Prevalence of Acetylsalicylic Acid Use for Primary Prevention of Cardiovascular Disease Amongst Older Adults From 2017—2021: a Retrospective Cross-Sectional Study

BACKGROUND: Three landmark trials on the use of acetylsalicylic acid (ASA) for primary prevention of cardiovascular disease (CVD) were published in 2018. Since then, major clinical practice guidelines have been updated with recommendations against the routine use of ASA for primary CVD prevention, particularly in older adults. However, little is known about the uptake of this evidence into real world practice. The purpose of this study was to assess the change in ASA usage for primary prevention of CVD in older adults between 2017 and 2021. METHODS: A retrospective cross-sectional study of ASA use for primary prevention in ambulatory older adults without known CVD in an urban Canadian city was conducted. RESULTS: Seven hundred and fifty-six participants were included. The mean age was 78.9 years (standard deviation 7.9) and 64.8% were female. One hundred and thirty (17.2%) participants used ASA for primary prevention, including 20.3% in 2017, 17.0% in 2018, 21.8% in 2019, 16.3% in 2020, and 11.0% in 2021 (p = .061). Female sex was associated with lower ASA use (odds ratio [OR] 0.44, 95% confidence interval [CI] 0.29–0.68) and hypertension was associated with higher ASA use (OR 2.72, 95% CI 1.73–4.29). CONCLUSIONS: Use of ASA for primary CVD prevention in older Canadians decreased between 2017 and 2021, suggesting an uptake of clinical trial data and practice guideline recommendations. Focusing on deprescribing of ASA for primary CVD prevention continues to be warranted, given the risks associated with ASA in this population.