不同剂量维生素D对早产儿骨代谢及生长发育影响的队列研究

Effects of Different Vitamin D Doses on Bone Metabolism and Growth and Development Indicators of Preterm infants:A Cohort Study

目的分析不同剂量维生素D(vitamin D,VitD)补充对早产儿骨代谢指标和生长发育指标的影响,为指导早产儿VitD的合理应用提供理论依据。方法选取胎龄<34周或出生体重<1500 g的早产儿为研究对象,采用回顾性队列研究的方法,根据VitD摄入量分为高剂量组(VitD总摄入量≥900 IU/d)和低剂量组(VitD总摄入量<900 IU/d),比较不同剂量VitD摄入对日龄28 d或出院时早产儿骨代谢指标(血清25羟维生素D、碱性磷酸酶、钙和磷水平)和生长发育指标(体重、身长和头围生长速率)的影响。结果符合纳入标准的早产儿共229例,其中高剂量组135例,低剂量组94例。在日龄28 d或出院时,2组早产儿血清25羟维生素D、血清钙水平比较,差异无统计学意义(P>0.05),高剂量组早产儿低磷血症的发生率(χ^(2)=6.215,P=0.045)及血清碱性磷酸酶水平(Z=3.174,P=0.002)低于低剂量组;2组早产儿体重、身长增长速率比较,差异无统计学意义(P>0.05),高剂量组早产儿头围增长速率≥5 mm/周的比例更高(χ^(2)=4.036,P<0.001),头围增长速率更快(β=1.510,95%CI 0.751~2.269,P<0.001)。结论高剂量VitD摄入可改善早产儿骨代谢状态,促进头围增长。

Objective To analyze the effects of various dosages of vitamin D(VitD)supplementation on bone metabolism and growth and development indicators of preterm infants.Methods Preterm infants with gestational age<34 weeks or birth weight<1500 g were divided into high-dose group(Total vitamin D intake≥900 IU)and low-dose group(Total vitamin D intake<900 IU)based on the VitD intake.Multiple linear regression approach for the analysis of the relationships between VitD intake and growth and development indicators(including the growth rate of weight,length,and head circumference)and bone metabolism indicators(including serum 25-hydroxyvitamin D,Alkaline phosphatase,calcium,and phosphorus levels)of preterm infants at 28 days after birth or discharge.Results A total of 229 preterm infants met inclusion criteria,including 135 cases in the highdose group and 94 cases in the low-dose group.There were no significant differences in serum 25-hydroxyvitamin D and calcium levels among the groups(P>0.05).Preterm infants in high-dose group had a lower incidence of hypophosphatemia(χ^(2)=6.215,P=0.045)and a higher level of serum alkaline phosphatase(Z=3.174,P=0.002)compared to the low-dose group.There were no significant differences in the growth rate of weight and length among the groups(P>0.05).Preterm infants with high-dose group had a higher percentage of the growth rate of head circumference≥5 mm per week(χ^(2)=4.036,P<0.001)and a higher growth rate of head circumference(β=1.510,95%CI:0.751~2.269,P<0.001)compared to the low-dose group.Conclusion High-dose vitamin D intake can stabilize bone metabolism and promote the growth rate of head circumference in preterm infants.