Improvement in cognitive function following a switch to ziprasidone from conventional antipsychotics, olanzapine, or risperidone in outpatients with schizophrenia

Philip D. Harvey, Herbert Meltzer, George M. Simpson, Steven G. Potkin, Antony Loebel, Cynthia Siu, Steven J. Romano

Research output: Contribution to journalArticle

87 Scopus citations


Objective: To assess changes in cognitive function in stable outpatients with schizophrenia switched to ziprasidone from conventional antipsychotics (n=108), olanzapine (n=104), or risperidone (n=58) because of suboptimal efficacy or poor tolerability. Methods: In three separate 6-week trials, patients received ziprasidone 40 mg b.i.d. for 2 days, followed by 20-80 mg b.i.d. for the next 40 days. Before switching, and at endpoint, patients were evaluated with tests of working and secondary verbal memory, vigilance, visuomotor speed, verbal fluency, and executive functioning. Principal components factor analysis was performed to test for clustering of cognitive variables. Results: Significant improvements were seen at endpoint in secondary verbal memory (in all three groups), vigilance (in patients switched from conventional antipsychotics or risperidone), executive function (in patients switched from conventional antipsychotics or risperidone), and verbal fluency. Factor analysis on baseline scores suggested reduction of the cognitive variables to three factors: verbal skills, attention and short-term memory, and executive functioning. Analysis of z-transformed mean change in factor scores showed significant improvement in verbal skills and global score following the switch from conventional antipsychotics, olanzapine, or risperidone. Conclusions: Patients requiring a change in antipsychotic therapy may exhibit cognitive improvement following a switch to ziprasidone.

Original languageEnglish (US)
Pages (from-to)101-113
Number of pages13
JournalSchizophrenia Research
Issue number2-3
StatePublished - Feb 1 2004



  • Attention
  • Atypical antipsychotics
  • Cognition
  • Executive functioning
  • Schizophrenia
  • Verbal fluency
  • Vigilance
  • Ziprasidone

ASJC Scopus subject areas

  • Psychiatry and Mental health
  • Behavioral Neuroscience
  • Biological Psychiatry
  • Neurology
  • Psychology(all)

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