Bone mineral density testing: How often?
A study suggests that many older women don't need frequent testing.
Bone mineral density (BMD) testing assesses bone strength and is one of the most important factors considered in evaluating a woman's risk for an osteoporotic fracture. Current screening guidelines recommend BMD testing at the hip and spine with dual-energy x-ray absorptiometry (DXA) for all women ages 65 and over — and earlier in women whose 10-year risk of fracture is 9.3% or greater. (You can calculate your 10-year fracture risk with the Fracture Risk Assessment Tool, or FRAX, at www.shef.ac.uk/FRAX. FRAX takes into account several risk factors in addition to BMD.) But until recently, there's been little scientific evidence on how often a woman should be screened.
In 2008, the long-term Study of Osteoporotic Fractures found that a repeat BMD test after eight years was no more helpful in predicting new fractures than the original measurement. Now, findings from that study indicate that older, postmenopausal women with normal bone density or mild osteopenia may not need a second scan for at least 15 years. (Osteopenia is bone mass that's lower than normal but not full-blown osteoporosis.)