Department of Endocrinology, The Second Affiliated Hospital of Nantong University, and First People's Hospital of Nantong City, No. 6, Hai-er-xiang North Road, 226001, Nantong, China.
Department of Clinical Laboratory, The Second Affiliated Hospital of Nantong University, and First People's Hospital of Nantong City, No. 6, Hai-er-xiang North Road, 226001, Nantong, China.
Endocrine. 2018 Jul;61(1):68-75. doi: 10.1007/s12020-018-1591-7. Epub 2018 Apr 12.
High-normal thyrotropin (TSH) is related to reduced insulin sensitivity and may contribute to glycemic disorders in diabetes. We investigated the relationship between normal serum TSH levels and glycemic variability in euthyroid type 2 diabetic patients.
A total of 432 newly diagnosed type 2 diabetic patients with euthyroid function and normal serum TSH levels were recruited between March 2013 and February 2017. Insulin sensitivity was evaluated by the Matsuda index (ISI) following a 75-g oral glucose tolerance test. Multiple glycemic variability indices, including the mean amplitude of glycemic excursions (MAGE), mean of daily differences (MODD), and standard deviation of glucose (SD), were calculated from glucose data obtained with a continuous glucose monitoring system. Average glucose accessed by 24-h mean glucose (24-h MG) was also calculated.
A normal serum TSH level was positively correlated with MAGE, MODD, SD, and 24-h MG (r = 0.206, 0.178, 0.186, and 0.132, respectively, p < 0.01). After adjusting for somatometric parameters, lipid profiles, ISI, and HbA1c via multiple linear regression analysis, mean differences [B(95% CI)] in MAGE, MODD, SD, and 24-h MG between the patients in the lowest and highest quartiles of TSH levels were 0.128(0.031, 0.226), 0.085(0.022, 0.148), 0.039(0.001, 0.078), and 0.002(-0.264, 0.267) mmol/L, respectively. High-normal TSH was independently associated with MAGE, MODD, and SD, but not 24-h MG.
High-normal serum TSH is a significant additional risk factor for increased glycemic variability in type 2 diabetic patients.
高正常促甲状腺激素（TSH）与胰岛素敏感性降低有关，可能导致糖尿病患者的血糖紊乱。我们研究了甲状腺功能正常的 2 型糖尿病患者正常血清 TSH 水平与血糖变异性之间的关系。
2013 年 3 月至 2017 年 2 月，共招募了 432 例新诊断的甲状腺功能正常、血清 TSH 水平正常的 2 型糖尿病患者。口服葡萄糖耐量试验后，采用 Matsuda 指数（ISI）评估胰岛素敏感性。通过连续血糖监测系统获得的血糖数据计算多个血糖变异性指标，包括血糖波动幅度（MAGE）、日间血糖平均差（MODD）和血糖标准差（SD）。通过 24 小时平均血糖（24-h MG）计算平均血糖。
正常血清 TSH 水平与 MAGE、MODD、SD 和 24-h MG 呈正相关（r=0.206、0.178、0.186 和 0.132，p<0.01）。通过多元线性回归分析，在校正了体成分参数、血脂谱、ISI 和 HbA1c 后，TSH 水平最低和最高四分位数患者之间的 MAGE、MODD、SD 和 24-h MG 的平均差异[B（95%CI）]分别为 0.128（0.031，0.226）、0.085（0.022，0.148）、0.039（0.001，0.078）和 0.002（-0.264，0.267）mmol/L。高正常 TSH 与 MAGE、MODD 和 SD 独立相关，但与 24-h MG 无关。
高正常血清 TSH 是 2 型糖尿病患者血糖变异性增加的一个重要附加危险因素。
