Where you live may determine cardiac risk, study shows
Better access to preventative health care associated with lower rates of heart attacks, stroke
Nijaz Hodzic, 55, discovered he was close to having a heart attack about a week ago.
After experiencing chest pain in the middle of February, and delaying a trip to the doctor for a few weeks, he was advised to undergo more tests. Hodzic, who lives in Toronto, ended up in the office of Dr. Jack Tu, a senior scientist at the Institute for Clinical Evaluative Sciences and Sunnybrook’s Schulich Heart Cen- tre, who discovered Hodzic’s right coronary artery was almost completely blocked.
“It was almost non-functional,” Hodzic said. “Another 5 per cent and that would be a very bad heart attack, they told me.”
Where one lives in Ontario could determine one’s risk of a heart attack or stroke, or dying of cardiovascular disease, according to a new study conducted by the Cardiovascular Health in Ambulatory Care Research Team.
Researchers examined data for 5.5 million adults with no previous cardiovascular disease in Ontario between 40 and 79 years of age as of Jan.1, 2008. They looked for heart attacks, strokes or cardiovascu- lar-related deaths over five years.
Hodzic’s blockage was removed on March 27 and he is now home, recovering.
“Everything happened very fast and everything was very organized,” he said. “I didn’t do anything.”
Hodzic avoided a major cardiac event, which the study defines as “hospital admission due to myocardial infarction or stroke, or cardiovascular-related death,” but had he lived somewhere else with less access to basic and advanced preventative health care, his story might have ended differently.
“Our data suggests both basic and advanced preventative care contribute to the lower rates of cardiac events seen in the Toronto area,” Tu said.
Those who lived in parts of Ontario with better access to preventative health care had lower rates of cardiac events compared to residents of regions with less access, according to the study, published in the Canadian Medical Association Journal.
Preventative health care includes “having cholesterol levels checked, being checked for diabetes, being checked for high blood pressure and then, assuming you are diagnosed with having these risk factors, getting optimal management of those risk factors,” said Tu, lead author of the study.
“We’ve known for many years that there are geographical variations in cardiovascular mortality in Ontario, but it was uncertain what was causing it,” Tu said.
“It’s important to understand that health-care factors across the province are contributing to regional disparities.”
According to the study, 74.5 per cent of the regional variation could be accounted for in some way and 15.5 per cent of that variation was found to be the result of “health system factors.”
Ontario’s 14 Local Health Integration Networks were examined and organized into three categories: regions with a low number of cardiovascular events (3.2-3.5 events per 1,000 person-years), a medium number (3.9-4.7 events per 1,000 personyears) and a high number (4.8-5.7 events per 1,000 person-years).
The regions with the lowest number of cardiac events included Toronto Central and Mississauga Halton, while the highest event rates were found in northern Ontario, the North Simcoe Muskoka region and the Erie St. Clair region.
People in low-rate regions visited family doctors more often, were more likely to be screened for heart disease risk factors and had better control of high blood pressure compared with residents of higher event areas, according to the study. They were also more ethnically diverse.
People in high-event regions were more likely to be obese, to smoke and to have the lowest dietary intake of fruits and vegetables. Yet “those who have the highest risk have the least amount of preventative care,” Tu said.
“We think part of the difference is due to the availability and accessibility of primary care in different health regions across Ontario,” Tu said.
“I think part of it’s related to supply. In general, a lot of physicians prefer to live in the Toronto area and generally fewer physicians practise in rural areas of Ontario, paradoxically the areas where the need is the greatest.”
The findings have “important implications for the health-care system,” Tu said.
“Hopefully, people working in the higher-rate areas will be able to use this information to try to come up with plans to reduce the disparity and increase the amount of care for people in high-risk regions.”
Dr. Charles Gardner, the medical officer of health for the Simcoe Muskoka District Health Unit and a member of the Ontario Public Health Association, said the study’s findings were “not surprising.” He said although the15.5-per-cent variation due to health care is important, it’s “more interesting that the bulk of the variation is correlated with what they call cardiac risk factors and with socioeconomic status.”
“We know they are very impactful, more impactful on health than health care,” Gardner said.
“If you really want to make a difference in the health status in these areas, you’re going to have to address those other factors, not just access to health care.”