It is widely known that rates of obesity, type 2 diabetes and high blood pressure are on the rise. But a new Canadian study shows that certain ethnic groups – specifically, South Asian men and black men and women – get these chronic health problems more often than the rest of the population.
The study, published on Monday in the journal BMJ Open, found that overall, the heart health of South Asian men and black people in Canada has deteriorated significantly in the past decade. For instance, diabetes in South Asian men has doubled to more than 15 per cent of the population in 2012 from 6.7 per cent in 2001.
Among black women, the rate of diabetes grew to just over 12 per cent from 6.3 per cent during that same time period. Rates of obesity rose in each of the ethnic groups studied, but the largest increases were found in black and Chinese men. Given that obesity is often a precursor to chronic health problems, these findings should be sounding an alarm, said Dr. Maria Chiu, scientist at Toronto's Institute for Clinical Evaluative Sciences and lead author of the study.
The obesity trends "paint a really scary picture" of what could happen to type 2 diabetes rates in the future, she said.
The study looked at data from nearly 220,000 Canadians who took part in Statistics Canada's Canadian Community Health Survey. The researchers focused on individuals belonging to Canada's four major ethnic groups: white, South Asian, Chinese and black.
The results add to a growing body of evidence suggesting health problems affect ethnic groups at different rates. While genes certainly play a role, they do not tell the entire story, Chiu said.
"I like to think of it as genes load up the gun and environment pulls the trigger," she said.
Her study helps explain why some ethnic groups appear to be more vulnerable to certain health conditions. Overall, the ethnic minority groups included in the study had household incomes that were as much as $30,000 lower than those of their white counterparts.
Those groups also reported that they ate fewer fruits and vegetables. At the same time, smoking rates among all of the groups studied fell, with the exception of black women and Chinese men.
"This is another wakeup call," said Dr. Sonia Anand, professor of medicine and epidemiology at McMaster University in Hamilton and a spokeswoman for the Heart and Stroke Foundation. "We have to get going or we're going to end up with an epidemic of obesity and type 2 diabetes in the next 20 years."
Anand was not involved in this study, but much of her research focuses on the causes of heart disease in ethnic groups. She said the evidence is clear the differences exist, but there is no clear strategy on how to solve this complex problem.
The important question for researchers and policy makers, according to Chiu, is how to bridge the gap and reverse the trends.
One solution will be to tailor campaigns to ethnic groups, Chiu said. They need to know they are at risk and what changes they can make to reduce their vulnerability, such as quitting smoking or eating more fruits and vegetables.
And, as Anand noted, "we move less, we commute by car, we don't live in walkable neighbourhoods."
That means the necessary solutions are going to require a lot of time, co-ordination, funding and commitment, she said.