The Women's Health Initiative (WHI) is a long-term national health study focused on strategies for preventing heart disease, breast and colorectal cancer, and osteoporotic fractures in postmenopausal women. Launched in 1993, the WHI enrolled 161,808 women aged 50-79 into one or more randomized Clinical Trials (CT), testing the health effects of hormone therapy (HT), dietary modification (DM), and/or
calcium and Vitamin D supplementation (CaD) or to an
Observational Study (OS). At the end of the initial study period in 2005, WHI Extension Studies (2005-2010,
2010-2020) continued follow-up of all women who consented.
This ground-breaking study changed the way health care providers prevent and treat some of the major diseases impacting postmenopausal women. Results from the WHI Hormone Trials have been estimated to have already saved $35.2 billion in direct medical costs in the US alone. To date, WHI has published over 1,400
articles and approved and funded 289 ancillary studies.
Interested scientists are encouraged to submit paper and ancillary study proposals for using WHI data. To assist in this, this website includes an
overview of WHI,
study documentation, and information on how to
submit a paper or
ancillary study proposal.
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Carolyn J. Crandall, MD, MS, FACP, Professor of Medicine at the David Geffen School of Medicine at University of California, Los Angeles received the best paper of the year award from the journal Menopause. The award was announced at the North American Menopause Society Annual Meeting in September 2019.
The paper found that after menopause, up to half of women will experience symptoms of atrophic vaginitis. The symptoms of atrophic vaginitis include vaginal dryness, burning, and irritation, including pain with intercourse. These symptoms have negative effects on women's lives. There are many available preparations of vaginal estrogen therapies available to treat the symptoms of atrophic vaginitis. In this study, we examined data from 45,663 women in the WHI Observational Study to compare the occurrence of several important health outcomes among women using, versus women not using, vaginal estrogen therapy. We found that the risks of cardiovascular disease and cancer were not elevated among postmenopausal women using vaginal estrogen. These results are reassuring regarding the safety of these preparations.
Crandall CJ, Hovey KM, Andrews CA, Chlebowski RT, Stefanick ML, Lane DS, Shifren J, Chen C, Kaunitz AM, Cauley JA, Manson JE. Breast cancer, endometrial cancer, and cardiovascular events in participants who used vaginal estrogen in the WHI Observational Study. Menopause. 2018 Jan;25(1):11-20. doi: 10.1097/GME.0000000000000956. Epub 2017 Aug 14.
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