Repeat bone mineral density tests during osteoporosis treatment may help identify women at increased fracture risk, study finds
Monitoring bone mineral density in routine clinical practice may identify women with a suboptimal response to osteoporosis treatment who would benefit from closer follow-up, researchers noted.
Continually monitoring bone mineral density (BMD) in female patients with osteoporosis may help physicians identify those most at risk for fracture, according to a recent study.
Researchers used population-based registries from Manitoba, Canada, to evaluate repeated BMD measurements (determined by dual-energy X-ray absorptiometry [DXA]) as a predictor of fracture risk in women undergoing treatment for osteoporosis. Results were published on July 19 by Annals of Internal Medicine.
Of 6,629 women ages 40 years or older (mean age, 64.3 years) who had baseline DXA measurements of the hip and/or lumbar spine after April 1, 1998, 57.2% met the BMD criterion for osteoporosis at 1 or more skeletal sites. Researchers identified patients with a follow-up DXA exam before March 31, 2013, and assessed change in total hip BMD (the site with the smallest measurement error) and fracture risk using the Canadian version of the World Health Organization Fracture Risk Assessment Tool.
During 61,088 person-years of follow-up, 910 (13.7%) women sustained 1 or more fractures. A detectable increase in BMD was more common than a detectable decrease, although the latter was seen in 1,526 (23.0%) women. Compared to stable total hip BMD, a detectable decrease in total hip BMD was associated with a greater risk for fracture (P<0.001), whereas a detectable increase was associated with lower risk for fracture (P=0.004). A detectable decrease in total hip BMD was also associated with a greater hip fracture risk (P<0.001), but there was no significant difference in risk associated with a detectable increase in this measure (P=0.167).
Compared to women with a stable total hip BMD, those with a detectable decrease had an absolute increase in the risk for any fracture (2.9% [95% CI, 1.5% to 4.4%] after 5 years and 5.5% [95% CI, 2.8% to 8.1%] after 10 years) and hip fracture (0.9% [95% CI, 0.4% to 1.5%] after 5 years and 2.8% [95% CI, 1.2% to 4.3%] after 10 years). Compared to those with stable total hip BMD, women with a detectable increase in total hip BMD had a 1.3% lower risk (95% CI, 0.4% to 2.2%) for any fracture after 5 years and a 2.6% (95% CI, 0.7% to 4.5%) lower risk after 10 years. Fracture risk results were generally consistent in subgroup analyses and when based on change in femoral neck and lumbar spine BMD.
The study authors noted limitations to their work, such as its observational nature and lack of a fixed BMD testing interval, as well as the inability to account for changes in clinical management that might have occurred after subsequent BMD tests. “Monitoring BMD in routine clinical practice may identify women with a suboptimal response to osteoporosis treatment who would benefit from closer follow-up, attention to secondary causes of osteoporosis, and directed inquiries about medication adherence and persistence,” they concluded.