Anxiety

Definition

Anxiety in humans is variously defined as an emotion or a physiological condition. It can be understood as a complex response to an object or event that arouses apprehension. Anxiety involves biochemical and neuromuscular changes in the body, memories of past events (including personal history), anticipation of future events, and appraisal of the present situation. In contrast to fear, which is a reaction to an immediate external physical threat (such as a fire, a dangerous animal or person, or a sudden, sharp pain ), anxiety is an unpleasant state of uneasiness that may not have a clear or obvious present cause—it can arise before a threat materializes and persist after the threat has passed. While animals clearly experience fear, as far as is known only humans undergo anxiety.

Description

Anxiety as a biochemical response to stress

In humans, the biochemical response to a stressful or anxiety-provoking situation is known as the “fight-or-flight” reaction. It begins with the activation of a section of the brain called the hypothalamic-pituitaryadrenal system, or HPA. This system first causes the release of steroid hormones, which are also known as glucocorticoids. These hormones include cortisol, the primary stress hormone in humans.

The HPA system then releases a set of neurotransmitters called catecholamines. The catecholamines include dopamine, norepinephrine, and epinephrine (also known as adrenaline). These compounds have three important effects:

• Activation of the amygdala, an almond-shaped structure in the limbic system that triggers an emotional response of fear and anxiety.
• Signaling the hippocampus, another part of the limbic system, to store the emotional experience in long-term memory. Humans develop the capacity to experience anxiety at some point between the ages of three and five, when long-term memory begins to store negative past events; this storage then triggers worry about future recurrences.
• Suppressing activity in parts of the brain associated with short-term memory, concentration, and rational thinking. This suppression allows humans to react quickly to a stressful situation, but it also limits their ability to respond calmly and thoughtfully rather than emotionally.

Following the release of the catecholamines, a human's heart rate and blood pressure rise; the person breathes more rapidly, which allows the lungs to take in more oxygen. Blood flow to the muscles, lungs, and brain may increase by 300%–400%. The spleen releases more blood cells into the circulation, which increases the blood's ability to carry oxygen. The immune system redirects white blood cells to the skin, bone marrow, and lymph nodes; these are areas where injury or infection is most likely. At the same time, nonessential body systems shut down. The skin becomes cool and sweaty as blood is drawn away from it toward the heart and muscles. The mouth becomes dry, and the digestive system slows down; the person may feel queasy or nauseated.

Some degree of anxiety is adaptive in humans; it helps them to prepare for the future and devise strategies to prevent or lower the risk of dangerous or stressful situations. For example, a person who is anxious about a hurricane forecast is motivated to purchase food and secure their house or consider evacuating. On the other hand, too much anxiety is harmful because it interferes with psychological as well as physical functioning. If anxiety is not relieved within a reasonable period of time, the organ systems of the body do not have the opportunity to return fully to normal levels. Different organs become under- or overactivated on a long-term basis. In time, these abnormal levels of activity can damage the body.

State and trait anxiety

People vary in their susceptibility to anxiety on the basis of temperament and possibly other genetic factors. A psychologist named Spielberger introduced a useful distinction between what he called state and trait anxiety in the early 1970s. State anxiety refers to the unpleasant physical sensations associated with fear experienced in the face of a threat, as described earlier. The threat can be physical, psychological, or both. State anxiety implies a cognitive evaluation; a person experiencing this type of anxiety must believe on some level that a specific situation is in fact dangerous or threatening. Typically, the person feels less anxious after the stressful event is over.

Trait anxiety, on the other hand, refers to an aspect of personality—namely, a tendency to experience state anxiety when confronted with a threat—that remains stable in a specific individual over time but varies from one individual to another. In other words, some people are more susceptible than others to feel anxious in response to low-level threats or stressors.

