology. 1080 Montreal Avenue, St. Paul, Minnesota 55116, (651) 695-1940, 〈http://www.aan.com/resources.html,〉 [email protected]

American Academy of Sleep Medicine. 6301 Bandel Road NW, Suite 101, Rochester, MN 55901. (507) 287-6006. Fax: (507) 287-6008, 〈http://www.asda.org/,〉[email protected]

American Psychiatric Association. 1400 K Street NW, Washington, DC 20005. (888) 357-7924. Fax: (202) 682-6850. 〈http://www.psych.org/,〉 [email protected]

OTHER

Columbia Presbyterian Medical Center. 〈http://cpmcnet.columbia.edu/dept/sleep/〉.

Mayo Clinic. 〈http://www.mayo.edu/geriatrics-rst/Sleep_ToC.html〉.

National Institutes of Health, National Center on Sleep Disorders Research. 〈http://www.nhlbi.nih.gov/about/ncsdr/index.htm〉.

National Library of Medicine. 〈http://www.nlm.nih.gov/medlineplus/sleepdisorders.html〉.

Sleep Medicine Home Page. 〈http://www.users.cloud9.net/∼thorpy/〉.

University of Washington School of Medicine. 〈http://depts.washington.edu/otoweb/sleepapnea.html〉.

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Sleep Disorders

Sleep Disorders

Definition

Description

Causes and symptoms

Demographics

Diagnosis

Treatments

Prognosis

Prevention

Resources

Definition

Sleep disorders are conditions that interfere with the ability to sleep normally. The American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders (DSM-IV-TR) classifies sleep disorders as primary (unrelated to any other medical condition or psychological disorder) and secondary (the result of illness, psychological disorders, or the use of drugs or alcohol). Primary sleep disorders are further categorized as either dyssomnias or parasomnias. Dyssomnias affect sleep onset, duration, or quality. The most prevalent dyssomnia is insomnia ; others include narcolepsy , sleep apnea, and circadian rhythm sleep disorders. Parasomnias are abnormal behaviors that occur during sleep. They include nightmares, sleep terrors, and sleepwalking disorders.

Description

Dyssomnias

INSOMNIA

Insomnia is characterized by difficulty falling asleep and staying asleep for an adequate period of time, and/or poor sleep quality. Primary insomnia occurs without an underlying mental condition or illness. Secondary insomnia, the most common form, typically stems from a medical or psychological condition.

SLEEP APNEA

Sleep apnea is a breathing-related sleep disorder. The majority of patients with this disorder have obstructive sleep apnea, which occurs when the upper airway collapses, blocking air flow to the lungs. This can occur up to several hundred times in one night. Each time the airway is blocked, the body’s oxygen level drops, arousing the brain to restart breathing. Individuals with this disorder are not aware that they are waking up, but feel poorly rested during the day.

NARCOLEPSY

Individuals who have narcolepsy fall asleep during inappropriate times during the day, even though they may get adequate sleep at night. People with narcolepsy feel the need to nap frequently, and may experience sudden sleep “attacks.”

CIRCADIAN RHYTHM DISORDERS

The human biological clock is governed by the 24-hour daily light and darkness cycle, which is called the circadian rhythm. Individuals with circadian rhythm disorders are unable to adjust their biological clock to this environmental rhythm, resulting in excessive daytime sleepiness and difficulty falling asleep at the appropriate time.

Parasomnias

Parasomnias are disruptions to the arousal and sleep-stage transitions that involve the autonomic nervous system. They can occur during rapid eye movement (REM) or non-rapid eye movement (NREM) sleep. In primary parasomnias, wakefulness and sleep occur simultaneously. The DSM-IV-TR defines four main types of parasomnias: nightmare disorder, sleep terror disorder, sleepwalking disorder , and parasomnias not otherwise specified.

NIGHTMARE DISORDER

Nightmare disorder is among the sleep disorders that occur during REM sleep, which is when the majority of dreams occur. Individual with this disorder have frightening dreams that they typically remember upon awakening.

SLEEP TERROR DISORDER

Sleep terrors are similar to nightmares in that they involve frightening dreams, but these episodes typically occur during the deep-sleep stages. Affected people are unaware of what is occurring and are unable to communicate.

SLEEPWALKING

Sleepwalking occurs when individuals rise from bed while sleeping and move or walk around. It typically occurs during the period of deep sleep in the early part of the night. Someone who is sleepwalking will not be able to communicate while the episode is occurring, and will not remember the episode the following morning.

Causes and symptoms

Insomnia causes

Primary insomnia is not associated with an underlying psychological or medical problem. Research has suggested that people with primary insomnia may experience a state of hyperarousal that leaves them unable to sleep at night.

Secondary insomnia is associated with conditions that cause discomfort or psychological distress, such as diabetes, heart disease and heart failure, chronic pain , prostate disorders, gastroesophageal reflux disease (GERD), and depression . Insomnia is more prevalent among older adults, who often experience these health conditions, as well as a frequent need to urinate during the night.

A disorder called restless legs syndrome (RLS) often contributes to insomnia. This condition is characterized by a crawling or tingling sensation in the legs, which makes a person feel an uncontrollable urge to move. The leg discomfort typically occurs at night, and makes it difficult for the individual to fall asleep.

Insomnia symptoms

Because people with insomnia do not get adequate sleep each night, they may experience marked daytime sleepiness. People with insomnia often complain of fatigue , a lack of energy, and an inability to concentrate.

Sleep apnea causes and symptoms

Obstructive sleep apnea is caused by the temporary collapse of the airway during sleep. Risk factors include:

  • obesity
  • smoking
  • alcohol and sedative use
  • family history of sleep apnea

During a sleep apnea episode, the breathing becomes shallow or stops periodically. Each time the breathing stops, people affected automatically awaken. Although individuals will not remember these repeated awakenings, they will feel tired and groggy the next day.

People with obstructive sleep apnea experience disturbed sleep, which can lead to daytime sleepiness, irritability, depression, and memory impairment. Untreated sleep apnea has been associated with an increased risk for high blood pressure, heart disease, type 2 diabetes, and mortality.

Narcolepsy causes and symptoms

Narcolepsy occurs due to an abnormality of the central nervous system. It is believed to be caused by a combination of environmental and genetic factors. The majority of people with narcolepsy have a variance in the human leukocyte antigen (HLA) genes (HLA-DR15 and HLA-DQ6), which are involved with immune system function.

The most obvious symptom of narcolepsy is falling asleep at inappropriate times during the day. Other symptoms include cataplexy (sudden muscle weakness that often occurs with an emotional expression such as laughing or anger), hallucinations , sleep paralysis (a feeling of being awake but paralyzed throughout the entire body), and disrupted nighttime sleep.

Circadian rhythm disorder causes and symptoms

The biological clock can get out of step with the circadian rhythm due to travel across different time zones (called jet lag) or late-night shift work. As a result of these circadian rhythm shifts, individuals may experience daytime sleepiness and an inability to fall asleep at appropriate times.

Parasomnias causes and symptoms

Parasomnias occur due to a disassociation between sleep and wakefulness states. Nightmares may be triggered by frightening or stressful events that occur during the day, such as the death of a loved one or the anticipation of a difficult test at school. Individuals with this disorder typically awaken during or after a nightmare and are able to recount the frightening dream.

Sleep terrors may be caused by sleep deprivation or fever. Someone who is experiencing a sleep terror will awaken abruptly, often screaming. The person will be unable to communicate during the experience. Sleep terrors last for about 15 minutes, after which time the person will usually fall back asleep and not remember the episode. In rare cases, individuals experiencing sleep terrors may become violent, causing injury to themselves or others.

Sleepwalking is believed to have a genetic component; it tends to run in families. Other causes may include fever, sleep deprivation, or obstructive sleep apnea. Individuals who sleepwalk will walk or move around while still asleep.

Demographics

Insomnia is the most common sleep disorder, affecting between 30 and 40% of the adult population. About 80% of people with insomnia have the secondary form, meaning that the insomnia occurs as the result of a medical or psychological problem.

Restless legs syndrome (RLS) occurs in about 5% of the population, but the incidence increases with age. Approximately 30% of people over the age of 50 have RLS. Obstructive sleep apnea affects more than 2% of adult women, 4% of adult men, and 3% of children. Narcolepsy is relatively rare, affecting only about 1 out of every 2,000 people. It is more common in men than in women.

Parasomnia events are most common in childhood. As many as 50% of young children experience nightmare disorder. Between one and 17% of children sleepwalk. The occurrence of sleepwalking typically peaks by 12 years of age. Only about 4% of adults sleepwalk.

Diagnosis

The evaluation of any sleep disorder typically begins with a thorough medical history and physical examination. Some patients are asked to keep a sleep diary, in which they chronicle their nightly sleep experiences for two or more weeks. Doctors also may administer sleep questionnaires or psychological screening tests to reveal the nature of the problem.

Sleep studies

To diagnose sleep-related breathing disorders, primarily obstructive sleep apnea, doctors may recommend polysomnography (a sleep study). This study also may be used to diagnose some types of parasom-nias (particularly sleepwalking and sleep terrors). While patients sleep (in a hospital, sleep laboratory, or at home), their blood oxygen level, breathing patterns, heart rate, and brain waves are monitored.

Patients with narcolepsy may visit a sleep laboratory for a multiple sleep latency test (MSLT). In this test, individuals are asked to nap for 20 minutes once every two hours during the course of a day. The lab assesses sleepiness by noting the time it takes them to fall asleep. The shorter the time to sleep, the greater the possibility of a narcolepsy diagnosis .

Treatments

Treatments for insomnia

One of the primary treatments for insomnia and other sleep disorders is sleep hygiene, which involves the following techniques:

  • going to bed at the same time every evening
  • avoiding distracting activities, such as watching television, before bed
  • avoiding exercise within two hours before bedtime
  • using the bed only for sleep (rather than reading or watching TV)
  • limiting caffeine (coffee, tea, chocolate), alcohol, and nicotine within four hours of bedtime
  • avoiding large meals within two hours of bedtime
  • engaging in calming activities, such as taking a warm bath or listening to soothing music

Cognitive behavioral therapy can be useful for some people with insomnia. This psychological technique teaches people to identify the behavioral problems that are contributing to their insomnia, as well as ways to change those behaviors. Part of the treatment approach is to practice good sleep hygiene. Other techniques to help people with insomnia fall asleep include relaxation training (such as self-hypnosis, guided imagery, or paced breathing) and deep muscle relaxation (progressively tensing and then releasing each muscle group to relieve tension).

Medications may also be used to treat insomnia. Several over-the-counter medications are available. Antihistamines, designed to treat colds and allergies, have sedation as a side effect. These drugs can cause grogginess the day after use, because of the rate at which they are eliminated by the body.

