探讨放射吸收法测量指骨骨密度筛查绝经后妇女骨质疏松症的最佳临界值

目的 研究放射吸收法（radiographic absorptiometry, RA）测量指骨骨密度（bone mineral density, BMD）筛查绝经后妇女骨质疏松症的最佳临界值。 方法 招募650名肝肾功能正常的中国绝经后女性受试者，采用双能X线骨密度仪（dual energy X-ray absorptiometry, DXA）测量腰椎L2~L4、左股骨颈的面积BMD值，RA指骨骨密度仪测量非优势手2、3、4指中节指骨的BMD值，构建ROC曲线，探讨RA指骨骨密度作为人群骨质疏松症筛查工具的最佳临界值。 结果 当RA指骨骨密度T值取DXA骨密度的诊断金标准T≤-2.5时，敏感度为74.2%，特异度为72.9%；当RA指骨骨密度T值取≤-2.21为判断骨质疏松症的阈值时，其敏感度较高为81.4%，特异度为62.0%。 结论 T≤-2.21可作为RA指骨骨密度筛查中国绝经后妇女骨质疏松症的最佳临界值。

Optimal Cut-off Value of Phalangeal Radiographic Absorptiometry to Identify Osteoporosis in Postmenopausal Women

Objective To study the optimal cut-off value of phalangeal radiographic absorptiometry (RA) to identify osteoporosis in postmenopausal women. Methods A total of 650 postmenopausal women were recruited in this study. Bone mineral density (BMD) at lumbar spine and left proximal femur neck was measured by dual-energy X-ray absorptiometry (DXA) as the standard method to identify postmenopausal osteoprosis. Phalangeal bone density was estimated by the use of RA. Optimal cut-off value of phalangeal RA was determined using a ROC curve for screening the ostreoporosis cases. Results When the cut-off value of phalangeal RA was T score ≤-2.5, the sensitivity was 74.2%, the specificity was 72.9%. When the cut-off value was T score ≤-2.21, the sensitivity was 81.4%, the specificity was 62.0%. Conclusion The cut-off value of phalangeal RA as T score ≤-2.21. which has higher sensitivity could be optimal to identify postmenopausal osteoporosis.