A second bone mineral density (BMD) assessment about three years after initial measurement does not improve discrimination beyond baseline BMD value alone for women who do and do not experience subsequent hip fracture or major osteoporotic fracture, according to a study published online July 27 in JAMA Internal Medicine.

Carolyn J. Crandall, M.D., from the University of California in Los Angeles, and colleagues examined whether a second BMD measurement about three years after initial assessment is associated with improved ability to estimate fracture risk. The cohort study included 7,419 women from the Women’s Health Initiative, with mean follow-up of 12.1 years between 1993 and 2010.

The researchers found that 139 women (1.9 percent) experienced hip fractures and 732 (9.9 percent) experienced major osteoporotic fractures during a mean follow-up of nine years after the second BMD measurement. The area under the receiver operating characteristic curve (AU-ROC) values were 0.71, 0.61, and 0.73 for baseline total hip BMD, change in total hip BMD, and the combination of baseline total hip BMD and change in total hip BMD, respectively, in discriminating women who experienced hip fractures from those who do not. For discrimination of major osteoporotic fractures, the corresponding AU-ROC values were 0.61, 0.53, and 0.61.

“Thus, our evidence suggests that repeated BMD testing three years after baseline BMD in postmenopausal women should not be routinely performed,” the authors write.

Several authors disclosed financial ties to the biopharmaceutical industry.