Seminara S, Stagi S, Candura L, Scrivano M, Lenzi L, Nanni L, Pagliai F, Chiarelli F
Department of Paediatrics, University of Florence, Anna Meyer Children's Hospital, Via Luca Giordano 13, Florence, Italy.
Horm Metab Res. 2005 Dec;37(12):751-6. doi: 10.1055/s-2005-921104.
Growth hormone (GH) treatment in patients with GH deficiency (GHD) can determine changes in the thyroid function. The clinical significance of these changes remains controversial, and all studies have so far covered rather a short period--usually no longer than one year.
To determine the effect of long-term recombinant hGH treatment in children with idiopathic GHD on the thyroid function.
Nineteen prepubertal children (12 boys and 7 girls, mean age 9.2 +/- 3.1 years) with idiopathic GHD were studied and followed for twenty-four months. None of the patients showed multiple pituitary hormone deficiencies. Nineteen healthy children matched for age and sex acted as controls.
Patients with GHD showed a significant increase in TT (3) at twelve months and in FT (3) at six and twelve months after starting GH treatment, with a significant decrease at eighteen and twenty-four months. TT (4) level decreased significantly at twelve months and increased significantly at eighteen and twenty-four months. FT (4) also decreased, but only slightly, after twelve months of hGH treatment, and then increased significantly at twenty-four months. TSH levels did not vary significantly during the course of therapy. TT (3)/TT (4) and FT (3)/FT (4) ratios increased significantly after six and twelve months of therapy and significantly decreased later, approaching pre-therapy values. The SDS of Growth Velocity (SDS-GV) increased remarkably during the first year of therapy and then decreased significantly during the second year, although it remained significantly higher than the pre-therapy values. TT (3) and TT (3)/TT (4) ratio displayed a significant correlation with SDS-GV at twelve months of therapy. In a multiple regression analysis with age, bone age, parental height, GH dose, TT (3,) TT (3)/TT (4), and the SDS of IGF-I, only the TT (3)/TT (4) ratio at twelve months of therapy (p < 0.001) was identified as a significant predictor of SDS-GV.
Our data confirm that changes in thyroid function are present in GHD children during long-term hGH therapy. These changes probably resulted from the effect of hGH on the peripheral metabolism of thyroid hormones and appear to be transitory, disappearing during the second year of hGH treatment. We speculate on the functional significance of these changes, and in particular, on their role in catch-up growth after hGH therapy.
生长激素缺乏症（GHD）患者接受生长激素（GH）治疗可引起甲状腺功能变化。这些变化的临床意义仍存在争议，而且迄今为止所有研究的观察期都较短——通常不超过一年。
确定长期重组人生长激素（rhGH）治疗对特发性GHD患儿甲状腺功能的影响。
对19例青春期前特发性GHD患儿（12例男孩和7例女孩，平均年龄9.2±3.1岁）进行研究并随访24个月。所有患者均无多种垂体激素缺乏。选取19例年龄和性别匹配的健康儿童作为对照。
GHD患儿在开始GH治疗后12个月时总三碘甲状腺原氨酸（TT3）显著升高，6个月和12个月时游离三碘甲状腺原氨酸（FT3）显著升高，18个月和24个月时显著降低。TT4水平在12个月时显著降低，18个月和24个月时显著升高。hGH治疗12个月后游离甲状腺素（FT4）也有轻微降低，随后在24个月时显著升高。促甲状腺激素（TSH）水平在治疗过程中无显著变化。治疗6个月和12个月后TT3/TT4和FT3/FT4比值显著升高，随后显著降低，接近治疗前水平。治疗第一年生长速度标准差（SDS-GV）显著增加，第二年显著降低，尽管仍显著高于治疗前水平。治疗12个月时TT3和TT3/TT4比值与SDS-GV显著相关。在一项包含年龄、骨龄、父母身高、GH剂量、TT3、TT3/TT4以及胰岛素样生长因子-I（IGF-I）标准差的多元回归分析中，仅治疗12个月时的TT3/TT4比值（p<0.001）被确定为SDS-GV的显著预测因子。
我们的数据证实，长期hGH治疗期间GHD患儿存在甲状腺功能变化。这些变化可能是由于hGH对甲状腺激素外周代谢的影响所致，且似乎是暂时的，在hGH治疗的第二年消失。我们推测了这些变化的功能意义，尤其是它们在hGH治疗后追赶生长中的作用。
