title: Early prediction of clinical and functional outcome in schizophrenia.
abstract: The objective of this paper was to investigate the prognostic and predictive value of a small panel of independent and clinically important factors based on symptom improvement, baseline cognitive impairment, and weight change during the early treatment phase.
  
  
  METHODS
  The study sample was based on a double-blind, 6-month continuation study of ziprasidone and olanzapine (N=94). We developed a parsimonious 6-month GAF prediction function using a logistic regression model, and evaluated its predictive accuracy and performance using bootstrap estimates of c-statistics and error in predicted probability.
  
  
  RESULTS
  At up to 6 months of follow-up, 52 (55%) of all subjects treated with ziprasidone or olanzapine met the responder criterion of ≥50% improvement in GAF. At Week 2 (acute phase), the majority of ziprasidone (75%) and olanzapine (70%) patients showed greater than 25% improvement in the BPRS psychotic symptom subscale score. These early psychotic symptom responders (Week 2) showed significantly greater improvement in global functioning than early non-responders at all time points (Week 6 and Month 6) (all p's<0.05), confirming early response as an indicator of continued responsiveness to treatment over at least 6 months. A multivariate prediction function based on baseline neurocognitive scores and GAF, early reduction of psychotic symptoms at 2 weeks, and percentage of weight change observed at 6 weeks (All p's <0.05), showed statistically acceptable predictive performance (boostrap c-statistics=0.8598).
  
  
  CONCLUSIONS
  Our findings suggest that a parsimonious model incorporating a psychotic symptom assessment score, baseline neurocognitive performance, and risk of weight gain can be developed for predicting patients' likelihood of achieving favorable, long-term treatment outcomes.
authors.affiliation: Schizophrenia Program, Center for Addiction and Mental Health, Department of Psychiatry, University of Toronto, Toronto, Canada. Ofer_agid@camh.net
authors.forename: Ofer
authors.initials: O
authors.lastname: Agid
authors.forename: Cynthia O
authors.initials: CO
authors.lastname: Siu
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Pappadopulos
authors.forename: Douglas
authors.initials: D
authors.lastname: Vanderburg
authors.forename: Gary
authors.initials: G
authors.lastname: Remington
mesh_terms: D000328:Adult; D014150:Antipsychotic Agents / Q000009:adverse effects / Q000627:therapeutic use*; D001569:Benzodiazepines / Q000009:adverse effects / Q000627:therapeutic use; D003071:Cognition / Q000187:drug effects; D003072:Cognition Disorders / Q000209:etiology / Q000517:prevention & control; D004311:Double-Blind Method; D016903:Drug Monitoring; D004351:Drug Resistance; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D008954:Models, Biological; D000077152:Olanzapine; D010352:Patient Dropouts; D010879:Piperazines / Q000009:adverse effects / Q000627:therapeutic use; D011379:Prognosis; D011569:Psychiatric Status Rating Scales; D012559:Schizophrenia / Q000175:diagnosis / Q000188:drug therapy* / Q000503:physiopathology; D013844:Thiazoles / Q000009:adverse effects / Q000627:therapeutic use; D015430:Weight Gain / Q000187:drug effects
chemical_list: D014150:Antipsychotic Agents; D010879:Piperazines; D013844:Thiazoles; D001569:Benzodiazepines; C092292:ziprasidone; D000077152:Olanzapine
keywords: Benefit–risk profile; Cognitive impairment; Early psychotic response; Global functioning; Predictive function; Weight gain