The impact of substance abuse on the course of bipolar disorder

Background: Substance abuse occurs at high rates in bipolar disorder. The r easons for this co-occurrence are unknown. Alcohol use disorders have been associated with both earlier and later age of onset of bipolar disorder, in parr based on the temporal associations of the two conditions. Both drug a nd alcohol use disorders are associated with impaired outcome of bipolar il lness. This influence may involve both direct effects of alcohol or drugs o n the initiation of affective symptoms and indirect effects on treatment co mpliance. To extend these previous findings we examined the temporal associ ations of substance abuse and affective symptoms in patients with new onset bipolar disorder. Methods: Associations between affective symptoms and alcohol and cannabis u se disorder symptoms were evaluated using regression and time-series correl ative methods in 50 new-onset bipolar patients. Results: The duration of alcohol abuse during follow-up was associated with the time patients experienced depression. The duration of cannabis abuse w as associated with the duration of mania. Several subgroups could be identi fied with different temporal relationships among these disorders. Conclusions: Although the relationships among substance use and bipolar dis orders are complex, systematic study of the courses of the disorders might clarify how these conditions interact longitudinally. As the numbers of sub jects in specific subgroups are relatively small in this study, these resul ts should be considered preliminary. (C) 2000 Society of Biological Psychia try.