Potential Adverse Drug Events in an Indigent and Homeless Geriatric Population

Abstract

OBJECTIVE: To identify potential adverse drug events (ADEs) in a geriatric ambulatory population using the modified Beers criteria. METHODS: This is a cross-sectional study of an indigent and homeless geriatric population served by a network of six primary healthcare clinics with clinical pharmacy services. Medical records of patients ≥65 years old visiting the clinics between December 1999 and April 2000 were retrospectively reviewed by a clinical pharmacist. Medications meeting the modified Beers criteria were evaluated for the most common drug classes involved, severity potential, and dose or disease state restrictions. Following the identification of medications meeting Beers criteria, the pharmacist left a written recommendation regarding use of alternative drugs or doses in the medical record. Physician acceptance of pharmacy recommendations was also evaluated. RESULTS: Medical records of 146 patients (71.9% women, average age 72.6 ± 6.7 y) were reviewed. Overall, 52 patients (35.6%) had 70 medications with the potential for causing an ADE based on the modified Beers criteria. The most commonly identified medication classes were narcotic analgesics (20.0%), antihypertensives (20.0%), and antihistamines (14.3%). Fifteen of these medications (21.4%) had a high severity potential. Identified medications met the following modified Beers criteria: 41.4% were inappropriate in a specific disease state, 38.6% were inappropriate for the elderly, 10.0% exceeded maximum dosage guidelines, and 10.0% were inappropriate for both the elderly and the patient's disease state. Approximately 60% of pharmacy recommendations were accepted by physicians. CONCLUSIONS: The modified Beers criteria are a useful tool for reviewing medical records to identify potential ADEs in an ambulatory geriatric population.