The two prescription classes of drugs for treating insomnia are the benzodiazepines and the non-benzo-diazepines. Benzodiazepines include diazepam (Valium) and temazepam (Restoril). These drugs may become addictive and can cause daytime sleepiness. Three newer non-benzodiazepine medications that treat insomnia with less risk of side effects are eszopiclone (Lunesta), ramelteon (Rozerem), and zolpidem (Ambien). Doctors also treat patients with insomnia using medications (for example, antidepressants ) that were designed for other purposes, but which have sedation as a side effect.

A natural substance, melatonin, is sometimes used to treat jet lag and insomnia. Melatonin is a hormone produced by the pineal gland in the brain. It has been called “the hormone of darkness” because levels of melatonin drop when the sun rises. Research suggests that this hormone may be useful for inducing sleep in certain groups of people with insomnia (for example, elderly people with low melatonin levels). However, as of 2007, research has not proven its safety or effectiveness.

If the cause of insomnia is RLS, treatment includes massage, warm baths, and visualization techniques to distract from the discomfort. The only medication approved by the U.S. Food and Drug Administration (FDA) for the treatment of RLS is ropinirole (Requip), although drugs used for the

KEY TERMS

Benzodiazepines —A class of sedative drugs that are used to treat sleep disorders.

Cataplexy —Sudden muscle weakness associated with narcolepsy that is triggered by emotions such as laughter, anger, or fear.

Chronotherapy —A treatment that involves sleeping at predetermined times in order to reset the circadian rhythm.

Circadian rhythm —The light-dark cycle in the body that occurs over a period of approximately 24 hours.

Cognitive behavioral therapy —A type of therapy that helps patients identify and change problematic thoughts and behaviors.

Continuous positive airway pressure (CPAP) —A treatment for obstructive sleep apnea that uses a mask to deliver oxygen into the airway while the patient sleeps.

Dyssomnias —Sleep disorders that affect the onset, duration, and quality of sleep.

Insomnia —A sleep disorder marked by the inability to fall asleep or remain asleep for an adequate period of time.

Melatonin —A hormone produced by the pineal gland that is associated with sleep, and that may be useful in the treatment of some sleep disorders.

Narcolepsy —A sleep disorder that causes the sudden, uncontrollable urge to sleep.

Obstructive sleep apnea —A complete or partial blockage of the airway that results in repeated awakenings during the night.

Parasomnias —Abnormal behaviors or other disruptive events that occur during sleep.

Phototherapy —A treatment that exposes the patient to bright light at specific times during the sleep-wake cycle to readjust the circadian rhythm.

Polysomnography —A sleep study that assesses oxygen flow, brain waves, and other measurements to diagnose sleep disorders.

Sleep paralysis —A symptom of narcolepsy in which the individual feels awake but unable to move.

Rapid eye movement (REM) sleep —The stage of sleep that is associated with rapid eye movements and dreaming.

Restless legs syndrome —A tingling, creeping sensation in the legs that produces an uncontrollable urge to move.

treatment of Parkinson’s disease, benzodiazepines, and anticonvulsant medications also may be effective.

Treatments for sleep apnea

Treatments for obstructive sleep apnea include weight loss if the individuals are overweight. People with this condition should avoid alcohol, sedatives , and smoking. The primary treatment is continuous positive airway pressure (CPAP), a mask that delivers oxygen into the airway while affected people sleep. If these treatments are ineffective, surgery may be needed to increase the size of the airway; however, surgery is only effective in approximately 50% of patients.

Treatments for narcolepsy

Narcolepsy treatment primarily involves behavioral therapies, such as scheduling 15–20-minute daytime naps every four hours, and maintaining a regular sleep-wake cycle. Amphetamines and the stimulant modafinil (Provigil) can be used to treat excessive daytime sleepiness. To treat cataplexy, doctors may prescribe the antidepressants clomipramine (Anafranil) or fluoxetine (Prozac).

Treatments for circadian rhythm disorder

Two primary types of treatments exist for circadian rhythm disorders: chronotherapy and phototherapy. In chronotherapy, patients delay or hasten sleep, and sleep for a predetermined number of hours to get the body back on the appropriate sleep schedule. Phototherapy exposes patients to bright light at specific times during the sleep-wake cycle to readjust the circadian rhythm.

Treatments for parasomnias

If patients have episodes that are frequent and particularly disturbing, consultation with a psychologist or psychiatrist can be helpful for identifying underlying causes. When sleepwalking occurs, it is helpful to secure the area by removing clutter on the

floor and locking the doors and windows to prevent the individual from injury.

Prognosis

About 85% of people with insomnia find relief with a combination of sleep hygiene and medication. Although there is no cure for sleep apnea, treatment can reduce the associated risks of high blood pressure and heart disease. No current treatment method can completely alleviate narcolepsy, but cataplexy can be successfully controlled with medication, and many people find that their symptoms naturally decrease after age 60. Parasomnias generally diminish as children grow into adulthood.

Prevention

Certain sleep disorders, such as insomnia, can sometimes be prevented by practicing good sleep hygiene. As mentioned, sleep hygiene involves going to bed at a regular time each night and avoiding stimulating activities close to bedtime. Sleep apnea may be prevented in some cases by controlling body weight.

Resources

BOOKS

American Academy of Sleep Medicine. International Classification of Sleep Disorders: Diagnostic & Coding Manual. 2nd ed. Westchester, IL: American Academy of Sleep Medicine, 2005.

Kryger, Meir. A Woman’s Guide to Sleep Disorders. New York: McGraw Hill Books, 2004.

Perlis, Michael L., and Kenneth L. Lichstein, eds. Treating Sleep Disorders: Principles and Practice of Behavioral Sleep Medicine. Hoboken, NJ: Wiley, 2003.

Radulovacki, Miodrag, ed. Sleep-Related Breathing Disorders. New York: Marcel Dekker, 2003.

ORGANIZATIONS

American Academy of Sleep Disorders. One Westbrook Corporate Center, Suite 920, Westchester, IL 60154. (708) 492-0930. http://www.aasmnet.org/

National Centers on Sleep Disorders Research, National Institutes of Health. 6701 Rockledge Drive, MSC 7920, Bethesda, MD 20892. (301) 435-0199. http://www.nhlbi.nih.gov/about/ncsdr/index.htm

National Institute of Neurological Disorders and Stroke. P.O. Box 5801, Bethesda, MD 20824. (800) 352-9424. http://www.ninds.nih.gov/index.htm

National Sleep Foundation. 1522 K Street, NW Suite 500, Washington DC 20005. (202) 347-3471. http://www.sleepfoundation.org/joinus/index.php

Stephanie N. Watson
Ruth A. Wienclaw, PhD

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Sleep Disorders

Sleep Disorders

Insomnias and hypersomnias

Observation and classification of sleep disorders

Dyssomnias

Parasomnias

Diagnosis of sleep disorders

The sleeping brainthe new frontier

Resources

Sleep disorders are chronic sleep irregularities, which drastically interfere with normal nighttime sleep or daytime functioning. There are about 70 different sleep disorders. Sleep-related problems are the most common complaint heard by doctors and psychiatrists, the two most common being insomnia (inability to go to sleep or stay asleep), and hyper-somnia (excessive daytime sleepiness). While most people experience both problems at some time, it is only when they cause serious intrusions into daily living that they warrant investigation as disorders.

Although sleep is a basic behavior in animals as well as humans, researchers still do not completely understand it. In the past 60 years, however, researchers have learned about the pattern of different types of sleep and its effects on breathing, heart rate, brain waves, and so on. Sleep disorders research, as a relatively new field of medicine, was stimulated by the discovery in 1953 of REM (rapid eye movement) sleep and the more recent discovery in the 1980s that certain irregular breathing patterns during sleep can cause serious illness and sometimes death. While medical knowledge of sleep disorders is expanding rapidly, clinical educational programs still barely touch on the subject, about which many physicians, psychiatrists and neurologists remain seriously undereducated.

Insomnias and hypersomnias

Insomnias include problems with sleep onset (taking longer than 30 minutes falling asleep), sleep maintenance (waking five or more times during the night or for a total of 30 minutes or more), early arousal (less than 6.5 hours of sleep over a typical night), light sleep, and conditioning (learning not to sleep by associating certain bedtime cues with the inability to sleep). Insomnias may be transient (lasting no longer than three weeks) or persistent. Most people experience transient insomnias, perhaps due to stress, excitement, illness, or even a sudden change to high altitude. These are treatable by short-term prescription drugs and, sometimes, relaxation techniques. When insomnia becomes persistent, it is usually classed as a disorder. Persistent insomnias may result from medical and/or psychiatric disorders, prescription drug use, and substance abuse, and often result in chronic fatigue, impaired daytime functioning, and hypersomnia.

Hypersomnias manifest as excessive daytime sleepiness, uncontrollable sleep attacks, and, in the extreme, causes people to fall asleep at highly inappropriate times, such as driving a car or when holding a conversation. Most hypersomnias, like narcolepsy and those associated with apnea (breathing cessation), are caused by some other disorder and are therefore symptomatic. Some, however, like idiopathic central nervous system (CNS) hypersomnia and Kleine-Levin syndrome, are termed idiopathic for their unknown origin. CNS hypersomnia causes a continuous state of sleepiness from which long naps and nighttime sleep provides no relief. This is usually a life-long disorder and treatment is still somewhat experimental and relatively ineffective. Kleine-Levin syndrome is a rare disorder seen three times as often in males as females, beginning in the late teens or twenties. Symptoms are periods of excessive sleepiness, excessive overeating, abnormal behavior, irritability, loss of sexual inhibition, and sometimes hallucinations. These periods may last days or weeks, occur one or more times a year, and disappear about the age of 40 years. Behavior between attacks is normal, and the sufferer often has little recall of the attack. Stimulant drugs may reduce sleepiness for brief periods, and lithium meets with some success in preventing recurrence.

Observation and classification of sleep disorders

Sleep abnormalities intrigued even the earliest medical writers who detailed difficulties that people experienced with falling asleep, staying asleep, or staying awake during the day. By 1885, Henry Lyman, a professor of neurology in Chicago, Illinois, classified insomnias into two groups: those resulting from either abnormal internal or physical functions; or from external, environmental influences. In 1912, Sir James Sawyer reclassified the causes as either medical; or psychic, toxic, or senile. Insomnias were divided into three categories in 1927: inability to fall asleep, recurrent waking episodes, and waking earlier in the morning than appropriate. Another reclassification, also into three categories, was made in 1930: insomnia/hypersomnia, unusual sleep-wake patterns, and parasomnias (interruption of sleep by abnormal physical occurrences). One change to that grouping was made in 1930 when hypersomnias and insomnias became separate categories.

Intense escalation of sleep study in the 1970s saw medical centers begin establishing sleep disorder clinics where researchers increasingly uncovered abnormalities in sleep patterns and events. It was during this decade that sleep disorders became an independent field of medical research and the increasing number of sleep disorders being identified necessitated formal classification.

