Prescription medication use in older adults without major cardiovascular disease enrolled in the Aspirin in Reducing Events in the Elderly (ASPREE) Clinical Trial

Background: Efforts to minimize medication risks among older adults include avoidance of potentially inappropriate medications. Contemporary analysis of medication use in community-dwelling older people compared with the general population is lacking.

Participants: A total of 19,114 community-dwelling adults in Australia and the United States aged 70 years or older (65 years or older for U.S. minorities) without histories of major cardiovascular disease, cognitive impairment, or disability participated in a randomized, placebo-controlled trial of aspirin: ASPirin in Reducing Events in the Elderly study. Measurements Prescribed baseline medications obtained by self-report and medical record review were grouped by World Health Organization Anatomic and Therapeutic Chemical category. Potentially inappropriate medications were defined using a modified American Geriatrics Society Beers Criteria. Polypharmacy was defined as 5 or more medications, and hyperpolypharmacy defined as 10 or more medications. Cross-sectional descriptive statistics and adjusted odds ratios were computed.

Results: The median number of prescription medications per participant was three, regardless of age. Women had a higher medication prevalence. Cardiovascular drugs (primarily antihypertensives) were the most commonly reported (64%). Overall, 39% of the cohort reported taking at least one potentially inappropriate medication, with proton-pump inhibitors being the most commonly reported (21.2% of cohort). Of the cohort, 27% had polypharmacy, and 2% hyperpolypharmacy. Age 75 years or older, less than 12 years of education, hypertension, diabetes mellitus, chronic kidney disease, frailty, gastrointestinal complaint, and depressive symptoms were associated with an increased likelihood of potentially inappropriate medications and polypharmacy. For almost all medication classes, prevalence was equivalent or lower than the general older population.

Conclusion: Overall medication burden and polypharmacy are low in older adults free of major cardiovascular disease, disability, and cognitive impairment. The prevalence of potentially inappropriate medications is higher than previously reported and similar to more vulnerable populations as a result of the introduction of proton-pump inhibitors to the American Geriatrics Society Beers Criteria. Longitudinal follow-up is required to further understand the balance of benefits and risks for potentially inappropriate medications and polypharmacy in community-dwelling older people.