Background: Adverse drug events (ADEs) occur often in hospitals, causing high morbidity and a longer length of stay (LOS), and are costly. However, most studies on the impact of ADEs have been conducted in tertiary referral centers, which are systematically different than community hospitals, where the bulk of care is delivered, and most available data about ADE costs in any setting are dated. Costs in community settings are generally lower than in academic hospitals, and the costs of ADEs might be as well. To assess the additional costs and LOS associated with patients with ADEs, a multicenter retrospective cohort study was conducted in six community hospitals with 100 to 300 beds in Massachusetts during a 20-month observation period (January 2005-August 2006).
Methods: A random sample of 2,100 patients (350 patients per study site) was drawn from a pool of 109,641 patients treated within the 20-month observation period. Unadjusted and adjusted cost of ADEs as well as LOS were calculated.
Results: ADEs were associated with an increased adjusted cost of $3,420 and an adjusted increase in length of stay (LOS) of 3.15 days. For preventable ADEs, the respective figures were +$3,511 and +3.37 days. The severity of the ADE was also associated with higher costs--the costs were +$2,852 for significant ADEs (LOS +2.77 days), +$3,650 for serious ADEs (LOS +3.47 days), and +$8,116 for life-threatening ADEs (LOS +5.54 days, all p < .001).
Conclusions: ADEs in community hospitals cost more than $3,000 dollars on average and an average increase of LOS of 3.1 days--increments that were similar to previous estimates from academic institutions. The LOS increase was actually greater. A number of approaches, including computerized provider order entry and bar coding, have the potential to improve medication safety.