Background: Although it may improve life expectancy, treatment for breast cancer can significantly reduce quality of life. Many patients experience fatigue, weight gain, and reduced functional capacity during therapy, and most have significantly reduced levels of physical activity that persist even after completion of treatment. Individual reports and a systematic review suggest that exercise can address many of these problems.
The Study: Mutrie and colleagues conducted a randomized controlled trial of a 12-week, supervised exercise program for women having treatment for early breast cancer. Patients attending three Scottish outpatient oncology centers to receive chemotherapy or radiotherapy for breast cancer at stages 0 to III were recruited for the study. Women with cognitive dysfunction or unstable cardiac, hypertensive, or respiratory conditions were excluded from the study. Women who reported regular exercise were also excluded.
Participants were randomly allocated to an exercise intervention or usual treatment (control). In addition to receiving usual care, women in the intervention group participated in a program of twice-weekly exercise sessions and were encouraged to exercise at home. At the end of the 12 weeks, women in the intervention group were assisted in constructing an individualized ongoing exercise program.
The principal outcome measure was quality of life as evaluated by the standardized functional assessment of cancer therapy—general (FACT-G) questionnaire. Additional outcomes assessed included subscales for breast cancer, fatigue, and endocrine symptoms; the Beck depression inventory and measures of emotional health; recall of levels of physical activity and performance on a 12-minute walk; and shoulder mobility testing. Patients were assessed at baseline, 12 weeks, and six months.
Results: On average, the 203 participants were 50 years of age and entered the study six months after diagnosis. The intervention and control groups were comparable in all important variables.
After adjustment for age, baseline factors, treatment strategy, and center, the calculated intervention effect was significant at 12 weeks for distance walked in 12 minutes (effect estimate = 129 meters), minutes of moderate exercise reported per week (effect estimate = 182), shoulder mobility (effect estimate = 2.6), positive mood scores (effect estimate = 4.0), and the breast cancer–specific quality of life subscale (effect estimate = 2.5). Although scores on the principal outcome (FACT-G quality-of-life scale) improved more in the intervention group than in the control group, the difference was not statistically significant (P = .60). Other measures showed nonsignificant trends toward improved outcomes in the intervention group.
At six months, the difference in reported moderate exercise was still present but was no longer statistically significant. The other significant effects persisted for six months, and a positive effect on breast cancer–specific quality of life emerged. Women in the intervention group spent fewer nights in the hospital and made fewer primary care physician visits than controls during the six-month follow-up.
Conclusion: A 12-week exercise program was associated with several significant positive physical and psychological outcomes in women during treatment for early breast cancer. Most effects were sustained for six months, and an overall effect on quality of life emerged at the six-month follow-up.