MONDAY, May 1, 2006 (HealthDay News) -- Older men who have below normal levels of estrogen are at heightened risk for hip fractures, and those with low levels of both estrogen and testosterone are at even greater risk, a new study found.
Although there's no current tests for estrogen levels in men, experts believe that one day there may be treatments for low levels of the hormone. Until then, men who have lost bone mass should take calcium and vitamin D supplements to help reverse bone loss and reduce the risk of hip fractures, the researchers said.
The findings appear in the May issue of the American Journal of Medicine.
"Only in the last few years have we come to realize that low estrogen is important for men and their bone health," said lead researcher Dr. Shreyasee Amin, a rheumatologist at the Mayo Clinic. "Low estrogen levels affect about 15 percent of the male population," she added.
"The reason hip fracture is important is because of the high morbidity and mortality associated with it," Amin said. After a hip fracture, as many as 50 percent of men require institutionalized care. And up to 37 percent will die within one year of a hip fracture.
Although many people tend to associate testosterone with men and estrogen with women, men and women possess both hormones.
In its study, Amin's group collected data on 793 men whose estrogen and testosterone levels were measured between 1981 and 1983. The men were then followed until 1999. During the study period, 39 of the men had hip fractures resulting from a fall.
Amin's team found that men with low estrogen levels (below 18 picograms per milliliter) had a 3.1 times increased risk of hip fracture, compared with men who had higher estrogen levels.
While there was no significant increase in the risk for hip fracture among men with low testosterone levels alone, men with both low estrogen and low testosterone levels had a 6.5 times greater risk of hip fracture, compared with men who had high or mid-range levels of estrogen and testosterone levels, the researchers found.
Right now, not enough is known to recommend that men with low estrogen levels receive estrogen supplementation, Amin said. "There are hormones that are being used in women called selective estrogen receptor modulators that may be a potential option for these men, but it still needs to be studied," she said.
Men with low estrogen levels may need to start taking calcium and vitamin D supplements and possibly other medications, she said.
One expert agrees that estrogen levels are important for men's bone health.
"This is an interesting paper and tends to confirm that among men, estradiol [estrogen] levels may be more important to bone strength than is testosterone," said Dr. Stephen Honig, director of the Osteoporosis Center at the Hospital for Joint Diseases, in New York City.
Previous studies have linked low estrogen levels to low bone density as well as to a higher rate of spine fractures. But this is the first study suggesting that hip-fracture rates are higher among men with the lowest estrogen levels, he said.
"It may be reasonable to measure these hormones in elderly men, particularly those with low bone density values, but treating it is another story," Honig said. "This may give support to a trial of selective estrogen receptor modulator drugs in men to see if such an approach can reduce the incidence of hip fractures in elderly men at high risk for such fractures."
Another expert believes that testing estrogen levels in older men can be useful in assessing the risk of hip fractures.
"The more that we understand what's going wrong in these people, the better able we are going to be to do something about it," said Dr. Robert P. Heaney, a professor of medicine at the Osteoporosis Research Center at Creighton University.
The American College of Rheumatology can tell you more about osteoporosis.