Life Course Developmental and Reproductive Predictors of Increased Mammographic Breast Density in Black Women - PROJECT SUMMARY/ABSTRACT Despite improvements in breast cancer incidence and mortality rates in the general population, breast cancer incidence rates in Black women have continued to rise and they exhibit the highest breast cancer mortality rate out of any other racial population. Increased mammographic density has been well established as one of the strongest, independent breast cancer risk factors. However, to date, there have been very few studies that have included Black women in our understanding of mammographic breast density, which is a significant limitation given that Black women are more likely to have denser breasts. Breast cancer disparities are likely multifactorial and driven by related combinations of social determinants of health, the paucity of data in Black women has resulted in a limited understanding of the contribution of breast density to cancer disparities. While race, a social construct, is an unlikely direct predictor of mammographic density, it can serve as a marker of differential lived experiences due to various cultural practice, environmental exposures, and experiences of structural racism. Childhood, puberty, and pregnancy represent times of increased breast development and susceptibility to such exposures and host factors. In fact, Black women display differing anthropometric and reproductive patterns – which are known contributors to mammographic density in white women – across their life course. We hypothesize that unique distributions of body and sexual maturation characteristics during childhood and puberty, and varying reproductive outcomes during adulthood may, in part, explain the increased incidence of high mammographic density in Black women. Using the Black Women’s Health Study, the largest cohort of Black women in the United States (59,000 women), we have developed a large mammogram repository consisting of over 10,000 participants. Leveraging this analytic tool, in Aim 1, we will determine the associations of anthropometric, body habitus, and sexual development characteristics across the life course with percent and absolute mammographic density. Aim 2 will explore the association between specific pregnancy-related characteristics and percent and absolute mammographic density. This will be the first study to assess factors from birth to adulthood as predictors of mammographic density in Black women. Successful completion of these aims will offer insight into the etiology of increased mammographic density in Black women and contribute to a better understanding of breast cancer incidence and survival disparities in this vulnerable population. This proposal also integrates advanced epidemiologic techniques and fundamental biostatistical skills with clinical training to prepare the PI for a career as an independent physician scientist with expertise in cancer health disparities research.
