Home-based exercise, weight loss interventions do not improve breast cancer-related lymphedema

In Clinical Trials by Barbara Jacoby

By: Schmitz KH, et al. JAMA Oncol.

From: healio.com

A home-based exercise and/or weight loss intervention failed to improve breast cancer-related lymphedema outcomes among breast cancer survivors with overweight, according to results from the WISER Survivor randomized trial published in JAMA Oncology.

“The present study sought to test the effects of exercise, weight loss and combined exercise and weight loss interventions on clinical lymphedema outcomes in comparison with a control group,” Kathryn H. Schmitz, PhD, MPH, professor in the department of public health sciences and in the department of physical medicine and rehabilitation at Penn State Cancer Institute, and colleagues wrote. “The study’s hypothesis was that the combined weight loss and exercise program would achieve the greatest reduction in arm swelling and that a lesser degree of arm-swelling reduction would be observed with the weight loss-only program.”

In the 12-month, 2 x 2 factorial, randomized clinical trial, Schmitz and colleagues evaluated 351 survivors of breast cancer (62.1% white, 34.8% black) with overweight and breast cancer-related lymphedema over a 4-year period from 2012 to 2016. The trial required that participants be 6 or more months posttreatment, have a BMI of 25 to 50 (overweight or obese), be able to walk unassisted for more than 6 minutes and have no exercise-limiting medical conditions.

Median time since diagnosis of breast cancer was 6 years (range, 1-29).

Researchers randomly assigned participants to a control group, in which they received facility-based lymphedema care without home-based exercise or weight loss interventions (n = 90; mean age, 59 years; mean BMI, 34), or one of three interventions:

  • a 52-week, home-based exercise program of strength/resistance training twice weekly and 180 minutes of walking weekly (n = 87; mean age, 59.1 years; mean BMI, 34);
  • a weight loss intervention consisting of 20 weeks of meal replacements and 52 weeks of counseling on lifestyle changes (n = 87; mean age, 59.4 years; mean BMI, 33.8); or
  • a combination of the home-based exercise and weight loss interventions (n = 87; mean age, 60 years; mean BMI, 34.2).

Researchers changed the study’s primary outcome from lymphedema clinical events — including incident flare-ups or cellulitis — to the percentage of interlimb volume change from baseline to 12 months, because a reduction in funding forced them to reduce the study’s sample. They used the Clinical Lymphedema Evaluation of the Upper Extremity (CLUE) tool, developed for the trial, to standardize clinical assessments of lymphedema, and assessed self-reported symptoms using the Norman Lymphedema Survey.