Mammographic Density in African American, Caribbean and Caucasian Women

Breast cancer risk and prevalence of many breast cancer risk factors vary by ethnicity and acculturation, but it is unclear whether similar variations exist for mammographic breast density, an intermediate marker of breast cancer. We examined ethnic variation in mammographic density in 168 women without a history of breast cancer, undergoing screening mammography (average age = 50.2). The sample consisted of 22% non-Hispanic Caucasian, 44% non-Hispanic African American, 23% Afro-Caribbean, and 10% Caribbean Hispanic. We used generational status as a proxy for acculturation as follows: U.S-born (U.S.-born participants with U.S.-born parents), 2nd generation (U.S.-born participants with foreign-born parents), 1st generation (foreign-born participants). We digitized mammograms and evaluated the proportion of dense area (in percentage) using a computer software. We used multivariable linear regression model to investigate the associations of percent density with race/ethnicity, generational status, current body mass index (BMI, kg/m2) and age. Age and BMI were significantly inversely associated with percent density (p< 0.001), with percent density being more than twice higher in normal weight (BMI<25) than in obese women (BMI≥30). As compared with African Americans, all other ethnic groups had lower percent density after adjusting for age and BMI, but these differences were not statistically significant. Generational status was not associated with density in the overall sample or among Caribbean women only. In conclusion, we did not observe significant influences on mammographic density by ethnicity and generational status in an urban multiethnic sample.