Obese women who have breast cancer generally have a worse prognosis compared with their non-obese counterparts. A new randomized study suggests that telephone-based intervention is a safe way to help overweight postmenopausal breast cancer patients with weight loss.
Obese women who have breast cancer generally have a worse prognosis compared with their non-obese counterparts. Observational studies have shown that women who gain weight following a breast cancer diagnosis also have a worse prognosis. It is unclear whether overweight breast cancer patients can overcome some of the negative effects if they lose extra weight during their disease. A new randomized study suggests that telephone-based intervention is a safe way to help overweight postmenopausal breast cancer patients with weight loss. The study was published in the Journal of Clinical Oncology.
Pamela J. Goodwin, MD, of Lunenfeld-Tanenbaum Research Institute and Princess Margaret Cancer Centre in Toronto, Kathleen I. Pritchard, MD, of Sunnybrook Hospital’s Odette Cancer Centre in Toronto, and colleagues conducted the Lifestyle Intervention Study in Adjuvant Treatment of Early Breast Cancer (LISA) to test whether a telephone-based weight loss intervention that included diet and physical activity would have an effect on disease-free survival (DFS) in early-stage postmenopausal breast cancer patients. The goal was for women to achieve a 10% weight loss. The study had aimed to enroll 2,150 women, but due to a loss of funding, only 338 women were enrolled and the DFS endpoint could not be evaluated.
The researchers were able to evaluate the effect of the intervention on weight loss in the 171 women randomized to receive a telephone-based intervention compared with the 167 women who received mail-based weight loss guidance.
At 6 months, women who had the telephone-based weight loss intervention lost 5.3% of their body weight compared with 0.7% for women in the comparator arm, a statistically significant difference (4.3 kg vs 0.6 kg; P < .001). At 24 months, the intervention led to a 3.6% mean weight loss compared with 0.4% for the comparator arm. Women with both a high and low body mass index (BMI) experienced weight loss, but those who had a higher level of moderate-intensity activity prior to the start of the trial had the greatest weight loss.
All of the women in the study had a BMI of at least 24 at enrollment and received adjuvant letrozole therapy.
The mail-based intervention provided information on healthy living obtained from public sources delivered at the start of the study and at 1 year. Those in the telephone-based intervention group received telephone guidance from trained lifestyle coaches who helped to decrease caloric intake and increase physical activity to 150–200 minutes per week. Modeled on the Diabetes Prevention Program (DPP), the interventional phone calls were weekly for the first month, and then were scaled back to every 2 weeks for 2 months, once a month for 2 more months, followed by every 2 months until the 12-month time point, and then every 3 months for 2 years.
Seventy-five percent of those in the telephone-based intervention group completed the entire 2-year intervention program; 13 patients stopped early due to recurrence or death and 30 dropped out of the study.
The DPP-based telephone intervention program can lead to weight loss similar to that seen with face-to-face intervention, according to the authors. “Our results, combined with the recognition that obesity is associated with poor breast cancer outcomes, provide support for the conduct of a randomized trial using a telephone-based weight loss intervention that is adequately powered to detect clinically important effects on breast cancer outcomes,” they further concluded.
In an accompanying editorial, Melinda L. Irwin, PhD, of the Yale School of Public Health in New Haven, Connecticut, stated that “LISA provides us with a framework of how to deliver cost-effective weight loss interventions. Now all that is needed is the funding to conduct such a trial.”
Irwin proposed that pharmaceutical companies should, perhaps, be required to include lifestyle interventions as active comparators in clinical trials, particularly when current treatment options result in minimal or modest benefit. In the meantime, “breast cancer survivors need to be informed about the numerous benefits of maintaining a healthy weight and being physically active,” Irwin concluded.