Insulin resistance induced by olanzapine and other second-generation antipsychotics in Chinese patients with schizophrenia: a comparative review and meta-analysis.

Purpose: This systematic review aimed to determine whether olanzapine is more likely than other second-generation antipsychotics (SGAs) to induce insulin resistance in patients with schizophrenia in China.

Methods: We reviewed all randomized controlled trials on insulin resistance and metabolic abnormalities caused by SGAs in the PubMed, China National Knowledge Infrastructure (CNKI), VIP, and Wanfang databases. Retrieved articles were published on or before December 2018. Meta-analysis was performed to determine the effect size of the treatment on the insulin resistance index (IRI), fasting blood glucose (FBG), and fasting insulin (FINS).

Results: Forty studies (3725 participants in total) were included. All studies contained data suitable for comparing aripiprazole vs. olanzapine, ziprasidone vs. olanzapine, and risperidone vs. olanzapine. Patients treated with olanzapine had higher IRI, FBG, and FINS levels than did patients treated with aripiprazole, ziprasidone, or risperidone, with significant differences (aripiprazole vs. olanzapine: FBG: standardized mean difference [SMD] = 0.72, 95% confidence interval [95%CI] - 0.82, - 0.61; FINS: SMD = - 0.8, 95%CI - 1.00, - 0.61; IRI: SMD = - 0.80, 95%CI - 0.99, - 0.61; ziprasidone vs. olanzapine: FBG: SMD = - 1.19, 95%CI - 1.30, - 1.08; FINS: SMD = - 0.66, 95%CI - 0.85, - 0.47; IRI: SMD = - 0.71, 95%CI - 0.88, - 0.55; risperidone vs. olanzapine: FBG: SMD = - 0.17, 95%CI - 0.34, - 0.00).

Conclusions: Existing data suggest that olanzapine is associated with a significantly greater risk of IRI, FBG, and FINS, while other agents are associated with relatively lower risks. Thus, olanzapine is more likely to induce insulin resistance than are other SGAs in schizophrenic patients in China.