Anxiety disorders

The experience of anxiety as such is not considered a mental disorder; it is usually described as a syndrome (cluster or group of symptoms) or condition. Long-term anxiety coupled with genetic vulnerability, however, leads to a number of disorders grouped together by the Diagnostic and Statistical Manual of Mental Disorders, fourth edition (DSM-IV) as anxiety disorders. These disorders are defined as conditions lasting six months or longer and as causing significant impairment in the patient's social or occupational functioning. They include:

• Panic disorder. Panic disorder is characterized by sudden episodes of intense anxiety accompanied by a pounding heart, sweatiness, weakness, faintness, or dizziness. The physical symptoms associated with panic disorder may cause the senior to think he or she is having a heart attack, is going crazy, or is about to die.
• Generalized anxiety disorder (GAD). GAD is one of the more common anxiety disorders among older adults. It is characterized by an anxious feeling that persists even though the anxiety may not have a specific focus or trigger. The person with GAD spends a lot of time worrying about everyday problems (family issues, money worries, minor health problems, etc.)
• Obsessive-compulsive disorder (OCD). People with OCD are afflicted by anxiety provoking thoughts, ideas, or impulses (obsessions) and by repetitive or ritualistic behaviors (compulsions) that are done to lessen the anxiety. Compulsions include such actions as repeated hand washing, counting items, checking door locks several times over, etc.
• Social phobia. Social phobia refers to extreme fear of social or performance-related situations to the point that functioning is impaired. The anxiety may be limited to a specific situation (such as public speaking) or it may extend to almost any activity outside the patient's family.
• Specific phobias. A specific phobia is an intense fear of an object or situation that does not ordinarily pose a real danger. Common phobias are fear of flying, small closed spaces (such as elevators or tunnels), water, dogs, high places, highway driving, bridges, and injuries involving blood. Most people with specific phobias recognize that their fear is excessive or unfounded.
• Post-traumatic stress disorder (PTSD). PTSD is an anxiety disorder in which an overwhelming traumatic event (criminal or terrorist attack, transportation disaster, natural disaster, etc.) is reexperienced in the form of flashbacks and nightmares. The person with PTSD typically avoids places or persons that remind them of the horrifying event.

Demographics

Primary anxiety disorders are common in the general adult population in North America. According to the National Institute of Mental Health (NIMH), about 40 million Americans, or 18 percent of the adult population, meet the criteria for an anxiety disorder in any given year. As far as is known, all races and ethnic groups are equally affected. The female: male ratio is about 3:2.

Seniors, however, are more likely to experience anxiety that does not meet the criteria of an anxiety disorder. Anxiety in older adults is more likely to be associated with depression , physical illness, bereavement, other life changes, dementia, or delirium rather than a primary anxiety disorder. It is relatively uncommon for seniors to develop anxiety disorders for the first time, with the exception of PTSD. The most common primary anxiety disorder in seniors is GAD, which may affect as many as 3 percent of older adults. PTSD can occur in adults in any age group exposed to a sufficiently traumatic event. OCD, social phobia, and panic disorder are more common in younger adults than in the elderly, and often become less severe with age.

Causes and symptoms

Causes

The causes of anxiety are the complex interactions between the human central nervous system, the human capacity to remember the past and anticipate the future, an individual's genetic susceptibility to stress, his or her life history, and specific situational cues or triggers.

Symptoms

People experiencing anxiety may have some or many of the following physical symptoms:

• Digestive system: dry mouth, nausea, vomiting, diarrhea, abdominal cramps.
• Respiratory system: dizziness, fainting, choking sensations, shortness of breath, difficulty breathing.
• Circulatory system: rapid pulse or heartbeat, irregular heart rhythms, headache, heavy sweating.
• Musculoskeletal system: muscle tension or cramps, chest pain, shakiness and impaired coordination, general fatigue, stiff or sore joints.
• Other: Insomnia, restlessness, pacing the floor.

Diagnosis

The diagnosis of anxiety is complicated by a number of factors. Because anxiety is a condition or syndrome rather than a disease or disorder in its own right, the doctor will need to distinguish between anxiety as a temporary response to a specific situation or event; anxiety as a symptom of a physical illness, dementia, a sleep disorder, drug or alcohol withdrawal, or a medication side effect; and anxiety as a symptom of a primary anxiety disorder.

