Alignment with lifestyle recommendations and physical health in breast cancer survivors and women without cancer

BACKGROUND: Breast cancer (BC) survivors, particularly those treated with chemotherapy, experience declines in physical health compared with age-matched women without cancer. We investigated whether alignment with healthy lifestyle behaviors, including body weight, physical activity, diet, and alcohol, was associated with better physical health among BC survivors. METHODS: This analysis included 1,610 BC survivors and 16,100 age- and survey date-matched women without cancer from the American Cancer Society (ACS) Cancer Prevention Study-3 prospective cohort. Lifestyle alignment was assessed using the ACS guideline score (0-8), categorized as low (0-4) or high (5-8). Physical health was measured using the Patient-Reported Outcomes Measurement Information System Global Health Scale. Associations between a combined treatment-lifestyle variable and physical health were estimated using linear regression adjusted for matching factors at pre-diagnosis, <3, and ≥3 years post-diagnosis. RESULTS: Higher guideline alignment was associated with better physical health (P < 0.001). Compared with women without cancer and low alignment, chemotherapy-treated BC survivors with low alignment had worse physical health (<3 years: β = -2.67, 95% CI = -3.77 to - 1.58; ≥3 years: β = -2.10, 95% CI = -3.70 to - 0.51). In contrast, chemotherapy-treated survivors with high alignment had better physical health (<3 years: β = 1.09, 95% CI = 0.30 to 1.89; ≥3 years: β = 2.56, 95% CI = 1.40 to 3.72). Survivors with higher alignment were predicted to have physical health comparable to the average U.S. population. CONCLUSION: Higher alignment with ACS lifestyle guidelines was associated with better physical health among BC survivors, including chemotherapy-treated survivors. These findings highlight the potential relevance of healthy lifestyle behaviors for supporting physical health among survivors.