Many women whose bones test normal at age 65 can safely wait as long as 15 years before having a second bone density test, says a New York Times article based on a study published today in NEJM.
The researchers studied 4,957 women, 67 years of age or older, with normal bone mineral density (BMD) or osteopenia and no history of hip or clinical vertebral fracture or of treatment for osteoporosis. At 15 years, fewer than 1% of women with normal bone density when they entered the study, and fewer than 5% with osteopenia, developed osteoporosis in the following 15 years. The researchers report that osteoporosis would develop in less than 10% of older, postmenopausal women during rescreening intervals of approximately 15 years for women with normal bone density or mild osteopenia, 5 years for women with moderate osteopenia, and 1 year for women with advanced osteopenia.
According to the Times, bone density screening became popular after Fosamax, the first bisphosphonate, was approved in the mid 1990s. Physicians were "overly enthusiastic" in prescribing it for women whose bone density was "lower than normal but not in a danger zone, keeping women on the drug indefinitely." Now they are more likely to prescribe bisphosphonates for older patients and recommend against them for most younger postmenopausal women with osteopenia.
The study is expected to change the way physicians think about bone density screening, the Times says.