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Currently, South Asia accounts for a quarter of the world population, yet it already claims ≈60% of the global burden of heart disease. Besides the epidemics of type 2 diabetes mellitus and coronary heart disease already faced by South Asian countries, recent studies suggest that South Asians may also be at an increased risk of heart failure (HF), and that it presents at earlier ages than in most other racial/ethnic groups. Although a frequently underrecognized threat, an eventual HF epidemic in the densely populated South Asian nations could have dramatic health, social and economic consequences, and urgent interventions are needed to flatten the curve of HF in South Asia. In this review, we discuss recent studies portraying these trends, and describe the mechanisms that may explain an increased risk of premature HF in South Asians compared with other groups, with a special focus on highly relevant features in South Asian populations including premature coronary heart disease, early type 2 diabetes mellitus, ubiquitous abdominal obesity, exposure to the world's highest levels of air pollution, highly prevalent pretransition forms of HF such as rheumatic heart disease, and underdevelopment of healthcare systems. Other rising lifestyle-related risk factors such as use of tobacco products, hypertension, and general obesity are also discussed. We evaluate the prognosis of HF in South Asian countries and the implications of an anticipated HF epidemic. Finally, we discuss proposed interventions aimed at curbing these adverse trends, management approaches that can improve the prognosis of prevalent HF in South Asian countries, and research gaps in this important field.

Background: Diet quality is an important risk factor for type 2 diabetes (T2D) and cardiovascular disease (CVD). Little is known about the diet quality of South Asians in the United States, a group with higher rates of T2D and CVD compared with other racial/ethnic groups., Objective: This study determined whether diet quality differs between South Asian adults in the Mediators of Atherosclerosis in South Asians Living in America (MASALA) Study and whites, Chinese Americans, African Americans, and Hispanics in the Multi-Ethnic Study of Atherosclerosis (MESA)., Methods: Cross-sectional data from 3926 participants free of CVD from MESA visit 5 (2010-2011) and 889 South Asian participants from MASALA visit 1 (2010-2013) were pooled. Diet quality was assessed using the Alternative Healthy Eating Index (AHEI-2010) derived using FFQs. Multivariable linear regression models adjusted for age, sex, and total energy intake were used to compare mean differences in diet quality between the racial/ethnic groups., Results: MESA participants were, on average, 14 y older than MASALA participants. The adjusted mean (95% CI) scores for the AHEI-2010 were 70.2 (69.5, 70.9) among South Asians, 66.2 (66.3, 68.2) among Chinese Americans, 61.1 (60.7, 61.6) among whites, 59.0 (58.4, 59.7) among Hispanics, and 57.5 (56.9, 58.1) among African Americans. The mean AHEI scores among South Asians were 3.1 (1.8, 4.3), 9.2 (8.3, 10.1), 11.2 (10.2, 12.3), and 12.8 (11.8, 13.7) points higher compared with Chinese Americans, whites, Hispanics, and African Americans, respectively., Conclusions: South Asian adults in the United States have a higher diet quality compared with other racial/ethnic groups. This paradoxical finding is not consistent with the observed higher rates of T2D and CVD compared with other groups. This is further evidence of the importance of studying the South Asian population to better understand the causes of chronic disease not explained by diet quality., (Copyright © The Author(s) 2020.)

Objective: South Asians have a higher prevalence of type 2 diabetes compared with other race/ethnic groups. Body composition is associated with the risk for type 2 diabetes. Differences in body composition between South Asians and other race/ethnic groups are one hypothesized mechanism to explain the disproportionate prevalence of type 2 diabetes in this population., Research Design and Methods: This study used data from the Mediators of Atherosclerosis in South Asians Living in America (MASALA) and the Multi-Ethnic Study of Atherosclerosis (MESA) cohorts to determine whether body composition mediated the elevated prevalence of impaired fasting glucose and type 2 diabetes in South Asians. Participants ( n = 2,615) with complete body composition data were included. Ordinal logistic regression models were calculated to determine the odds for glycemic impairment in South Asians compared with the MESA cohort., Results: In multivariate models, South Asians had a significantly higher prevalence of glycemic impairment and type 2 diabetes compared with all four race/ethnic groups included in the MESA ( P < 0.001 for all). In unadjusted and multivariate adjusted models, South Asians had higher odds for impaired fasting glucose and type 2 diabetes compared with all other race/ethnic groups ( P < 0.001 for all). The addition of body composition measures did not significantly mitigate this relationship., Conclusions: We did not identify strong evidence that accounting for body composition explains differences in the risk for type 2 diabetes. Future prospective studies of the MESA and MASALA cohorts are needed to understand how adipose tissue impacts the risk for type 2 diabetes and how to best assess this risk., (© 2019 by the American Diabetes Association.)

