Identifying Hospital Admissions Due to Adverse Drug Events: Using a Computer-Based Monitor

BACKGROUND Hospital admissions due to adverse drug events (ADEs) are expensive, and many may be preventable, yet few institutions have ongoing surveillance for these events. OBJECTIVE To evaluate the use of a computer-based ADE monitor to identify admissions due to ADEs and to measure the associated costs. DESIGN Prospective cohort study in one tertiary care hospital. PARTICIPANTS All patients admitted to nine medical and surgical units in a tertiary care hospital over an 8-month period. MAIN OUTCOME MEASURE Admissions to the hospital due to an adverse drug event. METHODS A computer-based monitoring program generated alerts suggesting that an ADE might be present. A trained reviewer then evaluated the record. RESULTS Among the 3238 admissions, 76 (2.3%, 1.4% after adjusting for sampling) were found to be caused by an ADE. Of these ADEs, 78% were severe and 28% were preventable. Estimated costs were $16,177 per ADE, and $10,375 per preventable ADE; annualized costs to the hospital were $6.3 million per year for all ADEs, and $1.2 million for preventable ADEs. CONCLUSIONS Many admissions were caused by ADEs, although our point estimate undoubtedly represents a lower bound. These events were mostly severe, often preventable, and expensive. The computer-based monitoring system represents a practical approach for identifying ADEs that occur in outpatients and cause admission to the hospital.