Associations between lifestyle factors and quality of life among older, long-term breast, prostate, and colorectal cancer survivors

A new study finds that most older long-term cancer survivors who are interested in diet and exercise actually have poor health habits.

The study also reveals that those survivors who do exercise and watch their diet have improved physical health and quality of life. Published in the September 1, 2009 issue of Cancer, a peer-reviewed journal of the American Cancer Society, the research indicates that greater efforts are needed to encourage elderly cancer survivors to live healthier lives.

More than half of the estimated 11 million cancer survivors in the United States are aged 65 years or older. There are relatively few studies looking at older cancer survivors' health behaviors, but evidence suggests that many older long-term cancer survivors have suboptimal health habits.

Catherine Mosher, Ph.D., of the Memorial Sloan-Kettering Cancer Center in New York City and colleagues reviewed data from a total of 753 older (aged 65 years or over), long-term (five or more years post-diagnosis) breast, prostate, and colorectal cancer survivors to estimate the prevalence of poor health habits in this population. Participants were recruited through the North Carolina Central Cancer Registry, the Duke Cancer Registry, and self-referral. The study included telephone interviews to determine individuals' eligibility for a diet and exercise intervention trial. Interviews assessed exercise, diet, weight, and quality of life, including physical functioning and mental health.

The researchers found that older cancer survivors, all of whom were interested in a diet and exercise intervention study, generally had poor health habits. For example, they reported an average of only 10 minutes of moderate-to-vigorous exercise per week. This is far short of the national recommendation of more than 150 minutes of exercise per week. Also, only 7 percent met healthful eating recommendations set by national guidelines. Despite their suboptimal health behaviors, cancer survivors reported a level of mental and physical quality of life that actually exceeded levels typically found among older individuals. This may be explained in part by the study's design: investigators excluded survivors with significant health problems and functional limitations.

The study also found that interviewees who exercised more and had better dietary habits experienced better vitality and physical functioning. On the other hand, individuals who were obese had worse physical quality of life.

"Our findings point to the potential negative impact of obesity and the positive effect of regular exercise and a healthy diet on physical quality of life outcomes among older, long-term cancer survivors," said Dr. Mosher. "Only randomized clinical trials, however, can reveal whether lifestyle modification improves older, long-term cancer survivors' physical outcomes," she added.