Aripiprazole for the management of schizophrenia in the Japanese population: a systematic review and meta- analysis of randomized controlled trials

Background: We conducted a systematic review and meta-analysis of randomized controlled trials comparing aripiprazole with pooled antipsychotics in Japanese patients with schizophrenia. Methods: We performed a literature search of data published in PubMed (R), the Cochrane Library database, the Japan Medical Abstracts Society, and PsycINFO (R) up to January 5, 2014. The odds ratio (OR), number-needed-to-harm (NNH), and standardized mean difference (SMD) based on a random effects model were calculated. Results: We identified five relevant studies (seven comparisons, n=684; one comparison each for haloperidol [n=243], mosapramine [n=238], olanzapine [n=39], quetiapine [n=42], perospirone [n=100], and two comparisons for risperidone [n=66]). There were no significant differences in the Positive and Negative Syndrome Scale (PANSS) total, negative, and general scores (SMD=0.10, SMD=-0.09, SMD=0.10, respectively); discontinuation rate associated with all causes (OR=1.35); or side effects (OR=1.03) between aripiprazole and the pooled antipsychotics. Aripiprazole was inferior to the pooled antipsychotics in PANSS positive subscale scores (SMD=0.17) and discontinuation because of inefficacy (OR=2.21, NNH=11). However, aripiprazole had fewer side effects compared with the pooled antipsychotics (OR=0.21, NNH=20 for one or more side effects), including fatigue (OR=0.22, NNH=8), hyperprolactinemia (OR=0.00, NNH=1), extrapyramidal symptoms (OR=0.46, NNH=6), and weight gain (OR=0.36, NNH=7). Moreover, aripiprazole was associated with lower total cholesterol (SMD=-0.20) and triglyceride (SMD=-0.17) levels and body weight (SMD=-0.20) compared with the pooled antipsychotics. Conclusion: Although the discontinuation rate associated with inefficacy was higher with aripiprazole than with the pooled antipsychotics, aripiprazole was associated with a lower risk of hyperprolactinemia and metabolic and extrapyramidal symptoms compared with the pooled antipsychotics.