Objective: Ziprasidone may improve cognition in schizophrenia; however, this could be related to clinical symptom improvement, reflecting "pseudospecificity". We tested the hypothesis that ziprasidone improves cognition in the absence of clinical improvement.
Methods: We conducted a 12-week, open-label study of ziprasidone in 10 schizophrenia patients who met non-response criteria (<20% reduction in BPRS scores over 12 weeks). We conducted comprehensive cognitive testing and assessed change from baseline to end of study.
Results: We detected significant improvement on three measures of episodic memory (p<0.01) in these clinically non-responsive patients. Trend-level improvements were noted on tests involving processing speed and executive function.
Conclusions: These data suggest that ziprasidone has cognitive benefits unrelated to an influence on other disease parameters.