Thyroid Hormone Status in Preterm Infants A Comparative Analysis between Small for Gestational Age and Appropriate for Gestational Age Infants at a Tertiary Care Hospital
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https://doi.org/10.61705/x5mnr697Keywords:
premature babies, Thyroid hormone, tertiary care hospital, small for gestational age, appropriate for gestational ageAbstract
Objective: The aim of this study is to compare the thyroid hormone profiles of small for gestational age (SGA) and appropriate for gestational age (AGA) infants at a tertiary care hospital, and to examine the thyroid hormone profiles of preterm infants.
Methods: The study involved the enrollment of 200 preterm newborns in total, comprising 100 SGA and 100 AGA children. Measurements were made and thyroid hormone levels (TSH, fT4, and T3) were compared between the two groups. We conducted subgroup analyses according to birth weight and gestational age. The association between thyroid hormone levels and gestational age and birth weight was investigated using correlation analysis.
Results: Compared to AGA children, SGA infants had higher levels of TSH (mean 8.0 mU/L vs. 4.5 mU/L, p<0.001) and lower levels of fT4 (mean 12.5 pmol/L vs. 18.0 pmol/L, p<0.001) and T3 (mean 1.2 nmol/L vs. 1.8 nmol/L, p<0.001). Significant differences in thyroid hormone levels were seen in subgroup analyses according to birth weight and gestational age. As gestational age and birth weight grew, TSH levels declined and fT4 and T3 levels climbed. The results of correlation analyses indicated a significant positive correlation between fT4 (r = 0.40, p < 0.001) and T3 (r = 0.35, p < 0.001) levels and both gestational age and birth weight, and a significant negative correlation between TSH levels and both (r = -0.45, p < 0.001) and birth weight (r = -0.50, p < 0.001).
Conclusion: The study concludes that there are notable variations in thyroid hormone levels between preterm children classified as SGA and AGA. Specifically, SGA newborns exhibit reduced levels of fT4 and T3, whereas TSH levels are higher. Thyroid hormone levels were shown to be influenced by gestational age and birth weight, with higher levels of fT4 and T3 and lower levels of TSH being linked to higher gestational age and birth weight. In order to maximize growth and neurodevelopmental outcomes, these data highlight the significance of routinely monitoring thyroid hormone levels in preterm newborns, especially in SGA infants.
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