title: Reproductive and menstrual factors and mammographic density in African American, Caribbean, and white women.
abstract: OBJECTIVE
  We investigated the associations between reproductive and menstrual risk factors for breast cancer and mammographic density, a strong risk factor for breast cancer, in a predominantly ethnic minority and immigrant sample.
  
  
  METHODS
  We interviewed women (42% African American, 22% African Caribbean, 22% White, 9% Hispanic Caribbean, 5% other) without a history of breast cancer during their mammography appointment (n = 191, mean age = 50). We used a computer-assisted method to measure the area and percentage of dense breast tissue from cranio-caudal mammograms. We used multivariable linear regression analyses to estimate the associations between reproductive and menstrual risk factors and mammographic density.
  
  
  RESULTS
  Age was inversely associated with percent density and dense area, and body mass index (BMI) was inversely associated with percent density. Adjusting for age, BMI, ethnicity and menopausal status, later age at menarche (e.g., β = -7.37, 95% CI: -12.29, -2.46 for age ≥ 13 years vs. ≤ 11 years), and any use of hormonal birth control (HBC) methods (β = -5.10, 95% CI: -9.37, -0.84) were associated with reduced dense area. Ethnicity and nativity (foreign- vs. US-born) were not directly associated with density despite variations in the distribution of several risk factors across ethnic and nativity groups.
  
  
  CONCLUSIONS
  The mean level of mammographic density did not differ across ethnic and nativity groups, but several risk factors for breast cancer were associated with density in ethnic minority and immigrant women.
authors.affiliation: Department of Epidemiology, Columbia University Mailman School of Public Health, 722 West 168th Street, New York, NY 10032, USA. pt140@columbia.edu
authors.forename: Parisa
authors.initials: P
authors.lastname: Tehranifar
authors.forename: Diane
authors.initials: D
authors.lastname: Reynolds
authors.forename: Julie
authors.initials: J
authors.lastname: Flom
authors.forename: Loralee
authors.initials: L
authors.lastname: Fulton
authors.forename: Yuyan
authors.initials: Y
authors.lastname: Liao
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Kudadjie-Gyamfi
authors.forename: Mary Beth
authors.initials: MB
authors.lastname: Terry
mesh_terms: D000328:Adult; D001741:Black or African American / Q000706:statistics & numerical data; D001940:Breast / Q000166:cytology*; D001943:Breast Neoplasms / Q000000981:diagnostic imaging / Q000453:epidemiology / Q000208:ethnology / Q000209:etiology*; D002277:Carcinoma / Q000000981:diagnostic imaging / Q000453:epidemiology / Q000208:ethnology / Q000209:etiology*; D017691:Caribbean Region / Q000208:ethnology; D002452:Cell Count; D005006:Ethnicity / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D008327:Mammography; D008598:Menstruation / Q000502:physiology*; D008875:Middle Aged; D017584:Reproductive History; D012307:Risk Factors; D044465:White People / Q000706:statistics & numerical data