胸、腰椎骨质疏松性骨折患者椎体骨铁含量、血清铁蛋白与骨密度的相关性

Correlation among bone iron content,serum ferritin and bone mineral density in patients with thoracolumbar fractures

目的探讨胸、腰椎骨质疏松性骨折患者椎体骨铁含量、血清铁蛋白与骨密度的相关性。方法回顾性分析2008年1月至2014年12月243例在苏州市第七人民医院因胸腰椎椎体骨折并接受手术治疗的患者的临床资料,其中男91例,女152例;年龄50~81岁,平均年龄62.5岁。患者入院后第2天留空腹血清标本测定血清铁蛋白和骨代谢指标并测量椎体骨密度;根据椎体骨密度检测值分为骨量减少组(-2.5<T值<-1.0)和骨质疏松组(T值≤-2.5),并于术中取适量椎体松质骨行骨铁含量检测和骨铁染色。结果骨量减少组与骨质疏松组患者在性别、年龄、身高、体质量等临床资料比较差异无统计学意义(P>0.05),资料具有可比性。各变量与骨密度Pearson相关分析结果显示年龄、骨铁、血清铁蛋白、Ⅰ型原胶原氨基端延长肽、Ⅰ型胶原C端肽β降解产物与股骨颈骨密度相关系数r值分别为-0.712、-0.348、-0.323、-0.236、-0.227,与L_(1-4)骨密度相关系数r值分别-0.541、-0.206、-0.213、-0.184、-0.191,均呈负相关(P<0.05);体质量、体质量指数、转铁蛋白、总铁结合力与股骨颈骨密度相关系数r值分别为0.257、0.237、0.185、0.163,与L_(1-4)骨密度相关系数r值分别为0.361、0.335、0.204、0.197,均呈正相关(P<0.05)。骨铁、血清铁蛋白可进入股骨颈及腰椎L_(1-4)骨密度回归模型,股骨颈R^2=0.388,L_(1-4)R^2=0.374;骨铁和血清铁蛋白与腰椎骨密度呈负相关。结论胸腰椎骨质疏松性椎体骨折患者,椎体骨铁含量及血清铁蛋白含量越高,骨密度越低;骨铁及血清铁蛋白含量可能是胸腰椎骨质疏松性椎体骨折发生的危险因素之一。

Objective To explore the association among bone iron content, serum ferritin （SF） and bone mineral density in patients with thoracolumbar fractures. Methods A retrospective analysis was conducted in 243 patients with thoracotumbar fracture who were undergone pereutaneous kyphoplasty from January 2008 to December 2014. Mean age of the patients （91 males and 152 females） was 62. 5 years （range： 50 -81 years）. The patients were assigned to osteopenia group and osteoporosis group based on the preoperative bone mineral density （BMD）. Blood samples were collected to determine iron metabolism and bone turnover biomarkers after overnight fasting. Bone specimens were obtained for detecting bone iron contents and performing iron stain respectively after percutaneous kyphoplasty. Results There was no significant statistical significance between osteopenia group and osteoporosis group in gender, age, height, and weight （P 〉0.05）. Pearson correlation analysis showed that the age, bone iron content, SF, serum procollagen type 1 N-terminal propeptide, and β-earboxy terminal telopeptide of collagen type 1 were negatively correlated with BMD at femoral neck （r= -0.712, -0.348, -0.323, -0.236, -0.227; all P 〈0.05） and lumbar spine （r = -0.541, -0.206, -0.213, -0.184, -0.191; all P〈0.05）; the weight, body mass index, transferrin, and total iron binding capacity were positively correlated with BMD at femoral neck and lumbar spine （ P 〈 0.05 ）. Bone iron content combined with SF could be put into the regression models of BMD at femoral neck and lumbar spine （ femoral neck R2 = 0. 388, L1-4 R2 = 0. 374）. Both bone iron content and SF were negatively correlated with BMD at lumbar spine （ P 〈 0. 05 ）. Conclusion The higher the values of bone iron and serum iron protein content in osteoporotic vertebral fracture patients, the higher the degree in osteoporosisis. Iron accumulation and osteoporosis is significantly correlated.