The Silent Risk: Why South Asians Face a Hidden Epidemic of Heart Disease

Genetics, Underrated Risk Scores, and the Urgent Need for Tailored Prevention

Did you know that the American Heart Association (AHA) and the American College of Cardiology (ACC) guidelines identify just being South Asian is a risk-enhancing factor for atherosclerotic cardiovascular disease (ASCVD)? This designation reflects the elevated risk of heart disease among individuals of South Asian¹ descent—even after accounting for traditional risk factors. Moreover, standard risk assessment tools—such as the Pooled Cohort Equations (PCE)—tend to underestimate cardiovascular risk in South Asians, as they are primarily calibrated for non-Hispanic white and Black populations, according to the NIH. I wish my primary care physician had recognized this limitation. As I detailed in my post on coronary calcium scans, I faced significant resistance in obtaining one because my LDL cholesterol levels fell within the recommended range. However, I persisted—and the scan revealed a coronary artery calcium (CAC) score well over 100, leading to an immediate statin prescription.

Heart disease is the leading cause of death among Asian Indians in the United States, accounting for 28% of deaths in men and 24% in women. The burden is especially severe in younger South Asian populations, with Asian Indians (men under 55 and women under 65) facing significantly higher odds of premature ischemic heart disease compared to other ethnic groups. Notably, Asian Indians are the only racial or ethnic group in the United States experiencing rising mortality rates from ischemic heart disease. Contributing to this trend are early-onset risk factors such as diabetes and hypertension, which often present nearly a decade earlier than in other populations—significantly increasing lifetime cardiovascular risk. As a result, South Asians bear a disproportionately high burden of premature mortality from ASCVD. For example, the proportion of CVD-related deaths classified as premature (under age 70) is significantly higher in South Asian countries, with rates of 59.3% in Pakistan and 50.6% in India, compared to 28.0% in China.

Unfortunately, South Asians seem to have drawn the genetic short straw when it comes to heart health. Their elevated risk of cardiovascular disease stems from a complex mix of genetic factors that impact everything from how the body handles fats and insulin to where it stores fat. For example, variations in the LPA gene lead to higher average levels of lipoprotein(a)—a known risk factor—compared to other ethnic groups. On top of that, South Asians often have a distinctive and unfavorable lipid profile: high triglycerides, low HDL (“good” cholesterol), and more harmful cholesterol particles, even when their LDL levels look normal. Genetic variants in the APOC3 gene, especially one called rs5128, are strongly linked to those high triglyceride levels. And if that weren’t enough, South Asian babies tend to be born with higher insulin and leptin levels despite lower birth weights—a sign of a “thin-fat” body type that’s prone to insulin resistance and metabolic issues right from the start.

The MASALA Study (Mediators of Atherosclerosis in South Asians Living in America) is the first large, longitudinal U.S. study focused on understanding why South Asians have higher rates of heart disease and how to better prevent and treat it. Here are the main conclusions and findings based on recent research:

• High Prevalence of Cardiometabolic Risk Factors: South Asians in the U.S. have a very high prevalence of diabetes, pre-diabetes, and high blood pressure compared to other ethnic groups. These risk factors are driven by metabolic syndrome and insulin resistance, which often emerge at younger ages and lower body mass indices compared to other populations.

• Unique Fat Distribution and Metabolic Risk: South Asians store fat differently, with a tendency for fat to accumulate in the liver and around abdominal organs (visceral fat), which is strongly linked to insulin resistance, diabetes, and cardiovascular disease. Even at normal or low BMI, South Asians may have high levels of harmful fat, explaining why traditional risk measures can underestimate their risk. South Asians also exhibit higher body fat percentages at lower BMI levels compared to Caucasians. This "thin-fat" phenotype² contributes to insulin resistance and dyslipidemia even in non-obese individuals.

• Elevated Lipoprotein(a) and Subclinical Atherosclerosis: South Asians have higher levels of lipoprotein(a) [Lp(a)], a cholesterol particle associated with increased risk of heart disease and stroke³. Coronary artery calcium (CAC), a marker of subclinical atherosclerosis, is higher in South Asians with elevated risk scores, showing that traditional risk calculators may underestimate their true risk.

What are the Clinical Implications?

• Coronary Artery Calcium Scan to detect atherosclerosis is a must for all South Asians, especially the younger adults. If the calcium score is high, ensure that you are on statin medications immediately. Please read my post on Calcium CT scans.

• Aim for Lower LDL-C and Triglyceride Thresholds: Studies show ASCVD appears at lower LDL-C levels in South Asians. For example, the INTERHEART study found that South Asians had heart attacks at LDL-C levels about 10 mg/dL lower than other groups, and a significant proportion of South Asians with heart disease had LDL-C below 100 mg/dL. Triglycerides are also higher in South Asians with heart disease, and the “atherogenic dyslipidemia” phenotype (high triglycerides, low HDL, small dense LDL) is more severe in South Asians than in Europeans. Current guidelines for lipid management in South Asians are mostly extrapolated from Western data. There is a recognized need for lower thresholds, but no large studies have established specific targets for this population. Some researchers suggest using lower LDL-C thresholds for South Asians (e.g., <70 mg/dL for very high-risk individuals) and starting statins earlier.

• Please Modify Carb-Heavy Diets: South Asians too often indulge in diets rich in refined carbohydrates (e.g., white rice, naan, chapati), fried foods and saturated fats (e.g., ghee) which drive postprandial hyperglycemia and dyslipidemia⁴. Compared to Western populations, South Asians also consume less fiber, protein and healthy fats, exacerbating cardiometabolic risks.

• Aim for Lower Waist Circumference Thresholds: Waist circumference is a critical metric for South Asians to combat cardiovascular disease (CVD) because of the previously discussed "thin-fat phenotype" characterized by higher visceral and ectopic fat accumulation at lower body mass indices compared to other ethnicities. Consequently, lower waist circumference thresholds of ≥90 cm for men and ≥80 cm for women (compared to ≥102 cm and ≥88 cm for Europeans) are recommended for South Asians by major organizations including the International Diabetes Federation, and American Heart Association.

Takeaway: South Asians face uniquely high and early risks of heart disease, driven by genetic factors, metabolic differences, and under-recognition in standard medical guidelines. Tools like coronary calcium scans and lower lipid thresholds are essential for early detection. Diet and lifestyle adjustments tailored to South Asian physiology can significantly reduce cardiovascular risk. It’s time for more proactive, personalized prevention.

1. South Asians (from Bangladesh, Bhutan, India, the Maldives, Nepal, Pakistan, and Sri Lanka) make up one quarter of the world’s population and are one of the fastest-growing ethnic groups in the United States.

2. The "thin-fat" or "skinny fat" phenotype describes individuals who have a normal body mass index (BMI) but a high percentage of body fat, often accompanied by reduced muscle mass and strength.

3. Please refer to this post on Lp(a).

4. Dyslipidemia is a condition characterized by abnormal levels of lipids (fats) in the blood. It is an important risk factor for cardiovascular disease.