Dyssomnias

This group includes both insomnias and hyper-somnias, and is divided into three categories: intrinsic, extrinsic, and circadian rhythm sleep disorders. Intrinsic sleep disorders originate within the body and include narcolepsy, sleep apnea, and periodic limb movements.

Narcolepsy is associated with REM sleep and the central nervous system. It causes frequent sleep disturbances and thus excessive daytime drowsiness. Subjects may fall asleep without warning, experience cataplexymuscle weakness associated with sudden emotional responses like anger, which may cause collapseand temporarily be unable to move immediately before falling asleep or just after waking up. While narcolepsy is manageable clinically and brief naps of 10 to 20 minutes may be somewhat refreshing, there is no cure.

Apnea is the brief cessation of breathing. obstructive sleep apnea is caused by the collapse of the upper airway passages that prevent air intake, while central apnea occurs when the diaphragm and chest muscles cease functioning momentarily. Both apneas result in a suffocating sensation, which goes unnoticed but causes enough arousal to enable breathing to begin again. Bed partners report excessive snoring and repeated brief pauses in breathing. Apneas may disrupt sleep as many as several hundred times a night, naturally resulting in excessive daytime sleepiness. Severe episodes can actually cause death, usually from heart failure. Treatment for obstructive apnea includes pumping air through a nasal mask to keep air passages open, while some success in treating central apnea can be obtained with drugs and mechanical breathing aids.

Periodic limb movement (PLM) and restless leg syndrome (RLS) result in sleep disruptions and therefore hypersomnia. PLM occurs during sleep and subjects experience involuntary leg jerks (sometimes arms also). The subject is unaware of these movements but bed partners complain of being kicked and hit. In RLS, crawling or prickling sensations seriously interfere with sleep onset. Although their causes are yet unknown, certain drugs, stretching, exercise, and avoiding stress and excessive tiredness seem to provide some relief.

Extrinsic sleep disorders are caused by external influences such as drugs and alcohol, poor sleep hygiene, high altitude, and lack of regular sleep limit-setting for children.

Drug- and alcohol-related sleep disorders result from stimulant, sedative, and alcohol use, all of which can affect, and severely disrupt, the sleep-wake schedule. Stimulants, including amphetamines, caffeine, and some weight loss agents, can cause sleep disturbances and may eventually result in the need for excessively long periods of sleep. Prolonged use of sedatives, including sleeping pills, often result in severe rebound insomnia and daytime sleepiness. Sudden withdrawal also produces these effects. Alcohol, while increasing total sleep time, also increases arousal, snoring, and the incidence and severity of sleep apnea. Prolonged abuse severely reduces REM and delta (slow-wave) sleep, and sudden withdrawal results in severe sleep-onset difficulties, significantly reduced delta sleep, and REM rebound, causing intense nightmares and anxiety dreams for prolonged periods.

Circadian rhythm sleep disorders either affect or are affected by circadian rhythms, which determine humans approximate 25-hour biological sleep-wake pattern and other biological functions. Disorders may be transient or permanent.

Jet-lag and shift work-related circadian rhythm disorders are transient. Because the human biological clock runs slightly slower than the 24-hour solar clock, it must adjust to external time cues like alarm clocks and school or work schedules. Circadian rhythms must therefore phase-advance to fit the imposed 24-hour day. The body has difficulty phase-advancing more than one hour each day, therefore people undergoing drastic time changes after long-distance air travel suffer from jet lag. Hypersomnia, insomnia, and a decrease in alertness and performance are not uncommon and may last up to ten days, particularly after eastward trips longer than six hours. Night-shift workers, whether permanent or alternating between day and night shifts, experience similar symptoms, which may become chronic because circadian rhythms induce maximum sleepiness during the sun-clocks night and alertness during the sun-clocks day, regardless of how long a person works nights.

Delayed sleep phase syndrome is a chronic condition in which waking to meet normal daily schedules is extremely difficult. Such people are often referred to as night people because they feel alert late in the day and at night while experiencing fatigue and sleepiness in the mornings and early afternoons. This is because their biological morning is the middle of the actual night. Phase-delaying the sleep-wake schedule by going to bed three hours later and sleeping three hours longer until the required morning arousal time is reached, can often synchronize the two. Exposure to artificial, high-intensity, full spectrum light from about 7 to 9 A.M. often proves helpful.

Advanced sleep phase syndrome is much less prevalent and shows the reverse pathology to phase-delayed syndrome. Phase-advancing the sleep-wake schedule and light therapy during evening hours may prove helpful.

Parasomnias

Parasomnias are events caused by physical intrusions into sleep that are thought to be triggered by the central nervous system. These dysfunctions do not interfere with actual sleep processes and do not cause insomnia or hypersomnia. They appear more frequently in children than adults.

Arousal disorders appear to be associated with neurological arousal mechanisms. They usually occur early in the night during slow-wave rather than REM sleep and are therefore not the acting out of a dream.

Sleepwalking occurs during sleep. The subject may seem wide awake but displays a blank expression, seldom responds when spoken to, is difficult to awaken, moves clumsily, and sometimes bumps into objects, although they will often maneuver effectively around them. Some sleepwalkers perform dangerous activities, like driving a car. Although rarely in the case with children, serious injuries can occur. Subjects displaying dangerous tendencies should take precautions like locking windows and doors. Episodes average about ten minutes, seldom occur more than once in any given night, and are seldom remembered.

Night or sleep terrors are sudden partial awakenings during non-REM sleep. Traditionally, a sufferer sits bolt upright in bed in a state of extreme panic, screams loudly, sweats heavily, and displays a rapid heart beat and dilated pupils. The patient will sometimes talk, and might even flee from bed in terror, often running into objects and causing injury. Episodes last about 15 minutes, after which sleep returns easily. There is seldom any recollection of the event. If woken, the subject may display violence and confusion and should, instead, be gently guided back to bed.

Rapid eye movement (REM) sleep parasomnias take place during sleep and include nightmares and the recently discovered REM sleep behavior disorder. This potentially injurious disorder is seen mostly in elderly men and results in aggressive behavior while sound asleep such as punching, kicking, fighting, and leaping from bed in an attempt to act out a dream.

Subjects report their dreams, usually of being attacked or chased, become more violent and vivid over the years. Some sufferers even tie themselves into bed to avoid injury. Unfortunately, this disorder was seriously misdiagnosed until recently. It is now readily diagnosable and easily treated.

Sleep-wake transition disorders usually occur during transition from one sleep stage to another, or while falling asleep or waking up. Manifestations include sleeptalking, leg cramps, headbanging, hypnic jerks (sleep starts), and teeth-grinding.

Other parasomnias include excessive snoring, abnormal swallowing, bedwetting, sleep paralysis, and for some individuals, sudden unexplained death during sleep.

Diagnosis of sleep disorders

Identifying each specific sleep disorder is imperative for effective treatment, as treatment for one may adversely effect another. While sleeping pills may help in some instances, in others they exacerbate the problem. The most important step in diagnosis is the sleep history, a highly detailed diary of symptoms and sleep-wake patterns. The patient records events such as daily schedule; family history of sleep complaints; prescription or non-prescription drug use; and symptoms when they occur, how long they last, their intensity, whether they are seasonal, what improves or worsens them, and effects of stress, family or environmental factors. Important contributors are family members or friends; for example, a bed partner or parent may be the only observer of unusual occurrences during the patients sleep.

The sleeping brainthe new frontier

Many undiscovered secrets lie hidden behind the doors of sleep and its related disorders. However, the future looks bright for sufferers of sleep disorders. Intense interest from researchers, satisfaction of an increasing number of accurately diagnosed and treated patients, advances in technology, and the formation of a National Institute of Health Commission on Sleep by the U.S. Congress, suggest that research, training, education, and recognition in this area of medicine will continue to flourish.

Resources

BOOKS

Billiard, Michel, ed. (translated by Angela Kent). Sleep: Physiology, Investigations, and Medicine. New York: Kluwer Academic/Plenum, 2003.

Horne, James A. Sleepfaring: A Journey Through the Science of Sleep. Oxford, UK: Oxford University Press, 2006.

KEY TERMS

Apnea Cessation of breathing.

Delta sleep Slow-wave, stage 4 sleep that normally occurs before the onset of REM sleep.

Extrinsic Caused by something on the outside.

Hypersomnia Excessive daytime sleepiness.

Idiopathic Disease of unknown origin.

Insomnia Inability to go to sleep or stay asleep.

Intrinsic Not dependent on external circumstances.

Parasomnia Interruption of sleep by abnormal physical occurrences.

Polysomnography Electronic monitoring equipment measuring brain waves, eye and muscle movement, heart rate, and other physiological functions.

REM sleep Rapid eye movement sleep that is characterized by dreaming, active brain activity, and numerous eye movements.

Lader, Malcolm, Daniel P. Cardinali, and S.R. Pandi-Perumal, eds. Sleep and Sleep Disorders: A Neuropsychopharmacological Approach. New York: Springer, 2005.

Lee-Chiong, Teofilo L. Sleep: A Comprehensive Handbook. Hoboken, NJ: Wiley-Liss, 2006.

Mattson, Mark P., ed. Sleep and Aging. Amsterdam, Netherlands: Elsevier, 2005.

Mindell, Jodi A. A Clinical Guide to Pediatric Sleep: Diagnosis and Management of Sleep Problems. Philadelphia, PA: Lippincott Williams & Wilkins, 2003.

Moorcroft, William H. Understanding Sleep and Dreaming. New York: Springer, 2005.

Rosen, Marvin. Sleep and Dreaming. Philadelphia, PA: Chelsea House Publishers, 2005.

Steriade, Mircea. Brain Control of Wakefulness and Sleep. New York: Springer, 2005.

Marie L. Thompson

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Sleep Disorders

Sleep disorders

Definition

Sleep disorders involve a variety of persistent problems that people have with falling asleep, staying asleep, and quality of sleep. They may also involve sleeping too little or too much.

Description

Lack of proper sleep can interfere with memory and learning, compromise the body's immune system , play havoc with people's emotional states, and shorten the life span. Inadequate sleep can also increase pain in arthritis sufferers and complicate diabetes, as well as increase the risk of diabetes and heart disease . Since sleep helps regulate body functions, including hormone production, lack of sleep increases the risk of developing diabetes and is worse if you sleep five hours or less each night.

A 17-year study reported at the British Sleep Society in 2008 revealed that people who had five or fewer hours sleep each night also had increased their risk of dying from any cause. These people also doubled their risk of dying from heart disease because lack of sleep elevated blood pressure . The study also found that sleeping more than eight hours also increased mortality risk, but not from heart disease.

Further, lack of sleep in the workplace costs employers $50 billion in lost productivity and accounts for $15 billion in medical expenses yearly. Many companies report increased end-of-shift injuries due to lack of sleep.

