Time to psychiatric hospitalization in patients with bipolar disorder treated with a mood stabilizer and adjunctive atypical antipsychotics: a retrospective claims database analysis.

OBJECTIVE: This study compared the time to psychiatric hospitalization in commercially insured patients with bipolar disorder who were treated with a mood stabilizer plus adjunctive aripiprazole versus adjunctive ziprasidone, olanzapine, quetiapine, or risperidone.

METHODS: This was a retrospective, propensity score-matched cohort study using the Ingenix I3/LabRx integrated insurance claims data set. Patients with bipolar disorder were included if they had >or=180 days of pre-index enrollment in the health plan without atypical antipsychotic exposure. Patients received mood stabilizers and subsequently received adjunctive atypical antipsychotic agents; they were then monitored for up to 90 days after the index antipsychotic prescription. The primary analysis was a Cox proportional hazards analysis to evaluate the time until psychiatric hospitalization comparing adjunctive aripiprazole with ziprasidone, olanzapine, quetiapine, or risperidone after adjusting for age, sex, and preindex hospitalization.

RESULTS: Adjunctive aripiprazole was associated with a longer time until hospitalization than adjunctive ziprasidone, olanzapine, quetiapine, or risperidone (hazard ratios 1.7, 1.6, 1.5, and 1.5, respectively; all, P < 0.05). Mean initial and maximum doses of all drugs were below those recommended by the package insert or clinical practice guidelines. Sensitivity analyses suggested the robustness of the results in the general population of patients with bipolar disorder recently treated with atypical antipsychotics.

CONCLUSIONS: This retrospective claims-data analysis suggests that in these adults with bipolar disorder treated with mood stabilizers, the addition of adjunctive aripiprazole was associated with a longer time to hospitalization than adjunctive ziprasidone, olanzapine, quetiapine, or risperidone during a 90-day follow-up period.