Depression

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Depression

Definition

Depression is the general name for a family of illnesses known as depressive disorders. Depression is an illness that affects not only the mood and thoughts, but also the physical functions of affected individuals. Depressive disorders usually result from a combination of genetic, environmental, and psychological factors.

Description

Everyone feels sadness, grief, or despair at some point in their lives. However, unlike these normal, transient emotional states, a depressive disorder is not a temporary bout of "feeling down" but rather a serious disease that should be recognized and treated as a medical condition. Without treatment, a depressive disorder can persist and its symptoms can go on for weeks, months, or years. The three most common types of depression are dysthymia or dysthymic disorder, major depression, and bipolar disorder .

Depression is quite widespread and one of the leading causes of disability in the world. Commonly recognized symptoms of all types of depressive disorders are recurring feelings of sadness and guilt, changes in sleeping patterns such as insomnia or oversleeping, changes in appetite, decreased mental and physical energy, unusual irritability, the inability to enjoy once-favored activities, difficulty in working, and thoughts of death or suicide. If only these "down" symptoms are experienced, the individual may suffer from a unipolar depressive disorder such as dysthymia or major depression. If the depressed periods alternate with extreme "up" periods, the individual may have a bipolar disorder.

Dysthymia is a relatively mild depressive disorder that is characterized by the presence of two or more of the symptoms listed above. The symptoms are not severe enough to disable the affected individual, but are long-term (chronic), and may last for several years. Dysthymia is a compound word originating in Greek that means ill, or bad, (dys-) soul, mind, or spirit (thymia). Individuals affected with dysthymia often also experience episodes of major depression at some point in their lives.

In major depression, the affected individual has five or more symptoms and experiences one or more prolonged episodes of depression that last longer than two weeks. These episodes disrupt the ability of the affected individual to the point that the person is unable to function. Individuals experiencing an episode of major depression often entertain suicidal thoughts, the presence of which contribute to this disorder being quite serious. Major depression should not be confused with a grief reaction such as that associated with the death of a loved one. Some individuals affected by major depression may experience only a single bout of disabling depression in their lifetimes. More commonly, affected individuals experience recurrent disabling episodes throughout their lives.

Bipolar disorder, formerly called manic depression or manic-depressive illness, is not nearly as common as major depression and dysthymia. Bipolar disorder is associated with alternating periods of extreme excitement (mania) and periods of extreme sadness (depression). The rate of the transition between cycles is usually gradual, but the mood swings may also be severe and dramatically rapid. When in the depressive state, the bipolar disorder affected individual may show any or all of the common symptoms of depression. In the manic state, the bipolar disorder affected individual may feel restless and unnaturally elated, have an overabundance of confidence and energy, and be very talkative. Mania can distort social behavior and judgment, causing the affected individual to take excessive risks and perhaps make imprudent decisions that can have humiliating or damaging consequences. Without medical treatment, bipolar disorder may progress into psychosis.

Depressive disorders are believed to be related to imbalances in brain chemistry, particularly in relation to the chemicals that carry signals between brain cells (neurotransmitters) as well as the hormones released by parts of the brain. Serotonin and neuroepinephrine are two important neurotransmitters. Disruption of the brain's circuits in areas involved with emotions, appetite, sexual drive, and sleep is a likely cause of the dysfunctions associated with depressive disorders. Thus, some of the newest treatments for depression are drugs that are known to have an effect on brain chemistry.

Genetic profile

Depression is known to be genetically linked because it often runs in families and has been studied in identical twins, but the specific gene markers for depression remain elusive. In 2000, the National Institutes of Mental Health began enrolling patients in what became the largest clinical psychiatric genetic study ever attempted to investigate how recurrent depression is transmitted across generations. This study primarily focused on major depression and dysthymia.

In familial cases of bipolar disorder, the most widely implicated genetic regions are those of chromosome 18 and chromosome 21. However, other researchers have mapped bipolar disorder to chromosomes 11p, Xq28, 6p, and many others. From this evidence, it is possible that bipolar disorder is a multi-gene (polygenic) trait requiring a combination of 3 or more genes on separate chromosomes for the condition to be expressed. Further research is also ongoing to determine the genetic marker, or markers, for bipolar disorder.

It is understood that there are also many non-genetic factors that cause depression, including stressful environmental conditions, certain illnesses, and precipitating conditions such as the loss of a close relationship. Alcohol abuse and the use of sedatives, barbiturates, narcotics, or other drugs can cause depression due to their effect on brain chemistry.

