The fracture predictive value of quantitative ultrasound (QUS) may be modified by previous fracture status. Non-significant associations between QUS parameters and fracture risk were observed among frail older people with a history of fracture. These findings suggest that QUS measurements for frail older people might be more useful in those without a fracture history.
Introduction: Quantitative ultrasound has been shown to predict risk of fracture in various populations. However, this ability may be modified by the presence of previous fracture in very frail older people.
Methods: We assessed bone strength by QUS and clinical risk factors at baseline for 1,982 institutionalised older people. Fractures were ascertained for 2 years from baseline and validated by X-ray reports.
Results: Study participants were very old (mean age = 85.7 +/- 7.1 years) and frail (70% using walking aids). Forty-five percent reported a history of fracture. During a mean follow-up period of 1.64 years, 335 participants suffered a fracture or fractures. Fracture rates were significantly higher in participants with a history of fracture compared with those without a history of fracture (16.0 vs 9.2 per 100 person years, p < 0.001). Significant associations between fracture risk and QUS parameters (broadband ultrasound attenuation and velocity of sound) were observed among participants without a history of fracture (both p < 0.01), but not among those who had a fracture history (both p >/= 0.7).
Conclusions: In very frail older people, QUS measurements may be more useful for assessing fracture risk in those without a history of fracture after age 50.