Background: South Asians have disproportionately high rates of cardiovascular disease. Dyslipidemia, a contributing factor, may be influenced by lifestyle, which can vary by religious beliefs. Little is known about South Asian religions and associations with dyslipidemia., Methods: Cross-sectional analyses of the MASALA study (n = 889). We examined the associations between religious affiliation and cholesterol levels using multivariate linear regression models. We determined whether smoking, alcohol use, physical activity, and dietary pattern mediated these associations., Results: Mean LDL was 112 ± 32 mg/dL, median HDL was 48 mg/dL (IQR:40-57), and median triglycerides was 118 mg/dL (IQR:88-157). Muslims had higher LDL and triglycerides, and lower HDL, while participants with no religious affiliation had lower LDL and higher HDL. The difference in HDL between Muslims and those with no religious affiliation was partly explained by alcohol consumption., Conclusions: Religion-specific tailoring of interventions designed to promote healthy lifestyle to reduce cholesterol among South Asians may be useful.

Background South Asians have a relatively high prevalence of coronary artery calcium ( CAC ) compared with other race/ethnic groups. We determined CAC incidence and progression among South Asians, and compared them with 4 race/ethnic groups. Methods and Results Data from the MASALA (Mediators of Atherosclerosis in South Asians Living in America) study were used to calculate CAC incidence and progression rates and any CAC change. Data from the MESA (Multi-Ethnic Study of Atherosclerosis) were used to compare the CAC incidence and progression rates. A total of 698 South Asians had repeat CAC measurements after 4.8±0.8 years. Among those with no CAC at baseline, the age-adjusted CAC incidence was 8.8% (95% CI, 6.8-10.8%) in men and 3.6% (2.5-4.8%) in women. The median annual CAC progression was 26 (interquartile range, 11-62) for men and 13 (interquartile range, 4-34) for women. Compared with MESA , age-adjusted CAC incidence was similar in South Asian men compared with white, black, and Latino men, but significantly higher than Chinese men (11.1% versus 5.7%, P=0.008). After adjusting for age, diabetes mellitus, hypertension, and statin medication use, Chinese, black, and Latino men had significantly less CAC change compared with South Asian men, but there were no differences between South Asian and white men. There was no difference in CAC incidence or progression between South Asian women and women in MESA . Conclusions South Asian men had greater CAC change than Chinese, black, and Latino men but similar change to that of whites after adjusting for traditional risk factors.

Background: Consumption of low-calorie sweeteners (LCS) has increased in the US and is associated with cardiometabolic risk. No data exist on LCS consumption in South Asians., Aim: The aim of this study was to assess the prevalence of LCS use across socio-demographic characteristics, chronic disease status, and cardiometabolic risk factors., Methods: Cross-sectional analyses were conducted using data from the Mediators of Atherosclerosis in South Asians Living in America study ( N = 892; 47% women; mean age = 55 (standard deviation = 9.4) y). Chi-squared and ANOVA tests were used to compare LCS consumption across socio-demographic characteristics and cardiometabolic risk factors., Results: Twenty-two percent of participants reported LCS use, with higher consumption among men and those with longer residency in the US. LCS use was associated with adiposity and higher odds of hypertension, high cholesterol, and diabetes., Conclusions: LCS use is prevalent among South Asians, emphasizing the need for long-term, prospective studies to investigate its role in incident cardiometabolic risk in an already metabolically vulnerable population.

