The Women’s Health Initiative (WHI) randomized controlled trials included over 27,000 postmenopausal women between the ages of 50 and 79 who took estrogen and progestin, estrogen alone or a placebo. Led by Brian Walitt of Washington Hospital Center in Washington, DC, the current study identified women who had RA based on whether they reported having it and were taking prescription medications to treat it.
The study is the only placebo-controlled trial to evaluate the effect of hormone replacement therapy on developing RA and the sixth study to evaluate the effects of hormone therapy on how women perceive disease severity. The results showed that there were 105 new cases and 63 existing cases of RA. There were no statistically significant differences on either new RA cases over an average of five to six years or on the severity of RA symptoms after one year. While earlier studies had suggested that hormones had a protective effect against developing RA, they were observational. The current study found no significant protective benefit from hormones in preventing RA.
Although the prevalence of RA in the study was about half of what is found in the general population, this may be due to the tendency of clinical trials to recruit healthier patients and the exclusion of participants taking prednisone, which is used to treat arthritis. Although the WHI methodology has many advantages over prior studies, the sample size for RA was much less than what would be required to observe the effect of hormone replacement therapy on developing RA. However, it is unlikely that larger studies will be carried out, due to the health risks of hormone replacement therapy.
MEDICA.de; Source: Wiley-Blackwell