Cultural considerations that were suggested for Major Depressive Episodes are also relevant to Manic Episodes. Manic Episodes in adolescents are more likely to include psychotic features and may be associated with school truancy, antisocial behavior, school failure, or substance use. A significant minority of adolescents appear to have a history of long-standing behavior problems that precede the onset of a frank Manic Episode. It is unclear whether these problems represent a prolonged prodrome to Bipolar Disorder or an independent disorder. See the corresponding sections of the texts for Bipolar I Disorder and Bipolar II Disorder for specific information on gender.
The mean age at onset for a first Manic Episode is the early 20s, but some cases start in adolescence and others start after age 50 years. Manic Episodes typically begin suddenly, with a rapid escalation of symptoms over a few days. Frequently, Manic Episodes occur following psychosocial stressors. The episodes usually last from a few weeks to several months and are briefer and end more abruptly than Major Depressive Episodes. In many instances (50%-60%), a Major Depressive Episode immediately precedes or immediately follows a Manic Episode, with no intervening period of euthymia. If the Manic Episode occurs in the postpartum period, there may be an increased risk for recurrence in subsequent postpartum periods and the specifier With Postpartum Onset is applicable.