ESPE Abstracts

Introduction: The main purpose of the study was to determine whether anthropometric measurements at preschool (PS)-age, in which physiological adiposity rebound is detected, and LT4 dose have an effect on the age of onset of puberty in children with hypothyroidism.

Methods: This is an observational and retrospective study.

Results: Puberty had begun in 44 girls and 25 boys out of 115 children included in the study. Mean follow-up period of the patients was 112.2± 29 months. Two girls and one boy had central precocious puberty. Puberty began at a mean age of 9.77±1.2 years for girls and 11.31±0.6 years for boys. Girls had menarche at a mean age of 12.06±1.0 years. PS-age was mean 6.22 ± 0.2 years (6-6.8 years). At the PS-age, height, height-SD and LT4 doses was statistically different in patients with thyroid agenesis and thyroid hypoplasia. Height-SD at PS-age was positively correlated with the height-SD at the puberty onset in girls and in boys and height-SD at menarche. BMI-SD at PS-age was positively correlated with BMI-SD at the puberty onset in girls and in boys and BMI-SD at menarche. At PS-age LT4 dose was negatively correlated with height-SD and BMI-SD at PS-age, but negatively correlated with puberty onset BMI-SD in girls, and puberty onset height-SD in boys.

Conclusion: In this study, it was found that PS-aged patients with thyroid agenesis were shorter than those with thyroid hypoplasia. It was determined that those who received high-dose LT4 at PS age were short and lean. It was showed that PS-aged height and BMI could be a determinant in predicting height and BMI at the onset of puberty. While the age of onset of puberty in our female patients with CH was similar to their healthy peers and patients with hypothyroidism in recent studies, the age of onset of puberty for boys was younger than both their healthy peers and children with hypothyroidism of previous studies.