Are Changes in Serial DXA Scans Reliable Indicators of Fracture Risk?

HealthDay News – Interval changes in bone mineral density (BMD) detected by dual-energy x-ray absorptiometry (DXA) are associated with fracture risk in women starting osteoporosis treatment. These results were recently published online July 19 in the Annals of Internal Medicine.

William D. Leslie, MD, from the University of Manitoba in Winnipeg, Canada, and colleagues examined repeated BMD testing as an indicator of treatment-related fracture risk reduction in a registry-based cohort study. Data were included for 6,629 women aged 40 years or older initiating osteoporosis treatment with two consecutive dual-energy X-ray absorptiometry scans.

The researchers found that 13.7% of women (910 women) developed incident fractures during a mean of 9.2 years, including 198 hip fractures. Women with a detectable decrease in total hip BMD had an absolute increase of 2.9% and 5.5% in the 5- and 10-year cumulative incidence of any fracture, respectively, compared with stable BMD, after adjustment for baseline fracture probability. 

For women with a detectable increase in total hip BMD, the risk for any fracture was 1.3% and 2.6% lower after 5 and 10 years, respectively. The results were consistent for change in femoral neck and lumbar spine BMD and across subgroup analyses.

Summary and Clinical Applicability

Interval changes in total hip BMD were associated with corresponding changes in fracture risk. 

“Treatment-related increases in total hip BMD are associated with reduced fracture risk compared with stable BMD, whereas decreases in BMD are associated with greater risk for fractures..monitoring BMD in clinical practice may help to identify women with a suboptimal response to osteoporosis treatment,” the researchers wrote.

Limitations and Disclosures

BMD testing intervals were not standardized across patients evaluated. 

Reference

1. Leslie WD, Majumdar SR, Morin SN, Lix LM. Change in Bone Mineral Density Is an Indicator of Treatment-Related Antifracture Effect in Routine Clinical Practice: A Registry-Based Cohort Study. Ann Intern Med. 2016. doi:10.7326/M15-2937.
   

This article originally appeared on MPR