Positive coronary artery calcium (CAC>0) was associated with a heterogeneous increase in 10-year CVD risk, with 69.2% of low ASCVD risk individuals showing a ≥2.5% increase in CVD risk.
Cohort (n=3,328)
Does the presence of positive coronary artery calcium (CAC > 0) increase the 10-year risk of incident cardiovascular disease across different baseline ASCVD risk profiles?
A machine-learning causal forest model demonstrates that positive coronary artery calcium significantly increases 10-year CVD risk even in individuals classified as low risk by standard ASCVD equations, suggesting a potential benefit for CAC screening in this subgroup.
BACKGROUND: Coronary artery calcium (CAC) has been widely recognized as an important predictor of cardiovascular disease (CVD). Given the finite resources, it is important to identify individuals who would receive the most benefit from detecting positive CAC by screening. However, the evidence is limited as to whether the burden of positive CAC on CVD differs by multidimensional individual characteristics. We sought to investigate the heterogeneity in the association between positive CAC and incident CVD. METHODS: This cohort study included adults from MESA (Multi-Ethnic Study of Atherosclerosis) ages ≥45 years and free of cardiovascular disease. After propensity score matching in a 1:1 ratio, we applied a machine learning causal forest model to (1) evaluate the heterogeneity in the association between positive CAC and incident CVD, and (2) predict the increase in CVD risk at 10-years when CAC>0 (versus CAC=0) at the individual level. We then compared the estimated increase in CVD risk when CAC>0 to the absolute 10-year atherosclerotic CVD (ASCVD) risk calculated by the 2013 American College of Cardiology/American Heart Association pooled cohort equations. RESULTS: Across 3328 adults in our propensity score-matched analysis, our causal forest model showed the heterogeneity in the association between CAC>0 and incident CVD. We found a dose-response relationship of the estimated increase in CVD risk when CAC>0 with higher 10-year ASCVD risk. Almost all individuals (2293 of 2428 94.4%) with borderline risk of ASCVD or higher showed ≥2.5% increase in CVD risk when CAC>0. Even among 900 adults with low ASCVD risk, 689 (69.2%) showed ≥2.5% increase in CVD risk when CAC>0; these individuals were more likely to be male, Hispanic, and have unfavorable CVD risk factors than others. CONCLUSIONS: The expected increases in CVD risk when CAC>0 were heterogeneous across individuals. Moreover, nearly 70% of people with low ASCVD risk showed a large increase in CVD risk when CAC>0, highlighting the need for CAC screening among such low-risk individuals. Future studies are needed to assess whether targeting individuals for CAC measurements based on not only the absolute ASCVD risk but also the expected increase in CVD risk when CAC>0 improves cardiovascular outcomes.
Inoue et al. (Mon,) conducted a cohort in Cardiovascular disease (n=3,328). Positive Coronary Artery Calcium (CAC>0) vs. CAC=0 was evaluated on Incident CVD. Positive coronary artery calcium (CAC>0) was associated with a heterogeneous increase in 10-year CVD risk, with 69.2% of low ASCVD risk individuals showing a ≥2.5% increase in CVD risk.