In children, Dysthymic Disorder seems to occur equally in both sexes and often results in impaired school performance and social interaction. Children and adolescents with Dysthymic Disorder are usually irritable and cranky as well as depressed. They have low self-esteem and poor social skills and are pessimistic. In adulthood, women are two to three times more likely to develop Dysthymic Disorder than are men.
The lifetime prevalence of Dysthymic Disorder (with or without superimposed Major Depressive Disorder) is approximately 6%. The point prevalence of Dysthymic Disorder is approximately 3%.
Dysthymic Disorder often has an early and insidious onset (i.e., in childhood, adolescence, or early adult life) as well as a chronic course. In clinical settings, individuals with Dysthymic Disorder usually have superimposed Major Depressive Disorder, which is often the reason for seeking treatment. If Dysthymic Disorder precedes the onset of Major Depressive Disorder, there is less likelihood that there will be spontaneous full interepisode recovery between Major Depressive Episodes and a greater likelihood of having more frequent subsequent episodes. Although the spontaneous remission rate for Dysthymic Disorder may be as low as 10% per year, evidence suggests the outcome is significantly better with active treatment. The treated course of Dysthymic Disorder appears similar to that of other Depressive Disorders, whether or not there is a superimposed Major Depressive Disorder.
Dysthymic Disorder is more common among first-degree biological relatives of people with Major Depressive Disorder than among the general population. In addition, both Dysthymic Disorder and Major Depressive Disorder are more common in the first-degree relatives of individuals with Dysthymic Disorder.