Studies continue to show increased risk of cancer recurrence and death in obese individuals, but new research highlights the benefits of weight loss interventions for overweight and obese cancer survivors.
Overweight and obese survivors who participated in a 15-week weight loss program lost 5.3 percent of their baseline weight and had significant improvements in physical fitness and functioning, according to a randomized trial presented by Rachel L. Yung, at the 2016 Cancer Survivorship Symposium in San Francisco.
“There have been few weight loss interventions tested in cancer patients, especially in malignancies other than breast,” said Yung, Dana-Farber Cancer Institute, instructor of medicine, Harvard Medical School.
“There’s also a lack of financial support for these interventions.”
For the study, 30 patients were enrolled and randomized to immediately participate in a 15-week healthy living program implemented through an oncology clinic. Another 30 patients underwent a 15-week control period with delayed participation in the program.
Nearly all of the participants in both groups were women (97 percent) with a median age of 52. The average body mass index (BMI) was about 32 kg/m2 and 80 percent of the patients had breast cancer.
Led by health coaches and exercise physiologists, the healthy living program focused on reducing calories by between 500 and 1000 calories per day and engaging in 150 minutes of moderate to intense exercise per week. Patients made individualized weekly diet and exercise goals for themselves.
The primary objective was to examine weight loss, but the researchers also looked at the program’s effect on physical fitness, physical activity, physical functioning, body composition and patient-reported outcomes, including fatigue, sleep patterns and body image.
After 15 weeks, survivors in the intervention group had a weight loss of 4.6 kg (about 10 lbs), compared to a weight gain of 0.2 kg (about 0.5 lbs) in the control group. Majority of the weight lost was fat mass.
Participants who completed the weight loss program also had an increase of 74 feet that they were able to walk in the six-minute walk test to determine baseline physical fitness. In addition, patients in the intervention group were about to maintain their high baseline scores for physical functioning, but those in the control group had a reduction in their scores over the 15-week period.
Although not statistically significant, there was also improvement in patient-reported fatigue and sleep patterns.
Yung noted that previous studies have shown that weight loss of at least 4 kg (about 9 lbs) has been shown to have clinically meaningful implications in terms of general health benefits.
Since at least 2003, she said, “the research has increased showing a dramatic relationship between obesity and cancer — both developing cancer and cancer morbidity.”
She added that particular barriers can make lifestyle changes difficult for cancer survivors to accomplish.
Both providers and survivors are sometimes unaware of the link between cancer and obesity, Yung said. However, even if there is awareness of the correlation, survivors may experience residual adverse effects from their cancer therapy that prevent them from physical activity.
In addition, there is also a lack of financial support and access to effective intervention programs, Yung said.
The authors concluded that more research is needed to examine the feasibility and sustainability of such weight loss programs, but said that these findings can serve as preliminary information for similar interventions in oncology practices.
Yung RL, Giobbie-Hurder A, Shockro L, et al. A randomized trial of a clinic-based weight loss intervention in cancer survivors. Presented at: Cancer Survivorship Symposium; January 15-16, 2016; San Francisco, CA. Abstract 167.