Major depression is a serious medical illness affecting 15 million American adults, or approximately 5-8 percent of the adult population in a given year. Unlike normal emotional experiences of sadness, loss or passing mood states, major depression is persistent and can significantly interfere with an individual's thoughts, behavior, mood, activity and physical health. Among all medical illnesses, major depression is the leading cause of disability in the United States and many other developed countries.
Depression occurs twice as frequently in women as in men, for reasons that are not fully understood. For more please visit NAMI's section for Women and Depression. More than one-half of those who experience a single episode of depression will continue to have episodes that occur as frequently as once or even twice a year. Without treatment, the frequency of depressive illness as well as the severity of symptoms tends to increase over time. Left untreated, depression can lead to suicide.
Major depression, also known as clinical depression or unipolar depression, is only one type of depressive disorder. Other depressive disorders include dysthymia (chronic, less severe depression) and bipolar depression (the depressed phase of bipolar disorder). People who have bipolar disorder experience both depression and mania. Mania involves unusually and persistently elevated mood or irritability, elevated self-esteem and excessive energy, thoughts and talking.
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