输血相关铁蓄积对再生障碍性贫血患者骨密度的影响

Effect of transfusion-associated iron accumulation on bone mineral density in patients of aplastic anemia

目的研究再生障碍性贫血输血相关铁蓄积患者的骨密度,探讨继发性铁蓄积对骨代谢的影响。方法回顾性研究35例再生障碍性贫血合并输血相关铁蓄积的患者资料,分析患者每次输血前血红蛋白、红细胞比容积及相关生化指标以及检测研究结束时的血清铁蛋白、转铁蛋白以及腰椎和股骨颈骨密度。采用t检验、方差分析、卡方检验、Pearson或Spearman相关分析、多元逐步回归分析以及偏相关分析研究患者骨密度与铁代谢指标、血清生化指标的相关性。结果患者平均血清铁蛋白水平为(1292.16±655.14)mg/L,明显高于正常水平;平均腰椎和股骨颈骨密度T值/Z值分别为-2.06和-1.58,低于正常人水平。骨量减少或骨质疏松组患者与骨量正常组相比,具有更高的血清铁蛋白和更低体质量指数和血清白蛋白;相关分析提示腰椎或股骨颈骨密度与年龄及血清铁蛋白呈负相关(相关系数分别为-0.730、0.620及-0.500、-0.410,P<0.05),与体质量指数、血清白蛋白和碱性磷酸酶呈正相关(P<0.05);多元回归分析提示,年龄和血清铁蛋白是影响腰椎和股骨颈骨密度的主要因素,进一步矫正年龄因素发现,腰椎和股骨颈骨密度与血清铁蛋白呈负相关,相关系数分别为-0.58和-0.41(P<0.05)。结论再生障碍性贫血输血相关铁蓄积患者存在骨密度降低,骨密度与体内铁蓄积水平呈负相关。

Objective To explore the effects of secondary iron accumulation on bone metabolism by analyzing bone mineral density(BMD)in patients of aplastic anemia with transfusion-associated iron accumulation.Methods The 35 cases of aplastic anemia were included.Hemoglobin,hematocrit,and related biochemical indexes were measured before blood transfusion at each visit.Serum ferritin,transferrin,lumbar and femoral BMD were measured at the end of the study.The relationship between BMD and iron metabolism were studied with t-test,variance analysis,Chi square test,pearson/spearman linear analysis,multiple regression analysis,and partial correlation analysis.Results The mean serum ferritin level was(1292.16±655.14)mg/L,which was much higher than the normal ranges.The mean T/Z scores for BMD at lumbar spine and femoral neck were-2.06 and-1.58,respectively,which below the normal ranges.Osteopenia/osteoporosis group was strongly associated with older age,lower body mass index,higher serum ferritin,and lower serum albumin.The correlations analysis showed BMD at both lumbar spine and femoral neck was positively correlated with body mass index,serum albumin and alkaline phosphatase(r=-0.730,-0.620 and r=-0.500,-0.410,P<0.05),and negatively correlated with age and serum ferritin(P<0.05).Further multiple regression analysis showed that age and serum ferritin level were the main factors influencing the BMD at lumbar spine and femoral neck.After adjusting age,BMD at lumbar spine and femoral neck showed negative correlation with the serum ferritin level(r=-0.58,-0.41,P<0.05).Conclusion There was low BMD in patients with aplastic anemia of transfusion-associated iron accumulation,and BMD was negatively correlated with iron accumulation.