Abstract 16061: Individualized Approach to Aspirin Therapy in Non-Diabetic Individuals Using Coronary Artery Calcium, Implications for Primary Prevention from the Multi-Ethnic Study of Atherosclerosis
Aspirin reduces CVD events in primary prevention but at the cost of increased bleeding. Improved risk stratification with coronary artery calcium (CAC) scoring offers potential to target patients with the most favorable risk/benefit profile. After exclusion of those who were on aspirin at baseline (n=1,580), diabetic (n=617), or missing data (n=5), 4,229 MESA participants were included in this analysis. Cardiovascular event rates were analyzed in both men and women after stratification by CAC score. The estimated 32% relative reduction in CHD for men and 17% reduction in CVD for women, as assumed by the USPSTF guidelines, were applied to the absolute event rates and compared to the absolute increased risk of bleeding on aspirin. Estimated 5-year increase in absolute bleeding rates were based on the rates of major bleeding (0.28%) and “non-trivial” bleeding (0.76%) seen in the 2 most recent meta-analysis of aspirin for the primary prevention of cardiovascular disease. Using the estimated absolute risk reduction and absolute increase in bleeding rate, 5-year number-needed-to-treat (NNT) and 5-year number-needed-to-harm (NNH) estimations were calculated (Table 1).
Conclusion: In non-diabetic MESA participants not on aspirin for the primary prevention of CVD, the most favorable estimated risk/benefit profile for aspirin therapy occurred in participants with a calcium score of a 100 or greater. Conversely, patients with CAC=0 appear to have a higher likelihood of bleeding compared to the potential of preventing a cardiovascular event.
- © 2012 by American Heart Association, Inc.