Lung cancer kills more Canadian women than in 'peer' countries

It's not clear why non-smoking women are at twice the risk of developing lung cancer as non-smoking men, says Dr. Natasha Leighl.

Lung cancer death rates in Canada are among the highest in the world, especially among women, a new report shows. Thursday's report from the Canadian Institute for Health Information (CIHI) uses international health-care data from the Organization for Economic Co-operation and Development. The OECD includes 34 countries and CIHI compares the performance of Canada's health system with what it calls its "peers" — Australia, France, Germany, the Netherlands, New Zealand, Sweden, the United States and the United Kingdom.

The report's authors focused on lung cancer, noting that at 58 deaths per 100,000 population, lung cancer mortality in Canada is higher than the OECD average of 43 per 100,000. All other peer countries had fewer lung cancer deaths than Canada, except for The Netherlands which had the same rate. More people die from lung cancer than from prostate, breast and colorectal cancers combined. In 2009, lung cancer was responsible for 19,110 deaths or eight per cent of Canada's mortality, according to Statistics Canada. By gender, Canada's lung cancer mortality rate among women in 2012 was 47.0 per 100,000 compared with the OECD average of 26.5 per 100,000. In men, Canada's rate was 72.3 per 100,000 versus 66.3 per 100,000. "If we look back over the last 30 years, Canada's smoking rate among men has been consistently lower than the OECD's, while for women the smoking rate was at times higher than OECD average," the report's authors said. "This may help explain why Canada's results for lung cancer mortality in men ranks better than its results for women."

Dr. Natasha Leighl, a medical oncologist at Toronto's Princess Margaret Cancer Centre, said she's seeing a rising proportion of people who've never smoked that are diagnosed with lung cancer.

"We know that non-smoking women are at twice the risk of developing lung cancer as non- smoking men and we really just don't understand why that is," Leighl said. "We've talked about environmental risks as well as things like air pollution, things like radon, but there may even be some genetic differences." For many other health indicators, CIHI's researchers said Canada's results were within the band of average performers between the 25th and 75th percentiles. Canada performed will on indicators such as potentially avoidable hospital admissions for diabetes and asthma. Canada rated high on the OECD's measure of the percentage of people who eat at least a serving of fruit or vegetables per day. But Canada's Food Guide recommends eating seven to eight servings of fruits and veggies daily, meaning it is possible Canadians aren't eating enough to improve the quality of their diet, CIHI's authors said.

Canada also performed well on breast cancer screening and breast cancer survival, which the researchers said could be due to early detection and effective treatment.

Patient safety is an area where Canada performed poorly. Most peer countries except New Zealand and Australia outperformed Canada on leaving behind foreign bodies, like sponges, after surgery. Adopting the Surgical Safety Checklist, which reminds operating room staff to do a final count of equipment like sponges and instruments, has been recommended for all operating rooms.

CIHI's authors called post-operative pulmonary embolism and deep vein thromboembolism — serious blood clots — in hip and knee replacements especially important given that rates of the joint replacements are on the rise. Canada's rate, 888 per 100,000 discharges, for the common and preventable complication was the third-highest among OECD countries, where the average was 541 per 100,000. Canada performed slightly below the OECD average on four patient experience indicators. For example, 81 per cent of Canadians said that their doctor spent enough time in consultation with them, compared with OECD average of 87 per cent.