Predictors of use of prevention strategies among women at high-risk for breast cancer.

Abstract

10554 Background: Uptake of chemoprevention and prophylactic surgery among women at high risk for breast cancer is low, despite proven efficacy. We evaluated breast cancer risk factors as predictors of uptake of prevention treatment (PT) to better understand potential associations with these decisions. Methods: An IRB approved registry established in 2003 at the University of Vermont of high-risk women was used to evaluate the association between both modifiable (obesity, sedentary lifestyle and alcohol use) and non-modifiable (age, history of benign breast disease [BDD], genetic predisposition) risk factors and uptake of PT. Women were eligible for inclusion in this analysis if they had one of the following risk factors (BDD, strong family history, > 20% lifetime modeled risk or genetic predisposition) and completed questionnaires regarding diet and physical activity. Alcohol use was assessed using a health questionnaire and physical activity was assessed using a 7-Day Physical Activity Recall questionnaire. We used logistic regression to estimate odds ratios (OR). Results: 504 women were included and had been followed for median of 13 years. Mean age was 44.5 years (range 19 – 75), 98% were Caucasian, and mean BMI was 26.9 (range 17-57). 78% had a family history of breast cancer, 60% had >20% lifetime modeled risk, 14% had a history of benign breast disease (BBD), and 9% of women had confirmed genetic risk in high or moderate risk genes. Women may have had more than one risk factor. 55% were physically active and 55%. 4.2% were sedentary and 12.3% consumed > 1 alcoholic beverage daily. 20.8% of the cohort participated in PT (8.1% took chemoprevention, 2.0% underwent prophylactic bilateral total mastectomy and 10.7% underwent risk reducing salpingo-oophorectomy). Among non-modifiable risk factors, age, genetic predisposition (ORadj 8.66, 95% CI 2.30–32.33, p < 0.0001), and history of benign breast disease (ORadj 4.09, 95% CI 1.89–8.86, p < 0.001) were associated with uptake of PT. Increasing age was associated with increasing uptake (ptrend was > 0.0001) and highest among women aged 60-69 years (ORadj8.19, 95% CI 2.87-23.37 relative to women aged < 40). Women with a strong family history were significantly less likely to take up PT (p = 0.04). BMI, physical activity status and alcohol use were not associated with uptake of PT. Conclusions: Like other studies, we found a low uptake of PT among women at high risk for developing breast cancer. We found that modifiable risk factors were not associated with uptake of PT, which might suggest that high-risk women with modifiable risk factors could be targeted for interventions designed to modify risk (i.e. chemoprevention, weight reduction, etc). Interestingly, women with a strong family history may be less likely to take up PT, and studies to further examine this relationship may identify opportunities for interventions to improve uptake.