Does the manic/mixed episode distinction in bipolar disorder patients run true over time?

Abstract

The authors sought to determine whether the manic/mixed episode distinction in patients with bipolar disorder runs true over time. Over an 11-year period, the observed distribution of manic and mixed episodes (N=1,224) for patients with three or more entries in the management information system of a community mental health center (N=241) was compared to the expected distribution determined by averaging 1,000 randomly generated simulations. Episodes were consistent (all manic or all mixed) in significantly more patients than would be expected by chance. These data suggest a pattern of diagnostic stability over time for manic and mixed episodes in patients with bipolar disorder. Careful prospective studies of this issue are needed.