Quetiapine for the continuation treatment of bipolar depression: naturalistic prospective case series from the Stanley Bipolar Treatment Network.

Continuation treatment for bipolar disorder often consists of a mood stabilizer and a second-generation antipsychotic. Quetiapine has been shown to be an effective treatment for acute mania and acute bipolar depression, but there are limited data for its use in continuation treatment. This study examined the effectiveness of open-label adjunctive quetiapine therapy for continuation treatment in patients with bipolar disorder. Prospectively collected life chart data from 63 outpatients with bipolar disorders, most recent episodes depressed, manic, or cycling, who received adjunctive quetiapine therapy as part of standard acute treatment were analyzed. Patients had 4 or more weeks of prequetiapine baseline data and at least 2 weeks of quetiapine treatment with no other medication changes. Patients were grouped by baseline symptoms; depression only, mania only, or both mania and depression (cycling group). Owing to small mania and well groups (n=4), differences between depression and cycling groups were examined and mania and well groups excluded. Fifty-five patients were included in the analyses. The primary outcome measure was change in mood severity from baseline to change in treatment regimen, as measured by the NIMH Life Charting Method. Patients received adjunctive quetiapine for a mean of 122 (SD=149) days. Both groups showed significant improvement in depression ratings and time spent depressed by week 10. Both groups showed significant improvement in overall mood. No between-group differences in improvement were found. Adjunctive quetiapine may be useful as continuation treatment in bipolar populations with both pure depressive and cycling symptoms. Further controlled studies are warranted.