Researchers found that breast cancer survivors who were prescribed adjuvant endocrine therapy and regularly performed moderate physical activity reported better health-related quality-of-life.
A study published in Cancer found that among women taking adjuvant endocrine therapy, moderate levels of physical activity may be correlated with fewer medication-related symptoms and better overall reports of health-related quality-of-life (QOL).
However, low levels of physical activity were observed in the overall study population and particularly among black women, suggesting a need to identify successful strategies for promoting physical activity.
“Because most [hormone receptor (HR)-positive breast cancer] survivors will be prescribed to take [adjuvant endocrine therapy] for at least 5 years, identifying targets to enhance QOL is a priority,” the authors wrote. “There have been limited empirical data about [adjuvant endocrine therapy]-related symptoms and [physical activity] in diverse [breast cancer] survivors, so this study begins to fill gaps in this area.”
Researchers had participants from the Women’s Hormonal Initiation and Persistence (WHIP) study who had HR-positive breast cancer and were taking adjuvant endocrine therapy complete standardized surveys about their health-related QOL, adjuvant endocrine therapy-related symptoms, and levels of physical activity using validated measures. Overall, a total of 485 survivors made up the final analysis, including 349 non-Hispanic white breast cancer survivors and 136 non-Hispanic black breast cancer survivors.
In a bivariate analysis, black race, a high body mass index (BMI), and being on aromatase inhibitors (rather than tamoxifen) were associated with lower physical activity. Comparably, in multivariate analysis, lower self-reported physical activity was associated with a high BMI (P = .02) and chemotherapy uptake (P = .006).
“Similarly to other reports, black survivors reported lower levels of [physical activity] across all categories in comparison with white survivors. Reasons for lower [physical activity] are not well elucidated in this population but may include negative attitudes about exercise, a lack of access to facilities, and a lack of time,” the authors explained. “Future studies that examine the level and type of [physical activity] in black women are needed to inform interventions.”
Ultimately, better health-related QOL (P = .01), less severe overall adjuvant endocrine therapy-related symptoms (P = .02), and less severe gynecological symptoms (P = .03) were associated with increasing levels of moderate physical activity.
Notably, the researchers suggested that though both moderate aerobic exercise and vigorous aerobic exercise, or a combination of the 2, are recommended for cancer survivors, moderate-intensity activity may be more feasible to achieve for survivors not currently meeting their physical activity recommendations. This is partially due to the fact that most survivors report low levels of physical activity at diagnosis, fail to meet their recommended physical activity levels after treatment, and may endure physical limitations to vigorous physical activity. Additionally, walking, which accounts for the majority of self-reported moderate-intensity activity, can be more precisely reported than vigorous-intensity activities.
The authors also indicated that “residual confounding by diet and other ‘healthy lifestyle’ factors that are associated with [physical activity] intensity cannot be ruled out as an explanation.”
“Achieving moderate levels of [physical activity] may be an attainable goal for many women taking [adjuvant endocrine therapy],” the authors wrote. “A moderate level of [physical activity] also appears to be practical because it includes a range of activities as part of daily living (e.g., heavy cleaning, mowing the lawn, and walking).”
Importantly, the investigators recommended that future studies examine how physical activity affects symptoms for this patient population over time, as well as other factors such as treatment adherence.
Sheppard VB, Dash C, Nomura S, et al. Physical Activity, Health-Related Quality of Life, and Adjuvant Endocrine Therapy-Related Symptoms in Women With Hormone Receptor-Positive Breast Cancer. Cancer. doi: 10.1002/cncr.33054.