Association of Adverse Drug Events with Hospitalization Outcomes and Costs in Older Adults in the USA using the Nationwide Readmissions Database.

Abstract

Adverse drug events (ADEs) are a primary cause of significant morbidity, mortality, and healthcare utilization in older adults. The objective of this study was to evaluate the clinical outcomes and cost of ADEs during hospitalization in older adults. Discharges for patients aged 65years or older were identified in the 2014 Nationwide Readmissions Database. ADEs were selected based on a previously developed algorithm of 442 unique diagnoses and external causes of injury codes. Patients were categorized into ADE or non-ADE groups. Regression models were used for a multivariable analysis for each outcome metric, which included all-cause readmission, in-hospital mortality, length of stay, and costs. The study included 3,832,322 patients. Among these patients, 203,432 (5.3%) had at least one ADE during hospitalization. The majority of ADEs were related to broad categories of "medications affecting blood constituents" (22%) and "adverse effects of biological and medicinal substances in therapeutic use" (23%). In adjusted models, older adults with ADEs during hospitalization had a 25% (p < 0.0001) and 9% (p < 0.0001) higher odds of readmission and in-hospital mortality, respectively, as compared with those without ADEs. A 17% (p < 0.0001) increase in the length of stay was estimated in the ADE group and 1% point estimate (p > 0.05) rise in cost was observed in the ADE group when compared with the non-ADE group. ADEs have a substantial burden on in-patient care of older adults both clinically (increased readmission, in-hospital mortality, and length of stay) and financially. Targeted interventions can help to prevent ADEs and, consequently, the associated clinical and economic burden.