Praveen Anitha D, Jha Dheeraj, Baker Alexander, Fleps Ingmar, Björnsson Páll, Ellingsen Lotta María, Aspelund Thor, Sigurdsson Sigurdur, Gudnason Vilmundur, Pálsson Halldór, Matchar David, Johannesdottir Fjola, Ferguson Stephen J, Helgason Benedikt
Future Health Technologies Programme, Singapore-ETH Centre, CREATE campus, 1 Create Way, CREATE Tower, #06-01, Singapore, 138602, Singapore.
Institute for Biomechanics, ETH Zürich, Zurich, Switzerland.
Osteoporos Int. 2025 May 12. doi: 10.1007/s00198-025-07503-3.
The discriminative accuracy of femoral strength was significantly higher than that of aBMD over 16 years of follow-up for classifying hip fractures and major osteoporotic fractures. The use of accurate thresholds, whether for aBMD or other imaging-based biomarkers, is crucial to improve sensitivity and identify high-risk older adults.
Areal bone mineral density (aBMD) is a surrogate for bone strength but has limited prognostic value. Finite element (FE)-derived femoral strength offers a biomechanical alternative to aBMD for fracture risk assessment, but its long-term predictive value remains unclear. This study compared the discriminatory accuracy of aBMD and femoral strength for hip (HFs) and major osteoporotic fractures (MOFs) over 16 years, accounting for mortality risk.
In the prospective Age Gene/Environment Susceptibility-Reykjavik (AGES-Reykjavik) Study, elderly participants underwent CT scans at entry and automated algorithms were used to compute aBMD and femoral strength. Time-dependent area under the receiver operating characteristic curves (AUC) was used to compare the predictive abilities of aBMD and femoral strength. Optimal cutoffs at the Youden's index were compared with the World Health Organization (WHO)-defined aBMD cutoffs at various time points.
The cohort comprised 4621 older adults (mean age 76 ± 5 years). Femoral strength had a significantly higher AUC than aBMD in identifying HFs (p < 0.05) from the 6th year in males and females, while their AUCs in predicting MOFs were similar. WHO-defined aBMD showed low sensitivity (17-52%) but high specificity (78-94%) for both HFs and MOFs. The sensitivity of optimal femoral strength was significantly higher than that of aBMD at comparable specificity by 5-19% for HFs and 2-10% for MOFs (p < 0.05).
Both image-based markers predict long-term fracture risk and enable opportunistic screening with existing CT scans. However, femoral strength demonstrates better discriminatory accuracy than aBMD. The low sensitivity of the WHO-defined aBMD demonstrates the necessity to revise current risk assessment criteria.
在长达16年的随访中，对于髋部骨折和严重骨质疏松性骨折的分类，股骨强度的鉴别准确性显著高于骨密度（aBMD）。使用准确的阈值，无论是对于骨密度还是其他基于影像的生物标志物，对于提高敏感性和识别高危老年人至关重要。
面积骨密度（aBMD）是骨强度的替代指标，但预后价值有限。基于有限元（FE）的股骨强度为骨折风险评估提供了一种替代骨密度的生物力学方法，但其长期预测价值仍不明确。本研究比较了骨密度和股骨强度在16年中对髋部骨折（HFs）和严重骨质疏松性骨折（MOFs）的鉴别准确性，并考虑了死亡风险。
在前瞻性的年龄基因/环境易感性-雷克雅未克（AGES-雷克雅未克）研究中，老年参与者在入组时接受了CT扫描，并使用自动算法计算骨密度和股骨强度。采用时间依赖性受试者工作特征曲线下面积（AUC）来比较骨密度和股骨强度的预测能力。将约登指数处的最佳截断值与世界卫生组织（WHO）在不同时间点定义的骨密度截断值进行比较。
该队列包括4621名老年人（平均年龄76±5岁）。在男性和女性中，从第6年起，股骨强度在识别髋部骨折方面的AUC显著高于骨密度（p<0.05），而它们在预测严重骨质疏松性骨折方面的AUC相似。WHO定义的骨密度对髋部骨折和严重骨质疏松性骨折的敏感性较低（17-52%），但特异性较高（78-94%）。在可比的特异性下，最佳股骨强度的敏感性比骨密度显著高5-19%（髋部骨折）和2-10%（严重骨质疏松性骨折）（p<0.05）。
两种基于影像的标志物都能预测长期骨折风险，并可利用现有的CT扫描进行机会性筛查。然而，股骨强度的鉴别准确性优于骨密度。WHO定义的骨密度敏感性较低，表明有必要修订当前的风险评估标准。
