Change of Cognitive Functions in Switching of Risperidone for Chronic Schizophrenic Patients

Hong, Hyun Ju; Chung, Hae Gyung; Choi, Jin Hee; Choi, Young An

Abstract

OBJECTIVE
The aim of this study is to evaluate the effect of risperidone on cognitive functions in chronic schizophrenic patients after 8 weeks of treatments and determine whether any improvement on cognitive function relates to improvement in psychopathology. METHODS: The subjects were 20 chronic schizophrenic outpatients, who participated in eight-week crossover study from conventional antipsychotics to risperidone. Clinical symptoms were assessed by Positive and Negative Syndrome Scale, Clinical Global Impression and Extrapyramidal Symptom Rating Scale, while they were receiving conventional antipsychotic treatment. Cognitive functions were assessed by K-WAIS digit span and digit symbol substitution test, and vigilance, continuous attention, reaction unit, corsi-block-tapping test. Patients were then reassessed after changing to a new treatment of risperidone. RESULTS: After crossover from conventional antipsychotics to risperidone, positive and negative symptoms and the general psychopathology were significantly improved. The only item of Vienna tests significantly improved after risperidone treatment was corsi-block-tapping test. However, this improvement was not related to the improvement in psychopathology. Backward digit span score, digit span total score, digit symbol substitution score were significantly improved after risperidone treatment. But this improvement was not related to the improvement in psychopathology, except digit span total score. Digit span total score was related to the improvement in negative symptom score and PANNS total score. CONCLUSION: Treatment with risperidone appeared to exert a favorable effect on visuospatial memory and working memory, but long-term and larger sample replication study is necessary.