Comparative efficacy of typical and atypical antipsychotics as add-on therapy to mood stabilizers in the treatment of acute mania

Abstract

Background: Typical antipsychotics are commonly used in combination with mood stabilizers for acute mania. Although typical antipsychotics are effective, they have undesirable side effects such as induction of depressive symptoms and tardive dyskinesia. Atypical antipsychotics have more favorable side effect profiles, and recent evidence shows their efficacy in treating mania. Apart from a previous small study that compared risperidone with typical neuroleptics as add-on therapy to mood stabilizers, no studies to date have directly compared atypical antipsychotics with typical antipsychotics as add-on therapy to mood stabilizers in a clinically relevant, naturalistic setting.

Method: This study is a chart review of all patients with DSM-IV-defined bipolar disorder, current episode mania (N = 204), admitted to the University of British Columbia Hospital during a 30-month period. Patients were separated into 3 groups according to the medications used: (1) mood stabilizer and typical antipsychotic, (2) mood stabilizer and atypical antipsychotic, and (3) combination: mood stabilizer plus a typical antipsychotic, then switched to mood stabilizer plus risperidone or olanzapine within I week. The atypical group was further subdivided into risperidone and olanzapine subgroups. Outcome was measured using Clinical Global Impressions-Severity of Illness (CGI-S) and -Improvement (CGI-I) ratings generated by review of clinical information in the chart.

Results: Patients treated with typical antipsychotics were more severely ill at admission and at discharge than those treated with atypical antipsychotics. Patients in the atypical (p < .005) and combination (p < .05) groups showed significantly greater clinical improvement at discharge than patients treated with typical antipsychotics. This difference was also significant in the subset of patients with psychotic features (p < .03). Risperidone and olanzapine were associated with fewer extrapyramidal side effects than were typical antipsychotics (risperidone vs. typical antipsychotics, chi2 = 8.72, p < .01; olanzapine vs. typical antipsychotics, chi2 = 16.9, p < .001).

Conclusion: Due to their superior effectiveness and side effect profile when compared with typical antipsychotics. atypical antipsychotics are an excellent choice as add-on therapy to mood stabilizers for the treatment of patients with mania.