Moayyeri Alireza, Kaptoge Stephen, Dalzell Nichola, Bingham Sheila, Luben Robert N, Wareham Nicholas J, Reeve Jonathan, Khaw Kay Tee
Department of Public Health and Primary Care, Institute of Public Health, University of Cambridge, Cambridge, United Kingdom.
J Bone Miner Res. 2009 Jul;24(7):1319-25. doi: 10.1359/jbmr.090212.
Although quantitative ultrasound (QUS) is known to be correlated with BMD and bone structure, its long-term predictive power for fractures in comparison with DXA is unclear. We examined this in a sample of men and women in the European Prospective Investigation into Cancer (EPIC)-Norfolk who had both heel QUS and hip DXA between 1995 and 1997. From 1455 participants (703 men) 65-76 yr of age at baseline, 79 developed a fracture over 10.3 +/- 1.4 yr of follow-up. In a sex-stratified Cox proportional-hazard model including age, height, body mass index, prior fracture, smoking, alcohol intake, and total hip BMD, a 1 SD decrease in BMD was associated with a hazard ratio (HR) for fracture of 2.26 (95% CI: 1.74-2.95). In the multivariable model with heel broadband ultrasound attenuation (BUA) in place of BMD, HR for a 1 SD decrease in BUA was 2.04 (95% CI: 1.55-2.69). Global measures of model fit showed relative superiority of the BMD model, whereas the area under the receiving operator characteristic (ROC) curve was slightly higher for the BUA model. Using both Cox models with BMD and BUA measures, we calculated exact 10-yr absolute risk of fracture for all participants and categorized them in groups of <5%, 5% to <15%, and >or=15%. Comparison of groupings based on two models showed a total reclassification of 28.8% of participants, with the greatest reclassification (approximately 40%) among the intermediate- and high-risk groups. This study shows that the power of QUS for prediction of fractures among the elderly is at least comparable to that of DXA. Given the feasibility and lower cost of ultrasound measurement in primary care, further studies to develop and validate models for prediction of 10-yr risk of fracture using clinical risk factors and QUS are recommended.
尽管定量超声（QUS）与骨密度（BMD）和骨结构相关，但其与双能X线吸收法（DXA）相比对骨折的长期预测能力尚不清楚。我们在欧洲癌症前瞻性调查（EPIC）-诺福克研究中对1995年至1997年间同时进行足跟QUS和髋部DXA检查的男性和女性样本进行了研究。在基线时年龄为65 - 76岁的1455名参与者（703名男性）中，79人在10.3±1.4年的随访期间发生了骨折。在一个按性别分层的Cox比例风险模型中，该模型纳入了年龄、身高、体重指数、既往骨折史、吸烟、饮酒量和全髋骨密度，骨密度降低1个标准差与骨折风险比（HR）为2.26（95%置信区间：1.74 - 2.95）相关。在将足跟宽带超声衰减（BUA）代替骨密度的多变量模型中，BUA降低1个标准差的HR为2.04（95%置信区间：1.55 - 2.69）。模型拟合的整体指标显示骨密度模型具有相对优势，而接收者操作特征（ROC）曲线下面积在BUA模型中略高。使用包含骨密度和BUA测量值的两个Cox模型，我们计算了所有参与者确切的10年骨折绝对风险，并将他们分为<5%、5%至<15%以及≥15%的组。基于两个模型的分组比较显示，28.8%的参与者被重新分类，在中高风险组中重新分类比例最大（约40%）。这项研究表明，QUS对老年人骨折的预测能力至少与DXA相当。鉴于超声测量在初级保健中的可行性和较低成本，建议进一步开展研究以开发和验证使用临床风险因素和QUS预测10年骨折风险的模型。