A study published in 2007 linked sleep deprivation with heightened emotions and impulsive behaviors. Sleep was found to be necessary to restore rational emotional brain pathways.

Types of sleep disorders

Many adults report sleep problems of varying kinds. The International Classification of Sleep Disorders, Second Edition lists 81 different sleep disorders. There are ten primary disorders that are common and fall into six areas: insomnia , breathing related disorders, movement disorders, circadian rhythm sleep disorders, inadequate sleep hygiene, and parasomnias (sleep disorders marked by night terrors or sleep-walking).

Older adults may experience any of these sleep disorders, however, they also have special needs. They generally require as much sleep as they once did, between 7 and 9 hours every night, but now get sleepy earlier in the evening and get up earlier. They also have trouble falling asleep, staying asleep, and getting back to sleep. This may be due to a sleep-wake cycle that does not work as well as it did or to sleep habits, diseases, or medications. Older adults also may secrete less melatonin, a hormone that promotes sleep.

In addition, sleep disorders may underlie sleep problems in menopausal women. Though these women often report having their sleep interrupted by hot flashes, a 2008 study revealed that sleep disorders may also be occurring. Treating hot flashes, the study emphasized, would not help women sleep better. Doctors need to look at other factors when women report interrupted sleep and feel it is because of hot flashes.

Unfortunately, sleep disorders in older adults are underdiagnosed and undertreated. In 2007, The National Coalition for Sleep Disorders in Older People was formed to develop comprehensive guidelines for diagnosis and treatment of sleep disorders in older Americans. The coalition consists of twelve organizations, including the American Association of Retired Persons (AARP ), AGS Foundation for Healthy Aging, and the National Sleep Foundation.

INSOMNIA Most sleep disturbances can be lumped under insomnia. This is a broad definition of conditions that interfere with satisfying sleep. Some of these conditions are caused by poor sleep hygiene; others are due to other factors.

Older men have more trouble with sleep, taking longer to fall asleep and waking up more often than older women. Both men and women experience lighter and less restful sleep and have fewer episodes of deep REM (rapid eye movement) sleep where dreams originate.

Insomnia can be temporary. Situational insomnia is the result of stressful life events such as worry over finances, concerns about an ill relative, or a death in the family. Sleeplessness or interrupted sleep may last three weeks or less. Normal sleep usually returns when the stress is passed or resolved. Some doctors may recommend medications or counseling to help the patient through this stressful time.

Chronic insomnia lasts more than three weeks. It must be treated by dealing with the underlying problem. Sometimes this insomnia is the result of anxiety disorders, illness, or chronic stress.

BREATHING RELATED DISORDERS Sleep apnea is the most common breathing related sleep disorder. It is a condition marked by loud snoring interspersed with episodes where a person stops breathing for 10 to 30 seconds during sleep. When the person starts breathing again, the breath is taken as a loud gasp that often wakes the sleeper. Sometimes, the person comes fully awake and wonders what woke him or her up. At other times, the sleeper comes to light wakefulness. In either case, the sleeper does not sleep deeply. Sleep apnea can cause daytime tiredness or drowsiness and can contribute to heart disease because sleep apnea episodes raise blood pressure. A 2005 study showed strong evidence that sleep apnea also caused strokes.

MOVEMENT DISORDERS There are two movement disorders involving poor sleep: restless leg syndrome and periodic limb movement disorder . These disorders appear more frequently in older adults than in younger people. Restless leg syndrome is a crawling feeling in the legs that makes the sleeper uncomfortable and want to move the legs. This often keeps the sleeper awake at night. Older adults are more likely to have restless leg syndrome.

People with periodic limb movement disorder kick every 20 to 40 seconds in their sleep, often forcing their bed partners to sleep elsewhere. Some people have both restless leg syndrome and this condition as well.

CIRCADIAN RHYTHM SLEEP DISORDERS These sleep disorders can be temporary. They often deal with circumstances that upset the normal sleep-wake pattern within a 24-hour cycle. Jet lag caused by traveling quickly from one part of the country or world to another can move bedtimes farther from the body's normal bedtime or closer to it.

Though many older people may be retired, some may volunteer or work part-time. If they volunteer at a crisis line or work at a convenience store or all-night retail store, they may work at night for a few days and then have several days off. People who do this often have trouble adjusting to different patterns of sleeping and waking.

PARASOMNIAS These sleep disorders are marked by night terrors or sleepwalking. Though they are most common in childhood, they can still occur in the elderly. Sometimes, vivid nightmares are due to strange surroundings, traumatic stress, or medications. Sleepwalking can also be the result of medications, food allergies, or an inherited condition, but usually has occurred previously in the patient's life.

Demographics

The National Sleep Foundation reports that 75 percent of adults in the US have trouble sleeping at least a few nights each week. Nearly half of older adult between the ages of 65 and 79 report mild to severe sleep problems.

Causes and symptoms

Causes

Many conditions can cause sleep disorders. Simple insomnia can be caused by stress or worry, depression , anxiety, using caffeine or other stimulants, using alcohol or sedatives, poor sleep habits, seasonal factors, pain, or urinary frequency or incontinence. Being overweight can cause breathing problems that disturb sleep.

Some medications, especially diuretics that cause frequent urination, if taken near bedtime, can interrupt sleep by having the patient get up to go to the bathroom. Taking multiple medications can lead to feeling tired all the time and can sometimes interfere with sleep.

Chronic illnesses such as diabetes can cause pain or restlessness that interrupts sleep. Arthritis pain and stiffness can make falling to sleep difficult. Some Alzheimer's patients sleep less and wake up more often and others sleep too much.

Symptoms

The symptoms of sleep disorders can vary, depending on the condition causing poor sleep. In general, most patients report having trouble getting to sleep. They may wake up often during the night or wake up and not be able to go back to sleep. They also do not feel rested when they wake and may feel tired during the day. Moreover, they may feel anxious around bedtime because of past experience with poor sleep.

Patients with sleep apnea often snore loudly and are startled awake as they gasp for their next breath. Often, bed partners report these episodes clearly though the patient may not be aware of them. Bed partners also report periodic limb movement disorder or restless leg syndrome because their own sleep is disturbed by the movements of their partners. Many restless leg syndrome patients, however, do report feeling crawly or itchy sensations in leg muscles throughout the night.

Diagnosis

The doctor will review the patient's medical history and will ask about the patient's sleep patterns and sleep habits. The patient's bed partner may need to accompany the patient to explain what he or she has observed during the patient's sleep and how that has affected him or her. The doctor will do a physical exam.

Usually, treatment recommendations begin at this stage. However, some doctors may want more details, especially if sleep apnea or movement disorders are suspected. The doctor then may send the patient to a sleep specialist at a sleep center. There, the patient may undergo a polysomnogram, an overnight sleep study. This test measures heart rate, breathing, body movements, and brain waves. The specialist may conduct a multiple sleep latency test instead. This test has the patient nap every two hours in the daytime. If the patient falls asleep quickly, that means the patient is not getting adequate sleep at night.

Treatment

The first line of treatment is usually instilling good sleep hygiene. That means going to bed and rising at the same time every day, trying not to take naps longer than twenty minutes during the day, avoiding caffeinated drinks after lunch, and not drinking alcohol in the evening. Doctors usually recommend having the patient exercise during the day, but not within three hours of bedtime. If the person cannot fall asleep within thirty minutes of going to bed, the person should get up and go into another room to do something quite, such as reading or listening to soft music. Then, the person can return to bed and try to fall asleep.

The bedroom should be used only for sleep and romance, not for watching television or reading. The rooms should be kept dark and cool. Soft music may be played to encourage a relaxing mood. Sometimes, a massage or a warm bath before bed helps. Many doctors encourage people who have insomnia to create a bedroom routine, doing the same relaxing things every night about a half hour to an hour before bed, cueing the body and the mind for sleep.

If there are medical conditions that are keeping the person awake, the doctor should make sure that these conditions are under adequate control. The doctor may be able to prescribe pain medications or alter the time of day in which medications are taken in order to ensure uninterrupted sleep.

Doctors may also recommend relaxation techniques or counseling to deal with anxiety disorders or stress issues. Physical exercise or movement therapy such as Tai Chi , Yoga , or dance can also help older adults sleep better.

Patients with sleep apnea often wear a nasal mask attached to a machine that provides continuous airway pressure to keep the nasal passages open. This prevents snoring and allows the person to have a deeper sleep experience. Sometimes mouth guards are used instead to keep the airway open.

Restless leg syndrome can sometimes be managed by placing hot or cold packs on the legs or taking a hot or cold bath. Some people massage the legs before bed. Others use relaxation techniques. Exercise during the day may also help. There are medications for this condition as well as periodic limb movement disorder. However, some of these drugs also produce sleepwalking or eating in one's sleep or even addictive behaviors such as gambling.

WHEN TO SEE THE DOCTOR

  • If a person cannot sleep well every night for two weeks, an appointment should be made to see a doctor.

Medications

New, safer, more effective drugs have replaced the habit-forming sedatives and barbiturates of the past. Benzodiazepines (estazolam, oxazepam, and temazepam) are older drugs that are still used, especially to treat night terrors or sleepwalking. They are habit-forming. Imidazopyrines (eszapiclone, zaleplon, and zolpidem) work like benzodiazepines but leave the body quickly. They are not likely to be habit-forming or cause daytime drowsiness. They can, however, produce bizarre behaviors. Melatonin receptor agonist (ramelteon) works like the hormone melatonin. It is fast-acting and is flushed from the body quickly. It does not appear to be habit-forming.

Alternative treatments

The most popular supplements used as sleep aids are melatonin and valerian. Melatonin is produced by the pineal gland in the brain. When taken in low doses, it seems to have favorable results when used for temporary relief from jet lag. Valerian, an herb, however, has little research backing its effectiveness.

Bach Flower Remedies Rescue Sleep is another herbal alternative. It is a mixture of six flower essences that are sprayed under the tongue. The aroma and taste are found to be relaxing and therefore sleep inducing.

Nutrition/Dietetic concerns

Caffeine consumption can lead to wakefulness and trouble falling asleep. Many doctors recommend that no coffee, black tea, or sodas with caffeine should be consumed at night or even in the afternoon.

Therapy

Behavioral therapy and cognitive therapy may be helpful to some patients with sleep disorders. Behavioral therapists help patients learn relaxation training, deep breathing, and progressive muscular relaxation. They may even offer ways for patients to meditate. A relaxed state in body and mind is helpful for drifting off to sleep.

KEY TERMS

Circadian rhythm —A body rhythm within a 24 hour cycle

Jet lag —Disruption of the sleep-wake cycle due to travel across several time zones within one day.

Melatonin —A hormone that promotes sleep.

Polysomnogram —An overnight sleep study.

REM sleep —Rapid eye movement sleep phase where dreaming occurs.

Sleep apnea —Repeated episodes of temporary suspension of breathing during sleep.

