title: Efficacy of quetiapine in patients with bipolar I and II depression: a multicenter, prospective, open-label, observational study.
abstract: OBJECTIVE
  To evaluate and compare the therapeutic efficacy of quetiapine in bipolar I and II depression patients in the clinical setting.
  
  
  METHODS
  This was an 8-week, multicenter, open-label, observational study for bipolar depression. The dosage of quetiapine was flexible, and concomitant medications were permitted on clinician's judgments. A total of 1097 patients were enrolled, and 764 bipolar depression patients who exhibited good therapeutic compliance (>75% compliance rate) were analyzed.
  
  
  RESULTS
  Clinical Global Impression - Bipolar scale and Montgomery-Asberg Depression Rating Scale scores were significantly improved at weeks four and eight compared with the baseline scores. At the end of the 8-week study, the response rate was 58.9%, and the remission rate was 42.1%. However, there were no significant differences in the response and remission rates between bipolar I and II disorder (BD-I and BD-II) patients (response rate 60.1% versus 56.3%; remission rate 44.5% versus 37.0%). Montgomery-Asberg Depression Rating Scale score at baseline (β = 0.612, P < 0.001), duration of current episode (β = -0.152, P = 0.001), and presence of remission on previous episode (β = 0.111, P = 0.012) were significantly associated with improvements in depressive symptoms. Fatigue (16.0%), somnolence (14.9%), and manic/hypomanic switching (0.6% at week four, 0.3% at week eight) were observed throughout the study period.
  
  
  CONCLUSIONS
  The results of this study suggest that quetiapine improves depressive symptoms in BD-I and BD-II patients with a minimal incidence of manic switching. The therapeutic efficacy of quetiapine increased with time. Quetiapine could be an effective and safe modality for the treatment of BD-I and BD-II.
authors: Department of Psychiatry, College of Medicine, The Catholic University of Korea, Seoul.
authors: Jong-Hyun
authors: JH
authors: Jeong
authors: Won-Myong
authors: WM
authors: Bahk
authors: Young Sup
authors: YS
authors: Woo
authors: Ho-Jun
authors: HJ
authors: Seo
authors: Seung-Chul
authors: SC
authors: Hong
authors: Duk-In
authors: DI
authors: Jon
authors: Kyung Joon
authors: KJ
authors: Min
authors: Bo-Hyun
authors: BH
authors: Yoon
keywords: bipolar depression; observational study; quetiapine; therapeutic efficacy