Physical activity may provide some level of protection against the development of breast cancer; however, the impact of physical activity following a breast cancer diagnosis remains unknown. Previous studies suggest that both strenuous and moderate exercise have comparable benefits on the incidence of breast cancer; however, there is limited data on survival outcomes.
A recent letter published in the journal JAMA Network Open discusses the association of physical activity beyond essential everyday functions with the mortality risk among breast cancer survivors.
Study: Association of Physical Activity With Risk of Mortality Among Breast Cancer Survivors. Image Credit: TORWAISTUDIO / Shutterstock.com
About the study
The current study included post-menopausal breast cancer survivors who had received their initial diagnosis at least two years prior to the start of the study. More specifically, the study participants' early-stage breast cancer diagnosis was provided between 1996 and 2012.
Baseline interviews were conducted between August 1, 2013, and March 31, 2015. After that, the participants were followed up with until their death or when the study ended on April 30, 2022.
The Fatigue Severity Inventory and the Godin-Shephard Leisure-Time Physical Activity Questionnaire (GSLTPAQ) was used to assess physical activity and leisure. Exercise patterns were categorized as insufficiently active, moderately active, and active at baseline based on exercise habits during a seven-day period.
Physical activity reduces risk of death due to breast cancer
A total of 315 participants were included in the study, all women. The mean age at the interview was 71 years.
A total of 217 participants were non-Hispanic White, 28 were Pacific or Asian Islander, 66 were African American or Black, and four were Hispanic. Unfortunately, five participants died within the follow-up period due to breast cancer.
Mortality rates were 12.9 per 1,000 person-years (PY) for active participants, 32.9/1000 PY for insufficiently active participants, and 13.4/1000 PY for moderately active participants. Taken together, moderately active or active participants were associated with a 60% reduced risk of death compared to insufficiently active participants.
Taken together, these findings indicate that both active and moderately active women diagnosed with breast cancer were less likely to die from breast cancer as compared to entirely inactive participants. Thus, the care management plans for women diagnosed with breast cancer should incorporate physical activity to increase the likelihood of survival and improve their overall quality of life.
A key limitation of the current study includes the lack of information on the participants' daily diet habits. Furthermore, physical activity was self-reported by the participants and is subject to bias; therefore, future studies incorporating technological devices such as pedometers and heart rate monitors may be beneficial.
- Chen, L. H., Irwin, M. R., Olmstead, R., et al. (2022). Association of Physical Activity With Risk of Mortality Among Breast Cancer Survivors. JAMA Network Open. doi:10.1001/jamanetworkopen.2022.42660.