http://tech.mit.edu/V120/N3/dep1.3n.html
Depression Most Prevalent Mental Disorder in America
By Karyn Lu
This article is the first in a series regarding depression and mental health issues. It presents a general description of depression and its symptoms; future articles will discuss topics such as mental health and support services at MIT.
Clinical depression is far more menacing than just the passing “blues” that everyone experiences at some time or another in their lives. Depression is not a sign of personal weakness, and people suffering from depression cannot simply “pull themselves together.”
In actuality, depression is the most common serious brain disease in the U.S. today. Major (also called unipolar) depression, a physical illness whose principal manifestations are psychological, involves frequent episodes of intense hopelessness and lowered self-esteem. It can effect an individual's mood, body, behavior, and mind; when left untreated, depression may eventually lead to suicide.
Major depression is recognized as the most prevalent type of mood disorder today. It is estimated that 17 percent of the U.S. population (between 5-12 percent of men and 10-20 percent of women) will suffer from a major depressive episode at least once in their lifetime.
According to the DSM-IV (Diagnostic and Statistical Manual of Mental Disorders) of the American Psychiatric Association, the most widely accepted guide for classifying psychiatric and psychological disorders today, a major depressive episode is diagnosed by the presence of at least five of these nine symptoms during the same two-week period:
1. Depressed mood
2. Reduced interest in almost all
activities
3. Unintended significant weight gain or weight loss
4. Insomnia, or sleeping too much
5. Increased or decreased motor activity
6. Fatigue or loss of energy
7. Feelings of worthlessness or guilt
8. Reduced ability to concentrate or think
9. Recurrent thoughts of death