Thioridazine and sudden unexplained death in psychiatric in-patients

Abstract
Background: Sudden death has been linked to antipsychotic therapy but the relative risk associated with specific drugs is unknown. Aims: To assess the risk of sudden unexplained death associated with antipsychotic drug therapy and its relation to drug dose and individual agents. Method: A case-control study of psychiatric in-patients dying suddenly in five hospitals in the north-east of England and surviving controls matched for age, gender and mental disorder. Logistic regression analysis was used to identify significant risk factors, and odds ratios were calculated. Results: Sixty-nine case-control clusters were identified. Probable sudden unexplained death was significantly associated with hypertension, ischaemic heart disease and current treatment with thioridazine (adjusted odds ratio=5.3, 95% CI 1.7–16.2, P=0.004). There was no significant association with other individual antipsychotic drugs. Conclusions: Thioridazine alone was associated with sudden unexplained death, the likely mechanism being drug- induced arrythmia.