What's new in hormone replacement therapy: focus on transdermal estradiol and micronized progesterone

Abstract

The original conclusions of the Women's Health Initiative study have been questioned as a result of the availability of age-stratified data. Initial concerns regarding the risk of coronary heart disease (CHD) in association with the use of hormone replacement therapy (HRT) have been replaced with concerns regarding thromboembolic disease, encompassing venous thromboembolism (VTE), particularly in younger postmenopausal women, and stroke, particularly in older women. The original publication of the study results led to a dramatic decrease in the use of oral HRT; however, the use of transdermal HRT has increased over recent years. Guidelines from the North American Menopause Society, the Endocrine Society, the International Menopause Society, and specific guidelines from the European Menopause and Andropause Society for the management of menopausal women with a personal or family history of VTE all contain positive statements regarding both transdermal estradiol and micronized progesterone. Unlike oral estrogens, transdermal estradiol has been shown not to increase the risk of VTE, or stroke (doses ≤ 50 μg), and to confer a significantly lower risk for gallbladder disease. Unlike some progestogens, progesterone is also not associated with an increased risk of VTE, or with an increased risk of breast cancer. Based on these data, which are now included in the guidelines, the use of transdermal estradiol and micronized progesterone could reduce or possibly even negate the excess risk of VTE, stroke, cholecystitis, and possibly even breast cancer associated with oral HRT use.

Key words::

• ADVERSE EVENTS
• GUIDELINES
• HORMONE REPLACEMENT THERAPY
• THROMBOEMBOLIC DISEASE
• MICRONIZED PROGESTERONE
• TRANSDERMAL ESTRADIOL
• VENOUS THROMBOEMBOLISM

ACKNOWLEDGEMENTs

Assistance with writing this manuscript was provided by Clare Ryles, medical writer, and funded by Besins Healthcare. As this article was going to press, the North American Menopause Society (NAMS) released a new version of their position statement³⁸. This statement is consistent with and extends the information summarized in this manuscript.

Conflict of interest Dr J. A. Simon has served as a consultant or on the advisory boards of: Abbott Laboratories, Agile Therapeutics, Inc., Amgen Inc., Ascend Therapeutics, Azur Pharma, Inc., Biosante, Boehringer Ingelheim, Depomed, Inc., Fabre-Kramer, Laboratoire HRA Pharma, Meditrina Pharmaceuticals, Merck, Merrion Pharmaceuticals, NDA Partners LLC, Novo Nordisk, Novogyne, Pfizer Inc., Shionogi Inc., Slate Pharmaceuticals Inc., Teva Pharmaceutical Industries Ltd, Trovis Pharmaceuticals, LLC, Warner Chilcott, and Watson Pharmaceutical Inc. He has received grant/research support from BioSante, Boehringer Ingelheim, EndoCeutics Inc., Novo Nordisk, Novogyne, and Teva Pharmaceutical Industries Ltd. He has also served on the speakers’ bureaus of: Amgen Inc., Ascend Therapeutics, Bayer, Boehringer Ingelheim, Merck, Novartis, Novo Nordisk, Novogyne, Teva Pharmaceutical Industries Ltd, and Warner Chilcott.

Source of funding The content of this article was based on a presentation given at a symposium, sponsored by Besins Healthcare, at the 2011 World Congress on Menopause of the International Menopause Society.