Dysthymia, also known as persistent depressive disorder (PDD), is a mood disorder characterized by the same mental and physical symptoms as depression but they last longer. Dysthymia is less short-lived and severe than major depressive disorder.
Cyclothymia can occur in childhood and adulthood, and the average age onset of this condition is 31. Globally, dysthymia affects 1.5% of population, although the prevalence in the United States tends to be somewhat higher compared with rates in other countries. Dysthymia is more common in women than in men.
Cyclothymia often coexists with other conditions such as anxiety disorder (up to 50%), personality disorders (up to 40%), somatoform disorders (up to 45%) and substance abuse (up to 50%).