Clinical risk factors for atherosclerotic cardiovascular disease (ASCVD) are higher in midlife among South Asian adults in the US than other racial and ethnic groups, data from a long term study show. The new findings, the authors say, help to explain high rates of coronary heart disease in this demographic group and argue for earlier, more tailored care for people with South Asian ancestry.
“An important clinical implication is that those of South Asia origins, regardless of contemporary living location, should have early screening and management of CVD risk factors,” said Daniel W. Jones, MD, a past president of the American Heart Association (AHA) who was not involved with the study.
The Background
People from South Asia a region that includes Bangladesh, Bhutan, India, Maldives, Nepal, Pakistan, and Sri Lanka have an elevated ASCVD risk compared with other groups, and cardiac events also tend to strike South Asian individuals earlier.
The difference is so pronounced that in 2018, the AHA and the American College of Cardiology (ACC) added South Asian ancestry as a risk-enhancing factor in their cholesterol management guidelines for people with intermediate ASCVD risk.
Back in 2010, researchers at the University of California San Francisco and Northwestern University in Chicago began the Mediators of Atherosclerosis in South Asians Living in America, or MASALA, study.
The National Institutes of Health funded prospective cohort study aims to better understand the heightened heart disease risk in this community.
Why This Matters
South Asian people represent a quarter of the global population and number 6.4 million in the US, where they are a growing ethnic group.
Although it’s widely known that ASCVD is more common and appears earlier in the US South Asian population than the White population, the new study’s authors say there’s less information on the prevalence and emergence of risk factors that contribute to the disease in different US groups. Teasing apart “risk trajectories” for various populations could enable “tailored prevention strategies across the life course,” they wrote in the Journal of the American Heart Association in February. This is important for all groups, they say, but particularly for those at high risk.
The Methods
The researchers combined harmonized data from more than 500 participants in MASALA, which included adults of Bangladeshi, Indian, and Pakistani ancestry in the US, and more than 2000 participants in its sister study, the Multi-Ethnic Study of Atherosclerosis, or MESA, which included Black, Chinese, Hispanic, and White adults in the US. They compared the prevalence of clinical and behavioral ASCVD risk factors in middle age across racial and ethnic groups and then further analyzed by gender.
The Findings at Age 45
“Our question was, do South Asians develop more heart disease risk factors at a younger age than other groups?” said Namratha Kandula, MD, MPH, a co principal investigator on the MASALA study. “And we did find in fact that by age 45, South Asians do seem to have a higher prevalence of prediabetes and the second highest prevalence of hypertension despite having healthier diets and doing as much exercise and drinking moderate amounts of alcohol and very low tobacco use.”
What the study found:
- Prediabetes: Both South Asian men and women had much higher rates of prediabetes than all other groups. About 31% of South Asian men and 18% of South Asian women had prediabetes, compared with only 4% of White men and 6% of White women.
- Hypertension: South Asian men and women also had higher rates of hypertension than all other groups except Black men and women. About 25% to 30% of South Asian and Black participants had hypertension, whereas only 7% to 8% of Chinese participants did.
- Dyslipidemia: About 78% of South Asian men and 54% of South Asian women had abnormal blood lipid levels. Most men in all racial and ethnic groups had dyslipidemia, but it was more common in South Asian men as well as Hispanic and White men. The same racial and ethnic patterns held true for women.
- Body mass index (BMI): South Asian men had lower BMI on average than Black, Hispanic, and White men. And South Asian women had lower BMI on average than Black and Hispanic women.
- Behavioral risks: On average, South Asian men and women had the best diet scores, the lowest prevalence of smoking, and among the lowest prevalence of alcohol use across racial and ethnic groups. And they were as likely to exercise as most other groups.
- Trends over time: Between ages 45 and 55 years, the prevalence of clinical risk factors increased for all racial and ethnic groups, despite improvements in diet scores and exercise. At age 55 years, South Asian men and women were significantly more likely to have diabetes than White men and women.
The Missing Factors
Kandula, who is a professor of medicine and preventive medicine at Northwestern, said she was surprised to see the contrast between healthful behaviors and the high prevalence of clinical risk factors in the South Asian participants. “Often you hear: ‘Well, of course they have more diabetes. It’s because of their diets.’ or ‘It’s because they’re not doing any exercise.’ And that actually wasn’t true.” The mismatch, she said, begs the question: “What are we missing or what are we not measuring?”
Nilay Shah, MD, MPH, a coauthor of the study and an investigator on both MASALA and MESA, noted that sedentary time was not included in the analysis and may be an important additional risk factor. He also acknowledged that dietary assessments using food frequency questionnaires are “imperfect tools.”
But there could be several other missing factors. The analysis included BMI but didn’t account for important differences in body composition and fat distribution that may be present even at a normal BMI. According to Kandula, prior research from MASALA and other studies has shown that South Asian people tend to have less lean muscle mass and often store more fat around the organs and in the liver.
