WHO Collaborating Centre for Metabolic Bone Diseases, University of Sheffield Medical School, Beech Hill Road, Sheffield, S10 2RX, UK.
Osteoporos Int. 2009 Oct;20(10):1675-82. doi: 10.1007/s00198-009-0845-x. Epub 2009 Mar 17.
This study examined the effects of the use of clinical risk factors (CRFs) alone, BMD alone or the combination using the FRAX tool for the detection of women at risk of hip fracture. BMD tests alone selected women at higher risk and a greater number of hip fracture cases were identified compared to the use of CRFs alone. The combined use of CRFs and BMD identified fewer women above a threshold risk than the use of BMD alone, but with a higher hip fracture risk and thus had the more favourable positive predictive value (PPV) and number needed to treat (NNT).
Algorithms have recently become available for the calculation of hip fracture probability from CRFs with and without information on femoral neck BMD. The aim of this study was to examine the effects of the use of CRFs alone, BMD alone or their combination using the FRAX tool for the detection of women at risk of hip fracture.
Data from 10 prospective population based cohorts, in which BMD and CRFs were documented, were used to compute the 10-year probabilities of hip fracture calibrated to the fracture and death hazards of the UK. The effects of the use of BMD tests were examined in simulations where BMD tests were used alone, CRFs alone or their combined use. The base case examined the effects in women at the age of 65 years. The principal outcome measures were the number of women identified above an intervention threshold, the number of hip fracture cases that would be identified, the positive predicted value and the NNT to prevent a hip fracture during a hypothetical treatment with an effectiveness of 35% targeted to those above the threshold fracture risk. We also examined BMD values in women selected for treatment. Sensitivity analysis examined the effect of age and limited use of BMD resources.
BMD tests alone selected women at higher risk of hip fracture than the use of CRFs alone (6.1% versus 5.3%). BMD tests alone also identified a greater number of hip fracture cases (219/1,000) compared to the use of CRFs alone (140/1,000). The combined use of CRFs and BMD identified fewer women above a threshold risk than the use of BMD alone (168/1,000 versus 219/1,000, respectively), but with a higher hip fracture risk (PPV, 8.6% versus 6.1%), and consequently a lower number needed to treat (NNT) (33 versus 47). In sensitivity analyses, the PPV and NNT were always better for the combination than either BMD or CRFs alone across all ages studied (50-70 years).
The use of FRAX in combination with BMD increases the performance characteristics of fracture risk assessment.
本研究旨在探讨仅使用临床风险因素（CRFs）、骨密度（BMD）或使用 FRAX 工具组合使用这两种方法检测髋部骨折风险的女性。与仅使用 CRFs 相比，BMD 测试单独选择了更高风险的女性，并且确定了更多的髋部骨折病例。与仅使用 BMD 相比，使用 CRFs 和 BMD 的组合确定了低于阈值风险的女性人数较少，但髋部骨折风险更高，因此具有更高的阳性预测值（PPV）和需要治疗的人数（NNT）。
最近，已经有算法可用于根据 CRFs 计算伴有和不伴有股骨颈 BMD 信息的髋部骨折概率。本研究的目的是探讨仅使用 CRFs、BMD 或使用 FRAX 工具组合使用这两种方法检测髋部骨折风险的效果。
使用来自 10 个前瞻性人群队列的数据，其中记录了 BMD 和 CRFs，用于计算经过 UK 骨折和死亡风险校准的 10 年髋部骨折概率。通过模拟检验仅使用 BMD 测试、CRFs 或组合使用这两种方法的效果。基础案例研究了在 65 岁女性中使用的效果。主要的观察指标是确定干预阈值以上的女性人数、将确定的髋部骨折病例数、阳性预测值和 NNT，以在针对高于阈值骨折风险的 35%的假设治疗中预防髋部骨折。我们还检查了为治疗而选择的女性的 BMD 值。敏感性分析检验了年龄和有限使用 BMD 资源的影响。
与仅使用 CRFs 相比，BMD 测试单独选择髋部骨折风险更高的女性（6.1%对 5.3%）。与仅使用 CRFs 相比，BMD 测试单独确定了更多的髋部骨折病例（219/1000）。与单独使用 BMD 相比，CRFs 和 BMD 的联合使用确定了较少的处于阈值风险以上的女性（分别为 168/1000 与 219/1000），但髋部骨折风险更高（PPV，8.6%对 6.1%），因此需要治疗的人数（NNT）更少（33 对 47）。在敏感性分析中，在所有研究年龄（50-70 岁）中，与单独使用 BMD 或 CRFs 相比，FRAX 联合使用的 PPV 和 NNT 始终更好。
FRAX 与 BMD 联合使用可提高骨折风险评估的性能特征。
