Wang Yu, Hao Yan-jie, Deng Xue-rong, Li Guang-tao, Geng Yan, Zhao Juan, Zhou Wei, Zhang Zhuo-li
Department of Rheumatology and Clinical Immunology, Peking University First Hospital, Beijing 100034, China.
Beijing Da Xue Xue Bao Yi Xue Ban. 2015 Oct 18;47(5):781-6.
To verify the fracture risk assessment tool (FRAX) to estimate the probability of osteoporotic fracture in patients with rheumatoid arthritis (RA) with or without bone mineral density (BMD), and identify associated risk factors of osteoporosis.
In the study, 200 patients with rheumatoid arthritis aged more than 40 years in Peking University First Hospital from Dec. 2009 to Dec. 2012 were recruited. Clinical information was obtained from a questionnaire of their case history and medical records. FRAX tool was administered. Their lumber spine and left femoral BMD were determined by dual energy X ray absorptiometry. The gender, age, disease duration, menopause status, body mass index (BMI) and accumulative dose of glucocorticoid were obtained in retrospect. Correlation analysis was conducted between the BMD and clinical information.
The study population (female, 77.5%) had a mean age of 59.4 years, in which 10 (13%) patients showed a normal BMD, 67 (87%) were osteopenia or osteoporosis, while 32 patients (16%) had fragile fracture. Compared with the patients with normal BMD, the subjects with low BMD had significantly older age, longer period for corticoids usage, higher day dose and accumulated dose of corticoids.The 10-year fracture risk of sustaining major osteoporotic fractures and hip fracture was higher. No significant difference was observed between the 10-year fracture risks calculated with BMD and without BMD. The values of the different area under the receiver operating characteristic (ROC) curve (AUC) for major and hip fractures calculated in three ways: without BMD, with the femoral neck BMD, and with T-score. The best result was for FRAX tool for hip fracture with the T-score (AUC 0.899). A stepwise multivariate linear regression model was constructed to explore the relationship between the different clinical factors studied and a low BMD. Three statistically significant variables for lumber BMD were pain on visual assessment scale (VAS) (P=0.02), fracture history (P=0.003) and a higher steroid accumulated dose (P=0.008). Three statistically significant variables for left hip BMD were age (P<0.001), fracture history (P=0.05) and lower BMI (P=0.03).
Low BMD is a common complication in RA patients. Risk factors for major fracture and hip fracture are increased. There is a positive correlation between FRAX calculated with and without BMD or T score. FRAX with the femoral neck T score or BMD presents a discriminatory capacity better than FRAX without BMD, according to the AUC ROC.
验证骨折风险评估工具（FRAX）用于估算伴或不伴骨密度（BMD）的类风湿关节炎（RA）患者骨质疏松性骨折概率，并确定骨质疏松的相关危险因素。
本研究纳入了2009年12月至2012年12月北京大学第一医院200例年龄大于40岁的类风湿关节炎患者。通过病史问卷和病历获取临床信息。应用FRAX工具。采用双能X线吸收法测定其腰椎和左股骨骨密度。回顾性获取患者的性别、年龄、病程、绝经状态、体重指数（BMI）及糖皮质激素累积剂量。对骨密度与临床信息进行相关性分析。
研究人群中女性占77.5%，平均年龄59.4岁，其中10例（13%）患者骨密度正常，67例（87%）为骨量减少或骨质疏松，32例（16%）发生脆性骨折。与骨密度正常的患者相比，骨密度低的患者年龄显著更大，使用皮质类固醇的时间更长，皮质类固醇的日剂量和累积剂量更高，发生主要骨质疏松性骨折和髋部骨折的10年骨折风险更高。使用骨密度和不使用骨密度计算的10年骨折风险之间未观察到显著差异。通过三种方式计算主要骨折和髋部骨折的受试者工作特征（ROC）曲线下不同面积（AUC）值：不使用骨密度、使用股骨颈骨密度和使用T值。对于髋部骨折，使用T值的FRAX工具结果最佳（AUC 0.899）。构建逐步多元线性回归模型以探讨所研究的不同临床因素与低骨密度之间的关系。腰椎骨密度的三个具有统计学意义的变量为视觉模拟评分法（VAS）疼痛评分（P = 0.02）、骨折史（P = 0.003）和较高的类固醇累积剂量（P = 0.008）。左髋骨密度的三个具有统计学意义的变量为年龄（P < 0.001）、骨折史（P = 0.05）和较低的BMI（P = 0.03）。
低骨密度是类风湿关节炎患者的常见并发症。主要骨折和髋部骨折的危险因素增加。使用和不使用骨密度或T值计算的FRAX之间存在正相关。根据ROC曲线下面积，使用股骨颈T值或骨密度的FRAX比不使用骨密度的FRAX具有更好的鉴别能力。
