Phenomenology of Rapid-Cycling Bipolar Disorder: Data From the First 500 Participants in the Systematic Treatment Enhancement Program

OBJECTIVE: This study compared demographic and phenomenological variables between bipolar patients with and without rapid cycling as a function of bipolar I versus bipolar II status. METHOD: The authors examined demographic, historical, and symptomatic features of patients with and without rapid cycling in a cross-sectional study of the first 500 patients with bipolar I or bipolar II disorder enrolled in the Systematic Treatment Enhancement Program for Bipolar Disorder, a multicenter project funded by the National Institute of Mental Health designed to evaluate the longitudinal outcome of patients with bipolar disorder. RESULTS: Rapid-cycling bipolar disorder occurred in 20% of the study group. Rapid-cycling patients were more likely to be women, although the effect was somewhat more pronounced among bipolar I patients than bipolar II patients. In addition, rapid-cycling bipolar patients experienced onset of their illness at a younger age, were more often depressed at study entry, and had poorer global fu...