Clozapine Versus Other Antipsychotics for Insomnia in Schizophrenia

According to a meta-analysis study, insomnia is a frequent comorbidity in schizophrenia and is associated with increased risk of suicide. The study’s authors evaluated 8 randomized controlled trials to determine if clozapine reduced the incidence of insomnia compared with other antipsychotics in patients with schizophrenia.

Lead author of the study, Brian Miller, stated that clozapine was associated with significantly less insomnia compared to treatment with other antipsychotics among patients with schizophrenia. The data were published in Schizophrenia Research.

Clozapine Reduces Insomnia in Schizophrenia Compared to Other Agents

The analysts identified 8 trials published in English to the PubMed, PsycINFO, and Web of Science databases that reported on insomnia in patients with schizophrenia undergoing treatment with clozapine compared with other antipsychotics. Researchers used a random-effects model to compare outcomes.

The pooled cohort included 1952 patients, of which 922 were on clozapine and 1030 were on other drugs. According to Miller and colleagues, the incidence of insomnia in clozapine patients was 12.4% compared with 22.3% in other antipsychotics patients (odds ratio [OR], 2.20; 95% CI, 1.64-2.94; P<.01). Specifically, the report noted olanzapine, quetiapine, risperidone, and ziprasidone were all associated with statistically significant increased rates of insomnia compared with clozapine.

Authors stated age showed a significant correlation with this association in their meta-regression analysis, whereas clozapine dose, publication year, sex, trial duration, and study quality score did not.

“Clozapine is associated with significantly less insomnia compared to other antipsychotics,” the authors summarized. They suggested their “findings provide additional evidence for improvement in sleep as a potential pathway underlying clozapine’s anti-suicidal properties.”

Related: Impact of Psychotropic Schizophrenia Treatments on Agitation