- Symptoms of dysthymic disorder (chronic, mild depression) must persist for at least two years in adults (one year in children) to meet criteria for the diagnosis.
- Dysthymic disorder affects approximately 1.5 percent of the U.S. population ages 18 and older in a given year. This figure translates into about 3.3 million American adults.
- The median age of onset of dysthymic disorder is 31.
- Bipolar disorder (also known as manic-depression) affects approximately 5.7 million American adults, or about 2.6 percent of the U.S. population ages 18 and older, in a given year.
- The median age of onset for bipolar disorder is 25.
How Common Is Depression? -- Statistics From 2004
The National Survey on Drug Use and Health (NSDUH) is an annual survey sponsored by the Substance Abuse and Mental Health Services Administration (SAMHSA). Prior to 2002, this survey was called the National Household Survey on Drug Abuse (NHSDA). The 2004 data are based on information obtained from 45,453 people ages 18 and older, 22,825 of whom were asked questions about experiences with depression.
- In 2004, among people ages 18 and older, an estimated 14.8 percent (31.6 million adults) had experienced at least one major depressive episode in their lifetime, and an estimated 8 percent (17.1 million adults) reported having experienced a major depressive episode in the past year.
- Rates of major depression in the past year varied by age group. Adults ages 18 to 25 and those ages 35 to 49 had the highest rates of major depression in the past year (10.1 and 10.4 percent, respectively), and adults ages 65 and older had the lowest rate (1.3 percent).
- Females (10.3 percent) were almost twice as likely as males (5.6 percent) to report major depression during the past year.
- Rates of major depression during the past year varied by annual family income. Adults from households with a family income of less than $20,000 experienced the highest rate of major depression (11 percent). Adults from households with a family income of $50,000 or more had the lowest rate of major depression (7 percent). Among adults from households with a family income of $20,000 to $49,999, 7.6 percent had major depression.
- Rates of major depression were similar in large metropolitan areas (7.8 percent), small metropolitan areas (8.3 percent), and non-metropolitan areas (8.3 percent).