Objective: Few studies examine the relationships between anthropometry and the body composition measures they approximate, or whether they differ by sex, and no studies have examined these relationships in South Asians living in the US., Design: We conducted a cross-sectional study of 871 participants in the Mediators of Atherosclerosis in South Asians Living in America (MASALA) Study who had BMI < 40 kg/m 2 and underwent abdominal CT scans for measurement of visceral and subcutaneous fat. Linear regression was used to model the associations between anthropometric measures and naturally log-transformed body composition measures., Results: All measures of anthropometry, except height, were significantly associated with visceral fat and had a significant non-linear component (p < .05). The only associations for visceral fat that exhibited significant heterogeneity by sex were waist circumference (% difference in visceral fat slope: women 1.92, men 2.74, p = .007 for interaction) and waist-to-hip ratio (women 25.9, men 717.4, p < .001). Except for height, all measures of anthropometry were significantly associated with subcutaneous fat, had a significant quadratic component, and significant heterogeneity by sex (weight (kg): 2.74 for women, 4.08 for men; BMI (kg/m 2 ): 10.3, 14.0; waist circumference (cm): 1.51, 3.36; hip circumference (cm): 2.53, 4.50) with p < .001 for each., Conclusions: In MASALA participants, the relationships of anthropometric measures with visceral and subcutaneous fat appear similar to other race/ethnic groups, but with weaker non-linearity and heterogeneity by sex. Given these results, researchers should consider separate models by sex for US South Asians when approximating subcutaneous fat or when using waist circumference to approximate visceral fat.

Background: The neighborhood built environment can have a strong influence on physical activity levels, particularly walking for transport. In examining racial/ethnic differences in physical activity, one important and understudied group is South Asians. This study aims to describe the association between neighborhood walkability and walking for transport among South Asian men and women in the United States in the Mediators of Atherosclerosis in South Asians Living in America (MASALA) Study., Methods: A cross-sectional study was conducted in 2014 using the baseline dataset of the MASALA study (N = 906). Mean age was 55 years old and 54% of the sample was male. Weekly minutes spent walking for transport was assessed using a questionnaire adapted from the Cross-Cultural Activity Participation Study. Neighborhood walkability was measured using Walk Score, a composite index of walkability., Results: After adjusting for covariates, with each 10-point increase in Walk Score, South Asian American men engaged in 13 additional minutes per week of walking for transport (P = .008). No association was observed between walkability and walking for transport in South Asian American women., Conclusions: Results provide new evidence for how the effects of environmental influences on walking for transport may vary between South Asian men and women.

Background: Individuals from South Asia have high diabetes prevalence despite low body weight. We compared the prevalence of diabetes among South Asian Indians with other U.S. ethnic groups and explored correlates of diabetes., Methods: This was a cross-sectional study of 150 South Asian Indians (ages 45-79) in California, using similar methods to the Multi-Ethnic Study of Atherosclerosis (MESA). Type 2 diabetes was classified by fasting plasma glucose (FPG) >or=126 mg/dL, 2-h postchallenge glucose >or=200 mg/dL, or use of hypoglycemic medication., Results: A total of 29% of Asian Indians had diabetes, 37% had prediabetes, and 34% had normal glucose tolerance. After full adjustment for covariates, Indians still had significantly higher odds of diabetes compared to whites and Latinos, but not significantly different from African Americans and Chinese Americans in MESA: Indians [odds ratio (OR), 1.0], whites [OR, 0.29; 95% confidence interval (CI), 0.17-0.49], Latinos (OR, 0.59; CI, 0.34-1.00) African Americans (OR, 0.77; CI 0.45-1.32), Chinese Americans (OR, 0.78, CI, 0.45-1.32). Variables associated with prediabetes or diabetes among Indians included hypertension, fatty liver, visceral adiposity, microalbuminuria, carotid intima media thickness, and stronger traditional Indian beliefs., Conclusions: Indian immigrants may be more likely to have diabetes than other U.S. ethnic groups, and cultural factors may play a role, suggesting that this is a promising area of research.