Demographics

It is estimated that the likelihood of experiencing an episode of major depression during one's lifetime is 5%. Approximately 9.5% of the American population, or 19 million people, are affected by depression in any given year. Depression occurs worldwide, but more Americans are diagnosed with depression than inhabitants of any other country. These lower occurrences of diagnosis in other parts of the world might indicate a higher incidence of depression in Americans than in all other peoples, but it may also be the result of the stigma, or shame, often associated with the diagnosis of a psychological disorder. Depression is not generally linked to any particular race of people.

In the United States, women experience depression at a rate that is almost twice that of men. This may be partially explained by the greater willingness of women to seek psychological treatment, but this does not explain the entire discrepancy. Many physical events specific to women, such as menstruation, pregnancy, miscarriage, the post-partum period, and menopause are recognized as factors contributing to depression in women. Women in the United States may face environmental stresses with a higher frequency than men. Most single parent households are headed by women; women still provide the majority of child and elder care, even in two-income families; and women are generally paid less than men so financial concerns may be greater.

Particular demographic problems associated with depression are depression in the elderly and depression in children and adolescents. A common belief is that depression is normal in elderly people. This is not the case, although increasing age and the absence of interpersonal relationships are associated with higher rates of depression. Because of this misconception, depressive disorders in the elderly population often go undiagnosed and untreated. Similarly, many parents often ignore the symptoms of a depressive disorder in their children, assuming that these symptoms are merely a phase that the child will later outgrow.

Signs and symptoms

Individuals affected with depressive disorders display a wide range of symptoms. These symptoms vary in severity from person to person and vary over time in a single affected individual.

Symptoms that characterize a depressive state are: feelings of hopelessness, guilt, or worthlessness; a persistent sad or anxious mood; restlessness or irritability; a loss of interest in activities that were once considered pleasurable; difficulty concentrating, remembering, or making decisions; sleep disorders, including insomnia, early morning awakening, and/or oversleeping; constant fatigue; eating disorders, including weight loss or overeating; suicidal thoughts and/or tendencies; and persistent physical symptoms that do not respond to the normal treatments of these symptoms, such as headaches, digestive problems, and chronic pain.

Symptoms that characterize a manic state are: increased energy accompanied by a decreased need for sleep, a loss of inhibitions accompanied by inappropriate social behavior, excessive enthusiasm and verve, increased talking, poor judgment, a feeling of invincibility, grandiose thinking and ideas, unusual irritability, and increased sexual desire.

Diagnosis

Depression is notoriously difficult to diagnose because its symptoms are not readily apparent to the medical professional unless the patient first recognizes and admits to them. Once the individual seeks help for his or her symptoms, the first step in the diagnosis of a depressive disorder is a complete physical examination to rule out any medical conditions, viral infections, or currently used medications that may produce the effects also seen in depression. Alcohol or other drug abuse as a possible cause of the observed symptoms should also be investigated. Once a physical basis for these symptoms is eliminated, a complete psychological exam should be undertaken. This examination consists of a mental status examination; a complete history of both current and previously experienced symptoms; and a family history.

The mental status examination is used to determine if a more severe psychotic condition is evident. This mental status examination will also determine whether the depressive disorder has caused changes in speech or thought patterns or memory that may indicate the presence of a depressive disorder. The complete psychological exam also includes a complete history of the symptoms being experienced by the affected individual. This history includes the onset of the symptoms, their duration, and whether or not the affected individual has had similar symptoms in the past. In the case of past symptoms, a treatment history should be completed to assess whether these symptoms previously responded to treatment, and if so, which treatments were effective. The final component of the complete psychological exam is the family history. In cases where the affected individual has had similarly affected family members a treatment history should also be completed, as much as possible, for these family members.

Treatment and management

Treatment of depression is on a case-by-case basis that is largely dependent on the outcome of the psychological

examination. Some mildly affected individuals respond fully to psychotherapy and do not require medication. Some individuals affected with moderate or severe depression benefit from antidepressant medication. Most affected individuals respond best to a combination of antidepressant medication and psychotherapy: the medication to provide relatively rapid relief from the symptoms of depression and the psychotherapy to learn effective ways to manage and cope with problems and issues that may cause the continuation of symptoms or the onset of new symptoms of depression.

Various types of antidepressant medications are available for the treatment of depressive disorders. Many individuals affected by depression will go through a variety of antidepressants, or antidepressant combinations, before the best medication and dosage for them is identified. Almost all antidepressant medications must be taken regularly for at least two months before the full therapeutic effects are realized. A full course of medication is generally no shorter than six to nine months to prevent recurrence of the symptoms. In individuals affected with bipolar disorder or chronic major depression, medication may have to be continued throughout the remainder of their lives. These time-related conditions often pose problems in the management of individuals affected with depressive disorder. Many individuals who have a depressive disorder discontinue their medications before the fully prescribed course, for a variety of reasons. Some affected individuals feel side effects of the medications prior to feeling any benefits; others do not feel that the medication is helping because of the delay between the initiation of the treatment and the feelings of symptom relief; and, many feel better prior to the full course and so cease taking the medication.

