Could Multiple BMD Measurements Help Predict Fracture Risk?

Serial measurement of bone mineral density (BMD) does not improve accuracy when trying to distinguish between postmenopausal women who are and are not at increased risk of fracture, according to the results of a recent study.

“Repeated BMD testing to screen for osteoporosis requires resources,” the researchers wrote. “For patient counseling and optimal resource use, it is important for clinicians to know whether repeated BMD measurement (compared with baseline BMD measurement alone) improves the ability to discriminate between postmenopausal women who will and will not experience a fracture.

In order to determine whether a subsequent assessment of BMD 3 years after initial measurement could be beneficial for estimating fracture risk, they used data from 7419 women who participated in the Women’s Health Initiative Study, a prospective observational study involving 161,808 postmenopausal women in the US. In the current analysis, the mean age of participants was 66.1 (7.2) years, and mean body mass index was 28.7 (6.0).

Area under the receiver operating characteristic curve (AU-ROC) for baseline BMD, absolute change in BMD, and combination of baseline BMD and change in BMD were used to calculate fracture risk.

Overall, 139 of the women experienced hip fractures and 732 experienced major osteoporotic fractures. When discriminating between women with and without hip fractures, AU-ROC values were 0.71 (95% CI, 0.67-0.75) for baseline total hip BMD, 0.61 (95% CI, 0.56-0.65) for change in total hip BMD, and 0.73 (95% CI, 0.69-0.77) for the combination of baseline total hip BMD and change in total hip BMD. When discriminating between women with and without osteoporotic fracture, AU-ROC values were 0.61 (95% CI, 0.59-0.63) for baseline total hip BMD, 0.53 (95% CI, 0.51-0.55) for change in total hip BMD, and 0.61 (95% CI, 0.59-0.63) for the combination of baseline total hip BMD and change in total hip BMD.

“In this prospective study of a large cohort of postmenopausal women, compared with baseline BMD alone, change in BMD and the combination of change in BMD with baseline BMD did not have a better ability to discriminate women who experienced subsequent hip fracture or MOF from women who did not,” the researchers concluded.

“This information will inform future guidelines regarding the interval for repeated BMD testing in untreated postmenopausal women. Our findings further suggest that resources should be devoted to increasing the underuse of baseline BMD testing among women aged 65 and 85 years, one-quarter of whom do not receive an initial BMD test.”

—Michael Potts

Reference:

Cranall CJ, Larson J, Wright NC, et al. Serial bone density measurement and incident fracture risk discrimination in postmenopausal women. JAMA Intern Med. 2020;180(9):1232-1240. doi:10.1001/jamainternmed.2020.2986