Why these heart attacks occur is only partially answered with traditional risk factor assessment. South Asians tend to be smokers, and the typical South Asian diet tends to be high in sugar, refined grains, and fatty foods.
An alarmingly high number of South Asians appear to be insulin resistant, a pre-diabetic condition in which the body does not process insulin efficiently. Insulin-resistant patients have similar rates of cardiovascular events as those with full-blown diabetes.
Body mass index (BMI) in South Asians often falls into a thin-fat syndrome: People may have an acceptable BMI, but they also carry more of their weight in their abdomen and that visceral fat is more likely to lead to a cardiovascular event.
More than one-third of South Asian men and 17% of South Asian women have metabolic syndrome. Metabolic syndrome is a cluster of conditions including:
- High blood pressure
- High blood sugar levels
- Excess body fat around the waist
- Abnormal cholesterol levels that increase the risk of heart disease, stroke and diabetes
If more than one of these conditions occur in combination, the risk is even greater. South Asians are more likely to have high triglycerides and low HDL (the good cholesterol).
A variant of HDL known as HDL2b, which is thought to mediate the good effects of HDL, is low in as many as 93% of South Asian men and 63% of women.
What compounds these risks in the South Asian population is a lack of specific testing: The criteria for metabolic syndrome and the subfractionation of HDL and other lipid- and inflammatory-based cardiovascular risk biomarkers are typically not checked during routine physical exams and they are often overlooked in a standard cardiovascular workup.
The cardiovascular risk in South Asians appears to begin early: Research has shown that even in infancy, children of South Asian heritage may have high levels of cholesterol and lipoproteins in their blood.