Abstract 11370: Comparing Coronary Artery Cross-Sectional Area Among Asymptomatic South Asian, White, and Black Participants: The Masala and Cardia Studies

Abstract

Introduction: South Asian individuals have high risk of atherosclerotic cardiovascular disease (ASCVD). Some investigators suggest smaller coronary artery size may be partially responsible. Hypothesis: We hypothesized that South Asian participants would have smaller left anterior descending artery (LAD) cross sectional area (CSA) than Black and White participants, and that this association would be attenuated after adjusting for body size (BMI and height) and cardiovascular risk factors. Methods: We compared the LAD CSA (lumen and arterial wall) among South Asians in the Mediators of Atherosclerosis in South Asians Living in America study with White and Black participants in the Coronary Artery Risk Development in Young Adults study, adjusting for BMI, height, and other ASCVD risk factors. We used thin-slice non-contrast cardiac computed tomography to measure LAD CSA. We used linear regression models to explore differences by race/ethnicity in LAD CSA after adjusting for demographic, BMI, height, coronary artery calcium (CAC), and ASCVD risk factors. Results: We included 3,353 participants: 513 South Asian (44% women), 1286 Black (60% women), and 1554 White (54% women). After adjusting for age, BMI, height, there was no difference in LAD CSA between South Asian and White participants by sex. However, South Asian participants had smaller LAD CSA compared to Black participants by sex. After full adjustment for ASCVD risk factors, LAD CSA values were: South Asian women (19.9 mm 2 , 95% CI [18.8 - 20.9]) and men (22.3 mm 2 , 95% CI [21.4 - 23.2]; White women (20.0 mm 2 , 95% CI [19.4 - 20.5]) and men (23.6 mm 2 , 95% CI [23.0 - 24.2]); and Black women (21.6 mm 2 , 95% CI [21.0 - 22.2]) and men (26.0 mm 2 , 95% CI [25.3 - 26.7]) ( Figure 1 ). Conclusions: After accounting for differences in body size, South Asian participants had smaller LAD CSA compared to Black participants, but similar to White participants. Future studies should determine whether LAD CSA is associated with future ASCVD events.