History and physical examination

The senior's doctor will usually take the following steps:

• History-taking and interview. The doctor will ask the patient to describe his or her anxiety experiences, and will note whether they are acute (lasting hours to weeks) or persistent (lasting from months to years). A family history may be taken, as many anxiety disorders tend to run in families. The doctor may also give the patient a diagnostic questionnaire to evaluate the presence of anxiety disorders. The Hamilton Anxiety Scale is a commonly used instrument for evaluating anxiety in seniors.
• Medical evaluation. This step is necessary because new-onset anxiety in an older adult is frequently caused by such physical disorders as hyperthyroidism, Cushing's disease, mitral valve prolapse, carcinoid syndrome, and pheochromocytoma. The doctor will also observe the patient for such external physical signs of anxiety as sweating, tremor, speeded-up heartbeat, or rapid breathing. In addition, certain medications (steroids, digoxin, thyroxine, theophylline, and selective serotonin reuptake inhibitors or SSRIs) may also cause anxiety as a side effect. The senior should be asked about his or her use of coffee, tea, and herbal preparations as well, since beverages containing high levels of caffeine can cause jitteriness and anxious feelings in older adults.
• Substance abuse evaluation. Because anxiety is a common symptom of substance abuse and withdrawal syndrome, the doctor will ask about the patient's use of nicotine, alcohol, and other common substances (including prescription medications) that may be abused. In addition, some seniors use alcohol or other drugs as a form of self-treatment for underlying anxiety, so that the doctor will need to determine whether the anxiety is causing the alcohol or drug use, or the substance abuse is causing the anxiety.
• Evaluation for other psychiatric disorders. This step is necessary because of the frequent overlapping between anxiety and depression in older adults. In addition, some older adults meet the DSM-IV criteria for more than one anxiety disorder.

Laboratory tests

The doctor may order one or more blood or urine tests to rule out substance abuse disorders, disorders of the thyroid gland, HIV infection, or infections affecting the central nervous system (encephalitis, latestage syphilis, meningitis ). An electrocardiogram (ECG) or treadmill test may be given to rule out cardiac disorders.

Imaging studies

Imaging studies are usually performed only if the doctor needs to rule out brain tumors , an infection of the brain, a skull fracture, or other physical abnormalities that may be causing the anxiety.

Treatment

Medications

Medications are generally given to seniors whose anxiety is severe enough to interfere with their daily life:

• Benzodiazepines. This group of tranquilizers does not decrease worry, but lowers the senior's anxiety by decreasing muscle tension. The benzodiazepines have three major disadvantages, however: they carry a high risk of dependence; they cannot be given to seniors who abuse alcohol or other drugs; and they affect short-term memory. In addition, they can cause drowsiness and loss of coordination, which can increase the risk of falls.
• Tricyclic antidepressants. These drugs include imipramine (Tofranil), nortriptyline (Pamelor), and desipramine (Norpramin). Their major drawback for seniors is that, like the benzodiazepines, they increase the patient's risk of falls and other accidents.
• Selective serotonin reuptake inhibitors. Paroxetine (Paxil), one of the SSRIs, was approved by the Food and Drug Administration (FDA) in 2001 as a treatment for GAD. Venlafaxine (Effexor) is effective in treating patients whose anxiety symptoms are primarily somatic. It is important for seniors taking an SSRI not to discontinue the drug abruptly, as it increases the risk of suicide.

A newer drug, pregabalin (sold under the trade name Lyrica in the United States), has been approved by the Food and Drug Administration for the treatment of fibromyalgia and partial seizures. It is also approved in Europe (though not in the United States as of early 2008) for the treatment of GAD. Early trials indicate that pregabalin is effective in treating seniors with GAD; it has a low rate of interactions with other drugs, a low risk of dependence, and relieves anxiety symptoms more rapidly than the SSRIs. Its major drawback is an increased risk of drowsiness and loss of balance.

Patient education and psychotherapy

Patient education is an important first step in treating anxiety, whether or not the senior meets the formal criteria for an anxiety disorder. The doctor may have an office handout on anxiety or offer patient education materials from the Anxiety Disorders Association of America (ADAA) or the National Institute of Mental Health (NIMH). These brochures are written in a simple, easy-to-understand style and make it easier for the senior (or caregiver ) to ask the doctor questions about the senior's specific difficulties with anxiety and the doctor's treatment recommendations.

QUESTIONS TO ASK YOUR DOCTOR

• How can I tell whether worry or anxious feelings are appropriate or excessive?
• What are the indications that I may have an anxiety disorder?
• What actions or activities would you recommend for dealing with normal anxiety?