Sleep center —A clinic where doctors diagnose, treat, and do research on sleep disorders.

Some behavioral therapists help patients create relaxing environments in the bedroom. They insist that the bedroom be only used for sex and sleep. Stimulus control therapy also has the patient maintain a consistent bedtime and rising time.

Sleep restriction therapy sets a bedtime later that than normal, making sure the patient gets at least five hours sleep. But the patient gets up at the same time each morning. This is done for a week, then the bedtime is moved up 15 minutes earlier each week until the patient can sleep for 7 to 9 hours each night.

Cognitive therapy helps patients reframe their negative sleep experiences. It replaces negative statements about sleep with positive ones.

Prognosis

The prognosis for treatment of most sleep disorders in the elderly depends on the nature of the disorder. Some sleep problems are temporary and resolve with time or little intervention. Some can be corrected with healthy sleep hygiene. Others may be the result of medical conditions that may or may not have a solution that will encourage satisfying sleep. In most cases, therapy, medications, and good sleep habits offer hope to many sleep-deprived older adults.

Prevention

Generally, good sleep habits can prevent many sleep problems. However, for some patients some sleep disorders cannot be prevented but can be managed.

Caregiver concerns

Patients with sleep apnea should be carefully screened for heart disease and stroke risk factors and monitored closely. In addition, menopausal patients should also be screened for sleep disorders when they present with interrupted sleep they think is due to hot flashes.

Resources

PERIODICALS

Contie, Vicki. “Lack of sleep disrupts brain's emotional controls.” Research Matters, National Institutes of Health. (November 5, 2007): NA

Cooper, Phyllis G. “Insomnia (Adult Health Advisor 2007).” Clinical Reference Systems. (May 31, 2007): NA

“Help for Insomnia.” Harvard Health Commentaries. (April 23, 2007): NA

“Insomnia in older adults (Senior Health Advisor 2007).” Clinical Reference Systems. (May 31, 2007): NA

Kiefer, Dale. “Lack of sleep increases mortality risk.” Life Extension. (January 2008): NA

“New coalition to tackle sleep disorders in older adults.” Medical Condition News. (August 16, 2007): NA

“Nighttime awakenings in menopause may be caused by sleep disorders, not hot flashes.” Harvard Women's Health Watch. (February 2008): NA

Pallarito, Karen. “Sleep problems plague the older set.” HealthDay. (November 23, 2007): NA

“Women and sleep: Not always the best of friends.” Harvard Health Commentaries. (August 21, 2006): NA

Author. “article title.” Journal Name. (date):page

OTHER

NIH Senior Health www.nihseniorhealth.gov

Sleep Education http://www.sleepeducation.com

ORGANIZATIONS

American Insomnia Association (AIA), One Westbrook Corporate Center, Suite 920., Westchester, IL, 60154, 708-492-0939, www.americaninsomniaassociation.org.

American Sleep Apnea Association (ASAA), 1424 K Street, NW, Suite 302., Washington, DC, 20005, 202-293-3650, www.sleepapnea.org.

Better Sleep Council, 501 Wythe Street., Alexandria, VA, 22314, 703-683-8371, www.bettersleep.org.

National Institute on Aging (NIA), 31 Center Drive, MSC 2292, Building 31, Room 5C27, Bethesda, Maryland, 20892, 301-496-1752, 301-496-1072, www.nia.nih.gov.

National Institute on Neurological Disorders and Stroke (NINDS), P.O. Box 5801., Bethesda, MD, 20824, 800-468-9424, www.ninds.nih.gov.

National Sleep Foundation, 1522 K Street, NW, Suite 500., Washington, DC,, 202-347-3471, www.sleepfoundation.org.

Restless Legs Syndrome Foundation, 819 Second Street, SW., Rochester, MN, 55902, 507-287-6465, www.rls.org.

Janie F. Franz

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Sleep Disorders

Sleep disorders

Definition

Sleep disorders are a group of syndromes characterized by disturbance in a person's amount of sleep, quality or timing of sleep, or in behaviors or physiological conditions associated with sleep. There are about 70 different sleep disorders. To qualify for the diagnosis of sleep disorder, the condition must be a persistent problem, cause an individual significant emotional distress, and interfere with social or occupational functioning. The text revision of the fourth edition (2000) of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV-TR) specifically excludes temporary disruptions of sleeping patterns caused by travel or other short-term stresses.

Although sleep is a basic behavior in animals as well as humans, researchers still do not completely understand all of its functions in maintaining health. In the past 30 years, however, laboratory studies on human volunteers have yielded new information about the different types of sleep. Researchers have learned about the cyclical patterns of different types of sleep and their relationships to breathing, heart rate, brain waves, and other physical functions. These measurements are obtained by a technique called polysomnography .

There are five stages of human sleep. Four stages have non-rapid eye movement (NREM) sleep, with unique brain wave patterns and physical changes occurring. Dreaming occurs in the fifth stage, during rapid eye movement (REM) sleep.

  • Stage 1 NREM sleep. This stage occurs while a person is falling asleep. It represents about 5% of a normal adult's sleep time.
  • Stage 2 NREM sleep. In this stage, (the beginning of "true" sleep), the person's electroencephalogram (EEG) will show distinctive wave forms called sleep spindles and K complexes. About 50% of sleep time is stage 2 NREM sleep.
  • Stages 3 and 4 NREM sleep. Also called delta or slow wave sleep, these are the deepest levels of human sleep and represent 10-20% of sleep time. They usually occur during the first 30-50% of the sleeping period.
  • REM sleep. REM sleep accounts for 20-25% of total sleep time. It usually begins about 90 minutes after a person falls asleep, an important measure called REM latency. It alternates with NREM sleep about every hour and a half throughout the night. REM periods increase in length over the course of the night.

Sleep cycles vary with a person's age. Children and adolescents have longer periods of stage 3 and stage 4 NREM sleep than do middle aged or elderly adults. Because of this difference, a doctor will need to take a person's age into account when evaluating a sleep disorder. Total REM sleep also declines with age.

The average length of nighttime sleep varies among people. Most individuals sleep between seven and nine hours a night. This population average appears to be constant throughout the world. In temperate climates, however, people often notice that sleep time varies with the seasons. It is not unusual for people in North America and Europe to sleep about 40 minutes longer per night during the winter.

Description

The DSM-IV-TR classifies sleep disorders based on their causes. Primary sleep disorders are distinguished from those that are not caused by other mental disorders, prescription medications, substance abuse, or medical conditions. The two major categories of primary sleep disorders are the dyssomnias and the parasomnias.

Dyssomnias

Dyssomnias are primary sleep disorders in which a person suffers from changes in the amount, restfulness, and timing of sleep. The most important dyssomnia is primary insomnia, which is defined as difficulty in falling asleep or remaining asleep that lasts for at least one month. It is estimated that 35% of adults in the United States experience insomnia during any given year, but the number of these adults who are experiencing true primary insomnia is unknown. Primary insomnia can be caused by a traumatic event related to sleep or bedtime, and it is often associated with increased physical or psychological arousal at night. People who experience primary insomnia are often anxious about not being able to sleep. Individuals may then associate all sleep-related things (their bed, bedtime, etc.) with frustration, making the problem worse. They then become more stressed about not sleeping. Primary insomnia often begins in young adulthood or in middle age.

Hypersomnia is a condition marked by excessive sleepiness during normal waking hours. Affected persons either have lengthy episodes of daytime sleep or episodes of daytime sleep on a daily basis even though they are sleeping normally at night. In some cases, persons with primary hypersomnia have difficulty waking in the morning and may appear confused or angry. This condition is sometimes called sleep drunkenness and is more common in males. The number of people with primary hypersomnia is unknown, although 5–10% of people in sleep disorder clinics have the disorder. Primary hypersomnia usually affects young adults between the ages of 15 and 30.

Nocturnal myoclonus and restless legs syndrome (RLS) can cause either insomnia or hypersomnia in adults. Individuals with nocturnal myoclonus wake up because of cramps or twitches in the calves. These people feel sleepy the next day. Nocturnal myoclonus is sometimes called periodic limb movement disorder. RLS patients have a crawly or aching feeling in their calves that can be relieved by moving or rubbing the legs. RLS often prevents people from falling asleep until the early hours of the morning, when the condition is less intense.

Kleine-Levin syndrome is a recurrent form of hypersomnia that affects a person three or four times a year. Doctors do not know the cause of this syndrome. It is marked by two to three days of sleeping 18–20 hours per day, hypersexual behavior, compulsive eating, and irritability. Men are three times more likely than women to have the syndrome. As of 2001, there is no cure for this disorder.

Narcolepsy is a dyssomnia characterized by recurrent "sleep attacks" that a person cannot fight. The sleep attacks are about 10–20 minutes long. A person feels refreshed by the sleep, but typically feels sleepy again several hours later. Narcolepsy has three major symptoms in addition to sleep attacks: cataplexy, hallucinations, and sleep paralysis . Cataplexy is the sudden loss of muscle tone and stability ("drop attacks"). Hallucinations may occur just before falling asleep (hypnagogic) or right after waking up (hypnopompic) and are associated with an episode of REM sleep. Sleep paralysis occurs during the transition from being asleep to waking up. About 40% of patients with narcolepsy have or have had another mental disorder. Although narcolepsy is often regarded as an adult disorder, it has been reported in children as young as three years old. Almost 18% of people with narcolepsy are 10 years old or younger. It is estimated that 0.02–0.16% of the general population suffers from narcolepsy. Men and women are equally affected.

Breathing-related sleep disorders are syndromes in which a person's sleep is interrupted by problems with breathing. There are three types of breathing-related sleep disorders:

  • Obstructive sleep apnea syndrome. This is the most common form of breathing-related sleep disorder, marked by episodes of blockage in the upper airway during sleep. It is found primarily in obese people. Persons with this disorder typically alternate between periods of snoring or gasping (when their airway is partly open) and periods of silence (when their airway is blocked). Very loud snoring is a clue to this disorder.
  • Central sleep apnea syndrome. This disorder is primarily found in elderly people with heart or neurological conditions that affect their ability to breathe properly. It is not associated with airway blockage and may be related to brain disease.
  • Central alveolar hypoventilation syndrome. This disorder is found most often in extremely obese people. Their airway is not blocked, but blood oxygen level is too low.
  • Mixed-type sleep apnea syndrome. This disorder combines symptoms of both obstructive and central sleep apnea.

Circadian rhythm sleep disorders are dyssomnias resulting from a discrepancy between a person's daily sleep and wake patterns and demands of social activities, shift work, or travel. The term circadian comes from a Latin word meaning daily. There are three circadian rhythm sleep disorders. Delayed sleep phase type is characterized by going to bed and arising later than most people. Jet lag type is caused by travel to a new time zone. Shift work type is caused by the schedule of a person's job. People who are ordinarily early risers appear to be more vulnerable to jet lag and shift work-related circadian rhythm disorders than people who are "night owls." There are some individuals who do not fit the pattern of these three disorders and appear to be the opposite of the delayed sleep phase type. These people have an advanced sleep phase pattern and cannot stay awake in the evening, but wake up on their own in the early morning.

