Earlier this month, a statistical analysis of 23 different medical trials concluded that hormone replacement therapy (HRT) can reduce the risk of heart attacks in women by about a third. However, this is only true if the treatment is started before age 60. If the treatment is started after age 60, the risk of heart attacks actually increases during the first year of treatment.
Because of the impact of age on the effects of HRT, earlier studies that failed to take age into account, such as the Women’s Health Initiative, found that HRT actually increased the risk of women having heart attacks. Prof. Emeritus Edwin Salpeter, the J.G. White Distinguished Professor of Physical Sciences, who was the head statistician of this study, described the problem.
“The average age of women in the largest HRT study was well over 60 at the beginning of the study,” Salpeter said. “Women who should decide about the treatment should be closer to 50 than 65.”
However, the data from that study was still useful to the analysis. Data on the women who were part of the WHI study was combined with that from other studies giving the researchers information about over 39,000 women. Pooling the different studies was essential. Although smaller studies done since the WHI separated results by age, “no one study alone could give you an answer,” Salpeter said.
Hormone replacement therapy is designed to counteract the effects of menopause that occur when there is a drop in the levels of circulating estrogen hormones in the blood. According to Salpeter, the big question in the future will be about alternative types of therapy.
“The American version is different from the European version, and treatment can be done transdermally, with patches,” he said. He has “a slight hunch,” that both the good and bad effects of HRT will be diminished with lower dosages.
This study was done by researchers from both Stanford and Cornell. The lead author of the study was Salpeter’s daughter, Prof. Shelley Salpeter, medicine, Stanford University School of Medicine. Salpeter described the experience of working with family as “great fun.” However, he did have a few adjustments to make. Salpeter said, “With astrophysics, I was working on my own, or the senior partner. Here, I’m the statistician, she’s the medical doctor, clearly she’s in charge.”
A good deal of the work was done in Shelley’s home office, as neither father nor daughter received any financial grant for their work.
“We think it’s important to not take funding from pharmaceutical companies,” Salpeter said. He explained that there have been papers done showing that researchers are likely to be biased if they receive funding from a company, even if they are not directly employed by that company. He added that the phenomenon of indirect influence “is not fully understood.”
Although this study is significant, it should be only one element of a woman’s decision to undergo HRT.
“You shouldn’t think in terms of heart disease alone,” Salpeter explained. “There are other factors, like cancer. HRT increases the risk of breast cancer, but decreases the risk of colorectal cancer.” It is essential for women to take into account their own personal and family health history to weigh the risks.
According to Salpeter, “The most important advice is that each woman should consult with her doctor.”
Archived article by Laura Rice
Sun Staff Writer