Proportion of Hospital Deaths Associated with Adverse Events

Objectives: To determine the fraction of hospital deaths potentially associated with the occurrence of adverse events (AE). Design: A paired (1:1) case-control study. Setting: An 800-bed, teaching tertiary care hospital. Patients: All patients older than 14 years admitted to the hospital between January 1, 1990, and January 1, 1991, were eligible. All 524 consecutive deaths (death rate of 3.74%) that occurred in the hospital comprised the case group. For each case, a control patient was matched for both primary diagnosis on admission and admission date. Measurements: The proportion of hospital deaths associated with adverse events (defined as problems of any nature and seriousness faced by the patient during hospitalization, and potentially traceable to clinical or administrative management) was estimated from attributable risks adjusted for age, sex, service, severity of illness, length of stay, and quality of the medical record. Results: For stays longer than 48 hours, the adjusted attributable risk for all adverse events was estimated to be 0.51 (0.40–0.61). When the data were stratified according to the category of adverse event, the attributable risks remained significant except for administrative problems. The greatest proportion of deaths associated with adverse events was observed for surgical adverse events [0.56 (0.38–0.71)] and nosocomial infection [0.22 (0.14–0.28)]. Conclusions: A significant proportion of intrahospital deaths were associated with AE. These results suggest the need to consider programs focused on the prevention of mortality from AE.