The New England Journal of Medicine has just published a study of DXA results. The researchers have interpreted the results as a reason to stop testing women with DXA. The study was only about DXA, and only about a special group of women who are unlike the vast majority of women.
DXA alone is a very poor way to test for “Clinical Osteoporosis” (High Risk of Fracture), especially in the women 67 and older who were the only ones studied. Even worse, the question asked in the study was how quickly the DXA score changed in the few women of that age who still have good DXA scores. That question is not even relevant to Fracture Risk.
DXA is most useful much earlier in life than age 67. A woman should get her first DXA when she begins menopause (after the first missed period). A low DXA score then alerts her to possible impending danger if she loses bone mineral density rapidly during menopause. Some women lose more than 20% of their total bone mineral density during menopause.
Even those young women need far more than DXA alone to determine how to avoid fractures. So do all older women, like those over 67 in the study. Screening for the high fracture risk of “Clinical Osteoporosis” (as defined by NIH in 2001), requires a full evaluation. The researchers ignored that reality.
Jay Ginther, MD