Physical performance measures, appendicular lean mass may predict incident fractures
Incident fractures may be predicted by physical performance and appendicular lean mass, independent of previous falls and FRAX probability, according to findings published in the Journal of Bone and Mineral Research.
“Although the predictive value of falls-related risk factors for incident fracture have been demonstrated individually, it has not been established whether the risk information so provided will be independent of that obtained through FRAX and [bone mineral density],” Nicholas C. Harvey, PhD, of NIHR Southampton Biomedical Research Centre, University of Southampton, and colleagues wrote in the study background. “This is an important consideration, because if these measures were to provide no additional information over and above current fracture risk assessment, then there would be little to be gained from their measurement as part of fracture risk stratification.”
In the meta-analysis, the researchers evaluated 10,411 men aged at least 65 years who could walk without assistance participating in the Osteoporotic Fractures in Men (MrOS) cohorts from Hong Kong (n = 1,987; mean age, 72 years; mean follow-up, 9.9 years), Sweden (n = 2,764; mean age, 75 years; mean follow-up, 8.7 years) and the United States (n = 5,660; mean age, 74 years; mean follow-up, 10.9 years). At baseline, participants completed a questionnaire that included fall history, underwent chair stand and grip strength tests and DXA scan for BMD and appendicular lean mass assessment. Researchers calculated 10-year probability for fracture with and without femoral neck BMD measurements using country-specific FRAX models and estimated the predictive value of four physical performance measures, independent of FRAX probability, history of falls, or BMD.
The three cohorts had similar rates of past falls (20% for U.S., 16% for Sweden and 15% for Hong Kong). Sweden had the highest mean FRAX probability (major osteoporotic fracture with BMD) (11.4%); followed by the USA (7.8%) and Hong Kong (6.6%). Greater time for five chair stands was correlated with higher major osteoporotic fracture risk across all cohorts (HR = 1.26; 95% CI, 1.19-1.34) whereas greater walking speed, grip strength and appendicular lean mass adjusted for body size were linked to reduced risk of incident major osteoporotic fracture (greater walking speed HR = 0.85; 95% CI, 0.79-0.9; grip strength HR = 0.77; 95% CI, 0.72-0.82; appendicular lean mass adjusted for body size HR = 0.85; 95% CI, 0.8-0.9). These associations largely persisted after adjustment for FRAX, but the correlation between appendicular lean mass adjusted for body size and major osteoporotic fractur was attenuated (HR =0.92; 95% CI, 0.85-0.99). An analysis including femoral neck BMD yielded a notable diminishment in the association between appendicular lean mass adjusted for body size and major osteoporotic fracture (HR = 1.02; 95% CI, 0.96-1.1).
“We have demonstrated that physical performance and appendicular lean mass are predictive of incident fracture, independently of prior falls and FRAX probability,” the researchers wrote. “The observation that inclusion of BMD in the models markedly attenuated the predictive value of appendicular lean mass requires further investigation to differentiate a true effect from artifact caused by the DXA technology.” – by Jennifer Byrne
Disclosures: The authors report no relevant financial disclosures.