PARASOMNIAS. Parasomnias are primary sleep disorders in which a person's behavior is affected by specific sleep stages or transitions between sleeping and waking. They are sometimes described as disorders of physiological arousal during sleep.

Nightmare disorder is a parasomnia in which a person is repeatedly awakened from sleep by frightening dreams and is fully alert on awakening. The actual rate of occurrence of nightmare disorder is unknown. Approximately 10–50% of children between three and five years old experience nightmares. They occur during REM sleep, usually in the second half of the night. A child is usually able to remember the content of the nightmare and may be afraid to go back to sleep. More females than males have this disorder, but it is not known whether the gender difference reflects a difference in occurrence or a difference in reporting. Nightmare disorder is most likely to occur in children or adults under severe or traumatic stress .

Sleep terror disorder is a parasomnia in which a person awakens screaming or crying. The individual also has physical signs of arousal, like sweating, shaking, etc. It is sometimes referred to as pavor nocturnus. Unlike nightmares, sleep terrors typically occur in stage 3 or stage 4 NREM sleep during the first third of the night. A person may be confused or disoriented for several minutes and cannot recall the content of the dream. There is usually a return to sleep without being able to remember the episode the next morning. Sleep terror disorder is most common in children four to 12 years old and is out-grown in adolescence. It affects about 3% of children. Fewer than 1% of adults have the disorder. In adults, it

usually begins between the ages of 20 and 30. In children, more males than females have the disorder. In adults, men and women are equally affected.

Sleepwalking disorder, which is sometimes called somnambulism, occurs when a person is capable of complex movements during sleep, including walking. Like sleep terror disorder, sleepwalking occurs during stage 3 and stage 4 NREM sleep during the first part of the night. If individuals are awakened during a sleepwalking episode, they may be disoriented and have no memory of the behavior. In addition to walking around, persons with sleepwalking disorder have been reported to eat, use the bathroom, unlock doors, or talk to others. It is estimated that 10–30% of children have at least one episode of sleepwalking. However, only 1-5% meet the criteria for sleepwalking disorder. The disorder is most common in children eight to 12 years old. It is unusual for sleepwalking to occur for the first time in adults.

Unlike sleepwalking, REM sleep behavior disorder occurs later in the night and people can remember what they were dreaming. The physical activities of such persons are often violent.

Sleep disorders related to other conditions

In addition to the primary sleep disorders, the DSMIV-TR specifies three categories of sleep disorders that are caused by or related to substance use or other physical or mental disorders.

Many mental disorders, especially depression or one of the anxiety disorders, can cause sleep disturbances. Psychiatric disorders are the most common cause of chronic insomnia.

Some people with chronic neurological conditions like Parkinson's disease or Huntington's disease may develop sleep disorders. Sleep disorders have also been associated with viral encephalitis, brain disease, and hypo-or hyperthyroidism.

The use of drugs, alcohol, and caffeine frequently produce disturbances in sleep patterns. Alcohol abuse is associated with insomnia. A person may initially feel sleepy after drinking, but wakes up or sleeps fitfully during the second half of the night. Alcohol can also increase the severity of breathing-related sleep disorders. With amphetamines or cocaine, a person typically suffers from insomnia during drug use and hypersomnia during drug withdrawal. Opioids usually make short-term users sleepy. However, long-term users develop tolerance and may suffer from insomnia.

In addition to alcohol and drugs that are abused, a variety of prescription medications can affect sleep patterns. These medications include antihistamines , corticosteroids , asthma medicines, and drugs that affect the central nervous system .

Sleep disorders in children and adolescents

Pediatricians estimate that 20–30% of children have difficulties with sleep that are serious enough to disturb their families. Although sleepwalking and night terror disorder occur more frequently in children than in adults, children can also suffer from narcolepsy and sleep apnea syndrome.

Causes and symptoms

The causes of sleep disorders have already been discussed with respect to the DSM-IV-TR classification of these disorders.

The most important symptoms of sleep disorders are insomnia and sleepiness during waking hours. Insomnia is by far the more common of the two symptoms. It covers a number of different patterns of sleep disturbance. These patterns include inability to fall asleep at bedtime, repeated awakening during the night, and/or inability to go back to sleep once awakened.

Diagnosis

Diagnosis of sleep disorders usually requires a psychological history as well as a medical history. With the exception of sleep apnea syndromes, physical examinations are not usually revealing. A person's gender and age are useful starting points in assessing the problem. A doctor may also talk to other family members to obtain information about a person's symptoms. A family's observations are particularly important to evaluate sleepwalking, kicking in bed, snoring loudly, or other behaviors that an individual cannot remember.

Sleep logs

Many doctors ask people to keep a sleep diary or sleep log for a minimum of one to two weeks in order to evaluate the severity and characteristics of the sleep disturbance. An individual records medications taken as well as the length of time spent in bed, the quality of the sleep, and similar information. Some sleep logs are designed to indicate circadian sleep patterns as well as simple duration or restfulness of sleep.

Psychological testing

A physician may use psychological tests or inventories to evaluate insomnia because it is frequently associated with mood or affective disorders. The Minnesota Multiphasic Personality Inventory (MMPI), the Millon Clinical Multiaxial Inventory (MCMI), the Beck Depression Inventory, and the Zung Depression Scale are the tests most commonly used in evaluating this symptom.

Self-report tests

The Epworth Sleepiness Scale, a self-rating form recently developed in Australia, consists of eight questions used to assess daytime sleepiness. Scores range from 0–24, with scores higher than 16 indicating severe daytime sleepiness.

Laboratory studies

If a doctor is considering breathing-related sleep disorders, myoclonus, or narcolepsy as possible diagnoses, an affected person may be tested in a sleep laboratory or at home with portable instruments.

POLYSOMNOGRAPHY. Polysomnography can be used to help diagnose sleep disorders as well as conduct research into sleep. In some cases a person is tested in a special sleep laboratory. The advantage of this testing is the availability and expertise of trained technologists, but it is expensive. As of 2001, however, portable equipment is available for home recording of certain specific physiological functions.

MULTIPLE SLEEP LATENCY TEST. The multiple sleep latency test (MSLT) is frequently used to measure the severity of a person's daytime sleepiness. The test measures sleep latency (the speed with which an individual falls asleep) during a series of planned naps during the day. The test also measures the amount of REM sleep that occurs. Two or more episodes of REM sleep under these conditions indicates narcolepsy. This test can also be used to help diagnose primary hypersomnia.

REPEATED TEST OF SUSTAINED WAKEFULNESS. The repeated test of sustained wakefulness (RTSW) measures sleep latency by challenging a person's ability to stay awake. In the RTSW, a person is placed in a quiet room with dim lighting and is asked to stay awake. As with the MSLT, the testing pattern is repeated at intervals during the day.

Treatment

Treatment for a sleep disorder depends on what is causing the disorder. For example, if major depression is the cause of insomnia, then treatment of the depression with antidepressants should resolve the insomnia.

Medications

Sedative or hypnotic medications are generally recommended only for insomnia related to a temporary stress (such as surgery or grief) because of the potential for addiction or overdose . Trazodone, a sedating antidepressant, is often used for chronic insomnia that does not respond to other treatments. Sleep medications may also cause problems for elderly persons because of possible interactions with their other prescription medications. Among the safer hypnotic agents are lorazepam, temazepam, and zolpidem. Chloral hydrate is often preferred for short-term treatment in elderly people because of its mildness. Short-term treatment is recommended because this drug may be habit forming.

Narcolepsy is treated with stimulants such as dextroamphetamine sulfate or methylphenidate. Nocturnal myoclonus has been successfully treated with clonazepam.

Children with sleep terror disorder or sleepwalking are usually treated with benzodiazepines because this type of medication suppresses stage 3 and stage 4 NREM sleep.

Psychotherapy

Psychotherapy is recommended for persons with sleep disorders associated with other mental disorders. In many cases an individual's scores on the Beck or Zung inventories will suggest the appropriate direction of treatment.

Sleep education

"Sleep hygiene" or sleep education for sleep disorders often includes instructing a person in methods to enhance sleep. People are advised to:

  • Wait until they feel sleepy before going to bed.
  • Avoid using the bedroom for work, reading, or watching television.
  • Get up at the same time every morning no matter how much or how little they have slept.
  • Avoid smoking and avoid drinking liquids with caffeine.
  • Get some physical exercise on a daily basis, early in the day.
  • Limit fluid intake after dinner; in particular, avoid alcohol because it frequently causes interrupted sleep.
  • Learn to meditate or practice relaxation techniques.• Avoid tossing and turning in bed; instead, people should get up and listen to relaxing music or read.

Lifestyle changes

People with sleep apnea or hypopnea are encouraged to stop smoking, avoid alcohol or drugs of abuse, and lose weight in order to improve the stability of the upper airway.

In some cases, individuals with sleep disorders related to jet lag or shift work may need to change employment or travel patterns. They may need to avoid rapid changes in shifts at work.

Children with nightmare disorder may benefit from limits on television or movies. Violent scenes or frightening science fiction stories appear to influence the frequency and intensity of children's nightmares.

Surgery

Although making a surgical opening into the wind-pipe (a tracheostomy) for sleep apnea or hypopnea in adults is a treatment of last resort, it is occasionally performed if a person's disorder is life threatening and cannot be treated by other methods. In children and adolescents, surgical removal of the tonsils and adenoids is a fairly common and successful treatment for sleep apnea. Most people with sleep apnea are treated with continuous positive airway pressure (CPAP). Sometimes an oral prosthesis is used for mild sleep apnea.

Alternative treatment

Some alternative approaches may be effective in treating insomnia caused by anxiety or emotional stress. Meditation practice, breathing exercises, and yoga can break the vicious cycle of sleeplessness, worry about inability to sleep, and further sleeplessness for some people. Yoga can help some people to relax muscular tension in a direct fashion. The breathing exercises and meditation can keep them from obsessing about sleep.

Homeopathic practitioners recommend that people with chronic insomnia see a professional homeopath. They do, however, prescribe specific remedies for at-home treatment of temporary insomnia: Nux vomica for alcohol or substance-related insomnia, Ignatia for insomnia caused by grief, Arsenicum for insomnia caused by fear or anxiety, and Passiflora for insomnia related to mental stress.

Melatonin has also been used as an alternative treatment for sleep disorders. Melatonin is produced in the body by the pineal gland at the base of the brain. This substance is thought to be related to the body's circadian rhythms.


KEY TERMS


Apnea —The temporary absence of breathing. Sleep apnea consists of repeated episodes of temporary suspension of breathing during sleep.

