Abstract 18737: Coronary Artery Calcium for Allocation of Aspirin in Light of the 2022 USPSTF Guideline Recommendations: Results From the Multi-Ethnic Study of Atherosclerosis (MESA)

Abstract

Introduction: The 2022 USPSTF guidelines issued a grade C recommendation for aspirin in patients aged 40-59 and recommended against its use in patients ≥ 60 years. We sought to assess if coronary artery calcium (CAC) would allow for personalized allocation of aspirin. Methods: Using MESA, aspirin naïve participants without high-risk bleeding features were identified. Participants were grouped by age into <60, ≥ 60 and stratified by CAC and ASCVD risk. The number needed to treat (NNT 5 ) and number needed to harm (NNH 5 ) was assessed by applying a 11% relative risk reduction in CVD and a 44% relative risk increase in major bleeding (2022 USPSTF meta-analysis) to the observed CVD and bleeding events from MESA Results: Of 6,814 participants, 4,506 met inclusion criteria. 2,235 were <60 years and 2,268 were ≥ 60 years. Figure-1 displays the interplay between baseline estimated ASCVD risk and CAC burden. In participants <60 years of age, both CAC and ASCVD risk >10% identified subgroups in whom the NNT was lower than the NNH: CAC 1-99 (NNT 5 -313, NNH 5 -517); CAC ≥100 (NNT 5 -152, NNH 5 -367); ASCVD risk >10% (NNT 5 -155, NNH 5 -554) Fig-1. In those ≥ 60 years CAC ≥100 identified subgroups with a lower NNT 5 -128 than NNH 5 -168, while ASCVD risk stratification did not. 6% of adults <60 years with <10% ASCVD risk and 30.3% of adults ≥ 60 years who had CAC ≥100, and who demonstrated benefit from the use of Aspirin, would not qualify for the use of aspirin using only ASCVD risk as per the 2022 USPSTF guideline recommendations. Conclusions: CAC identifies subgroups of patients <60 as well as those ≥ 60 years who would derive a net benefit from aspirin in primary prevention. A significant proportion of patients will be missed if only ASCVD risk scores are used for allocation of aspirin. CAC should be used to risk stratify individuals to personalize the allocation of aspirin