Single-site vs multisite bone density measurement for fracture prediction.

Area of Science:

• Osteoporosis Research
• Geriatric Medicine
• Radiology

Background:

• Dual-energy x-ray absorptiometry (DXA) is standard for assessing bone density and fracture risk.
• Discordance between DXA measurements at different skeletal sites is common.
• The impact of measurement site discordance on fracture prediction remains unclear.

Purpose of the Study:

• To investigate how bone density measurements from different sites affect fracture prediction.
• To determine the optimal skeletal site for bone density measurement in fracture risk assessment.

Main Methods:

• A historical cohort study of 16,505 women aged 50+ was conducted.
• Data from Manitoba, Canada's DXA registry was used, with a mean follow-up of 3.2 years.
• Cox proportional hazards models assessed fracture prediction using single vs. combined DXA sites.

Main Results:

• Bone density at the total hip (HR, 1.85) and femur neck (HR, 1.77) showed stronger associations with osteoporotic fractures than the lumbar spine (HR, 1.61).
• Using the minimum bone density measurement did not improve fracture prediction compared to hip measurement alone.
• Including total hip measurements in predictive models rendered other sites largely redundant for overall fracture prediction.

Conclusions:

• Proximal femur bone density measurements, particularly the total hip, are superior to lumbar spine measurements for predicting overall fractures.
• The total hip is identified as the optimal site for comprehensive fracture risk assessment in this cohort.