Hormone Replacement Therapy Research Today is a free monthly online journal that collates and summarizes the latest research about Hormone Replacement Therapy, including details on hrt, menopause, natural hrt, effects, risks.

Conjugated equine estrogens and breast cancer risk in the Women's Health Initiative clinical trial and observational study.

Prentice RL, Chlebowski RT, Stefanick ML, Manson JE, Langer RD, Pettinger M, Hendrix SL, Hubbell FA, Kooperberg C, Kuller LH, Lane DS, McTiernan A, O'Sullivan MJ, Rossouw JE, Anderson GL

Division of Public Health Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA 98109-1024, USA. rprentic@fhcrc.org

The Women's Health Initiative randomized controlled trial found a trend (p = 0.09) toward a lower breast cancer risk among women assigned to daily 0.625-mg conjugated equine estrogens (CEEs) compared with placebo, in contrast to an observational literature that mostly reports a moderate increase in risk with estrogen-alone preparations. In 1993-2004 at 40 US clinical centers, breast cancer hazard ratio estimates for this CEE regimen were compared between the Women's Health Initiative clinical trial and observational study toward understanding this apparent discrepancy and refining hazard ratio estimates. After control for prior use of postmenopausal hormone therapy and for confounding factors, CEE hazard ratio estimates were higher from the observational study compared with the clinical trial by 43% (p = 0.12). However, after additional control for time from menopause to first use of postmenopausal hormone therapy, the hazard ratios agreed closely between the two cohorts (p = 0.82). For women who begin use soon after menopause, combined analyses of clinical trial and observational study data do not provide clear evidence of either an overall reduction or an increase in breast cancer risk with CEEs, although hazard ratios appeared to be relatively higher among women having certain breast cancer risk factors or a low body mass index.

Published 9 June 2008 in Am J Epidemiol, 167(12): 1407-15.
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Articles on Hormone Replacement Therapy published 9 June 2008:

Invited commentary: Postmenopausal unopposed estrogen and breast cancer risk in the Women's Health Initiative--before and beyond.   Am J Epidemiol, 167(12): 1416-20.

Three large clinical trials provoked major debate when hormone replacement therapy (HRT) did not reduce coronary heart disease in postmenopausal women as expected from observational epidemiologic studies. Less discussion has ensued about breast cancer or other adverse events. In this issue of the Journal, investigators from the Women's Health Initiative (WHI) compare breast cancer findings from the randomized trial of unopposed estrogen with those from the large WHI observational study. This ... [Abstract] [Full-text]

Articles on Hormone Replacement Therapy published 30 May 2008:

Hormone replacement therapy and risk of venous thromboembolism in postmenopausal women: systematic review and meta-analysis.   BMJ, 336(7655): 1227-31.

OBJECTIVE: To assess the risk of venous thromboembolism in women using hormone replacement therapy by study design, characteristics of the therapy and venous thromboembolism, and clinical background. DESIGN: Systematic review and meta-analysis. DATA SOURCES: Medline. STUDIES REVIEWED: Eight observational studies and nine randomised controlled trials. INCLUSION CRITERIA: Studies on hormone replacement therapy that reported venous thromboembolism. REVIEW MEASURES: Homogeneity between studies was ... [Abstract] [Full-text]

Articles on Hormone Replacement Therapy published 23 May 2008:

Kidney dysfunction and sudden cardiac death among women with coronary heart disease.   Hypertension, 51(6): 1578-82.

We evaluated the association between kidney dysfunction and sudden cardiac death risk among ambulatory women with coronary heart disease. The Heart and Estrogen Replacement Study evaluated the effects of hormone treatment on cardiovascular events among 2763 postmenopausal women with coronary heart disease. Kidney dysfunction was categorized by estimated glomerular filtration rate (eGFR) using the Modification of Diet in Renal Disease equation. Multivariate proportional hazards models were used ... [Abstract] [Full-text]

Articles on Hormone Replacement Therapy published 14 May 2008:

Hormonal replacement therapy after menopause is protective of disease activity in women with inflammatory bowel disease.   Am J Gastroenterol, 103(5): 1193-6.

BACKGROUND AND AIMS: The nature of inflammatory bowel disease (IBD) following menopause has not been previously studied. The aim of this study was to characterize the effect of menopause on disease activity and identify possible modifiers of disease activity. METHODS: This was a retrospective study of women followed at the University of Chicago IBD Clinic. Disease activity was assessed using clinical scoring systems during the pre- and postmenstrual periods of subjects. Variables of interest ... [Abstract] [Full-text]

Articles on Hormone Replacement Therapy published 12 May 2008:

Estrogen plus progestin therapy and breast cancer in recently postmenopausal women.   Am J Epidemiol, 167(10): 1207-16.

The Women's Health Initiative trial found a modestly increased risk of invasive breast cancer with daily 0.625-mg conjugated equine estrogens plus 2.5-mg medroxyprogesterone acetate, with most evidence among women who had previously received postmenopausal hormone therapy. In comparison, observational studies mostly report a larger risk increase. To explain these patterns, the authors examined the effects of this regimen in relation to both prior hormone therapy and time from menopause to first ... [Abstract] [Full-text]

Articles on Hormone Replacement Therapy published 5 May 2008:

Postsurgical administration of estradiol benzoate decreases tensile strength of healing skin wounds in ovariectomized rats.   J Surg Res, 147(1): 117-22.

BACKGROUND: The most effective method of increasing the level of estrogen in the wounds of post-menopausal women undergoing routine surgical procedures is by long-term preoperative administration. However, in the case of acute surgery or trauma, the most effective method of increasing the level of estrogen is administration immediately pre- or postsurgery. This study, therefore, was aimed at assessing the effect of postsurgical administration of estradiol benzoate on wound healing in ... [Abstract] [Full-text]

Articles on Hormone Replacement Therapy published 28 April 2008:

Dietary boron and hormone replacement therapy as risk factors for lung cancer in women.   Am J Epidemiol, 167(9): 1070-80.

Hormone replacement therapy (HRT) may reduce lung cancer risk. Dietary boron may have actions similar to those of HRT; however, no previous study has reported the associations between dietary boron intake and lung cancer risk or the joint effects of boron intake and HRT use on lung cancer risk. The authors examined the associations between boron intake and the joint effects of boron intake and HRT on lung cancer risk in women. In an ongoing case-control study in Houston, Texas (July 1995 ... [Abstract] [Full-text]

Articles on Hormone Replacement Therapy published 18 April 2008:

Effects of estrogen on intracellular signaling pathways linked to activation of muscarinic acetylcholine receptors and on acetylcholinesterase activity in rat hippocampus.   Biochem Pharmacol, 75(9): 1827-34.

The aim of the present study was to investigate the effects of estrogen lack and estrogen replacement on the production of total [3H]inositol phosphate ([3H]IP) induced by the activation of muscarinic acetylcholine receptors (mAChRs) and on the mechanisms for inactivation of acetylcholine. Hippocampi were obtained from rats in proestrus (PE), ovariectomized for 15 days (C15), ovariectomized for 15 days and then treated with 17beta-estradiol for 7 days (E7) and ovariectomized and immediately ... [Abstract] [Full-text]

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