By Nicole Zhao ’20

Heart disease is the leading cause of death for both men and women worldwide. However, people of South Asian descent have a higher death rate from heart disease than any other group. Following a variety of diets, from omnivorous to vegetarian, South Asians are four times more likely to be diagnosed with heart disease even at normal body weight and tend to develop the pathology up to a decade earlier compared to the general population.

A joint research project between the University of California, San Francisco, and Northwestern University known as MASALA (The Mediators of Atherosclerosis in South Asians Living in America) aims to shed light on risk factors that cause the disease. In a recent study, they found that the incidence and progression of coronary artery calcium in South Asians were highest when compared to four race/ethnic groups. Coronary artery calcification (CAC) is a condition characterized by hardened blood vessels, which restricts blood flood and increases the likelihood of a heart attack or stroke; CAC is a marker of atherosclerosis.

In this study, a total of 698 South Asian participants were monitored for about five years and their coronary artery calcium levels were periodically scored via CT scans. It was found that the median annual CAC progression was 26 for men and 13 for women. The CAC score thresholds were defined for risk prediction ranging from very low to very high-risk events (CAC 0; 1-100; 101-400; and >400). Therefore, an annual increase of 26 in one’s CAC score could substantially increase one’s risk for a cardiovascular event over their lifetime.

Comparing these results with MESA, the Multi-Ethnic Study of Atherosclerosis, CAC incidence was similar in South Asian men and white, black, Latino men, but was significantly higher than in Chinese men. Moreover, it was found that diabetes, hypertension, and statin medication use, which is used to lower cholesterol levels, was higher in South Asian and white men. South Asian women’s calcium artery levels had no significant differences when compared to women of other races. This study is indubitably important as it reveals disparities in heart disease risk among races, which should be taken into account when determining cardiovascular disease risk and treatment options.
References

1. A. Kanaya, et. al., Incidence and progression of coronary artery calcium in South
   Asians compared with 4 race/ethnic groups. Journal of American Heart Association 8, (2019). doi: 10.1161/JAHA.118.011053.  
2. Image retrieved from: https://www.pexels.com/photo/bright-cardiac-cardiology-care-433267/