Adherence to lifestyle-related cancer prevention guidelines and breast cancer incidence and mortality

Menée à partir de données portant sur 106 126 femmes (durée moyenne de suivi : 12,5 ans), cette étude évalue l'association entre l'adhésion aux recommandations de "l'American Cancer Society" en matière de comportements de santé (alimentation, activité physique, ...) et le risque de cancer du sein (7 088 cas), la mortalité globale (1 162 décès) ou la mortalité spécifique (462 décès)

Résumé en anglais

Background : Breast cancer is the most common cancer in women. Many lifestyle factors have been associated with an increased risk of breast cancer incidence and mortality. An index-based approach to analyzing adherence to American Cancer Society (ACS) guidelines as a whole may better explain associations between lifestyle variables and breast cancer incidence and mortality.

Methods : We created an index based on ACS-specific guidelines, including body mass index (BMI), physical activity, alcohol intake, tobacco use, daily time spent watching television, and certain dietary habits. Cox proportional hazards regression was used to model the association between the lifestyle index and primary breast cancer and breast cancer specific mortality in the NIH-AARP cohort.

Results : We identified 7,088 women with incident breast cancer, 1,162 deaths overall, and 462 deaths due to breast cancer. Compared with the lowest quintile of lifestyle index score (meeting fewest guidelines), women in the highest quintile had a 24% lower risk of breast cancer (HR=0.76, 95% CI: 0.70, 0.82) and 37% lower risk of all-cause mortality (HR=0.63, 95% CI: 0.53, 0.76), while the association with breast cancer-specific mortality was non-significant.

Conclusions : Healthier pre-diagnosis lifestyle is associated with a decreased risk of breast cancer and all-cause mortality in the NIH-AARP cohort.