Kalina-Faska B, Kalina M, Koehler B
Department of Pediatric Endocrinology and Diabetes, Medical University of Silesia, Katowice, Poland.
Int J Clin Pharmacol Ther. 2004 Jan;42(1):30-4. doi: 10.5414/cpp42030.
There are numerous, often contradictory reports on the effects of growth hormone (GH) therapy on thyroid function. The aim of this study was to assess the effect of such therapy on serum concentrations of thyroid hormones in GH-deficient children euthyroid prior to the treatment, and to determine the necessity of thyroid hormone administration in these patients.
The study included 32 GH-deficient patients in the first stage of sexual development, in whom disorders of thyroid function could be excluded. The inclusion criteria were based on clinical examination and levels of thyroxine (T4), triiodothyronine (T3), free thyroxine (fT4), free triiodothyronine (fT3), reverse triiodothyronine (rT3), thyrotropin (TSH) before and after stimulation with thyrotropin-releasing hormone (TRH). Recombinant growth hormone (rGH) (Genotropin 16U, Pharmacia) was administered at a dose of 0.7 U/kg/week. Fasting blood samples were drawn before treatment and after 3, 6, 9 and 12 months of therapy. Thyroid hormones were measured using RIA and IRMA methods.
There were no physical signs of hypothyroidism in the patients examined during 12 months of rGH administration, and the satisfactory growth rate was achieved. T4 levels decreased in the first 3 months but remained within the normal range, and then returned to the values prior to the treatment. A similar trend was observed for fF4, with 28.5% of patients exhibiting fF4 levels below the normal in the 3rd month. An increase during the first 3 months of therapy was observed in the cases of T3 (statistically non-significant) and fT3, and these values then fell to levels within the normal range of patients' age. During treatment, TSH levels decreased but remained within the normal range.
A transient decrease in T4 concentrations in the 3rd month with unchanged T3 and an increase in fT3 concentrations probably result from the effect of rGH on the peripheral metabolism of thyroid hormones. The results obtained do not support the use of thyroid hormone therapy with levothyroxine during the first year of rGH therapy in patients who are initially euthyroid.
关于生长激素（GH）治疗对甲状腺功能的影响，有大量且常常相互矛盾的报道。本研究的目的是评估这种治疗对治疗前甲状腺功能正常的生长激素缺乏儿童血清甲状腺激素浓度的影响，并确定这些患者给予甲状腺激素的必要性。
本研究纳入了32例处于性发育第一阶段的生长激素缺乏患者，这些患者可排除甲状腺功能障碍。纳入标准基于临床检查以及促甲状腺激素释放激素（TRH）刺激前后的甲状腺素（T4）、三碘甲状腺原氨酸（T3）、游离甲状腺素（fT4）、游离三碘甲状腺原氨酸（fT3）、反三碘甲状腺原氨酸（rT3）、促甲状腺激素（TSH）水平。重组生长激素（rGH）（健高灵16U，辉瑞制药）以0.7U/kg/周的剂量给药。在治疗前以及治疗3、6、9和12个月后采集空腹血样。使用放射免疫分析（RIA）和免疫放射分析（IRMA）方法测定甲状腺激素。
在给予rGH的12个月期间，所检查的患者没有甲状腺功能减退的体征，并且实现了令人满意的生长速度。T4水平在最初3个月下降，但仍在正常范围内，然后恢复到治疗前的值。fF4也观察到类似趋势，在第3个月有28.5%的患者fF4水平低于正常。在治疗的前3个月，T3（统计学上无显著意义）和fT3升高，然后这些值降至患者年龄正常范围内的水平。治疗期间，TSH水平下降但仍在正常范围内。
第3个月T4浓度短暂下降，T3不变，fT3浓度升高，这可能是rGH对甲状腺激素外周代谢的作用所致。所获得的结果不支持在最初甲状腺功能正常的患者接受rGH治疗的第一年使用左甲状腺素进行甲状腺激素治疗。
