ESPE Abstracts

Background: Subclinical congenital hypothyroidism is a condition that occurs when serum thyroid stimulating hormone (TSH) is elevated, with circulating thyroid hormone levels within their reference ranges, observed at neonatal screening. To date, the question of the need for treatment of this condition remains open. Also the effect on the physical and neuropsychiatric development of children remains unclear.

Aims: To evaluate the impact of various therapeutic approaches on the neuropsychiatric and physical development of children with subclinical congenital hypothyroidism.

Methods: A statistical analysis of thyroid profile, physical and neuropsychiatric development indicators was carried out between two groups of patients with congenital subclinical hypothyroidism, depending on the therapy received.

Results: This study included 24 children. The first group comprised 15 children who were observed for 1–15 years (Me 3.5 years [3.0; 6.8]) without treatment. The second group included 9 children who were treated for 1–10 years (Me 4.0 years [3.8; 7.7]) until complete discontinuation for the purpose of revising the diagnosis of CH. A statistically significant decrease in TSH levels was obtained after drug withdrawal compared with the baseline level in the group of patients receiving hormone replacement therapy. Median baseline TSH levels were 50.1 mIU/L [35.6, 75.1], endpoint 16.1 mIU/L [6.3, 21.0]. Also, the initial normal level of free thyroxine was maintained in this group. Manifest hypothyroidism was not diagnosed in any of the patients included in the study. There were no statistically significant differences between the two groups in height, target height, BMI and neuropsychiatric development.

Conclusions: The first evidence was obtained of the absence of the effect of "elevated" TSH levels on the neuropsychological and physical development of children with congenital subclinical hypothyroidism during dynamic observation (at least the first 4 years of life).