Bone Up on Hormone Replacement Therapy
"This does not in any way change my mind about the potential benefits of HRT or estrogen in preventing fractures," says Recker, who is director of the Osteoporosis Research Center at Creighton University School of Medicine in Omaha, Neb. He says that many other studies have shown that HRT increases bone mass and that a few studies have shown that the therapy also can reduce the risk of fractures.
Recker says in addition to those, other studies suggest that the estrogenlike drug raloxifene, which is sold as Evista, is very effective at reducing the risk of spine fractures. Since estrogen and Evista work similarly, he says there's no reason to believe that estrogen would be any less effective at reducing fractures when taken for five years or more.
The biggest problem, he says, is that almost no studies have looked at postmenopausal women long enough to determine whether estrogen or estrogen plus progestin leads to fewer fractures as they age. One ongoing study -- the Women's Health Initiative -- is attempting to do this, but it is not scheduled to be completed until 2004.
"We just have to wait. I think the evidence is pretty clear that estrogen will slow or prevent bone loss. Now, whether over the years that will translate into fracture reduction, nobody knows," says C. Conrad Johnston Jr., MD, president of the board of trustees of the National Osteoporosis Foundation and a professor of medicine at Indiana University School of Medicine in Indianapolis. "But the evidence suggests that the earlier you take it, the more of an effect it will have."
Johnston says his advice to women wondering about whether to start or continue taking hormones to prevent fractures is, "don't throw the baby out with the bathwater" based on this study alone.
According to the National Osteoporosis Foundation, 8 million women in the U.S. have osteoporosis, which puts them at significantly increased risk for bone fractures as they age. Another 14.4 million women have low bone mass, which also increases the risk of fractures.