Comparing coronary artery cross-sectional area among asymptomatic South Asian, White, and Black participants: the MASALA and CARDIA studies

BACKGROUND

South Asian individuals have high risk of atherosclerotic cardiovascular disease (ASCVD). Some investigators suggest smaller coronary artery size may be partially responsible.

METHODS

We compared the left anterior descending (LAD) artery cross-sectional area (CSA) (lumen and arterial wall) among South Asians in the Mediators of Atherosclerosis in South Asians Living in America (MASALA) study with White and Black participants in the Coronary Artery Risk Development in Young Adults (CARDIA) 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 determine whether race/ethnicity was associated with LAD CSA after adjusting for demographic factors, BMI, height, coronary artery calcium (CAC), and traditional cardiovascular risk factors.

RESULTS

Our sample included 3,353 participants: 513 self-identified as South Asian (44.4% women), 1286 as Black (59.6% women), and 1554 as White (53.5% women). After adjusting for age, BMI, height, there was no difference in LAD CSA between South Asian men and women compared to White men and women, respectively. After full adjustment for CVD risk factors, LAD CSA values were: South Asian women (19.9 mm2, 95% CI [18.8 - 20.9]) and men (22.3 mm2, 95% CI [21.4 - 23.2]; White women (20.0 mm2, 95% CI [19.4-20.5]) and men (23.6 mm2, 95% CI [23.0-24.2]); and Black women (21.6 mm2, 95% CI [21.0 - 22.2]) and men (26.0 mm2, 95% CI [25.3 - 26.7]). Height, BMI, hypertension, CAC, and age were positively associated with LAD CSA; current and former cigarette use were inversely associated.

CONCLUSIONS

South Asian men and women have similar LAD CSA to White men and women, and smaller LAD CSA compared to Black men and women, respectively, after accounting for differences in body size. Future studies should determine whether LAD CSA is associated with future ASCVD events.

Body mass index in young adulthood and mid-life cardiovascular risk factors in South Asian American adults: The MASALA study

The association of self-reported BMI at age 20, at age 40, the highest BMI within the past 3 years, and current BMI with current mid-life cardiovascular risk factors and coronary artery calcium (CAC) was evaluated among 1148 South Asian American participants (mean age 57 years) in the MASALA study. A 1 kg/m² higher BMI at age 20 was associated with higher odds of hypertension (aOR 1.07, 95% CI 1.03-1.12), pre-diabetes/diabetes (aOR 1.05 [1.01-1.09]), and prevalent CAC (aOR 1.06 [1.02-1.11]) in mid-life. Associations were similar for all BMI measures. Weight across young adulthood is associated with mid-life cardiovascular health in South Asian American adults.

Effects of moderate to vigorous intensity cycling on appetite, ad libitum energy intake and appetite-related hormones in healthy South Asian and white European men

Compensatory changes in appetite and energy intake do not appear to occur in the short-term after acute exercise; however, responses have not been compared in South Asians, a group at high risk of central obesity and type 2 diabetes, with white Europeans. This study examined appetite perceptions, energy intake and appetite-related hormones after moderate-to-vigorous intensity cycling in South Asian versus white European men. Fifteen South Asians (mean(SD) 29(8) years; 25.4(4.5) kg m^-2) and fifteen white Europeans (33(10) years; 26.1(3.8) kg m^-2) matched for age and body mass index completed two 7 h trials (control and exercise). Participants rested throughout both trials apart from completing 60 min cycling at 2-3 h in the exercise trial. A standardised breakfast was consumed at 0 h and an ad libitum buffet meal at 4 h. Appetite perceptions and appetite-related hormones were measured at predetermined intervals. Exercise suppressed acylated ghrelin (d = 0.19, P < 0.001) and increased total peptide YY (PYY) (d = 0.14, P = 0.004), insulin (d = 0.09, P = 0.046) and glucose concentrations (d = 0.31, P < 0.001) (main effect of trial), without stimulating compensatory increases in energy intakes in either group (group-by-trial interactions). South Asians exhibited lower absolute energy intake and higher insulin concentrations than white Europeans (main effect group d ≥ 0.63, P ≤ 0.003), whereas group-by-time interactions revealed lower acylated ghrelin concentrations at 3 and 4 h (d ≥ 0.75, P ≤ 0.038) and higher glucose concentrations at 0.75 and 2 h (d ≥ 0.67, P ≤ 0.008) in South Asian than white European men. These findings demonstrate that acute exercise induces a short-term energy deficit and similar appetite responses in South Asian and white European men.

Acculturation is Associated with Dietary Patterns in South Asians in America

Acculturation may influence diet pattern, a risk factor for cardiometabolic disease. We assessed whether strength of traditional cultural beliefs and practices, a robust measure of acculturation, affects diet pattern among South Asians in America. With data from the Mediators of Atherosclerosis in South Asians Living in America (MASALA) cohort, we used ordinal logistic regression to assess the association between strength of traditional cultural beliefs, 6 cultural practices and diet pattern. Of 892 participants, 47% were women. Weaker traditional cultural beliefs [OR(95%CI) 1.07(1.04,1.10)] and cultural practices (p < 0.05) were associated with consuming more of the Animal Protein dietary pattern and less [0.95(0.93,0.97)] of the Fried snacks, Sweets, High-fat dairy (FSHD) pattern (P < 0.05). South Asians in America with stronger traditional cultural beliefs and practices were more likely to consume the FSHD pattern. Prevention programs may consider dietary pattern modification as part of comprehensive risk reduction in South Asians.

Effectiveness of a Cultural Stroke Prevention Program in the United States-South Asian Health Awareness About Stroke (SAHAS)

There are few stroke education programs focused on the South Asian population in the United States. The South Asian Health Awareness about Stroke (SAHAS) program was developed to provide culturally appropriate stroke education to South Asians from 2014 to 2017. Participants recruited for the SAHAS program were educated through a uniquely developed, culturally-specific, educational presentation. Each participant was asked to complete identical educational questionnaires both before (pre-) and after (post-) the intervention, which were then scored and evaluated. Overall, the 357 participants who completed the SAHAS program had a significant, modest 9% improvement in questionnaire score (p < 0.0001). After adjusting for confounders, those ≤ 60 years had a 2.9-point greater increase in score than those > 60 (p < 0.0001). Having programs targeted and developed for specific minority groups with an emphasis on familial commitment and active participation may aid in raising awareness and reducing the elevated adverse stroke outcomes in South Asians.