A home-based diet and exercise program reduced the rate of functional decline in a study of more than 600 overweight and older cancer survivors, according to a trial involving more than 600 people.
Even modest lifestyle changes elicited by the program produced clinically meaningful improvements in physical function and health-related quality of life for patients who were 5 years or more beyond their cancer diagnosis, said Miriam C. Morey, Ph.D., of Duke University's Center for the Study of Aging and Human Development, Durham, N.C., and her associates.
The researchers conducted a clinical trial in which 319 subjects were randomly assigned to the diet and exercise intervention and 322 were assigned to a control group with no intervention. The study participants were long-term survivors of breast, prostate, and colorectal cancer with no evidence of progressive disease and no additional cancers.
The 1-year intervention was conducted using telephone counseling and materials delivered by mail to the subjects' homes in 21 U.S. states, Canada, and the United Kingdom. The program included a workbook tailored to each participant's needs, with recommendations for strength training (15 minutes daily), endurance training (30 minutes daily), increased intake of fruit and vegetables, restriction of saturated fat, and a goal of a 10% weight loss by the end of the program. It also provided subjects with pedometers, exercise bands for resistance training, guides for exercising and food portioning, and record logs for self-monitoring (JAMA 2009;301:1883–91)
Counseling was conducted during 15 telephone counseling sessions, each 15- to 30-minutes long. There were also eight automated telephone calls during the 12-month period, and participants received quarterly newsletters tailored for each individual to depict his or her progress. There were 50 dropouts in the intervention group and 33 in the control group.
After 1 year, global physical function declined half as much in the intervention group as in the controls—by 2.15 points on the Short-Form 36 physical function subscale in the intervention group and 4.84 points in the controls. A 2-point decline on this scale “is considered too small to be clinically detectable,” while a 6-point decline is associated with higher mortality, said Dr. Morey and her colleagues, who reported no conflicts of interest. Health-related quality of life decreased in every subscale among the controls, but decreases were of lower magnitude in the intervention group.
The proportion of subjects who met recommendations for strength training was 28% with the intervention, compared with 11% among controls. A mean of 15% of the intervention group and 11% of the control group met recommendations for endurance exercise.
Sixteen percent of the intervention group met guidelines for fruit and vegetable intake, compared with 4% of the control group. And the intervention group reported a mean weight loss of 2.06 kg, compared with 0.92 kg for the control group.