Gender differences in coronary plaque composition by coronary computed tomography angiography

Background: Coronary computed tomography angiography allows the differentiation of non-calcified (NCAP), calcified (CAP), and mixed coronary artery plaques (MCAP). Although males are thought to have a higher prevalence of atherosclerosis for a given age, there are currently few data regarding age-adjusted sex differences in plaque morphology and composition. Methods: We studied 1015 consecutive asymptomatic South Korean patients (49±10 years, 64% men) who underwent 64-slice coronary computed tomography angiography during a routine health evaluation. Coronary plaque characteristics were analyzed on a per-segment basis according to the modified AHA classification. Plaques with more than 50% calcified tissue were classified as CAP, plaques with less than 50% calcified tissue were classified as MCAP, and plaques without calcium were classified as NCAP. Multiple regression analysis was used to describe the cross-sectional association between sex and plaque-type burden (≥2 affected segments) after adjustment for age and other cardiovascular risk factors. Results: There was a greater prevalence of coronary plaque among men (13 vs. 4%, P<0.001). Males were more likely to have an increased burden of CAP (4 vs. 1%, P=0.01) and MCAP (5 vs. 1%, P<0.001), whereas the burden of NCAP was similar across sex (2 vs. 1%, P=0.28). After multivariable adjustment, men have six to seven times greater odds of having an increased burden of CAP and MCAP, whereas no sex difference was observed in the burden of NCAP. Conclusion: In this population of asymptomatic middle-aged Korean individuals, males had a significantly greater burden of MCAP and CAP. Future studies will determine whether these differences contribute to the accelerated cardiovascular risk observed in men.