Background: Adverse drug events (ADEs) are a primary cause of significant morbidity, mortality, and healthcare utilization in older adults.
Objective: The objective of this study was to evaluate the clinical outcomes and cost of ADEs during hospitalization in older adults.
Methods: Discharges for patients aged 65 years 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.
Results: 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.
Conclusions: 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.