Dysthymia is characterized by depressed mood for most of the day, on more days than not, for at least two years. Additionally, a diagnosis of dysthymia requires the presence of at least two of these symptoms while depressed:
- poor appetite or overeating
- trouble sleeping or sleeping too much
- fatigue, loss of energy or tired all the time
- low self-esteem
- impaired concentration and difficulty making decisions
- feelings of hopelessness and helplessness
To be considered as indicative of dysthymia, the first two years of depressed mood cannot include any episodes of major depression. Furthermore, diagnosis of dysthymia precludes a history of manic episodes and requires that depressed mood occur not during the course of some other psychiatric disorder such as schizophrenia. In addition, no underlying cause of depressed mood, such as a general (i.e., other than psychiatric) medical condition or substance abuse, must be present.
The symptoms of dysthymia cause significant distress or impairment in social, occupational, and other important areas of functioning.