Coronary Artery Calcium for Personalized Allocation of Aspirin in Primary Prevention of Cardiovascular Disease in 2019: The Multi-Ethnic Study of Atherosclerosis (MESA)

AUTHORS

Cainzos-Achirica M , Miedema MD , McEvoy JW , Al Rifai M , Greenland P , Dardari Z , Budoff M , Blumenthal RS , Yeboah J , Duprez DA , Mortensen MB , Dzaye O , Hong J , Nasir K , Blaha MJ , . Circulation. 2020 4 1; ().

PMID: 32233663 [PubMed].

ABSTRACT

Recent American College of Cardiology/American Heart Association (ACC/AHA) Primary Prevention Guidelines recommended considering low-dose aspirin therapy only among adults 40-70 years of age who are at higher atherosclerotic cardiovascular disease (ASCVD) risk but not at high risk of bleeding. However, it remains unclear how these patients are best identified. The present study aimed to assess the value of coronary artery calcium (CAC) for guiding aspirin allocation for primary prevention using 2019 aspirin meta-analysis data on CVD relative risk reduction (RRR) and bleeding risk. The study included 6,470 participants from the Multi-Ethnic Study of Atherosclerosis (MESA). ASCVD risk was estimated using the Pooled Cohort Equations (PCE) and 3 strata were defined: <5%, 5-20% and >20%. All participants underwent CAC scoring at baseline and CAC scores were stratified as =0, 1-99, ≥100 and ≥400. A 12% RRR in CVD events was used for 5-year number needed to treat (NNT) calculations, and a 42% relative risk increase in major bleeding events was used for 5-year number needed to harm (NNH) estimations. Only 5% of MESA participants would qualify for aspirin consideration for primary prevention according to ACC/AHA guidelines and using >20% estimated ASCVD risk to define “higher risk”. Benefit/harm calculations were restricted to aspirin-naïve participants <70 years not at high risk of bleeding (N=3,540). The overall NNT with aspirin to prevent one CVD event was 476 and the NNH was 355. The NNT was also greater than or similar to the NNH among estimated ASCVD risk strata. Conversely, CAC≥100 and CAC≥400 identified subgroups in which NNT was lower than NNH. This was true both overall (for CAC≥100, NNT=140 vs NNH=518) as well as within ASCVD risk strata. Also, CAC=0 identified subgroups in which the NNT was much higher than the NNH (overall, NNT=1,190 vs NNH=567). CAC may be superior to the PCE to inform allocation of aspirin in primary prevention. Implementation of current 2019 ACC/AHA guideline recommendations together with the use of CAC for further risk assessment may result in a more personalized, safer allocation of aspirin in primary prevention. Confirmation of these findings in experimental settings is needed.

Tags: alumni publications 2020