地中海贫血患儿维生素D水平及影响因素分析

Analysis of status and possible risk factors of vitamin D deficiency in children with thalassemia

目的了解我国地中海贫血儿童维生素D(vitamin D,Vit D)水平状况。方法 81例各型地中海贫血患儿纳入研究,收集临床资料,计算体质指数Z分值(body mass index Z-score,BMI-Z分值);测定血清25-(OH)D、钙和磷水平;采用PCR-RFLP方法分析Vit D受体(vitamin D receptor,VDR)基因Fok I、Bsm I、Apa I位点多态性。结果地中海贫血患儿25-(OH)D水平为(23.7±9.2)ng/mL,显著低于对照组的(28.3±10.5)ng/mL(P<0.05);地中海贫血合并Vit D缺乏或不足的发生率为66.7%,比对照组高;重型地中海贫血Vit D缺乏或不足者检出率88.9%,中间型64.0%,轻型48.3%。所有患儿血清钙、磷浓度均正常。BMI-Z分值≤-1与Vit D缺乏或不足相关,而VDR基因多态性、性别及居住地并非危险因素。结论地中海贫血患儿Vit D缺乏或不足发生率高,且与贫血严重程度以及营养状态相关。

Objective To investigate the status of vitamin D in children with thalassemia. Methods A total of 81 children,including thalassemia major（TM）,intermedia（TI）and trait（TT）patients,were enrolled in this study.Clinical data were recorded and body masses index（BMI）Z score was calculated.Serum 25-hydroxyvitamin D [25-（OH）D],calcium and phosphorus were detected by routine methods,and vitamin D receptor（VDR）gene polymorphisms（Fok I,Bsm I,Apa I）were analyzed by PCR-RELP. Results 25-（OH）D level in thalassemia patient group was lower than that in control child group[（23.7±9.2）ng/mL vs.（28.3±10.5）ng/mL,P〈0.05].66.7% patients with thalassemia were found to be vitamin D deficient or insufficient.The percentage of vitamin D deficiency or insufficiency cases in TM,TI and TT was88.9%,64.0% and 48.3%,respectively.The levels of serum calcium and phosphorus of all patients were normal.BMI-Z score≤-1 was the risk factor of vitamin D deficiency or insufficiency in thalassemia children,but VDR gene polymorphisms,gender,and inhabited area were not. Conclusions High prevalence of vitamin D deficiency or insufficiency in thalassemia children in China is showed.Severe anemia and low BMI are the risk factors.