Aim: To evaluate the efficacy of olanzapine in patients in their manic/mixed phase with or without comorbidity with substance abuse/dependence disorder.
Methods: In this observational, controlled, prospective study, 60 patients with a DSM-IV-TR diagnosis of bipolar disorder, manic/mixed episode (30 patients with and 30 patient without comorbidity with a substance abuse/dependence disorder) were treated with olanzapine, evaluated at discharge, and followed-up for 8 weeks. Efficacy of olanzapine was assessed by comparing the proportion of responders (an at least 50% drop in Young Mania Rating Scale [YMRS] score from baseline) and remitters (YMRS ≤ 12 and Hamilton Depression Rating Scale [HAM-D] ≤ 8) in both groups. Craving and days of abuse/use were assessed with Visual Analogue Scale (VAS) and Time-line Follow-Back (TLFB), respectively.
Results: Differences in response and remission percentages were statistically not significant at discharge and during follow-up. A reduction of days of abuse has been observed in the drug-abuse group, while craving was only slightly decreased.
Discussion: These results suggest that olanzapine is effective in both groups and its efficacy in reducing the days of abuse appears to be independent from its action on craving.