Cancer
Adherence to a healthy lifestyle and physical health decline after chemotherapy or endocrine therapy in breast cancer survivors Cassandra York* Cassandra York York York York York Department of Population Science, American Cancer Society, Atlanta, GA
Background. Women with a history of breast cancer (BC) experience greater physical health decline compared to age-matched cancer-free women. We investigated whether adherence to a healthy lifestyle could mitigate this decline.
Methods. This analysis included 1,862 women with BC (diagnosed 2015-2020) and 18,610 cancer-free women matched on age and date of returned survey from the Cancer Prevention Study 3. All were non-current smokers. Adherence to a healthy lifestyle was assessed using the American Cancer Society guideline for cancer survivors score, which includes body mass index (BMI), physical activity, and diet from the 2015 survey. The score (range: 0-8) was categorized as low (0-4) or high (5-8) adherence to a healthy lifestyle. Physical health was assessed using the Patient-Reported Outcomes Measurement Information System (PROMIS) Global Health Scale at three time points: before diagnosis, and <4 and ≥4 years post-diagnosis. We used multivariable linear regression adjusted for matching variables to estimate the association between a combined treatment-lifestyle variable and PROMIS score.
Results. Median age at diagnosis was 60 years (interquartile range [IQR]: 52-65). The median lifestyle score was 5 (IQR: 4-7) for BC survivors and 6 (IQR: 4-7) for cancer-free women. Patients who received chemotherapy and had a high lifestyle adherence score had better physical health after diagnosis compared to cancer-free women with a low adherence score (<4 years: β=0.83, 95% CI: 0.10, 1.56; ≥4 years: β=1.71, CI: 0.42, 3.01). In contrast, patients who received chemotherapy but had a low adherence score had significantly lower physical health than cancer-free women with a low adherence score (<4 years: β=-2.84, 95% CI: -3.86, -1.82; ≥4 years: β=-2.16, 95% CI: -3.90, -0.42).
Conclusion. High pre-diagnosis adherence to a healthy lifestyle was associated with greater physical health in BC survivors, including those who received chemotherapy.