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.

WCRF/AICR recommendation adherence and breast cancer incidence among postmenopausal women with and without non‐modifiable risk factors

“…Previous research indicates that women at high risk for breast cancer, due to a family history of breast cancer, are no more likely to adhere to cancer prevention recommendations . Consistent with prior studies, when individual non‐modifiable risk factors were evaluated, such as family history, benefits of adherence did not appear to differ by the presence/absence of a non‐modifiable risk factor . However, among women with multiple non‐modifiable risk factors, higher adherence to cancer prevention recommendations was not associated with breast cancer risk.…”

“…8,9 Consistent with prior studies, when individual non-modifiable risk factors were evaluated, such as family history, benefits of adherence did not appear to differ by the presence/absence of a non-modifiable risk factor. [36][37][38] However, among women with multiple nonmodifiable risk factors, higher adherence to cancer prevention recommendations was not associated with breast cancer risk. One possible explanation for the somewhat weaker association among women with multiple non-modifiable risk factors may be that the effects of the non-modifiable risk factor moderate the benefits of adherence.…”

Family-based Breast Cancer Prevention Efforts in Adolescence

“…When we examined whether adherence to these ACS guidelines was also relevant to high risk women in a familybased cohort, we observed that adherence to ACS guidelines was associated with a 40% lower mortality rate. 4 Even in the absence of stronger effects from modifiable factors in individuals at higher risk, similar relative risks means that those at higher absolute risk will have a greater absolute effect from successful cancer prevention efforts. Thus, reducing risk by 30% to 50%, the range of many of the behavioral risk factors and breast cancer, translates into a much larger absolute risk reduction in individuals with a family history.…”

Breast Cancer and BRCA1 and BRCA2 Pathogenic Variants

“…Amongst BRCA carriers, smoking, increased weight and reduced physical activity further increases the risk of breast cancer. These lifestyle measures need to commence in adolescence and adherence to this (150 min weekly activity, BMI < 25, <1 alcoholic drink daily) has been shown to reduce mortality in BRCA carriers by almost 60% [54].…”