胎龄和日龄对早产儿甲状腺功能指标的影响

目的 分析胎龄和日龄对早产儿甲状腺功能的影响,为进一步研究基于胎龄和日龄制定适用于早产儿的甲状腺功能参考区间。方法 收集2017年5月—2020年5月在深圳市龙岗中心医院新生儿科住院早产儿的甲状腺功能指标[促甲状腺激素(TSH)、甲状腺素(T₄)、游离甲状腺素(FT₄)和三碘甲状腺原氨酸(T₃)]结果。按照胎龄和生后日龄分组,对比各组早产儿甲状腺功能指标水平,并分析各检测指标随胎龄和生后日龄的变化。结果 共纳入符合条件的早产儿497例,其中早期早产儿组206例、中期早产儿组128例和晚期早产儿组163例。1)早期早产儿组甲状腺功能指标分别与中期、晚期早产儿组比较,差异有统计学意义(P＜0.05);中期早产儿组甲状腺功能指标与晚期早产儿组比较,差异无统计学意义(P＞0.05)。2)各胎龄组早期早产儿T₄、FT₄和T₃水平比较,差异有统计学意义(H=36.588、32.381、43.021,P＜0.01),TSH水平差异无统计学意义(P＞0.05)。3)生后日龄7~14 d组与14~28 d组早产儿T₄、FT₄和T₃水平比较,差异有统计学意义(Z＝8.706、6.904、9.497,P＜0.05),而血清TSH比较,差异无统计学意义(P＞0.05)。4)早产儿T₄、FT₄、T₃水平与胎龄、日龄呈正相关性,而TSH 水平与胎龄、日龄之间均无相关性。结论 早期早产儿T₄、FT₄、T₃水平与胎龄、日龄呈正相关,需基于胎龄和日龄制定适用于早产儿的甲状腺功能参考区间。

Influence of gestational age and postnatal age on thyroid function of preterm infants

Objective To analyze the influence of gestational age and postnatal age on thyroid function indexes in premature infants, in order to establish a reference interval for thyroid function for premature infants based on gestational age and postnatal age. Methods The levels of thyroid stimulating hormone (TSH), thyroxine (T4), free thyroxine (FT4) and triiodothyronine (T3) of premature infants in neonatal department of Longgang Central Hospital from May 2017 to May 2020 were collected. Infants were divided into early preterm infants, mid-term premature infants and late premature infants according to gestational age and postnatal age. The levels of thyroid function index in each group were compared, and the changes of each index with gestational age and postnatal age were analyzed. Results A total of 497 premature infants were included. The early, mid-term and late premature infants were 206, 128, and 163 cases, respectively. 1) The levels of thyroid function indexes of early premature infants were significantly different from those of mid-late and late preterm infants(P＜0.05), but the difference was not significant between mid-late and late preterm infants(P＞0.05). 2) The T₄, FT₄ and T₃ levels of early preterm infants were significantly different among infants with different gestational ages(H=36.588, 32.381, 43.021, P<0.05), while the significant difference was not found in TSH level(P＞0.05). 3)The T₄, FT₄ and T₃ levels of premature infants were significantly different between 7—14 days group and 14—28 days group (Z=8.706, 6.904, 9.497,P＜0.05), but the significant difference was not found in TSH level(P＞0.05). 4) The T₄, FT₄, T₃ level of premature infants was positively correlated with gestational age and postnatal age, but the correlation was not significant between TSH level and gestational age and postnatal age. Conclusion The levels of T₄, FT₄ and T₃ in early preterm infants are positively correlated with gestational age and postnatal age, so the reference interval of thyroid function for preterm infants should be established based on gestational age and postnatal age.