Higher risk of heart disease for South Asians in Canada

The paper was published today in the Canadian Medical Association Journal (CMAJ Open).

One of the fastest-growing ethnic groups in the country is the more than one million South Asian people living in Canada, comprising about three percent of the population. They include people from India, Pakistan, Sri Lanka, Nepal and Bangladesh.

To understand the risk of heart disease in this population, researchers looked at data from 50 studies conducted in Canada between 1979 and 2007 that included more than 5.8 million people. Collectively, these studies show that people of South Asian background have a higher prevalence of heart disease (a history of myocardial infarction, angina, coronary artery bypass grafting or stroke) compared with white people (5.7% to 10% for the former and 5.4% to 5.7% for the latter). Rates of death from coronary artery disease were also higher: 42% for South Asian men compared with 29% of white men and 29% versus 19% for women. South Asian people are also more likely to have diabetes and hypertension than white people.

Even when the authors compared South Asians to white people of the same body size, South Asians had higher percentages of body fat and more abdominal fat, and South Asian women had a higher waist-to-hip ratio, which are all key risk factors for heart disease. However, South Asians were less likely to be obese (BMI ³ 30) and 60% less likely to smoke than white Canadians.

"[Our findings emphasize] the need to develop a standardized surveillance system for non-communicable diseases, such as CVD, cancer and lung diseases, by ethnic group in Canada," writes Sonia Anand, professor of medicine of the Michael G. DeGroote School of Medicine, McMaster University, with coauthors. "Such a system would generate information that would help shape health services, policies and programs aimed at particularly high-risk ethnic groups."

"Given the increased prevalence and mortality associated with CVD among South Asian people living in Canada, etiologic studies to understand the development of these risk factors among children and youth and intervention strategies to reduce risk factors and CVD among this high-risk group are needed," said coauthor Scott Lear of Simon Fraser University.