The risk of adverse drug events and hospital-related morbidity and mortality among older adults with potentially inappropriate medication use

Abstract

Background: Inappropriate medication prescribing is a significant problem among older adults that may contribute to increased morbidity and mortality as well as increased costs of care. The development of specific lists of medications that are considered potentially inappropriate for older adults, such as the Beers criteria (BC), make it relatively easy to study prescribing practices in large numbers of patients.

Objective: The goal of this study was to determine how frequently adverse drug events (ADEs) in the acute care setting are related to BC medications and to determine if BC medication prescribing is significantly associated with the occurrence of ADEs and other negative outcomes in older hospitalized adults.

Methods: This was a retrospective review of patients aged > or =75 years admitted to 2 adult internal medicine services over 18 months (March 2000-August 2001). Data regarding general demographic and clinical information were collected; this information included place of residence before admission and at discharge; medications at admission, during the hospital stay, and at discharge; ADEs; length of stay; and in-hospital mortality Patient medical records were used to determine the occurrence of ADEs.

Results: : A total of 389 patients (68.9% female; mean age, approximately 79 years) were included. Of these 389 eligible patients, 107 (27.5%) were prescribed a total of 116 BC medications, and 124 (31.9%) experienced a total of 131 ADEs. Only 9.2% (12/131) of the ADEs were attributed to medications listed among the BC. After controlling for covariates, prescription of a BC medication was not significantly associated with experiencing an ADE (adjusted odds ratio [OR], 1.51; 95% CI, 0.98-2.35; P = 0.064), length of stay (adjusted OR, 1.03; 95% CI, 0.64-1.63; P = 0.91), discharge to higher levels of care (adjusted OR, 1.39; 95% CI, 0.82-2.34; P = 0.22), or in-hospital mortality (adjusted OR, 1.49; 95% CI, 0.77-2.92; P = 0.24).

Conclusions: Interventions targeted specifically at BC medications would have seemingly done little to change the risk of ADEs in this population. Interventions that are more comprehensive than the BC are necessary to reduce the risk of ADEs and the associated morbidity and mortality in acute care of the elderly.