Coronary Artery Calcium Density and Cardiovascular Events by Volume Level: The MESA

BACKGROUND: The Agatston coronary artery calcium (CAC) score provides robust cardiovascular disease risk prediction but upweights plaque area by a density factor. Density, however, has been shown to be inversely associated with events. Using CAC volume and density separately improves risk prediction, but it is unclear how to apply this method clinically. We aimed to evaluate the association between CAC density and cardiovascular disease across the spectrum of CAC volume to better understand how to incorporate these metrics into a single score. METHODS: We performed an analysis of MESA (Multi-Ethnic Study of Atherosclerosis) participants with detectable CAC to evaluate the association between CAC density and events by level of CAC volume using multivariable Cox regression models. RESULTS: was not significant (hazard ratio, 0.82 per unit of density [95% CI, 0.55-1.22]). CONCLUSIONS: is a potentially clinically useful cut point. Further study is needed to integrate these findings into a unified CAC scoring method.