Dysthymia is similar to major depression in that it involves feelings of sadness and depression. However, these feelings of sadness and depression are typically not as intense as in major depressive disorder and are more long-lasting. People with dysthymia report feeling down or blue more days than not for two years or more. In fact, it is possible for someone to suffer from dysthymia for 20 or 30 years or more. Besides chronic, low-level feelings of sadness, other symptoms of dysthymia may include: changes in appetite, sleep problems, fatigue, low self-esteem, poor concentration, and feelings of hopelessness or pessimism about the future.
In any given year, approximately 1.6% of the population experiences dysthymia (best estimate by the surgeon general based on the Epidemiological Catchment Area study and the National Comorbidity Survey).