“Whether the South Asian community is enriched in genetic variants that puts them at risk for this or whether there are other behavioral or environmental exposures that are leading to these differences in body composition I think are important areas of future research,” said Shah, who is an assistant professor of cardiology, preventive medicine, and medical social sciences at Northwestern.
These differences matter, Kandula explained, because internal fat around the organs is metabolically active and is associated with more cardiometabolic disease.
The researchers also pointed to the potential role of unmeasured early life experiences. Nearly all MASALA participants are first-generation immigrants who may have had different diets, physical activity levels, stressors, and environmental exposures in the decades before they joined the study, which enrolled people in their 40s and older. A recent joint statement from 4 global cardiology societies the AHA, the ACC, the European Society of Cardiology, and the World Heart Federation acknowledged the underappreciated role of environmental risk factors such as air pollution in cardiovascular disease.
Pregnancy health, which can contribute to future cardiometabolic risk, could be another key risk factor among South Asian people. Shah and colleagues recently found that Asian individuals in the US had the second highest rates of gestational diabetes of any racial and ethnic group, after American Indian or Alaska Native individuals, and that this was largely driven by affected pregnancies in the Asian Indian group.
The Clinical Takeaways
Jones, who is an emeritus professor of medicine at the University of Mississippi Medical Center, said the study adds to the understanding that South Asian people experience ASCVD at an earlier age than other groups. The most important new finding, he said, is the presence of traditional cardiovascular disease risk factors at younger age than other groups, and its predictability.
That means earlier attention must be paid, he and others say.“What we learned is that this is the community for which a conversation about cardiovascular prevention is particularly important early,” Shah said.
The urgency only appears to be growing. In 2022, Shah launched the MASALA Second Generation Study, which is following up the young adult children of the original MASALA participants. In this mostly US-born cohort in their 30s, about two-thirds have a BMI of 23 or greater (a threshold considered clinically elevated for Asian American people by multiple guidelines), about half have dyslipidemia, and about one-fifth report electronic cigarette use.
Kandula was unequivocal in her advice: “South Asians should be screened for cardiovascular risk factors regardless of BMI starting well before middle age.” In her view, this should include screening for elevated lipoprotein A, or Lp(a), levels, which are a strong risk factor for cardiovascular disease and are present in many South Asian individuals. Although there is currently no treatment for elevated Lp(a), knowing a patient’s status can help inform a shared decision about medication initiation, she explained.
Cardiologist Karol Watson, MD, PhD, a co–principal investigator of the MESA study who wasn’t involved with the new analysis, also said that patients with South Asian ancestry should be screened much earlier for cardiovascular disease risk factors, regardless of their BMI or diabetes status.
“Don’t think only about the typical sort of obese-diabetic phenotype that we mostly see in this country,” she said, adding that the University of California Los Angeles preventive cardiology program, which she codirects, starts screening South Asian patients at 18 years. “I can tell you the number of young nonobese South Asian patients with disease that I see; it’s striking.”
In an email, Jones agreed with the need for earlier screening for South Asian individuals and advocated for clinical trials to test whether treating their risk factors early improves outcomes.
The Broader Implications
Watson noted that Black participants have the highest cardiovascular risk in the MESA studies, “and that persists whether you control for every single known cardiovascular risk factor, social determinants of health, etc.” Meanwhile, the MASALA and MESA study participants are “more health aware and more health interested” than the general population, she said, which suggests that the larger communities may have worse risk factors. As it stands, the overall prevalence of ASCVD risk factors in all groups by midlife in the current analysis speaks to the importance of counseling patients to pay attention to their cardiovascular health at a much younger age, the researchers say.
“We are letting people get too far down the line in cardiovascular disease risk and we are starting the conversations too late,” Shah said.
It isn’t all on clinicians, though. Shah also noted a critical need for health system–level interventions that keep patients engaged in preventive care during the transition from adolescence to adulthood, when most people disconnect from health care for a time. “This warm handoff between pediatrics care into young adulthood would really help facilitate a conversation about maintaining one’s cardiovascular health.”
Article Information
Published Online: March 13, 2026. doi:10.1001/jama.2026.1798
Conflict of Interest Disclosures: Dr Kandula reported that the MASALA study was supported by grants R01HL093009 and R01HL120725 from the National Heart, Lung, and Blood Institute (NHLBI). She also reported receiving grant K24HL155897 from the NHLBI during the conduct of the study and an honorarium from the Patient-Centered Outcomes Research Institute outside the study discussed in this article, receiving compensation from the American Diabetes Association as an associate editor for Diabetes Care, and serving on the advisory board for the National Council of Asian Pacific Islander Physicians. Dr Shah reported receiving grant funding from the NHLBI (K23HL157766) and the AHA (24CDA1266732). No other disclosures were reported.
