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Depressive disorders are illnesses that involve the body, mood and thoughts¹. Everyone feels sad sometimes; this is a natural response to loss and to life's challenges and disappointments. However, if the feeling of sadness becomes intense, lasts for a long period of time and prevents a person from leading a normal life, it is a depressive disorder and one of several depressive illnesses.

According to a report from the U.S. National Institutes of Mental Health, nearly 18.8 million American adults suffer from major depression². Furthermore, suicide, which is closely linked to depression, is the third leading cause of death in people aged 10 to 24 years old. Older Americans are also affected by depression and suicide. Although people aged 65 and older comprise only 12 percent of the U.S. population, they accounted for 16 percent of suicide deaths in 2004³. Surprisingly, studies show that many older adults (up to 75 percent) who committed suicide visited a physician within a month prior to death⁴. Depression is not always recognized and left undiagnosed and untreated, it can worsen, lasting for months or years and causing untold suffering.

There are several types of depressive disorders, and within each type there are variations in the severity and persistence of the symptoms. Major depression may involve a variety of symptoms such as a persistent sad or anxious mood, pessimism, feelings of guilt or helplessness, loss of interest in activities that were once enjoyed, fatigue, insomnia, loss of appetite or overeating, thoughts of death/suicide and restlessness, as well as persistent physical symptoms such as headaches that do not respond to treatment⁵. The symptoms of major depression are disabling and interfere with a person's ability to work, study, sleep, eat and enjoy activities that were once pleasurable.

Dysthymia, a less severe type of depression, is manifested by long-term, chronic symptoms that do not disable as in major depression. However, the symptoms of dysthymia prevent a person from functioning well or from feeling good. Furthermore, people with dysthymia often experience major depressive episodes throughout their lives⁶.

Bipolar disorder is not nearly as prevalent as other types of depression, and it is characterized as a manic-depressive illness. People with bipolar disorder suffer from cycling mood changes: mania (severe highs during which the individual may be overactive and have a great deal of energy) and depression (lows during which the individual has the symptoms of a depressive disorder).

Major depressive disorder is often associated with changes in brain function or brain structures⁷. Some types of depression, including bipolar disorder, run in families, suggesting that hereditary factors may play a role. However, other factors such as stress may also be a factor. Physical changes in the body such as stroke, heart attack, cancer, Parkinson's disease and hormonal disorders may be accompanied by mental changes such as depression. Often, a combination of genetic, psychological and environmental factors is involved in the inception of a depressive disorder⁸.

Depressive disorders are often treated with a combination of antidepressant medications and psychotherapies. Medications include selective serotonin reuptake inhibitors (SSRIs), tricyclics and monoamine oxidate inhibitors (MAOIs). Usually, they must be taken regularly for three to four weeks before the full therapeutic effect occurs. Once the individual feels better, the medication must be taken for at least four to nine months to prevent a recurrence⁹ Treatment is available for people suffering from depressive disorders. The first step is to seek help and obtain an appropriate diagnosis.

Discussion questions

1. Please summarize the article. What is the main point of the article?
2. What is a depressive disorder?
3. How many people suffer from depressive disorders in the U.S.?
4. What are some of the most different types of depressive disorders?
5. What causes depressive disorders?
6. How are depressive disorders treated?

References:

1. What is a depressive disorder? U.S. National Institute of Mental Health. (Accessed 27 September 2007)
2. Depression guide. WebMD. (Accessed 27 September 2007)
3. Older adults: Depression and suicide risk. U.S. National Institute of Mental Health. (Accessed 27 September 2007)
4. Conwell Y. Suicide in later life: a review and recommendations for prevention. Suicide and Life Threatening Behavior, 2001; 31(Suppl): 32-47. [Reference in Older adults: Depression and suicide risk. U.S. National Institute of Mental Health. (Accessed 27 September 2007)]
5. Symptoms of depression and mania. U.S. National Institute of Mental Health. (Accessed 27 September 2007)
6. What is a depressive disorder? U.S. National Institute of Mental Health. (Accessed 27 September 2007)
7. Causes of depression. U.S. National Institute of Mental Health. (Accessed 27 September 2007)
8. Causes of depression. U.S. National Institute of Mental Health. (Accessed 27 September 2007)
9. Causes of depression. U.S. National Institute of Mental Health. (Accessed 27 September 2007)

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