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

Psychiatry Res. 2021 May:299:113873. doi: 10.1016/j.psychres.2021.113873. Epub 2021 Mar 16.


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.

Keywords: cardiomyopathy; clozapine; incidence; myocarditis; risk factors.

MeSH terms

  • Antipsychotic Agents* / adverse effects
  • Cardiomyopathies* / chemically induced
  • Cardiomyopathies* / epidemiology
  • Clozapine* / adverse effects
  • Humans
  • Incidence
  • Myocarditis* / chemically induced
  • Myocarditis* / epidemiology
  • New Zealand / epidemiology
  • Retrospective Studies
  • Risk Factors


  • Antipsychotic Agents
  • Clozapine