TOPLINE

Higher adherence to the American Cancer Society (ACS) lifestyle guidelines was linked to better physical health among survivors of breast cancer, including those treated with chemotherapy. Chemotherapy-treated survivors with high alignment had better physical health than age-matched women without cancer who had low alignment, and their predicted physical health was comparable to that of the average US population.

METHODOLOGY

• Survivors of breast cancer, especially those treated with chemotherapy, commonly report long-term declines in physical health relative to age-matched women who have never had cancer. A previous analysis found declines only in chemotherapy-treated survivors, though it did not evaluate lifestyle behaviors. It remains unclear whether adhering to the ACS lifestyle guidelines is linked to better physical health in survivors.
• To find out, researchers conducted a prospective cohort study that analyzed data from the ACS CPS-3 study, including 1610 breast cancer survivors (median age at diagnosis, 59.7 years) and 16,100 age-matched women without cancer. At the 2015 survey, none of the participants had a cancer diagnosis or were current smokers. Survivors had a first breast cancer diagnosis through January 2022 and returned a survey at least 90 days after diagnosis.
• Guideline alignment was scored from 0 to 8 based on survey responses on BMI, physical activity, diet, and alcohol consumption; it was categorized as low (0-4) or high (5-8).
• Physical health was measured using the Patient-Reported Outcomes Measurement Information System Global Health Scale before breast cancer diagnosis, less than 3 years after diagnosis, and 3 or more years after diagnosis, with T-scores standardized to the US general population (mean, 50).  
• Survivors were grouped by treatment (no chemotherapy or endocrine therapy, endocrine therapy without chemotherapy, and chemotherapy with or without endocrine therapy) and by low or high lifestyle alignment; each group was compared with women without cancer who had low lifestyle alignment, adjusting for age and time since diagnosis.

TAKEAWAY

• Higher alignment with ACS guidelines was associated with better physical health during all three assessment periods, irrespective of treatment status.
• Chemotherapy-treated survivors with low guideline alignment had significantly worse physical health than women without cancer who had low alignment, both within 3 years of diagnosis (regression coefficient [beta], -2.67; 95% CI, -3.77 to -1.58) and 3 or more years after diagnosis (beta, -2.10; 95% CI, -3.70 to -0.51).
• Chemotherapy-treated survivors with high guideline alignment had better physical health than women without cancer who had low alignment, at less than 3 years after diagnosis (beta, 1.09; 95% CI, 0.30-1.89).
• Within 3 years of diagnosis, predicted physical health among women without cancer differed by about 9 points across the full range of ACS guideline scores, a larger difference than the roughly 3-point deficit linked to chemotherapy. Chemotherapy-treated survivors were predicted to reach physical health comparable to that of the average US population (T-score, 50) at scores of about 5-6, compared with a score of about 3 in women without cancer.

IN PRACTICE

"These findings support a potential role for healthy lifestyle behaviors in maintaining physical health among BC [breast cancer] survivors, including those treated with chemotherapy," the authors of the study wrote.

SOURCE

The study, led by Clara Bodelon, PhD, MS, American Cancer Society, Atlanta, was published online in the Journal of the National Cancer Institute.

LIMITATIONS

Treatment data covered only first-course therapy and lacked details about duration, timing, specific chemotherapy regimens, or HER2-targeted therapies. Information on cancer recurrence was not available, and follow-up was too short to assess outcomes in longer-term survivors. Physical health was self-reported and may have differed from objective measures of function. Reverse causation may have occurred, as women with better physical health may have been more likely to maintain behaviors aligned with ACS guidelines.

DISCLOSURES

The American Cancer Society funded the creation, maintenance, and updating of the CPS-3 cohort. The authors reported no relevant conflicts of interest.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.