Women may get unneeded osteoporosis screening

By Amy Norton

NEW YORK (Reuters Health) - Many women who get screened for the bone-thinning disease osteoporosis may not actually need such testing, a new study suggests.

A number of expert guidelines say that women age 65 or older should get a bone scan to screen for osteoporosis, a condition in which bones become fragile and vulnerable to breaks. Some women with risk factors for osteoporosis, such as smoking, are advised to start screening around age 50.

But in the new study, researchers found that of 615 women who underwent osteoporosis screening at Connecticut clinics, 41 percent did not meet those criteria.

Exactly why they were tested is not clear from the study, according to lead researcher Dr. Peter F. Schnatz, of the Reading Hospital and Medical Center in Pennsylvania.

In some cases, women might ask for screening, he told Reuters Health. Or some doctors may not be aware of the guidelines and believe, for example, that it's best to screen all postmenopausal women.

Whatever the reasons, "the findings are certainly not encouraging," Schnatz said.

That's because like most screening, testing for osteoporosis has downsides.

Screening is usually done with a special type of x-ray that measures bone density, known as dual-energy X-ray absorptiometry (DXA). While the bone scan is simple and non-invasive, it is not cheap -- typically ringing up at $200 to $300.

More importantly, Schnatz said, unwarranted DXA screening may lead to some women being treated unnecessarily.

After the test, a woman is given a "T-score," which is a comparison of her bone mass against the average bone mass of a healthy, young woman. In some cases, a woman may have relatively low bone mass, though not overt osteoporosis, and the doctor may feel "compelled to treat," Schnatz said.

Treatment may include bisphosphonate medications like Fosamax, hormones or the drug Evista, which mimics the beneficial effects of estrogen on bone.

Those therapies can carry side effects -- including serious, though uncommon, risks like increased odds of stroke, breast cancer, and heart disease in women taking estrogen, and blood clots in those using Evista, according to past research. Bisphosphonates have been linked to rare cases of thigh bone fractures and bone death of the jaw.

The current findings, reported in the journal Menopause, are based on 615 women who underwent DXA screening in the Hartford, Connecticut, area.

Schnatz and his colleagues determined how many of those women met screening guidelines issued in 2006 by the North American Menopause Society (NAMS).

Those guidelines recommend DXA screening for all women age 65 and up. Women ages 50 to 64 may be candidates if they have certain risk factors for osteoporosis -- including smoking, a history of a "fragility" fracture since going through menopause, low body weight (under 127 pounds) and having a parent who suffered a hip fracture.

In 2010, NAMS added daily alcohol consumption and rheumatoid arthritis to its list of risk factors that should prompt earlier screening.

The guidelines are in line with those from other medical groups, like the American College of Obstetricians and Gynecologists.