The impact of cancer prevention guideline adherence on overall mortality in a high-risk cohort of women from the New York site of the Breast Cancer Family Registry.

Abstract

The American Cancer Society (ACS) recommends at least 150 min of moderate intensity physical activity per week, alcohol intake of ≤1 drink per day, and maintaining a body mass index (BMI) of <25 kg/m2 for breast cancer prevention. Adherence to these guidelines has been linked to lower overall mortality in average-risk populations, it is not known if mortality reduction extends to women at higher risk given their family history of breast cancer. We followed 2,905 women from a high-risk Breast Cancer Family Registry in New York, of which 77 % were white non-Hispanic and 23 % were Hispanic. We collected information on BMI, physical activity, and alcohol intake at baseline and prospectively followed our cohort for outcomes based on questionnaires and National Death Index linkage. We used Cox regression to examine the relation between adherence to ACS guidelines and overall mortality and examined effect modification by race, age, and BRCA status. There were 312 deaths after an average of 9.2 ± 4.1 years of follow-up. Adherence to all three ACS recommendations was associated with 44–53 % lower mortality in women unaffected with breast cancer at baseline [Hazard Ratio (HR) 0.56, 95 % CI (0.33–0.93)] and in women affected with breast cancer at baseline [HR 0.47, 95 % CI (0.30–0.74)]. These associations remained after stratification by age, race, and BRCA status {e.g., BRCA1 and/or BRCA2 carriers [HR 0.39, 95 % CI (0.16–0.97)]}. These results support that women at high risk, similar to women at average risk, may also have substantial benefits from maintaining the ACS guidelines.