An Unblinded Comparison of the Clinical and Cognitive Effects of Switching from First-generation Antipsychotics to Aripiprazole, Perospirone or Olanzapine in Patients with Chronic Schizophrenia

The objective of this study, the effect of aripiprazole on clinical symptoms and cognitive function in patients with chronic schizophrenia was compared to that of perospirone and olanzapine. The subjects were 31 patients, they were diagnosed with schizophrenia on the basis of the criteria of the DSM-IV. Clinical symptoms were assessed using Brief Psychiatric Rating Scale (BPRS), and cognitive function was assessed using the Wisconsin Card Sorting Test (Keio Version: KWCST) and the St. Marianna University School of Medicine's Computerized Memory Test (STM-COMET) as executive function and memory/attention function tests at baseline and 8 weeks after switching. As a result, comparison of the BPRS mean total score revealed no significant difference between aripiprazole and the other medications. Aripiprazole resulted in significant changes in the number of categories achieved (CA) and difficulty maintaining set (DMS) compared to olanzapine at the second level of the KWCST. Comparison thus revealed no difference in clinical effect between aripiprazole and the other medications, but might suggest possible differences between aripiprazole and olanzapine in the profiles of the improvement effects on executive function, memory, and attention function.