title: Antipsychotic effects of quetiapine in naturalistic long term follow up study.
abstract: OBJECTIVE
  This study aimed to examine the effectiveness of quetiapine and the effects of dosage relates to its effectiveness on schizophrenia and schizoaffective disorder in a naturalistic setting in Korean people.
  
  
  METHODS
  This study was a 24-week, open-label, non-comparative, naturalistic study of quetiapine in patients diagnosed with schizophrenia and schizoaffective disorder according to DSM-IV. We stratified the patients into mild [(clinical global impression severity (CGI-S) <4 at baseline)] and severe groups (CGI-S >/=4 at baseline). We investigated the response rate, defined as clinical global impression improvement (CGI-I) </=2, in the severe group and the aggravation rate in the mild group using the last-observation-carried-forward (LOCF) and the Kaplan-Meier method (K-M).
  
  
  RESULTS
  During the 24 weeks, 151 (18.4%) of the participants dropped out of the study. There was a significant decrease in the mean CGI-S score, from 4.5+/-1.1 at baseline to 2.8+/-1.1 at 24 weeks. The response rate of severe group was 54.5% (estimated by LOCF) and 73.3% (K-M estimated) at 24 weeks. All patients who completed the study had taken a mean quetiapine dosage of 507.9+/-245.9 mg daily. The decrease of CGI-S score in high-dose group (the maximum dose was 750 mg/d or above) was statistically significant than that in recommended-dose group (the maximum dose was less than 750 mg/d).
  
  
  CONCLUSIONS
  This study demonstrated the long-term effectiveness of quetiapine in the treatment of schizophrenia and schizoaffective disorder in a naturalistic setting in Korean people. This study suggests that higher than recommended quetiapine dosages could be more effective in some patients.
authors.affiliation: Department of Psychiatry, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Jung-Sun
authors.initials: JS
authors.lastname: Lee
authors.forename: Joon Ho
authors.initials: JH
authors.lastname: Ahn
authors.forename: Do-Hoon
authors.initials: DH
authors.lastname: Kim
authors.forename: Jong-Jin
authors.initials: JJ
authors.lastname: Kim
authors.forename: Tae-Young
authors.initials: TY
authors.lastname: Kim
authors.forename: So-Young
authors.initials: SY
authors.lastname: Yoo
authors.forename: Dong-Geun
authors.initials: DG
authors.lastname: Lee
authors.forename: Sang-Hyuk
authors.initials: SH
authors.lastname: Lee
authors.forename: Se-Won
authors.initials: SW
authors.lastname: Lim
authors.forename: Weon-Jeong
authors.initials: WJ
authors.lastname: Lim
authors.forename: Il-Kyung
authors.initials: IK
authors.lastname: Jung
authors.forename: Hae-Kyung
authors.initials: HK
authors.lastname: Jung
authors.forename: Dong-Hwan
authors.initials: DH
authors.lastname: Cho
authors.forename: In-Hee
authors.initials: IH
authors.lastname: Cho
authors.forename: Chang-Yoon
authors.initials: CY
authors.lastname: Kim