Lifetime prevalence of substance or alcohol abuse and dependence among subjects with bipolar I and II disorders in a voluntary registry

Objective: To evaluate the prevalence of substance abuse dependence and/or alcohol abuse dependence among subjects with bipolar I versus bipolar II di sorder in a voluntary registry. Method: One hundred randomly selected registrants in a voluntary case regis try for bipolar disorder were interviewed, using the Structured Clinical In terview for DSM-IV Axis I Disorders, to validate the diagnosis of this regi stry. Corroborative information was obtained from medical records, family m embers and the treating psychiatrist. Eighty-nine adults (18-65 years) met criteria for bipolar disorder (bipolar I = 71, bipolar II = 18) and were in cluded in this analysis. Results: Forty-one (57.8%) subjects with bipolar I disorder abused, or were dependent on one or more substances or alcohol. 28.2% abused, or were depe ndent on, two substances or alcohol, and 11.3% abused or were dependent on three or more substances or alcohol. Nearly 39% of bipolar II subjects abus ed or were dependent on one or more substances, nearly 17% were dependent o n two or more substances or alcohol, and 11% were dependent on three or mor e substances or alcohol. Alcohol was the most commonly abused drug among ei ther bipolar I or II subjects. Conclusions: Consistent with other epidemiologic and hospital population st udies, this voluntary bipolar disorder registry suggests a high prevalence of comorbidity with alcohol and/or substance abuse dependence, Bipolar I su bjects appear to have higher rates of these comorbid conditions than bipola r II subjects, however, as the number of bipolar II subjects was rather sma ll, this suggestion needs confirmation.