Comparison of Efficacy and Safety between Risperidone and Quetiapine in Schizophrenia and Schizoaffective Disorder: A Pilot Study

Cho, Seong Jin; Hahm, Bong Jin; Suh, Tong Woo

Abstract

OBJECTIVE
The few direct comparative studies of efficacy and tolerability of atypical antipsychotics have been done in patients commonly seen in clinical practice. We therefore compared, head-to-head, the relative efficacy and tolerability of two atypical antipsychotics, risperidone and quetiapine, commonly used in clinical practice nowadays. METHODS: This study used retrospective chart reviews of the patients who had been admitted to or treated at the outpatient department in a university hospital. The analysed population consisted of 55 patients with diagnoses of schizophrenia or schizoaffective disorder. RESULTS: Among the baseline characteristics, the proportion of patients with a history of previous antipsychotics medication was higher in the quetiapine group, as was the proportion of patients treated at the outpatient department, the proportion of female patients, and the mean age. Even though these baseline differences had been controlled as covariate, the proportion of responsive patients was higher, and the median value of the time to efficacy was shorter, in the risperidone group. The rate of sedation was higher in the quetiapine group and the rates of concomitant use of anticholinergics and benzodiazepines were higher in the risperidone group. However, these differences of sedation and concomitant use of anticholinergics and benzodiazepines were not statistically significant when controlling for the effect of baseline characteristics. Even though this study showed some useful results, the study limitations included the use of retrospective chart reviews and the small number of subjects at a single hospital, among others. Therefore, further studies controlling these limitations need to be done to confirm the results of this study. CONCLUSION: The proportion of responsive patients was higher and the median value of the time to efficacy was shorter in the risperidone group. The rates of extrapyramidal symptoms were not different between the two groups.