The three most commonly prescribed antidepressant drug classes consist of the older tricyclics (TCAs) and the two relatively new drug classes: the selective serotonin reuptake inhibitors (SSRIs) and the monoamine oxidase inhibitors (MAOIs). The most common TCAs are amitriptyline (Elavil), clomipramine (Anafranil), desipramine (Norpramin, Pertofrane), doxepin (Sinequan, Adapin), imipramine (Tofranil, Janimine), nortriptyline (Pamelor, Aventyl), protriptyline (Vivactil), and trimipramine (Surmontil). The most common SSRIs are: citalopram (Celexa), fluoxetine (Prozac), fluvoxamine (Luvox), paroxetine (Paxil), and sertraline (Zoloft). The most common MAOIs are: phenelzine (Nardil) and tranylcypromine (Parnate).

Many antidepressant medications cause side effects such as agitation, bladder problems, blurred vision, constipation, drowsiness, dry mouth, headache, insomnia, nausea, nervousness, or sexual problems. Most of these side effects wear off as the treatment course progresses. The tricyclics cause more severe side effects than the newer SSRIs or MAOIs.

St. John's wort is an herbal remedy that has been widely used to treat depressive disorders. In Germany, this herbal remedy is used more than any other antidepressant. No scientific studies have been completed on the long-term effects of St John's wort in the treatment of depression. In 2000, the National Institutes of Health (NIH) completed patient enrollment in a three-year clinical study to study this herbal treatment of depression.

In the most severely affected individuals, or where antidepressant medications either have not worked or cannot be taken, electroconvulsive therapy (ECT) may be considered. In the ECT procedure, electrodes are put on specific locations on the head to deliver electrical stimulation to the brain. This electrical stimulation is designed to trigger a brief seizure within the brain. These seizures generally last approximately 30 seconds and are not consciously felt by the patient. ECT has been much improved in recent years; it is no longer the electro-shock treatment of nightmares, and its deleterious effects on long-term memory have been reduced. ECT treatments are generally administered several times a week as necessary to control the symptoms being experienced.

Several short-term (10 to 20 week) psychotherapies have also been demonstrated to be effective in the treatment of depressive disorders. These include interpersonal and cognitive/behavioral therapies. Interpersonal therapies focus on the interpersonal relationships of the affected individual that may both cause and heighten the depression. Cognitive/behavioral therapies focus on how the affected individual may be able to change his or her patterns of thinking or behaving that may lead to episodes of depression. Psychodynamic therapies, which generally are not short-term psychotherapies, seek to treat the individual with a depressive disorder through a resolution of internal conflicts. Psychodynamic therapies are generally not initiated during major depression episodes or until the symptoms of depression are significantly improved by medication or one of the short-term psychotherapies.

Prognosis

Over 80% of individuals affected with a depressive disorder have demonstrated improvement after receiving the appropriate combination of treatments. A significant tragedy associated with depression is the failure of many affected individuals to realize that they have a treatable medical condition. Some affected individuals who do not receive treatment may recover completely on their own, but most will suffer needlessly. A small number of individuals with depressive disorder do not respond to treatment.

Resources

BOOKS

Appleton, William. Prozac and the New Antidepressants: What You Need to Know About Prozac, Zoloft, Paxil, Luvox, Wellbutrin, Effexor, Serzone, and More. New York: Plume, 2000.

Beck, Aaron, and Brian Shaw. Cognitive Theory of Depression. New York: Guilford Press, 1987.

Papolos, Demitri, and Janice Papolos. Overcoming Depression, 3rd ed. New York: Guilford Press, 1997.

PERIODICALS

Cytryn, L. "The cutting edge of sadness." Psychiatric Times (October 1996).

Kelsoe, G. "An update on the search for genes for bipolar disorder." Psychiatric Times (September 1996).

Nemeroff, C. "The neurobiology of depression." Scientific American (June 1998): 42-9.

ORGANIZATIONS

National Depressive and Manic Depressive Association. 730 N. Franklin, Suite 501, Chicago, IL 60610-7204. (800) 826-3632 or (312) 642-7243. <http://www.ndmda.org>.

National Foundation for Depressive Illness, Inc. PO Box 2257, New York, NY 10016. (212) 268-4260 or (800) 239-1265. <http://www.depression.org>.

National Institute of Mental Health. 6001 Executive Blvd., Rm. 8184, MSC 9663, Bethesda, MD 20892-9663. (301) 443-4513. Fax: (301) 443-4279. <http://www.nimh.nih.gov/publicat/index.cfm>.