title: Neurocognitive effects of clozapine, olanzapine, risperidone, and haloperidol in patients with chronic schizophrenia or schizoaffective disorder.
abstract: OBJECTIVE
  Newer antipsychotic drugs have shown promise in ameliorating neurocognitive deficits in patients with schizophrenia, but few studies have compared newer antipsychotic drugs with both clozapine and conventional agents, particularly in patients who have had suboptimal response to prior treatments.
  
  
  METHODS
  The authors examined the effects of clozapine, olanzapine, risperidone, and haloperidol on 16 measures of neurocognitive functioning in a double-blind, 14-week trial involving 101 patients. A global score was computed along with scores in four neurocognitive domains: memory, attention, motor function, and general executive and perceptual organization.
  
  
  RESULTS
  Global neurocognitive function improved with olanzapine and risperidone treatment, and these improvements were superior to those seen with haloperidol. Patients treated with olanzapine exhibited improvement in the general and attention domains but not more than that observed with other treatments. Patients treated with risperidone exhibited improvement in memory that was superior to that of both clozapine and haloperidol. Clozapine yielded improvement in motor function but not more than in other groups. Average effect sizes for change were in the small to medium range. More than half of the patients treated with olanzapine and risperidone experienced "clinically significant" improvement (changes in score of at least one-half standard deviation relative to baseline). These findings did not appear to be mediated by changes in symptoms, side effects, or blood levels of medications.
  
  
  CONCLUSIONS
  Patients with a history of suboptimal response to conventional treatments may show cognitive benefits from newer antipsychotic drugs, and there may be differences between atypical antipsychotic drugs in their patterns of cognitive effects.
authors.affiliation: Nathan S. Kline Institute for Psychiatric Research, Orangeburg, NY 10962, USA. bilder@nki.rfmh.org
authors.forename: Robert M
authors.initials: RM
authors.lastname: Bilder
authors.forename: Robert S
authors.initials: RS
authors.lastname: Goldman
authors.forename: Jan
authors.initials: J
authors.lastname: Volavka
authors.forename: Pal
authors.initials: P
authors.lastname: Czobor
authors.forename: Matthew
authors.initials: M
authors.lastname: Hoptman
authors.forename: Brian
authors.initials: B
authors.lastname: Sheitman
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Lindenmayer
authors.forename: Leslie
authors.initials: L
authors.lastname: Citrome
authors.forename: Joseph
authors.initials: J
authors.lastname: McEvoy
authors.forename: Michal
authors.initials: M
authors.lastname: Kunz
authors.forename: Miranda
authors.initials: M
authors.lastname: Chakos
authors.forename: Thomas B
authors.initials: TB
authors.lastname: Cooper
authors.forename: Terri L
authors.initials: TL
authors.lastname: Horowitz
authors.forename: Jeffrey A
authors.initials: JA
authors.lastname: Lieberman
mesh_terms: D000328:Adult; D014150:Antipsychotic Agents / Q000627:therapeutic use*; D001569:Benzodiazepines; D003024:Clozapine / Q000627:therapeutic use; D003071:Cognition / Q000187:drug effects*; D004311:Double-Blind Method; D005260:Female; D006220:Haloperidol / Q000627:therapeutic use; D006801:Humans; D008297:Male; D009483:Neuropsychological Tests / Q000706:statistics & numerical data*; D000077152:Olanzapine; D010890:Pirenzepine / Q000031:analogs & derivatives* / Q000627:therapeutic use; D011618:Psychotic Disorders / Q000188:drug therapy*; D018967:Risperidone / Q000627:therapeutic use; D012559:Schizophrenia / Q000188:drug therapy; D012565:Schizophrenic Psychology; D016896:Treatment Outcome
chemical_list: D014150:Antipsychotic Agents; D001569:Benzodiazepines; D010890:Pirenzepine; D003024:Clozapine; D006220:Haloperidol; D018967:Risperidone; D000077152:Olanzapine