骨源性碱性磷酸酶预测骨质疏松骨折患者再骨折的意义

The predictive significance of bone alkaline phosphatase on the second fracture in patients with osteoporotic fractures

目的探讨骨质疏松患者初次骨折后发生再骨折的影响因素,分析血清骨源性碱性磷酸酶(BALP)对预测再发骨折的临床价值。方法前瞻性队列研究纳入我院178例确诊的50岁以上骨质疏松性骨折患者。初次骨折时检测患者血清BALP水平、骨密度值(BMD)、钙、磷及临床一般资料等,跟踪随访4年,以患者再发骨折为随访终点事件。采用Kaplan-Meier分析和多元Cox回归模型进行再发骨折的风险因素研究,受试者工作特征(ROC)曲线用于评判BALP的预测价值。结果 178例骨质疏松性骨折患者4年内30(16.9%)例发生再次骨折。Cox回归分析结果显示BALP、年龄、性别和BMD是患者再发骨折的独立影响因素。以BALP为预测标准,ROC曲线下面积为0.757,诊断临界点为29.0μg/L,灵敏度及特异度分别为84.3%、63.8%。Kaplan-Meier分析显示BALP>29.0μg/L患者骨折再发率较BALP≤29.0μg/L更高(p=0.026)。结论骨质疏松骨折患者发生再骨折的风险较高,检测血清BALP水平是有效可行的预测指标。

Objective To explore the risk factors of re-fracture in patients with osteoporotic fractures, and to evaluate the value of serum bone alkaline phosphatase （ BALP） as a prognostic indicator in patients with re-fractures.Methods A prospective cohort study including 178 patients, who were over 50 years old and diagnosed with osteoporotic fractures and in our hospital, was performed.The serum levels of BALP, calcium, and phosphorus were determined at the time with initial fracture.The bone mineral density （ BMD） was detected.And other clinical general data were also collected and analyzed.All the patients were followed up for 4 years.The occurrence of re-fracture or death was defined as end-point event.Kaplan-Meier analysis and multivariate Cox regression model were used for the analysis of risk factors.Receiver operating characteristic curve （ ROC curve ） was used to evaluate the predictive value of BALP.Results Among all these 178 patients, 30 （ 16.9%） had re-fractures in 4 years.Cox regression analysis showed that BALP level, age, gender, and BMD were independent and important factors for re-fracture.Using BALP as a forecast standard, the ROC area under the curve （ AUC） was 0.757, and diagnose critical point was 29.0 μg/L.The sensitivity and specificity were 84.3%and 63.8%, respectively.Kaplan-Meier analysis revealed that patients with serum BALP 〉29.0 μg/L had a higher re-fracture incidence than patients with serum BALP ≤ 29.0 μg/L （ P=0.026 ） .Conclusion The prevalence of second fracture is high in patients with osteoporotic fractures.The serum BALP level is an effective and suitable predictor.