Antipsychotic drugs and heart muscle disorder in international pharmacovigilance: data mining study.

OBJECTIVES To examine the relation between antipsychotic drugs and myocarditis and cardiomyopathy. DESIGN Data mining using bayesian statistics implemented in a neural network architecture. SETTING International database on adverse drug reactions run by the World Health Organization programme for international drug monitoring. MAIN OUTCOME MEASURES Reports mentioning antipsychotic drugs, cardiomyopathy, or myocarditis. RESULTS A strong signal existed for an association between clozapine and cardiomyopathy and myocarditis. An association was also seen with other antipsychotics as a group. The association was based on sufficient cases with adequate documentation and apparent lack of confounding to constitute a signal. Associations between myocarditis or cardiomyopathy and lithium, chlorpromazine, fluphenazine, haloperidol, and risperidone need further investigation. CONCLUSIONS Some antipsychotic drugs seem to be linked to cardiomyopathy and myocarditis. The study shows the potential of bayesian neural networks in analysing data on drug safety.