Incidence and investigation of potential risk-factors for clozapine-associated myocarditis and cardiomyopathy in a New Zealand cohort.

Clozapine is a uniquely effective antipsychotic indicated for treatment-resistant schizophrenia. However, its use is underutilised and often delayed for years due to potential adverse reactions including myocarditis and cardiomyopathy. The purpose of this study was to conduct a retrospective review of the clinical records of patients initiating clozapine in the Auckland District Health Board (ADHB) region to determine the incidence of clozapine-associated myocarditis and cardiomyopathy and to identify potential risk factors associated with these cardiotoxicities. The incidence of clozapine-associated myocarditis and cardiomyopathy over a two-year period in the ADHB region was 3.8% and 1.3% respectively.