A new study suggests that the number of overweight and obese cancer survivors in Canada is comparable the general population.
The study concluded that:
- Less than 22 per cent of those who had survived cancer were physically active, compared to 25 percent of Canadians in general.
- About 34 per cent of cancer survivors were found to be overweight, compared to 37 per cent of Canadians in general.
- About 18 per cent of cancer survivors were found to be obese, compared to 15 per cent of Canadians overall.
Dr. Kerry Courneya, lead study author, told CTV's Canada AM on Monday that the results are troubling.
"One of the key points we found is that cancer survivors are no different than the general population in terms of their exercise levels and their obesity rates. And unfortunately that's not a very good thing."
Courneya said that previous studies have shown that physical inactivity and obesity are risk factors for developing cancer and other illnesses.
"What we've found over the last few years with a flurry of studies, is that lifestyle issues are just as important if not more important after a cancer diagnosis," said Courneya.
Courneya cited studies that have analyzed data from survivors of breast and colon cancer.
"What those studies found is that the more active these cancer survivors were after their treatments, the lower the likelihood of their disease coming back and the lower the chance of them dying from the cancer."
Courneya, professor and Canada Research Chair at the University of Alberta in Edmonton and affiliated scientist with the Centre for Behavioural Research and Program Evaluation, said that he believes many patients are not getting enough counselling about the potential effects of a healthy diet and exercise.
"You have to realize at the time of a diagnosis and going through these treatments, the oncologists are focused on the treatment plan, what the cancer patients are going to do," Courneya said.
"Some of them don't necessarily feel qualified to talk to their cancer patients about exercise, or have the time necessarily to try and promote these lifestyle behaviours. So we don't think that cancer survivors are really getting a strong message that it's particularly important for them to maintain a healthy weight and to exercise regularly both during and after their treatments."
The study was published in CANCER, the journal of the American Cancer Society, and supported by the Canadian Cancer Society. The findings were compiled from more than 114,000 Canadian adults who had completed the 2005 Canadian Community Health Survey. The survey asked for details of participants' cancer history, height, weight and physical activity levels.
Interestingly, male cancer survivors were more likely to be overweight or obese than female cancer survivors, but the study found the highest levels of physical activity and the lowest levels of obesity among prostate cancer survivors.
The lowest levels of physical activity were reported among female melanoma survivors, as well as survivors of colorectal and breast cancer.
The findings come shortly after the Canadian Cancer Society released its statistics for cancer incidents in Canada.
That study estimated that there will be 166,400 new cases of cancer diagnosed in Canada in 2008, an increase of 6,500 cases over last year. It was also estimated that 73,800 people would die from cancer this year, an increase of 1,100 over last year.
Abstract:
Physical Activity and Obesity in Canadian Cancer Survivors
Population-Based Estimates From the 2005 Canadian Community Health Survey
Kerry S. Courneya, Peter T. Katzmarzyk, Eric Bacon
BACKGROUND. Physical inactivity and obesity are associated with poorer disease outcomes in several cancer survivor groups. Few studies, however, have provided population-based estimates of these risk factors in cancer survivors and compared them with individuals without a history of cancer. Here such estimates for the Canadian population are reported.
METHODS. Data were obtained from the 2005 Canadian Community Health Survey consisting of computer-assisted interviews of 114,355 adults representing an estimated 23,285,548 Canadians. Participants self-reported their cancer history, height, and body weight to calculate body mass index and participation in various leisure-time activities.
RESULTS. Fewer than 22% of Canadian cancer survivors were physically active and over 18% were obese. Few differences were observed between cancer survivors and those without a history of cancer except that: 1) prostate cancer survivors were more likely to be active (adjusted odds ratio [OR] 5 1.27; 95% confidence interval [CI] 5 1.01-1.59) and less likely to be obese (adjusted OR 5 0.71; 95% CI 5 0.56-0.90); 2) skin cancer survivors (nonmelanoma and melanoma) were more likely to be active (adjusted OR 5 1.33; 95% CI 5 1.12-1.59); and 3) obese breast cancer survivors were less likely to be active compared with obese women without a history of cancer (adjusted OR 5 0.51; 95% CI 5 0.27-0.94).
CONCLUSIONS. Canadian cancer survivors have low levels of physical activity and a high prevalence of obesity that, although comparable to the general population, may place them at higher risk for poorer disease outcomes. Population-based interventions to increase physical activity and promote a healthy body weight in Canadian cancer survivors are warranted.
