title: Fracture history and risk of breast and endometrial cancer.
abstract: Fractures in postmenopausal women may serve as a surrogate measure of bone density, reflecting long-term lower estrogen levels, and lower estrogen levels appear to be inversely associated with breast and endometrial cancer. Breast cancer cases aged 50-79 years (n = 5,559) and endometrial cancer cases aged 40-79 years (n = 739) were enrolled in a US case-control study in 1992-1994 to evaluate the relation between fractures and risk of breast and endometrial cancer. Controls for the breast cancer analysis (n = 5,829) and the endometrial cancer analysis (n = 2,334) were randomly selected from population lists (driver's license and Medicare files). Information on fracture history and other risk factors was obtained by telephone interview. Compared with women without a fracture in the past 5 years, the odds ratios for women with a history of fracture were 0.80 (95% confidence interval (CI): 0.68, 0.94) for breast cancer and 0.59 (95% CI: 0.40, 0.89) for endometrial cancer. Height loss (> or =2.5 cm) and recent fracture history were associated with the lowest risk of breast cancer (odds ratio = 0.62, 95% CI: 0.46, 0.83) and endometrial cancer (odds ratio = 0.15, 95% CI: 0.05, 0.43). These data suggest that the endogenous hormonal factors associated with increased fracture risk are also related to decreased breast cancer risk and, more strongly, to endometrial cancer risk.
authors.affiliation: University of Wisconsin Comprehensive Cancer Center, Madison, WI 53706, USA. pnewcomb@fhcrc.org
authors.forename: P A
authors.initials: PA
authors.lastname: Newcomb
authors.forename: A
authors.initials: A
authors.lastname: Trentham-Dietz
authors.forename: K M
authors.initials: KM
authors.lastname: Egan
authors.forename: L
authors.initials: L
authors.lastname: Titus-Ernstoff
authors.forename: J A
authors.initials: JA
authors.lastname: Baron
authors.forename: B E
authors.initials: BE
authors.lastname: Storer
authors.forename: W C
authors.initials: WC
authors.lastname: Willett
authors.forename: M J
authors.initials: MJ
authors.lastname: Stampfer
mesh_terms: D000328:Adult; D000368:Aged; D015992:Body Mass Index; D015519:Bone Density; D001943:Breast Neoplasms / Q000150:complications* / Q000453:epidemiology; D016022:Case-Control Studies; D016889:Endometrial Neoplasms / Q000150:complications* / Q000453:epidemiology; D015914:Estrogen Replacement Therapy; D005260:Female; D050723:Fractures, Bone / Q000150:complications*; D006801:Humans; D008875:Middle Aged; D017698:Postmenopause; D015203:Reproducibility of Results; D012307:Risk Factors; D014481:United States / Q000453:epidemiology