title: Recent use of hormone replacement therapy and the prevalence of colorectal adenomas.
abstract: The etiological role of hormone replacement therapy (HRT) (including estrogen only, combined estrogen-progesterone, and progesterone only) in colorectal neoplasia remains unclear. Several large studies have reported a reduced risk of colorectal cancer among HRT users; however, other studies have given inconsistent results. We examined the association between HRT and colorectal adenomatous polyps, precursors of colorectal cancer, among female participants in a case-control study. Subjects were members of a prepaid health plan in Los Angeles who underwent sigmoidoscopy in 1991-1993. Participants received an in-person interview and completed a food frequency questionnaire. A total of 187 histologically confirmed cases and 188 controls, ages 50-75 years, were included in the analysis. Compared with women who did not use HRT during the year before sigmoidoscopy, recent users had an adjusted odds ratio of 0.57 (95% confidence interval, 0.35-0.94). Duration of use was inversely related to the prevalence of colorectal adenomas, with a multivariate-adjusted odds ratio of 0.49 (95% confidence interval, 0.25-0.97) for use of 5 years or more. These results support a protective effect of HRT on colorectal adenomatous polyps.
authors.affiliation: Department of Epidemiology, UCLA School of Public Health, Los Angeles, California 90095, USA.
authors.forename: M J
authors.initials: MJ
authors.lastname: Chen
authors.forename: M P
authors.initials: MP
authors.lastname: Longnecker
authors.forename: H
authors.initials: H
authors.lastname: Morgenstern
authors.forename: E R
authors.initials: ER
authors.lastname: Lee
authors.forename: H D
authors.initials: HD
authors.lastname: Frankl
authors.forename: R W
authors.initials: RW
authors.lastname: Haile
mesh_terms: D018256:Adenomatous Polyps / Q000453:epidemiology / Q000209:etiology / Q000517:prevention & control*; D000368:Aged; D002140:California / Q000453:epidemiology; D015179:Colorectal Neoplasms / Q000453:epidemiology / Q000209:etiology / Q000517:prevention & control*; D003430:Cross-Sectional Studies; D015914:Estrogen Replacement Therapy; D005260:Female; D006801:Humans; D015994:Incidence; D008875:Middle Aged; D012306:Risk