The association between substance abuse and antidepressant-induced mania in bipolar disorder: A preliminary study

Background: Estimates of the prevalence and features of antidepressant-induced mania vary widely, with few data available on its potential risk factors. Method: Fifty-three DSM-IV bipolar patients were interviewed to retrospectively identify lifetime affective episodes, pharmacotherapy trials, and clinical outcomes, with corroboration from treating clinicians and reviews of medical, psychiatric, and pharmacy records. Particular attention was given to the possible relationship between antidepressant-induced mania and the presence of psychoactive substance abuse or dependence. Results: Antidepressant-induced mania or hypomania was evident in 39.6% (21/53) of the study group. Patients who developed manic features soon after starting an antidepressant had more antidepressant trials per year than those who did not (p < .05). A history of substance abuse and/or dependence was associated with substantially increased risk for antidepressant-induced mania (odds ratio = 6.99, 95% CI = 1.57 to 32.28, p = .007). Concomitant mood stabilizers were not uniformly associated with protection against inductions of mania during antidepressant trials. Conclusion: Multiple antidepressant exposures among bipolar patients with histories of substance abuse and/or dependence may be associated with an elevated risk for antidepressant-induced mania.