Few breast cancer survivors meet national exercise recommendations during the 10 years after being diagnosed, even though they are among the women who could most benefit from regular physical activity, according to a study by researchers at Fred Hutchinson Cancer Research Center. Prior studies and available evidence show a strong association between physical activity and reduced mortality, extended survival, and higher quality of life among breast cancer survivors.
The current study, published online ahead of print in the journal Cancer Epidemiology, Biomarkers and Prevention, followed an ethnically diverse group of 631 breast cancer survivors ages 18 to 64 from New Mexico, Los Angeles County, and western Washington for 10 years.1 Recreational aerobic activity was ascertained for each woman via interviews and questionnaires the year before diagnosis and again 2, 5, and 10 years after enrollment into the study.
U.S. physical activity guidelines call for at least 150 minutes per week of moderate exercise or at least 75 minutes per week of vigorous activity.
Prior to diagnosis, 34% of the women met U.S. physical activity guidelines. This percentage remained unchanged 2 years later. The percentage of women who complied with the activity guidelines increased to 39.5% at 5 years but then dropped to 21.4% at 10 years. Overall, researchers found that fewer than 8% of the survivors met U.S. physical activity guidelines at all of the study time points.
The predictors of physical activity in this population remain poorly understood, according to the authors. ■
Disclosure: Funding for the study was provided by grants from the National Institutes of Health. Coauthors included researchers from the National Cancer Institute, City of Hope National Medical Center, University of Louisville and the University of Washington.
1. Mason C, et al: Cancer Epidemiol Biomarkers Prev. April 10, 2013 (early release online).