Exercise manages fatigue during breast cancer treatment: A randomized controlled trial

Abstract

Fatigue is the most prevalent and debilitating symptom experienced by breast cancer patients receiving adjuvant chemotherapy or radiation therapy and few evidence‐based treatments are available to manage this distressing side‐effect. The purpose of this multi‐institutional randomized controlled trial was to determine the effects of exercise on fatigue levels during treatment for breast cancer. Sedentary women (N=119) with Stage 0–III breast cancer receiving outpatient adjuvant chemotherapy or radiation therapy were randomized to a home‐based moderate‐intensity walking exercise program or to usual care for the duration of their cancer treatment. Of participants randomized to exercise, 72% adhered to the exercise prescription; 61% of the usual care group adhered. The intention‐to‐treat analysis revealed no group differences in part because of a dilution of treatment effect as 39% of the usual care group exercised and 28% of the exercise group did not. When exercise participation was considered using the data analysis method of instrumental variables with principal stratification, a clinically important and statistically significant (p=0.03) effect of exercise on pretest‐to‐posttest change in fatigue levels was demonstrated. Adherence to a home‐based moderate‐intensity walking exercise program may effectively mitigate the high levels of fatigue prevalent during cancer treatment. Copyright © 2004 John Wiley & Sons, Ltd.