The aim of the present study was to analyze the clinical course and prognosis of bipolar I and II patients with and without CUDs (DSM-IV Cannabis dependence and Cannabis abuse) using the Collaborative Study on the Genetics of Alcoholism (COGA) sample. Subgroups of bipolar individuals with and without comorbid CUDs were compared over a five-year follow-up time period. Subjects were assessed at baseline regarding their lifetime history of SUD, bipolar disorders and then re-interviewed prospectively after 5 years. In these analyses, both bipolar I and II subjects are included to investigate the lifetime characteristics of CUDs, other alcohol and substance dependence and bipolar disorders retrospectively. Secondly, we examined the course of CUDs, other alcohol and substance dependence, BD and comorbidity with mental and other SUD during the 5-year follow-up period. Thirdly, we analysed the moderating effect of CUD on the risk for developing other alcohol and SUDs or the number of comorbid psychiatric illnesses.
