Sex Differences in Aortic Arch Calcification With Zero Coronary Artery Calcium

Studies have linked aortic calcification to an increased risk of all-cause mortality and cardiovascular mortality. There is minimal evidence evaluating the sex differences in the prevalence of aortic arch calcification (AAC) in relation to zero coronary artery calcium (CAC).

This study included participants from the Multi-Ethnic Study of Atherosclerosis (MESA) exam 5, of which 2,564 underwent non-contrast chest computed tomography scans. We utilised the CAC and AAC scores measured by the Agatston method to evaluate sex differences in AAC among participants overall, and among those with zero CAC. Regression analysis was performed, adjusting for covariates, to evaluate the sex difference.

The average age of the 2,564 participants was 69.2±9.2 years, 46% were women, 38% were White, 13% were Chinese, 27% were Black, and 22% were Hispanic/Latino. A total of 813 (32%) had a CAC of zero. The prevalence of AAC was higher in women than men, both in the zero CAC population (87% vs 80%) and overall (92% vs 90%). The median AAC was additionally higher in women in the overall population (217 vs 212) and in the CAC zero population (60 vs 20). After controlling for covariates, the estimated average AAC was 0.51 times lower in men than women (95% confidence interval 0.36-0.72; p<0.001) in the CAC zero population.

This study demonstrated that the prevalence of aortic arch calcium is higher in women compared to men. In a subset of the population with zero CAC, the average amount of AAC is significantly higher in women. In the future, event analysis should be done to determine whether these sex differences in AAC may partially explain the sex differences in the prediction of atherosclerotic cardiovascular disease events.