Cataplexy —Sudden loss of muscle tone (often causing a person to fall), usually triggered by intense emotion. It is regarded as a diagnostic sign of narcolepsy.

Circadian rhythm —Any body rhythm that recurs in 24-hour cycles. The sleep-wake cycle is an example of a circadian rhythm.

Dyssomnia —A primary sleep disorder in which the patient suffers from changes in the quantity, quality, or timing of sleep.

Electroencephalogram (EEG) —The record obtained by a device that measures electrical impulses in the brain.

Hypersomnia —An abnormal increase of 25% or more in time spent sleeping. Patients usually have excessive daytime sleepiness.

Hypnotic —A medication that makes a person sleep.

Hypopnea —Shallow or excessively slow breathing usually caused by partial closure of the upper airway during sleep, leading to disruption of sleep.

Insomnia —Difficulty in falling asleep or remaining asleep.

Jet lag —A temporary disruption of the body's sleep-wake rhythm following high-speed air travel across several time zones. Jet lag is most severe in people who have crossed eight or more time zones in 24 hours.

Kleine-Levin syndrome —A disorder that occurs primarily in young males, three or four times a year. The syndrome is marked by episodes of hypersomnia, hypersexual behavior, and excessive eating.

Narcolepsy —A life-long sleep disorder marked by four symptoms: sudden brief sleep attacks, cataplexy, temporary paralysis, and hallucinations. The hallucinations are associated with falling asleep or the transition from sleeping to waking.

Nocturnal myoclonus —A disorder in which the patient is awakened repeatedly during the night by cramps or twitches in the calf muscles. Nocturnal myoclonus is sometimes called periodic limb movement disorder (PLMD).

Non-rapid eye movement (NREM) sleep —A type of sleep that differs from rapid eye movement (REM) sleep. The four stages of NREM sleep account for 75–80% of total sleeping time.

Parasomnia —A primary sleep disorder in which a person's physiology or behaviors are affected by sleep, the sleep stage, or the transition from sleeping to waking.

Pavor nocturnus —Another term for sleep terror disorder.

Polysomnography —Laboratory measurement of a person's basic physiological processes during sleep. Polysomnography usually measures eye movement, brain waves, and muscular tension.

Primary sleep disorder —A sleep disorder that cannot be attributed to a medical condition, another mental disorder, or prescription medications or other substances.

Rapid eye movement (REM) sleep —A phase of sleep during which a person's eyes move rapidly beneath the lids. It accounts for 20–25% of sleep time. Dreaming occurs during REM sleep.

REM latency —After a person falls asleep, the amount of time it takes for the first onset of REM sleep.

Restless legs syndrome (RLS) —A disorder in which a person experiences crawling, aching, or other disagreeable sensations in the calves that can be relieved by movement. RLS is a frequent cause of difficulty falling asleep at night.

Sedative —A medication given to calm agitated individuals; sometimes used as a synonym for hypnotic.

Sleep latency —The amount of time that it takes to fall asleep. Sleep latency is measured in minutes and is important in diagnosing depression.

Somnambulism —Another term for sleepwalking.


Practitioners of Chinese medicine usually treat insomnia as a symptom of excess yang energy. Cinnabar is recommended for chronic nightmares. Either magnetic magnetite or "dragon bones" is recommended for insomnia associated with hysteria or fear. If the insomnia appears to be associated with excess yang energy arising from the liver , a practitioner will suggest oyster shells. Acupuncture treatments can help bring about balance and facilitate sleep.

Dietary changes such as eliminating stimulant foods (coffee, cola, chocolate) and late-night meals or snacks can be effective in treating some sleep disorders. Nutritional supplementation with magnesium, as well as botanical medicines that calm the nervous system, can also be helpful. Among the botanical remedies that may be effective for sleep disorders are valerian (Valeriana officinalis), passionflower (Passiflora incarnata), and skullcap (Scutellaria lateriflora).

Prognosis

Prognosis depends on the specific disorder. Children usually outgrow sleep disorders. People with Kleine-Levin syndrome usually get better by age 40. Narcolepsy is a life-long disorder. The prognosis for sleep disorders related to other conditions depends on successful treatment of the substance abuse, medical condition, or other mental disorder. The prognosis for primary sleep disorders is affected by many things, including a person's age, gender, occupation, personality characteristics, family circumstances, neighborhood environment, and similar factors.

Health care team roles

Sleep experts are often trained in physiology, medicine or psychology. Such professionals often administer tests and make initial diagnoses. Physicians prescribe drugs for some forms of sleep disorders. Surgeons are occasionally called upon for surgical intervention. Nurses take part in any testing as well as providing pre-test patient education . Family members are often key members of a health care team when they provide information and help to make changes in the home. An affected person may become a member of the health care team when making dietary modifications, seeking alternative employment or deciding to undertake a course of therapy.

Prevention

Sleep disorders are difficult to prevent. Recognition of potential causes and avoidance of such situations or substances can prevent many forms of sleep disorders. Since many sleep disorders are relatively common and transitory, a good attitude about occasional problems with sleep is very helpful. This can prevent worrying.

Resources

BOOKS

American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders DSM-IV-TR. Chicago: American Psychiatric Association Press, 2000.

Culebras, Antonio. Sleep Disorders and Neurological Disease. New York: Marcel Dekker, 1999.

Dement, William, and Christopher Vaughn. The Promise of Sleep. New York: Delacorte Press, 1999.

Jenkins, Renee R. "Sleep disorders." In Nelson Textbook of Pediatrics, 16th ed., edited by Richard E. Behrman, et al. Philadelphia: Saunders, 2000, 572.

Rosen, Carol L., and Gabriel G. Haddad. "Obstructive sleep apnea and hypoventilation in children." In Nelson Textbook of Pediatrics, 16th ed., edited by Richard E. Behrman, et al. Philadelphia: Saunders, 2000, 1268-1271.

Shneerson, John. Handbook of Sleep Medicine. New York: Blackwell, 2000.

Simon, Roger, and Maria Sunseri. "Disorders of sleep and arousal." In Cecil Textbook of Medicine, 21st Ed., edited by Goldman, Lee Goldman and J. Claude Bennett. Philadelphia: Saunders, 2000.

Thorpy, Michael, and Yager, Jan. The Encyclopedia of Sleep and Sleep Disorders, 2nd Ed. New York: Facts on File, 2001.

PERIODICALS

Phillips, B., Ancoli-Israel S. "Sleep disorders in the elderly." Sleep Medicine, 2, no. 2 (2001): 99-114.

Richards, K.C., O'Sullivan P.S., Phillips RL. "Measurement of sleep in critically ill patients." Journal of Nursing Measurement no. 2 (2000): 131-144.

Santiago, JR, Nolledo M.S., Kinzler W., Santiago TV. "Sleep and sleep disorders in pregnancy." Annals of Internal Medicine 134, no. 5 (2001): 396-408.

Sateia, M.J., Greenough G., Nowell P. "Sleep in neuropsychiatric disorders." Seminars in Clinical Neuropsychiatry 5, no. 4 (2000): 227-237.

Werra, R. "Restless legs syndrome."American Family Physician 63, no. 6 (2001): 1048.

ORGANIZATIONS

American Academy of Neurology. 1080 Montreal Avenue, St. Paul, MN 55116, (651)-695-1940. <http://www.aan.com/resources.html>[email protected]

American Academy of Sleep Medicine. 6301 Bandel Road NW, Suite 101, Rochester, MN 55901. (507) 287-6006, Fax: (507) 287-6008. <http://www.asda.org/>. [email protected]

American Psychiatric Association. 1400 K Street NW, Washington, DC 20005. (888) 357-7924, Fax: (202) 682-6850. <http://www.psych.org/>. [email protected]

OTHER

Columbia Presbyterian medical Center. <http://cpmcnet.columbia.edu/dept/sleep/>.

Mayo Clinic. <http://www.mayo.edu/geriatrics-rst/Sleep_ToC.html>.

National Institutes of Health, National Center on Sleep Disorders Research. <http://www.nhlbi.nih.gov/about/ncsdr/index.htm>.

National Library of Medicine. <http://www.nlm.nih.gov/medlineplus/sleepdisorders.html>.

Sleep Medicine Home Page. <http://www.users.cloud9.net/~thorpy/>.

University of Washington School of Medicine. <http://depts.washington.edu/otoweb/sleepapnea.html>.

L. Fleming Fallon, Jr., MD, DrPH

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Sleep Disorders

Sleep disorders

Sleep disorders are chronic sleep irregularities, which drastically interfere with normal nighttime sleep or daytime functioning. Sleep-related problems are the most common complaint heard by doctors and psychiatrists, the two most common being insomnia (inability to go to sleep or stay asleep), and hypersomnia (excessive daytime sleepiness). While most people experience both problems at some time, it is only when they cause serious intrusions into daily living that they warrant investigation as disorders.

Sleep disorders research is a relatively new field of medicine stimulated by the discovery in 1953 of REM (rapid eye movement) sleep and the more recent discovery in the 1980s that certain irregular breathing patterns during sleep can cause serious illness and sometimes death. While medical knowledge of sleep disorders is expanding rapidly, clinical educational programs still barely touch on the subject, about which many physicians, psychiatrists and neurologists remain seriously undereducated.

Insomnias and hypersomnias

Insomnias include problems with sleep onset (taking longer than 30 minutes falling asleep), sleep maintenance (waking five or more times during the night or for a total of 30 minutes or more), early arousal (less than 6.5 hours of sleep over a typical night), light sleep, and conditioning (learning not to sleep by associating certain bedtime cues with the inability to sleep). Insomnias may be transient (lasting no longer than three weeks) or persistent. Most people experience transient insomnias, perhaps due to stress , excitement, illness, or even a sudden change to high altitude. These are treatable by short-term prescription drugs and, sometimes, relaxation techniques. When insomnia becomes persistent, it is usually classed as a disorder. Persistent insomnias may result from medical and/or psychiatric disorders, prescription drug use, and substance abuse, and often result in chronic fatigue, impaired daytime functioning, and hypersomnia.

Hypersomnias manifest as excessive daytime sleepiness, uncontrollable sleep attacks, and, in the extreme, causes people to fall asleep at highly inappropriate times, such as driving a car or when holding a conversation. Most hypersomnias, like narcolepsy and those associated with apnea (breathing cessation), are caused by some other disorder and are therefore symptomatic. Some, however, like idiopathic central nervous system (CNS) hypersomnia and Kleine-Levin syndrome , are termed "idiopathic" for their unknown origin. CNS hypersomnia causes a continuous state of sleepiness from which long naps and nighttime sleep provides no relief. This is usually a life-long disorder and treatment is still somewhat experimental and relatively ineffective. Kleine-Levin syndrome is a rare disorder seen three times as often in males as females, beginning in the late teens or twenties. Symptoms are periods of excessive sleepiness, excessive overeating, abnormal behavior , irritability, loss of sexual inhibition, and sometimes hallucinations. These periods may last days or weeks, occur one or more times a year, and disappear about the age of 40. Behavior between attacks is normal, and the sufferer often has little recall of the attack. Stimulant drugs may reduce sleepiness for brief periods, and lithium meets with some success in preventing recurrence.


