Source: Gabriel Sanchez R, Sanchez Gomez LM, Carmona L, Roqué i Figuls M, Bonfill Cosp X. Hormone replacement therapy for preventing cardiovascular disease in post-menopausal women. Cochrane Database of Systematic Reviews 2005, Issue 2. Art. No.: CD002229
Efficacy Endpoints: Heart attack, stroke, death
Harm Endpoints: Heart attack, stroke, death, development of a blood clot
Narrative: Hormone replacement therapy ('HRT') was believed for many years to potentially restore cardiovascular hormonal balance for women after menopause, thus reducing heart attacks, strokes and death. While this therapy has been shown to reduce hot flashes,1 before the past ten years there were no major trial results to answer the question of whether or not HRT works to prevent heart problems and strokes.
This review examined the highest quality randomized trials that tested HRT for preventing heart attacks, strokes, and death, and included about 20000 subjects from a variety of trials. The results of these trials were very surprising for many scientists and physicians who had been recommending HRT for years, because HRT did not prevent deaths, and overall it did increase heart attacks and strokes among those who had never had a previous heart attack or stroke. It is also disturbing that blood clots in the legs and lungs were increased, although it is important to note that despite the increases in heart attacks, strokes, and blood clots there was no increase in deaths due to HRT.
Caveats: The results in this review come almost entirely from a single trial. This was a very large and well done trial, but whenever one trial is the only source for results there is the possibility that those involved in the trial may be slightly different than other populations. It would be reassuring to see another trial with a different group confirm these results, although for now these data seem good enough to use for decisions about whether to use HRT. It is also important to note however, that there are benefits of HRT as well, including reduced hot flashes and small reductions in colon cancer and fractures, and it may be worth integrating all of these in making a decision about whether or not HRT is right for a given patient.
Author: David Newman, MD
Published/Updated: July 8, 2011
The title bar is color-coded with our overall recommendation.
If you have suggestions, requests, or questions about a particular NNT review, please send us a message and we’ll try to address it as soon as possible.