Review on December 03, 2009
Estrogen hormones have been a popularly-used supplement in relieving menopausal symptoms such as hot flashes since the 1940s. Besides hot flashes, estrogen has also been used by women to prevent chronic diseases such as cardiovascular disease and osteoporosis. Since 2002 estrogen use has declined following data from the Women's Health Initiative (WHI), which showed that women using conjugated equine estrogen hormones (CEE) and medroxyprogesterone acetate to treat hot flashes and other menopause symptoms were at increased risk of coronary heart disease, strokes, and breast cancer compared to females taking placebo. Because the Women's Health Initiative suggested that estrogen was harmful in terms of disease prevention, proposals for postmenopausal hormone therapy have been changed. Yet, low-dose estrogen hormone use for treating menopausal hot flashes is still accepted. This review looks at 32 treatment trials and compares the effectiveness and safety of the most widely-used estrogen hormones preparations in alleviating menopausal hot flashes.
Following data from the WHI, The US Food and Drug Administration recently called for estrogen hormones safety advice to be included on packaging and changed approved indications for its use. Package information shows that treating hot flashes and other menopausal symptoms is a suggested use for estrogen hormones but nowadays doctors are advised to use the smallest feasible dose for the shortest length of time possible.
There are numerous estrogen hormones preparations available for alleviating hot flashes, including oral, transdermal, and topical forms. A comparison of different estrogen hormones agents to treat hot flashes is necessary due to concerns about CEE raised in the WHI study. Disparities between agents and routes have been outlined but it is unclear whether or not such differences result in significant clinical effects.
With regard to measuring hot flashes in the estrogen hormones trials, women were usually asked to note down the number of hot flashes occurring over a daily or weekly period, and changes denoted treatment responses.
Results from the trials included in this review suggest that CEE and oral and transdermal 17 -estradiol are more successful than placebo in relieving menopausal hot flashes, and findings do not show that one is more efficient than another. Different doses can be effective, although a dose-response connection was reported in a few analyses. Very few trials have focused on estrogen hormones other than CEE and 17 -estradiol, thus it is not possible to assess their comparative success.
Such results are in keeping with a Cochrane review and meta-analysis of trials of oral estrogen hormones compared with placebo for relieving menopausal hot flashes, published prior to 2000. Findings suggested a 77% reduction in regularity and a considerable decrease in severity of hot flashes with oral estrogen hormones compared with placebo.
Conclusion 1: The above findings show that CEE and oral and transdermal 17 -estradiol have reliable, positive effects on treating hot flashes but may also produce undesirable effects. It can be concluded that further exploration is needed; for example effects on a larger demographic sample of women, longer follow-up, more patients, and more head-to-head comparisons of estrogen hormones, progestins or progesterones, and other therapies. Studying such factors to a greater extent would result in better information about personal estrogen hormones use for treating hot flashes, including which women would benefit from this treatment and any possible side effects, and establishing when and how best to stop therapy. As very few trials have focused on estrogen hormones apart from CEE and 17 -estradiol, it is not possible to assess their relative effectiveness in treating hot flashes.