Relationship between areal BMD, FRAX®, and femoral strength in community-dwelling older Asian adults

Summary T-scores alone are inadequate for identifying hip fracture risk. Incorporating FRAX-HFP scores and femoral strength improves risk assessment. Tailored interventions are needed for different ethnicities, with a focus on females due to higher fracture risk. Sex-specific thresholds and targeted prevention strategies are essential for effective fracture prevention.

Background We investigated the age-related trajectories of areal bone mineral density (aBMD), fracture risk assessment tool (FRAX)–based 10-year probability of hip fracture (FRAX-HFP), trochanteric soft tissue thickness (TSTT), and femoral strength in a multi-ethnic cohort of community-dwelling older adults in Singapore. We also examined the relationship between FRAX-HFP and femoral strength.

Methods Dual-energy X-ray absorptiometry (DXA) scans were conducted for Singaporean older adults (n = 2235), enrolled in the Population Health and Eye Disease Profile in Elderly Singaporeans (PIONEER) study. aBMD and FRAX-HFP were recorded for the subjects. TSTT was derived from whole-body DXA scans. Femoral strength was derived from DXA-based 3D finite element models. Age-related trajectories were compared for three major ethnicities in Singapore. The relationship between FRAX-HFP and femoral strength was examined.

Results The study included 2204 older adults (1224 females (73.71 ± 8.37 years), 980 males (73.45 ± 8.34 years)). Age-related trajectories for aBMD, FRAX-HFP, TSTT, and femoral strength indicated that Chinese ethnicity is at high risk for fracture, compared to Indians and Malays. Separately, FRAX-HFP identified 16% of males and 27% of females, and femoral strength identified 3% of males and 1% of females at risk. Both FRAX-HFP score and femoral strength identified 24% of males and 35% of females at risk.

Conclusion Age-related trajectories for aBMD, FRAX-HFP, TSTT, and femoral strength were found to be consistent with the hip fracture trends in Singapore. FRAX-HFP and femoral strength identified different individuals at risk, indicating that each, either alone or combined with aBMD, could improve the ability to assess hip fracture risk.