Abstract: Objective　To investigate the clinical significance of thyroid function changes in premature infants in disease state. Methods　This was a retrospective stady Ninety premature infants treated at Neonatal Intensive Care Unit, Zhengzhou First People's Hospital from January 2019 to December 2020 were selected; among which, the 48 ones in disease state were set as an observation group, and the rest 42 ones who had no complications a control group. The observation group were divided into a critical group and a not-critical group according to the disease severity. There were 48 boys and 42 girls, with an gestational age of (31.17±1.44) weeks and a birth weight of (1 449±255) g. The serum levels of free triiodothyronine (FT3), free thyroxine (FT4), and thyrotropin (TSH) were detected on day 7 and 14 after their birth. The thyroid function was compared between the groups. The statistical software SPSS 21.0 was used to analyzed the data. The measurement data of normal distribution were expressed as (x±s), and compared between the groups by independent-sample t test. Results　The levels of FT3 at the first and second inspection in the observation group were lower than those in the control group [(3.36±0.68) pmol/L vs. (3.80±0.75) pmol/L and (3.49±0.75) pmol/L vs. (3.94±0.60) pmol/L], with statistical differences (both P<0.05). There were no statistical differences in the levels of FT4 and TSH at the first and second inspection and the FT4 level at the first inspection in the critical group were lower than those in the not-critical group [(3.15±0.64) pmol/L vs. (3.60±0.65) pmol/L, (3.30±0.80) pmol/L vs. (3.73±0.63) pmol/L, and (15.08±3.19) pmol/L vs. (17.21±3.78) pmol/L], with statistical differences (all P<0.05). The levels of FT4 and TSH at the second inspection were (17.57±3.15) pmol/L and (6.24±2.02) mU/L in the critical group, and were (19.10±2.27) pmol/L and (6.58±2.10) mU/L in the not-critical group, with no statistical differences between these two groups (all P>0.05) and with statistical differences between the first and second inspection in the same group (all P<0.05). Conclusions　FT3 decreases in premature infants in disease state, and FT3 and FT4 reduce in the critical ones. Thyroid hormone decrease and disease severity of premature infants interact with each other.

Key words: Thyroid function, Premature infants, Disease state

摘要： 目的　探讨早产儿疾病状态时甲状腺功能变化的临床意义。方法　本文为回顾性研究。选择2019年1月至2020年12月郑州市第一人民医院新生儿重症监护病房（NICU）收治的早产儿90例，其中合并疾病状态的早产儿48例为观察组，无合并症早产儿42例为对照组，观察组根据疾病严重程度分为危重组26例和非危重组22例。其中男48例、女42例，胎龄（31.17±1.44）周，出生体质量（1 449±255）g。于早产儿出生后第7天（第1次）和第14天（第2次）分别检测各组早产儿血清游离原氨酸（FT3）、游离甲状腺素（FT4）和促甲状腺素（TSH）。比较各组早产儿的甲状腺功能。应用SPSS 21.0统计软件进行数据分析，符合正态分布的计量资料以均数±标准差（x±s）表示，组间比较采用独立样本t检验。结果　观察组早产儿第1次检查FT3为（3.36±0.68）pmol/L，第2次检查为（3.49±0.75）pmol/L，均低于对照组的（3.80±0.75）pmol/L、（3.94±0.60）pmol/L，差异均有统计学意义（均P<0.05）；观察组早产儿的FT4、TSH第1次、第2次检查与对照组比较差异均无统计学意义（均P>0.05）。危重组第1次FT3为（3.15±0.64）pmol/L，第2次为（3.30±0.80）pmol/L，非危重组分别为（3.60±0.65）pmol/L、（3.73±0.63）pmol/L，两组比较差异均有统计学意义（均P<0.05）；危重组早产儿第1次FT4为（15.08±3.19）pmol/L，低于非危重组的（17.21±3.78）pmol/L，差异有统计学意义（P<0.05）；危重组与非危重组第2次FT4分别为（17.57±3.15）pmol/L和（19.10±2.27）pmol/L，TSH分别为（6.24±2.02）mU/L和（6.58±2.10）mU/L，虽然组间比较差异均无统计学意义（均P>0.05），但与同组第1次比较差异均有统计学意义（均P<0.05）。结论　疾病状态时早产儿FT3减低，严重病例可同时出现FT4下降。甲状腺激素降低与早产儿疾病严重程度存在相互影响的关系。

关键词: 甲状腺功能, 早产儿, 疾病状态