Effects of quetiapine on cognitive functions in schizophrenia

Objective: All atypical antipsychotic drugs with complex pharmacology have been shown to improve some, but not all, domains of cognitive function, including quetiapine, i.e., the agent with the most rapid dissociation from dopamine receptors and a relatively weak serotonin antagonism. The present study was to evaluate which, if any, areas of cognition improve in patients with schizophrenia, following a brief treatment with quetiapine. Methods: Effects of quetiapine on cognition were investigated in a group of patients with schizophrenia (n = 14). Neuropsychological tests in cognitive areas previously shown as impaired in schizophrenia were administered at baseline and after 8 weeks of treatment with quetiapine. Administered at these two times were also the Positive and Negative Syndrome Scale, Hamilton Depression Rating Scale, and scales to assess motor side effects (Abnormal Involuntary Movement Scale, Simpson-Angus Scale, and Barnes Akathisia Scale). Results: Wilcoxon Signed Ranks Test indicated a statistically significant improvement in scores on Digit Span Test, Trail Making Test, Stroop Test, Finger Tapping Test, and on the Positive and Negative Syndrome Scale. No significant change was noted in motor side effects. Conclusion: The patients improved in their attentional, motor, and visuo-motor skills, and in executive functions as well as with respect to psychopathology, without an increase in motor side effects. (C) 2004 Elsevier Inc. All rights reserved.