Effect of estrogen-progestin and estrogen on mammographic density.
OBJECTIVE
To assess the different effects between non-treatment, estrogen and estrogen-progestin regimens on changes in mammographic density in postmenopausal women.


METHODS
A historical cohort of 105 postmenopausal women who attended the Menopause Clinic, Srinagarind Hospital, Khon Kaen, Thailand, and received 1 of 3 regimens: nontreatment, estrogen or estrogen-progestin (35 in each group). Mammographic examinations were done before and after a 12-24-month period of hormone therapy. Breast density (mammographic density, recorded in the medical records) between the 2 examinations in each group were compared.


RESULTS
An increase in mammographic density occurred among women receiving hormone therapy: 40% (14 of 35) in the estrogen-progestin group and 20% (7 of 35) in the estrogen-only group, but no variation in density was observed in the nontreatment group. The increase in mammographic density occurring in women on hormone therapy, as compared to the nontreatment group, was statistically significant (estrogen-progestin, 95% CI 20.91-59.09; estrogen, 95% CI 3.89-36.11). When the different treatment types were compared, the estrogen-progestin group tended to have a higher prevalence of mammographic density change than the estrogen-only group, but the difference was not statistically significant (95% CI -3.81-43.81).


CONCLUSIONS
Hormone therapy was associated with increased mammographic density. Apparently the estrogen-progestin regimen affects breast density more than estrogen-only does.
Kaewrudee
Srinaree
S
Department of Obstetrics and Gynecology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand. ksrina@kku.ac.th
Anuwutnavin
Sanitra
S
Kanpittaya
Jaturat
J
Soontrapa
Sugree
S
Sakondhavat
Chuanchum
C
D001940:Breast / Q000187:drug effects*; D015331:Cohort Studies; D004338:Drug Combinations; D015914:Estrogen Replacement Therapy / Q000009:adverse effects*; D004967:Estrogens / Q000494:pharmacology*; D005260:Female; D006801:Humans; D008327:Mammography / Q000706:statistics & numerical data*; D008875:Middle Aged; D017698:Postmenopause / Q000187:drug effects*; D011372:Progestins / Q000494:pharmacology*; D013785:Thailand
D004338:Drug Combinations; D004967:Estrogens; D011372:Progestins