Course and outcome of bipolar disorder

Bipolar disorder (BPD) is capricious illness. For some, it is a condition of few episodes; for others, it is unremitting. For some, elevated moods predominate; for others, depression is the major key. For a minority, the condition is predictably cyclical; for most, it is unpredictably chaotic. This chapter examines those studies that have attempted to draw coherence from this enigmatic disorder. Where possible, we will focus on data derived from prospective longitudinal investigations, while using as necessary the more limited retrospective or cross-sectional reports. For the sake of parsimony, we will limit discussion to those studies that have used the conservative historical definitions of BPD (as used in DSM-IIIR, DSM-IV, and ICD-10), eschewing the recent controversial concepts of "pediatric" BPD and "soft BPD spectrum."