Factors Associated with Longitudinal Changes in Mammographic Density in a Multiethnic Breast Screening Cohort of Postmenopausal Women.

Background: Breast density is an important risk factor for breast cancer and is known to be associated with characteristics such as age, race, and hormone levels; however, it is unclear what factors contribute to changes in breast density in postmenopausal women over time. Understanding factors associated with density changes may enable a better understanding of breast cancer risk and facilitate potential strategies for prevention. Methods: This study investigated potential associations between personal factors and changes in mammographic density in a cohort of 3,392 postmenopausal women with no personal history of breast cancer between 2011 and 2017. Self-reported information on demographics, breast and reproductive history, and lifestyle factors, including body mass index (BMI), alcohol intake, smoking, and physical activity, was collected by an electronic intake form, and breast imaging reporting and database system (BI-RADS) mammographic density scores were obtained from electronic medical records. Factors associated with a longitudinal increase or decrease in mammographic density were identified using Fisher's exact test and multivariate conditional logistic regression. Results: 7.9% of women exhibited a longitudinal decrease in mammographic density, 6.7% exhibited an increase, and 85.4% exhibited no change. Longitudinal changes in mammographic density were correlated with age, race/ethnicity, and age at menopause in the univariate analysis. In the multivariate analysis, Asian women were more likely to exhibit a longitudinal increase in mammographic density and less likely to exhibit a decrease compared to White women. On the other hand, obese women were less likely to exhibit an increase and more likely to exhibit a decrease compared to normal weight women. Women who underwent menopause at age 55 years or older were less likely to exhibit a decrease in mammographic density compared to women who underwent menopause at a younger age. Besides obesity, lifestyle factors (alcohol intake, smoking, and physical activity) were not associated with longitudinal changes in mammographic density. Conclusions: The associations we observed between Asian race/obesity and longitudinal changes in BI-RADS density in postmenopausal women are paradoxical in that breast cancer risk is lower in Asian women and higher in obese women. However, the association between later age at menopause and a decreased likelihood of decreasing in BI-RADS density over time is consistent with later age at menopause being a risk factor for breast cancer and suggests a potential relationship between greater cumulative lifetime estrogen exposure and relative stability in breast density after menopause. Our findings support the complexity of the relationships between breast density, BMI, hormone exposure, and breast cancer risk.

Factors Associated with Women's Unwillingness to Decrease Alcohol Intake to Decrease Breast Cancer Risk.

OBJECTIVE: Alcohol intake is a known risk factor for breast cancer. National organizations recommend that women consume no more than one serving of alcohol per day, if at all; however, many women exceed this recommendation, and some are unwilling to decrease consumption. Our study sought to identify factors associated with women's unwillingness to decrease their alcohol intake to decrease their breast cancer risk. METHODS: 942 women in a screening mammography cohort were asked questions about their demographics, personal and family health history, lifestyle factors, and willingness/unwillingness to decrease alcohol intake to decrease their breast cancer risk. Univariate and multivariate analyzes of their responses were performed. RESULTS: 13.2% of women in our cohort indicated they were unwilling to decrease their alcohol intake to reduce their breast cancer risk. After adjusting for potential confounders, women who were 60 years and older were more than twice as unwilling to decrease their alcohol intake compared to their younger counterparts (P = .0002). Women who had an annual household income of more than $200,000 were 1.75 times more unwilling to decrease their alcohol intake compared to their less affluent counterparts (P = .033). Unwillingness was not significantly associated with race/ethnicity, education, having a first-degree family member with cancer, health perception, breast cancer risk perception, or BMI. CONCLUSIONS: Levels of unwillingness to decrease alcohol intake differed by age and household income. An opportunity is present to potentially decrease breast cancer risk in the community by educating women, especially older and more affluent women, about alcohol as a risk factor for breast cancer and the importance of limiting one's alcohol intake.

Rationale, Study Design, and Cohort Characteristics for the Markers for Environmental Exposures (MEE) Study.

Environmental factors have been linked to many diseases and health conditions, but reliable assessment of environmental exposures is challenging. Developing biomarkers of environmental exposures, rather than relying on self-report, will improve our ability to assess the association of such exposures with disease. Epigenetic markers, most notably DNA methylation, have been identified for some environmental exposures, but identification of markers for additional exposures is still needed. The rationale behind the Markers for Environmental Exposures (MEE) Study was to (1) identify biomarkers, especially epigenetic markers, of environmental exposures, such as pesticides, air/food/water contaminants, and industrial chemicals that are commonly encountered in the general population; and (2) support the study of potential relationships between environmental exposures and health and health-related factors. The MEE Study is a cross-sectional study with potential for record linkage and follow-up. The well-characterized cohort of 400 postmenopausal women has generated a repository of biospecimens, including blood, urine, and saliva samples. Paired data include an environmental exposures questionnaire, a breast health questionnaire, dietary recalls, and a food frequency questionnaire. This work describes the rationale, study design, and cohort characteristics of the MEE Study. In addition to our primary research goals, we hope that the data and biorepository generated by this study will serve as a resource for future studies and collaboration.