A number of evidence-based studies have found cognitive therapy to be effective in treating chronic anxiety. Relaxation training is another psychological intervention that has been shown to help seniors. The greatest benefit of cognitive therapy is its effectiveness in helping seniors with the disorder to learn more realistic ways to appraise their problems and to use better problem-solving techniques. As a rule, however, anxious patients who have concurrent personality disorders ; who are in the early stages of cognitive decline; who are living with chronic social stress (e.g., caring for a spouse with Alzheimer's disease or living in an unsafe neighborhood); or who don't trust psychotherapy require treatment with medications.

Exposure therapy is the treatment most commonly recommended for social phobia and specific phobias. In exposure therapy, the patient is gradually exposed to the object or situation that is feared, perhaps at first only through pictures or tapes, then later in real life. For example, a senior who is afraid of dogs may begin by looking at a picture of a dog, then watch a short video of a dog, then visit someone with a well-behaved pet dog, and finally touch or pet a dog. Often the therapist will accompany the person to a feared situation to provide support and guidance.

Family therapy is sometimes recommended for seniors who are living with an adult son or daughter and whose anxiety is causing stress for other members of the household.

Group therapy or informal anxiety support groups are also recommended for seniors with anxiety disorders. In many cases, social contact with others eases the isolation that often reinforces the senior's anxiety, and group members often have helpful tips about coping with the stresses that cause worry as well as with the worry itself.

Complementary and alternative (CAM) approaches

Several alternative and complementary therapies have been found helpful in treating patients with diagnosed anxiety disorders. These include hypnotherapy; music therapy; yoga; t'ai chi ; religious practice; mindfulness meditation; and guided imagery meditation. One herbal remedy that has been used in clinical trials for anxiety is passionflower (Passiflora incarnata). The researchers reported that passionflower extract was as effective as a benzodiazepine tranquilizer in relieving feelings of anxiety without the side effects of the prescription medication.

Nutrition/Dietetic concerns

The senior's eating patterns should be evaluated for adequate nutritional balance, regular mealtimes (no skipping meals), and high levels of caffeine intake. This evaluation is particularly important if the senior is abusing alcohol or other drugs to cope with anxiety, as substance abuse often leads to malnutrition in older adults. In some cases a vitamin B 12 supplement may help, as a deficiency of this vitamin causes anxiety and depression in some older people. Seniors who smoke should be encouraged to quit, as the nicotine in tobacco has a stimulant effect.

Regular physical exercise alongside a well-balanced diet is often recommended to relieve anxiety and counteract the effects of emotional stress on the body.

Therapy

Therapy for anxiety may include a short course of medication, longer-term psychotherapy, patient education, or a combination of all three. The doctor may also recommend relaxation techniques or other CAM approaches.

Prognosis

The prognosis of anxiety as a temporary response to a time-limited crisis is generally very good; most people, including seniors, return to a normal level of functioning within hours or a few days after the event has passed. The prognosis for recovery from an anxiety disorder depends on the specific anxiety disorder and its severity; the availability of family or social support; the senior's living situation; and the presence of other diseases or disorders, particularly chronic health conditions.

KEY TERMS

Amygdala —An almond-shaped brain structure in the limbic system that is activated in acute stress situations to trigger the emotion of fear.

Cortisol —A steroid hormone released by the cortex (outer portion) of the adrenal gland when a person is anxious.

Cue —A stimulus, either internal body sensations or an external event or object, that causes a learned response in an individual. Cues are sometimes called triggers.

Free-floating —A term used in psychiatry to describe anxiety that is unfocused or lacking an apparent cause or object.

Hippocampus —A curved ridge in the brain that is part of the limbic system. The hippocampus stores long-term memories of anxiety-provoking experiences.

Panic attack —An episode of intense fear, abrupt in onset, lasting for several minutes, and accompanied by physical symptoms and/or temporary cognitive disturbances. Panic attacks may be unexpected, or they may be cued.

Phobia —An unfounded or unrealistic dread of a specific object or situation that arouses feelings of panic.

State anxiety —The immediate physical sensations associated with perception of a threat and the resulting fear response.

Syndrome —A group of signs or symptoms that occur together and characterize a specific disease or condition.

