van Wassenaer A G, Kok J H, de Vijlder J J, Briët J M, Smit B J, Tamminga P, van Baar A, Dekker F W, Vulsma T
Department of Neonatology, Academic Medical Center, University of Amsterdam, the Netherlands.
N Engl J Med. 1997 Jan 2;336(1):21-6. doi: 10.1056/NEJM199701023360104.
Premature infants who have transient hypothyroxinemia in the first weeks of life may have developmental delay and neurologic dysfunction. Whether thyroxine treatment during this period results in improved developmental outcomes is not known.
We carried out a randomized, placebo-controlled, double-blind trial of thyroxine supplementation in 200 infants born at less than 30 weeks' gestation. Thyroxine (8 microg per kilogram of birth weight) or placebo was administered daily, starting 12 to 24 hours after birth, for six weeks. Plasma free thyroxine concentrations were measured weekly for the first eight weeks after birth. Scores on the Bayley Mental and Psychomotor Development Indexes and neurologic function were assessed at 6, 12, and 24 months of age (corrected for prematurity).
Mortality and morbidity up to the time of discharge from the hospital were similar in the study groups. At 24 months of age, 157 infants were evaluated. Overall, neither mental nor psychomotor scores differed significantly between the study groups at any time, nor was the frequency of abnormal neurologic outcome significantly different. In thyroxine-treated infants born at gestational ages of less than 27 weeks, the score on the Bayley Mental Development Index at 24 months of age was 18 points higher than the score for the infants with similar gestational ages at birth in the placebo group (P=0.01); for thyroxine-treated infants born at 27 weeks or later, the mental-development score was 10 points lower than that of their counterparts in the placebo group (P=0.03). There was no relation between the initial plasma free thyroxine concentration and the effect of treatment.
In infants born before 30 weeks' gestation, thyroxine supplementation does not improve the developmental outcome at 24 months.
出生后最初几周出现短暂性甲状腺素血症的早产儿可能会出现发育迟缓及神经功能障碍。在此期间进行甲状腺素治疗是否能改善发育结局尚不清楚。
我们对200例孕周小于30周的早产儿进行了一项随机、安慰剂对照、双盲的甲状腺素补充试验。出生后12至24小时开始，每日给予甲状腺素（8微克/千克出生体重）或安慰剂，持续六周。出生后的前八周每周测量血浆游离甲状腺素浓度。在6、12和24个月龄（校正早产因素）时评估贝利智力和精神运动发育指数得分及神经功能。
研究组直至出院时的死亡率和发病率相似。在24个月龄时，对157例婴儿进行了评估。总体而言，研究组在任何时候的智力和精神运动得分均无显著差异，神经功能异常结局的频率也无显著差异。在孕周小于27周的接受甲状腺素治疗的婴儿中，24个月龄时贝利智力发育指数得分比安慰剂组中出生时孕周相似的婴儿高18分（P = 0.01）；对于孕周为27周或更大孕周出生的接受甲状腺素治疗的婴儿，智力发育得分比安慰剂组中的对应婴儿低10分（P = 0.03）。初始血浆游离甲状腺素浓度与治疗效果之间无关联。
对于孕周小于30周的婴儿，补充甲状腺素并不能改善24个月时的发育结局。
