A slowly progressive weight lifting program for breast cancer survivors did not increase their risk of lymphedema (arm swelling and discomfort), according to a study that will appear in the December 22/29 issue of JAMA. The study is being released early online to coincide with its presentation at the San Antonio Breast Cancer Symposium.
Lymphedema is a frequent complication among breast cancer survivors and ranks high among their concerns, as it may impair arm function and quality of life. "Breast cancer survivors at risk for lymphedema alter activity, limit, activity, or both from fear and uncertainty about their personal risk level, and upon guidance advising them to avoid lifting children, heavy bags, or other objects with the at-risk arm. Such guidance is often interpreted in a manner that deconditions the arm, increasing the potential for injury, overuse, and, ironically, lymphedema onset," according to background information in the article. The authors add that adherence to these precautions may limit physical recovery after breast cancer. Lymphedema often occurs after lymph vessels or lymph nodes in the axilla (armpit) are removed by surgery or damaged by radiation, impairing the normal drainage of lymphatic fluid.
Kathryn H. Schmitz, Ph.D., M.P.H., of the University of Pennsylvania School of Medicine and Abramson Cancer Center, Philadelphia, and colleagues examined the incidence of lymphedema after a 1-year weight lifting intervention among survivors at risk for breast cancer-related lymphedema (BCRL). The randomized controlled trial included 154 female breast cancer survivors who had been diagnosed 1 to 5 years prior to entry in the study and had at least 2 lymph nodes removed and were without clinical signs of BCRL at study entry. Participants (ages 36 to 75 at the beginning of the study) were randomized to either the weight lifting intervention, which included a gym membership and 13 weeks of supervised instruction, with the remaining 9 months unsupervised, or to no exercise (control group). Data collection ended in August 2008. A total of 134 participants completed follow-up measures at 1 year.
The researchers found that the proportion of women who experienced new BCRL onset was 11 percent (8 of 72) in the weight lifting intervention group and 17 percent (13 of 75) in the control group. "Among women with 5 or more lymph nodes removed, the proportion who experienced incident BCRL onset was 7 percent (3 of 45) in the weight lifting intervention group and 22 percent (11 of 49) in the control group. Clinician-defined BCRL onset occurred in 1 woman in the weight lifting intervention group and 3 women in the control group (1.5 percent vs. 4.4 percent)."
"The majority of breast cancer survivors do not have lymphedema; however, they alter the use of their arms and upper body activities out of fear of developing lymphedema. The findings from our trial should help clarify clinical advice to patients who have completed breast cancer treatment regarding the safety of resuming or beginning a weight lifting program," the authors write.
The researchers note that the primary goal of this study was to test safety of weight lifting, not superiority, and that additional research is needed before concluding that weight lifting prevents lymphedema. "However, even with the finding of no harm, our results combined with previously published results for women with breast cancer-related lymphedema suggest that the many health benefits of weight lifting should now become available to all breast cancer survivors."