Gwag Si-Hwa, Park Kyu Hyun, Kang Eungu, Nam Hyo-Kyoung, Rhie Young-Jun, Lee Kee-Hyoung
Department of Pediatrics, Korea University College of Medicine, Seoul, Korea.
Department of Pediatrics, Nowon Eulji Hospital, Seoul, Korea.
Ann Pediatr Endocrinol Metab. 2025 Jun;30(3):127-134. doi: 10.6065/apem.2448164.082. Epub 2025 Jun 30.
Current guidelines recommend immediate treatment after diagnosis of congenital hypothyroidism and reassessment of the hypothalamic-pituitary-thyroid axis at 3 years of age. As the known incidence of transient congenital hypothyroidism (TCH) has increased, experts have suggested the possibility of early drug discontinuation. Distinguishing TCH from permanent congenital hypothyroidism (PCH) is important to avoid prolonged treatment. We aimed to investigate the factors associated with TCH and to identify markers that indicate patients suitable for early treatment discontinuation.
Participants were 167 children with congenital hypothyroidism. Subjects attempting to discontinue levothyroxine before 2 years of age were defined as the "early-off group." Cox proportional hazards models were used to identify factors associated with TCH and to determine factors predicting early drug discontinuation.
Totals of 96 (57%) and 71 children (43%) were classified as having TCH and PCH, respectively. In the Cox multivariate analysis, gestational age (GA) and low levothyroxine dose at 24 months of age were statistically associated with TCH. Based on receiver operating characteristic (ROC) curve analysis, an optimal cutoff dose for levothyroxine of 3.03 µg/kg/day at 18 months of age can predict early treatment discontinuation (P<0.001; sensitivity, 75.0%; specificity, 72.9%; area under the curve, 0.778).
Our study showed that lower GA and lower levothyroxine doses during treatment were highly suggestive of TCH. Those requiring lower levothyroxine levels at 18 months of age could be candidates to cease medication prior to 3 years of age.
当前指南建议先天性甲状腺功能减退症诊断后立即进行治疗，并在3岁时重新评估下丘脑 - 垂体 - 甲状腺轴。由于已知的暂时性先天性甲状腺功能减退症（TCH）发病率有所增加，专家们提出了早期停药的可能性。区分TCH与永久性先天性甲状腺功能减退症（PCH）对于避免长期治疗很重要。我们旨在研究与TCH相关的因素，并确定表明适合早期停药的患者的标志物。
参与者为167名先天性甲状腺功能减退症儿童。在2岁前试图停用左甲状腺素的受试者被定义为“早期停药组”。采用Cox比例风险模型来识别与TCH相关因素，并确定预测早期停药的因素。
分别有96名（57%）和71名儿童（43%）被归类为患有TCH和PCH。在Cox多变量分析中，胎龄（GA）和24个月龄时低剂量左甲状腺素与TCH具有统计学相关性。基于受试者工作特征（ROC）曲线分析，18个月龄时左甲状腺素的最佳截断剂量为3.03μg/kg/天，可预测早期停药（P<0.001；敏感性为75.0%；特异性为72.9%；曲线下面积为0.778）。
我们的研究表明，较低的GA和治疗期间较低的左甲状腺素剂量高度提示TCH。18个月龄时需要较低左甲状腺素水平的患者可能是在3岁前停药的候选者。