Temperament —The dimension of an individual's personality that is rooted in genetic or biological factors.

Trait anxiety —An aspect of an individual's personality that influences their susceptibility to anxiety in stressful situations.

Worry —Mental distress or agitation, usually about something anticipated in the future.

Prevention

As of 2008, the genetic factors involved in trait anxiety or the DSM-IV anxiety disorders have not been fully identified. In addition, the many stressors of modern life that raise anxiety levels in older adults are difficult to escape or avoid. The best preventive strategy, given that trait anxiety may be innate and that chronic worrying often starts early in life, is for parents to model realistic assessment of stressful events and teach effective coping strategies to their children.

Caregiver concerns

Care givers of anxious seniors should be concerned about:

• The long-term effects of worry and anxiety on the senior's physical health.
• The impact of chronic anxiety or a diagnosed anxiety disorder on other family members. Many books on caring for seniors note that chronic worrying on the part of the older person can be stressful for others sharing a home with them.
• Suicidal ideation or completed suicide. Seniors suffering from depression along with anxiety or a diagnosed anxiety disorder are at increased risk of self-harm.
• Proper use of any medications prescribed for anxiety. Benzodiazepines carry a risk of addiction, abuse, or short-term memory loss, while sudden discontinuation of an SSRI may increase the senior's risk of suicide.

Resources

BOOKS

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

Beers, Mark H., M. D., and Thomas V. Jones, MD. Merck Manual of Geriatrics, 3rd ed., Chapter 34, “Anxiety Disorders.” Whitehouse Station, NJ: Merck, 2005.

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

Spielberger, C. D. Anxiety: Current Trends in Theory and Research: I. New York: Academic Press, 1972.

PERIODICALS

Ayers, C. R., et al. “Evidence-Based Psychological Treatments for Late-Life Anxiety.” Psychology and Aging 22 (March 2007): 8–17.

Kroenke, K., R. L. Spitzer, J. B. Williams, et al. “Anxiety Disorders in Primary Care: Prevalence, Impairment, Comorbidity, and Detection.” Annals of Internal Medicine 146 (March 6, 2007): 317–325.

Longo, Lance, and Brian Johnson. “Addiction: Part I. Benzodiazepines—Side Effects, Abuse Risk and Alternatives.” American Family Physician 61 (April 1, 2000): 2121–2128.

Shearer, Steven, and Lauren Gordon. “The Patient with Excessive Worry.” American Family Physician 73 (March 15, 2006): 1049–1056.

OTHER

National Institute of Mental Health (NIMH). Anxiety Disorders. NIH Publication No. 06-3879. Bethesda, MD: NIMH, 2006.

Xiong, Glen L., and James O. Bourgeois. “Hypochondriasis.” eMedicine, November 20, 2007. http://www.emedicine.com/med/topic3122.htm [cited March 21, 2008].

Yates, William R., MD. “Anxiety Disorders.” eMedicine, August 23, 2007. http://www.emedicine.com/med/topic152.htm [cited March 21, 2008].

ORGANIZATIONS

American Psychiatric Association, 1000 Wilson Boulevard, Suite 1825, Arlington, VA, 22209, (703) 907-7300, [email protected], http://www.psych.org/.

Anxiety Disorders Association of America (ADAA)., 8730 Georgia Avenue, Suite 600, Silver Spring, MD, 20910, (240) 485-1001, (240) 485-1035, http://www.adaa.org/.

National Alliance on Mental Illness (NAMI), Colonial Place Three, 2107 Wilson Blvd., Suite 300, Arlington, VA, 22201, (703) 524-7600, (800) 950-NAMI (6264), (703) 524-9094, http://www.nami.org/Hometemplate.cfm.

National Institute of Mental Health (NIMH), 6001 Executive Boulevard, Room 8184, MSC 9663, Bethesda, MD, 20892, (301) 443-4513, (866) 615-6464, (301) 443-4279, [email protected], http://www.nimh.nih.gov/index.shtml.

National Mental Health Association (NMHA), 2000 N. Beauregard Street, 6th Floor, Alexandria, VA, 22311, (703) 684-7722, (800) 969-NMHA, (703) 684-5968, http://www1.nmha.org/.

Rebecca J. Frey Ph.D.