Observation and classification of sleep disorders

Sleep abnormalities intrigued even the earliest medical writers who detailed difficulties that people experienced with falling asleep, staying asleep, or staying awake during the day. By 1885, Henry Lyman, a professor of neurology in Chicago, classified insomnias into two groups: those resulting from either abnormal internal or physical functions; or from external, environmental influences. In 1912, Sir James Sawyer reclassified the causes as either medical; or psychic, toxic, or senile. Insomnias were divided into three categories in 1927: inability to fall asleep, recurrent waking episodes, and waking earlier in the morning than appropriate. Another reclassification, also into three categories, was made in 1930: insomnia/hypersomnia, unusual sleep-wake patterns, and parasomnias (interruption of sleep by abnormal physical occurrences). One change to that grouping was made in 1930 when hypersomnias and insomnias became separate categories.

Intense escalation of sleep study in the 1970s saw medical centers begin establishing sleep disorder clinics where researchers increasingly uncovered abnormalities in sleep patterns and events. It was during this decade that sleep disorders became an independent field of medical research and the increasing number of sleep disorders being identified necessitated formal classification.

Dyssomnias

This group includes both insomnias and hypersomnias, and is divided into three categories: intrinsic, extrinsic, and circadian rhythm sleep disorders. Intrinsic sleep disorders originate within the body and include narcolepsy, sleep apnea, and periodic limb movements.

Narcolepsy is associated with REM sleep and the central nervous system. It causes frequent sleep disturbances and thus excessive daytime drowsiness. Subjects may fall asleep without warning, experience cataplexy—muscle weakness associated with sudden emotional responses like anger, which may cause collapse—and temporarily be unable to move right before falling asleep or just after waking up. While narcolepsy is manageable clinically and brief naps of 10-20 minutes may be somewhat refreshing, there is no cure.

Apnea is the brief cessation of breathing. Obstructive sleep apnea is caused by the collapse of the upper airway passages that prevent air intake, while central apnea occurs when the diaphragm and chest muscles cease functioning momentarily. Both apneas result in a suffocating sensation, which goes unnoticed but causes enough arousal to enable breathing to begin again. Bed partners report excessive snoring and repeated brief pauses in breathing. Apneas may disrupt sleep as many as several hundred times a night, naturally resulting in excessive daytime sleepiness. Severe episodes can actually cause death, usually from heart failure. Treatment for obstructive apnea includes pumping air through a nasal mask to keep air passages open, while some success in treating central apnea can be obtained with drugs and mechanical breathing aids.

Periodic limb movement (PLM) and restless leg syndrome (RLS) result in sleep disruptions and therefore hypersomnia. PLM occurs during sleep and subjects experience involuntary leg jerks (sometimes arms also). The subject is unaware of these movements but bed partners complain of being kicked and hit. In RLS, "crawling" or "prickling" sensations seriously interfere with sleep onset. Although their causes are yet unknown, certain drugs, stretching, exercise , and avoiding stress and excessive tiredness seem to provide some relief.

Extrinsic sleep disorders are caused by external influences such as drugs and alcohol , poor sleep hygiene, high altitude, and lack of regular sleep limit-setting for children.

Drug and alcohol-related sleep disorders result from stimulant, sedative, and alcohol use, all of which can affect, and severely disrupt, the sleep-wake schedule. Stimulants, including amphetamines , caffeine , and some weight loss agents, can cause sleep disturbances and may eventually result in a "crash" and the need for excessively long periods of sleep. Prolonged use of sedatives, including sleeping pills, often result in severe "rebound insomnia" and daytime sleepiness. Sudden withdrawal also produces these effects. Alcohol, while increasing total sleep time, also increases arousal, snoring, and the incidence and severity of sleep apnea. Prolonged abuse severely reduces REM and delta (slow-wave) sleep, and sudden withdrawal results in severe sleep-onset difficulties, significantly reduced delta sleep, and "REM rebound," causing intense nightmares and anxiety dreams for prolonged periods.

Circadian rhythm sleep disorders either affect or are affected by circadian rhythms, which determine our approximate 25-hour biological sleep-wake pattern and other biological functions. Disorders may be transient or permanent.

Jet-lag and shift work-related circadian rhythm Disorders are transient. Because our biological clock runs slightly slower than the 24-hour Sun clock, it must adjust to external time cues like alarm clocks and school or work schedules. Circadian rhythms must therefore "phase-advance" to fit the imposed 24-hour day. The body has difficulty phase-advancing more than one hour each day, therefore people undergoing drastic time changes after long-distance air travel suffer from "jet lag." Hypersomnia, insomnia, and a decrease in alertness and performance are not uncommon and may last up to ten days, particularly after eastward trips longer than six hours. Night-shift workers, whether permanent or alternating between day and night shifts, experience similar symptoms, which may become chronic because circadian rhythms induce maximum sleepiness during the Sunclock's night and alertness during the Sun-clock's day, regardless of how long a person works nights.

Delayed sleep phase syndrome is a chronic condition in which waking to meet normal daily schedules is extremely difficult. Such people are often referred to as "night people" because they feel alert late in the day and at night while experiencing fatigue and sleepiness in the mornings and early afternoons. This is because their biological morning is the middle of the actual night. Phase-delaying the sleep-wake schedule by going to bed three hours later and sleeping three hours longer until the required morning arousal time is reached, can often synchronize the two. Exposure to artificial, high-intensity, full spectrum light from about 7-9 a.m. often proves helpful.

Advanced sleep phase syndrome is much less prevalent and shows the reverse pathology to phase-delayed syndrome. Phase-advancing the sleep-wake schedule and light therapy during evening hours may prove helpful.


Parasomnias

Parasomnias are events caused by physical intrusions into sleep which are thought to be triggered by the central nervous system. These dysfunctions do not interfere with actual sleep processes and do not cause insomnia or hypersomnia. They appear more frequently in children than adults.

Arousal disorders appear to be associated with neurological arousal mechanisms. They usually occur early in the night during slow-wave rather than REM sleep and are therefore not the "acting out" of a dream.

Sleepwalking occurs during sleep. The subject may seem wide awake but displays a blank expression, seldom responds when spoken to, is difficult to awaken, moves clumsily, and sometimes bumps into objects, although they will often maneuver effectively around them. Some sleepwalkers perform dangerous activities, like driving a car. Although rarely the case with children, serious injuries can occur. Subjects displaying dangerous tendencies should take precautions like locking windows and doors. Episodes average about ten minutes, seldom occur more than once in any given night, and are seldom remembered.

Night or sleep terrors are sudden partial awakenings during non-REM sleep. Traditionally, a sufferer sits bolt upright in bed in a state of extreme panic, screams loudly, sweats heavily, and displays a rapid heart beat and dilated pupils. The patient will sometimes talk, and might even flee from bed in terror, often running into objects and causing injury. Episodes last about 15 minutes, after which sleep returns easily. There is seldom any recollection of the event. If woken, the subject may display violence and confusion and should, instead, be gently guided back to bed.

Rapid eye movement (REM) sleep parasomnias take place during sleep and include nightmares and the recently discovered REM sleep behavior disorder. This potentially injurious disorder is seen mostly in elderly men and results in aggressive behavior while sound asleep such as punching, kicking, fighting, and leaping from bed in an attempt to act out a dream. Subjects report their dreams, usually of being attacked or chased, become more violent and vivid over the years. Some sufferers even tie themselves into bed to avoid injury. Unfortunately, this disorder was seriously misdiagnosed until recently. It is now readily diagnosable and easily treated.

Sleep-wake transition disorders usually occur during transition from one sleep stage to another, or while falling asleep or waking up. Manifestations include sleeptalking, leg cramps, headbanging, hypnic jerks (sleep starts), and teeth-grinding.

Other parasomnias include excessive snoring, abnormal swallowing, bedwetting, sleep paralysis, and sudden unexplained death during sleep.


Diagnosis of sleep disorders

Identifying each specific sleep disorder is imperative for effective treatment, as treatment for one may adversely effect another. While sleeping pills may help in some instances, in others they exacerbate the problem. The most important step in diagnosis is the sleep history, a highly detailed diary of symptoms and sleep-wake patterns. The patient records events such as daily schedule; family history of sleep complaints; prescription or non-prescription drug use; and symptoms—when they occur, how long they last, their intensity, whether they are seasonal, what improves or worsens them, and effects of stress, family or environmental factors. Important contributors are family members or friends; for example, a bed partner or parent may be the only observer of unusual occurrences during the patient's sleep.

The sleeping brain—the new frontier

Many undiscovered secrets lie hidden behind the doors of sleep and its related disorders. However, the future looks bright for sufferers of sleep disorders. Intense interest from researchers, satisfaction of an increasing number of accurately diagnosed and treated patients, advances in technology, and the recent formation of a National Institute of Health Commission on Sleep by the United States Congress, suggest that research, training, education, and recognition in this area of medicine will continue to flourish.


Resources

books

Moorcroft, William H. Sleep, Dreaming and Sleep Disorders. Lanham/London: University Press of America, Inc., 1989.

Reite, Martin, Kim Nagel, and John Ruddy. Concise Guide to Evaluation and Management of Sleep Disorders. Washington, DC: American Psychiatric Press, Inc., 1990.

Thorpy, Michael J., ed. Handbook of Sleep Disorders. New York/Basel: Marcel Dekker, 1990.

Thorpy, Michael J., ed. International Classification of Sleep Disorders: Diagnostic and Coding Manual. Lawrence: Allen Press, 1990.

Yager, Jan, and Michael J. Thorpy. The Encyclopedia of Sleep and Sleep Disorders. New York: Facts on File, 1991.

periodicals

"Insomnia and Related Sleep Disorders." Psychiatric Clinics of North America, 16 (December 1993).

Marie L. Thompson

KEY TERMS

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Apnea

—Cessation of breathing.

Delta sleep

—Slow-wave, stage 4 sleep that normally occurs before the onset of REM sleep.

Extrinsic

—Caused by something on the outside.

Hypersomnia

—Excessive daytime sleepiness.

Idiopathic

—Disease of unknown origin.

Insomnia

—Inability to go to sleep or stay asleep.

Intrinsic

—Not dependent on external circumstances.

Parasomnia

—Interruption of sleep by abnormal physical occurrences.

Polysomnography

—Electronic monitoring equipment measuring brain waves, eye and muscle movement, heart rate, and other physiological functions.

REM sleep

—Rapid eye movement sleep that is characterized by dreaming, active brain activity, and numerous eye movements.

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