早产儿维生素A营养不良及其补充治疗的临床研究

目的　评价早产儿基础维生素A营养状况、与疾病的关系及常规补充的效果。方法　高效液相色谱法检测2006年1月至2007年2月北京大学第一医院出生24 h内的早产儿（147名）血浆视黄醇浓度，足月儿（40名）脐血作为对照。根据临床治疗常规，早产儿静脉（1650 U/d）和（或）口服（750 U/d）补充维生素A，随访早产儿血浆视黄醇浓度。结果　出生时，早产儿血浆视黄醇浓度低于足月儿，差异有统计学意义，分别为（0.161±0.051）μg/mL 和 （0.187±0.055） μg/mL（P = 0.005）。早产儿维生素A 缺乏（VAD）发生率高于足月儿，但差异无统计学意义。多元线性回归分析显示出生体重与血浆视黄醇浓度呈正相关。31例早产儿补充维生素A 2周后，随访血浆视黄醇浓度显著升高，分别为（0.168±0.046） μg/mL和 （0.203±0.063）μg/mL（P = 0.014）；VAD发生率显著下降，分别为100%和48%（P < 0.001）。未发现补充剂量、方式对随访维生素A浓度的影响，未发现出生时血浆视黄醇浓度与新生儿期疾病的关系。结论　早产儿基础维生素A营养状况不良，常规补充可在一定程度上改善2周时维生素A营养状况。

Clinical study on vitamin A status and significance of supplement in premature infants.

Objective　To investigate vitamin A basic nutritional status， influencing factors and the efficacy of routine vitamin A supplement in premature infants. Methods　Premature infants within 24 h of age were selected randomly to examine plasma retinol concentration. Full term infants worked as control. Premature infants received Vitamin A parenteral （1650 U/d） and/or enteral （750 U/d）， and some of them were followed up about every 2 weeks. Plasma retinol level was detected by high-performance liquid chromatography （HPLC）. Results　One hundred and forty-seven premature infants and 40 full term infants were enrolled. Basic serum retinol levels in premature infant were lower than that in full term infants， （0.161±0.051）μg/mL and （0.187±0.055）μg/mL， t = 2.812， P = 0.005. Retinol level had positive relation with birth weight， β = 0.177， P = 0.015. The incidence of VAD （retinol level < 0.200 μg/mL） at birth was higher in premature infants， 78% vs 65%， χ2 = 2.623， P = 0.105. Thirty-one premature infants were followed up about 2 weeks later with enteral and/or parenteral nutrition. Significant increase of plasma retinol level and reduction of VAD incidence were noted， （0.168±0.046） μg/mL vs. （0.203±0.063）μg/mL， t = 2.611， P = 0.014； 100% vs. 48%， χ2 = 18.954， P < 0.001. No relation was showed between basic retinol levels， amount and method of vitamin A supplement with the follow-up levels. Basic retinol levels had no influence on clinical outcomes， such as infection， chronic lung disease and retinopathy of prematurity. Conclusion　Premature infants have a poor vitamin A nutritional status and high incidence of VAD. Current routine vitamin A supplement has benefits to the improvement of its nutritional status in a short period.