The prevalence of agranulocytosis and related death in clozapine-treated patients: a comprehensive meta-analysis of observational studies

Abstract

AbstractBackgroundClozapine treatment increases the risk of agranulocytosis, but findings on the epidemiology of agranulocytosis have been inconsistent. This meta-analysis examined the prevalence of agranulocytosis and related death in clozapine-treated patients.MethodsA literature search in the international (PubMed, PsycINFO, and EMBASE) and Chinese (WanFang, Chinese National Knowledge Infrastructure, and Sinomed) databases was conducted. Prevalence estimates of agranulocytosis and related death in clozapine-treated patients were synthesized with the Comprehensive Meta-Analysis program using the random-effects model.ResultsThirty-six studies with 260 948 clozapine-treated patients published between 1984 and 2018 were included in the meta-analysis. The overall prevalence of agranulocytosis and death caused by agranulocytosis were 0.4% (95% CI 0.3–0.6%) and 0.05% (95% CI 0.03–0.09%), respectively. The prevalence of agranulocytosis was moderated by sample size, study quality, year of publication, and that of data collection.ConclusionsThe prevalence of clozapine-associated agranulocytosis is low. Agranulocytosis-related death appears rare.