A randomized clinical trial examining the effect of a 15-week healthy living program on weight loss in cancer survivors showed a 5.3% decrease in baseline body weight in those participating in the program.1
“Cancer survivors randomized to a 15-week clinic-based weight-loss intervention lost an average of 4.6 kilograms,” said Rachel L. Yung, MD, a physician at the Dana-Farber Cancer Institute, Boston, and Instructor in Medicine at Harvard Medical School. “Intervention participants also experienced significant increases in physical functioning compared to the control group.”
Correlation Between Cancer and Obesity
As Dr. Yung reported at the 2016 Cancer Survivorship Symposium, there has been a rapid and dramatic rise in obesity in the United States in the past 25 years. In addition, observational studies have consistently shown an increased risk of cancer death and cancer morbidity in obese individuals.2 And yet barriers to lifestyle change in cancer survivors include a lack of awareness between cancer and obesity and/or inactivity.
“Even when we do have awareness of the correlation,” said Dr. Yung, “losing weight and increasing exercise are challenging, especially for survivors, who often have residual side effects and symptoms from their therapy.”
“There’s also a lack of access to effective programs,” she added. “There have been few weight-loss interventions tested in cancer patients…, and there’s a lack of financial support for these interventions.”
Healthy Living Program
Dr. Yung and colleagues randomized 60 patients with a diagnosis of invasive cancer either to immediate participation in a 15-week weight loss program or a control period with delayed participation. The goals of the program were a 15-week weight loss of 5% to 7% achieved through caloric reduction and exercise.
“This was a weekly group-based session led by health coaches and exercise physiologists,” Dr. Yung explained. “It was supplemented by workbook material and an activity sensor, and personalized weekly diet and exercise goals were made for each of the participants.”
Weight Loss in Cancer Survivors
- Cancer survivors randomized to a 15-week clinic-based weight-loss intervention lost an average of 4.6 kilograms.
- Intervention participants also experienced significant increases in self-reported and objective physical functioning.
Patients were eligible if they had a cancer diagnosis and body mass index greater than 25 kg/m2 and had completed all chemotherapy, surgery, and radiation therapy at least 1 month prior to enrollment. Patients were excluded if they had a recent stroke or heart disease, bariatric surgery within the past year, or serious gastrointestinal issues that precluded adherence to the study diet.
Although there were other survivors in the group, participants were predominantly female, breast cancer patients, said Dr. Yung. The average age of the cohort was 52 years, and the average body mass index was 32 kg/m2. It was also a fairly active group at baseline, Dr. Yung noted, with an average of 130 minutes of moderate activity per week.
Weight Loss and Improved Physical Functioning
On average, participants in the intervention group experienced weight loss of 4.6 kg, whereas the control group had weight gain of 0.2 kg. Further analysis of body composition showed the majority of weight lost to be fat mass, with a smaller proportion being lean mass. “Weight loss of greater than 4 kg has been shown to be clinically meaningful in terms of health benefits,” Dr. Yung observed.
Although measures of physical activity were not statistically significant, according to Dr. Yung, there was a suggestion of increase in “steps per day” in the intervention group. “At baseline,” said Dr. Yung, “intervention and control groups were getting approximately 6,500 steps daily. This increased by 1,400 steps in the intervention group and decreased by 700 steps in the control group.”
In terms of physical functioning, however, both measures were statistically significant. In a 6-minute test, participants in the intervention group walked 74 additional feet compared with the control group. Additionally, on the European Organization for Research and Treatment of Cancer physical functioning scale, the intervention group maintained their baseline assessment, whereas the control group showed a decline in physical functioning.
There was also a suggestion of improved fatigue and sleep scales within the intervention group compared with the control, said Dr. Yung, although not quite statistically significant.
“This study provides valuable insights into the development of weight-loss interventions that can be implemented in oncology settings,” Dr. Yung concluded.■
Disclosure: Dr. Yung reported no potential conflicts of interest.
References
1. Yung RL, Giobbie-Hurder A, Shockro L, et al: A randomized clinical trial of a clinic-based weight loss intervention in cancer survivors. 2016 Cancer Survivorship Symposium. Abstract 167. Presented January 16, 2016.
2. Calle EE, Rodriguez C, Walker-Thurmond K, et al: Overweight, obesity, and mortality from cancer in a prospectively studied cohort of U.S. adults. N Engl J Med 348:1625-1638, 2003.
