National Trends in Aspirin Use and Expenditures in the United States: Analysis of The Medical Expenditure Panel Survey 2000-2021.

Introduction: Since its invention in 1897, aspirin (ASA) has been the most widely used and cost-effective antiplatelet agent to prevent and treat atherosclerotic cardiovascular disease (ASCVD). We aimed to study the trends and expenditures associated with ASA use in the USA.

Methods: We conducted a serial cross-sectional analysis using the Medical Expenditure Panel Survey data from January 2000 to December 2021, focusing on adults aged ≥ 40 years. Total and out-of-pocket expenditures associated with ASA were estimated to 2021 US dollars (USD). Trends, demographics, and predictors of ASA use among patients with and without ASCVD were also evaluated.

Results: A total of 53 million adults were identified during the study period. The number of ASA users increased from 2.9 million to 6.6 million with increased female (36.7%-49.7%; p trend = 0.02) and African American (13%-18.9%; p trend = 0.03) representation amongst all ASA users during the survey period. The use of low-dose ASA increased, while high-dose ASA declined significantly. Only 50% of all ASA users had known ASCVD. The most prevalent ASA users among patients with ASCVD were those aged ≥ 70 years, while patients without ASCVD, it was the 50-69 age group. The total annual expenditure on ASA averaged approximately 60 million USD, with 27.3 million USD out-of-pocket.

Conclusion: Total and low-dose (81 mg) ASA use has increased, while high-dose (325 mg) ASA has declined. ASA use for primary prevention has risen among adults aged 50-69 years, and patients ≥ 70 years continue to use ASA without known ASCVD. Further studies are needed to understand the implications of increased ASA use, especially among those without ASCVD.