Cancer death rates increased in many countries as unemployment rose during the global economic crisis but universal health coverage provided a buffer, according to a large international study that includes Canadian data.

Cancer is a leading cause of death worldwide, which makes it important to understand how economic changes affect cancer survival.

To find out, Dr. Rifat Atun, a professor of global health systems at Harvard Chan School in Boston, and his team analyzed the link between unemployment, public health-care spending, and cancer mortality using data from 1990-2010 from more than 70 high- and middle-income countries around the world, representing roughly two billion people.

After comparing estimates of expected cancer deaths with actual deaths from cancer during the 2008 to 2010 recession, they found that the downturn was linked with more than 260,000 excess cancer deaths among countries in the Organization for Economic Co-operation and Development (OECD) alone, Atun and his team said in Wednesday's online issue of The Lancet.

"This is the first time this has been shown for cancer," Atun said.

"The message is very clear. Unemployment does lead to excess number of cancer deaths but if there's strong health systems and if public health expenditure increases, many of these cancer deaths can be reduced."

A one per cent increase in unemployment was associated with 0.37 additional deaths from all cancers per 100,000 people.

The association disappeared when universal health care was taken into account.

'Value for money and value for many'

The researchers from Harvard, and Oxford University, Imperial College London and King's College London in the U.K. looked at prostate cancer in men, breast cancer in women, colorectal cancer in men and women and lung cancer in men and women.

The cancers were classified as treatable for those with five-year survival rates over 50 per cent or untreatable for those with survival rates of less than 10 per cent.

Atun suggested governments "ensure value for money and value for many" by ensuring universal health coverage is truly universal and equitable for vulnerable populations.

The study was not experimental and can't prove cause and effect but the timing of how changes in unemployment was followed by changes in cancer mortality lends support to a causal link, the authors said.

Access to health care

Dr. Andrew Pinto is a clinician-scientist at St. Michael's Hospital in Toronto who was not involved in the research. He's impressed with the robustness of the finding and its consistency across different countries.

"This fits with other information that we have about how precarious work is linked to people's health," Pinto said. "The way that works is sudden job loss leads to people not having enough income. In some countries, it also means they lose access to health-care services."

Pinto believes in times of economic crisis, governments should redouble their efforts for people who are economically disadvantaged.

"This teaches us a lesson about the link between economic crises and health outcomes but also how governments choose to respond. For future crises that happen, the public and the average Canadian should maybe question turning to austerity as a response."