Among people on the bottom one third of the socioeconomic ladder, Canadians were about 35% more likely to survive cancer than similar US residents, researchers report.
"There seems to be a significant Canadian survival advantage," the study's lead author, Dr. Kevin M. Gorey, of University of Windsor in Ontario, told Reuters Health in an interview.
Differences in the Canadian and US healthcare systems probably account for the better survival odds among Canada's poorer residents, Gorey and his colleagues report in the Journal of Public Health Medicine.
Unlike the US, with its variety of private and government health-insurance programs that leaves many residents falling through the gaps, Canada has a universal healthcare program that provides care to all residents.
With some people in Canada calling for changing the nation's healthcare system to make it more like the American model and some in the US hoping to make healthcare universal as it is in Canada, comparing the two systems is of interest to residents on both sides of the border, according to Gorey. He noted that several previous studies have failed to detect a difference in cancer survival between the two countries, but the research did not break down the statistics by socioeconomic status.
In an earlier study, Gorey and his colleagues did find that economically disadvantaged people in Toronto were more likely to survive cancer than poor Detroit residents. But some people, claiming that Detroit and Toronto were too different to compare, questioned the importance of these findings, Gorey noted.
For the present study, the investigators compared the 5-year cancer survival rates in Toronto and in three relatively well-off American cities: San Francisco, California; Seattle, Washington; and Hartford, Connecticut. Overall, middle- and high-income residents in the US were just as likely to survive the 15 most common types of cancer as their Canadian peers.
But Canada's lower-income residents had a significant advantage over America's poor in nearly all types of cancer, the authors report. And the difference did not appear to be caused by racial differences. When the analysis was limited to poor whites in the US, Canadians still had an advantage (Canadian statistics were not broken down by race).
The disparity between the US and Canada was even greater when the analysis only included people who were diagnosed with cancer before age 65. In the US, most of these people would not be eligible for Medicare, the federal health insurance program for the elderly.
Although the study divided the population into thirds based on socioeconomic status, the researchers suggest that part of the problem may be that people in the US who have low incomes, but who are not poor enough to qualify for Medicaid, are at greater risk of not having health insurance.
But Gorey noted that as is often the case with healthcare records, the present study may not represent today's healthcare situation in the US and Canada, since there is a lag before statistics are made available. In 1995, there was a shift in the funding of the healthcare system in Canada, with more of the burden being placed upon the provinces rather than the federal government, so the situation in Canada may have changed somewhat, he explained.