The New York Times reports, “Bone loss and osteoporosis develop so slowly in most women whose bones test normal at age 65 that many can safely wait as long as 15 years before having a second bone density test,” according to a study in the New England Journal of Medicine.
After following “nearly 5,000 women ages 67 and older for more than a decade,” researchers found that “fewer than one percent of women with normal bone density when they entered the study, and fewer than five percent with mildly low bone density, developed osteoporosis in the ensuing 15 years. But of those with substantially low bone density at the study’s start …10 percent progressed to osteoporosis in about a year.”
Separately, author Paula Span writes in the New York Times “The New Old Age” blog, “Medicare will cover DXA testing (it stands for dual-energy X-ray absorptiometry, if you must know) of the hip and spine every two years, but that may be much more frequently than many women require, and not often enough for others. … Without the first screening to assess your bone density, there’s no way to tell.” Span expresses concern that many women don’t get such an “initial bone mass measurement” because “doctors don’t think about it” and patients “aren’t asking for it.”
The AP reports that lead researcher “Dr. Margaret Gourlay, of the University of North Carolina,” noted that “the 15-year interval applies only to postmenopausal women judged to be at low risk for osteoporosis from the first screening … and perhaps fewer than half of US women over 65 fall into that category. But she said even for those women, other risk factors have to be considered: smoking, slim build, prior broken bones and taking medication that has an eroding effect on bones.”
The NPR “Shots” blog reports that while some experts believe the results will lead to reduced “health care spending on bone density scans,” Gourlay disagreed, pointing “out that only 13 percent of Medicare-eligible women get a bone density scan in a given year – a sign that many aren’t getting the baseline test that would inform their doctors what risk category they’re in, and thus how often they should get a repeat scan.”
Focusing on criticism of the study, WebMD reports, “An interval of 15 years is too long, says Felicia Cosman, MD, senior clinical director for the National Osteoporosis Foundation, who reviewed the study for WebMD” but was not involved in the research.
Cosman expressed concern that “this study is only a few thousand, and there are some inherent biases in the way the study was done,” such as “excluding those with a history of fractures.”
Instead of fifteen years, Cosman suggests that “women with moderate osteopenia … should be re-tested in two years.”