Systematic review of racial disparities in clozapine prescribing

To conduct a systematic review of published evidence on clozapine prescribing disparities across racial and ethnic categories, estimate the size of these disparities, and assess possible causes to inform future monitoring and intervention.

Electronic databases (MEDLINE, Embase, PsycINFO, Web of Science) were searched for directly relevant studies. Three independent reviewers selected studies: (1) of US samples; (2) directly addressed ethnic and/or racial disparities in prescribing of antipsychotic medications; (3) identified specific ethnic and/or racial groups (e.g. White, Blacks, Hispanics, non-Hispanic etc.); (4) reported clozapine prescription rates and (5) reported relevant covariates (i.e. gender, age, co-morbidities etc.).

16 studies met our eligibility criteria. All studies reported clozapine underutilization in ethnic and racial minority patients when compared to their white counterparts. These findings remained consistent despite different time periods, designs, data set types, and after controlling for relevant covariates such as: length of hospital stay, institutional setting, and disease severity.

The reasons for underutilization of clozapine in minority patients remain unclear. Various contributors can be categorized as: clinician-related factors (e.g. prescriber lack of experience), patient-related factors (e.g. distrust or suspicion of clinician), and institution-related factors (e.g. state operated facilities). Direct examination of these factors can help inform efforts to reduce clozapine prescription disparities.