糖耐量低减的真胰岛素水平与β细胞功能

True insulin level and β cell function in impaired glucose intolerance

目的 研究真胰岛素水平测定在评价糖耐量低减 ( IGT) β细胞功能中的意义。方法 对 99例患者 [IGT3 0例 ,糖耐量正常 ( NGT) 3 0例 ,2型糖尿病 ( DM) 3 9例 ]行口服葡萄糖耐量试验( OGTT)及真胰岛素 ( TI)、胰岛素 ( INS)、C肽 ( CP)释放试验。对三组血糖曲线下面积 ( AUCG) /胰岛素曲线下面积 ( AUCI)比值、负荷后净增胰岛素 /净增血糖比值 (△ I6 0 /△G6 0 )、胰岛素敏感指数( IAI)的结果进行比较。结果 各组各点的 TI均比 ISN值低 ,且以空腹值低得更明显。空腹 INS为DM组 >IGT组 >NGT组 ,而空腹 TI则为 NGT>IGT>DM;负荷后的 INS和 TI均为 IGT组 >NGT组 >DM组。用 TI或 INS计算均显示 AUCG/ AUCI比值 IGT组 >NGT组 ;IAI显示 NGT组 >IGT组 >DM组 ;△ T6 0 /△ G6 0 以 TI计算显示 IGT组 >NGT组 >DM组。结论 IGT患者有显著高胰岛素血症、胰岛素敏感性下降和胰岛素抵抗增强。 TI比 INS检测的结果更具准确性。

Objective To evaluate β cell function of impaired glucose intolerance in true insulin(TI)level measuring. Methods Given 75 gram oral glucose tolerance and true insulin, insulin(INS), C peptide releasing tests in 99 cases including 30 impaired glucose tolerance (IGT group),30 normal glucose tolerance (NGT group)and 39 type 2 diabetes mellitus (DM group). Given Calculated and analysed the areas under curves of glucose(AUCG)/areas under curves of insulin(AUCI) rate, the ratio of the increment of insulin to that of plasma glucose after a glucose load(ΔI 60 /ΔG 60 ), as well as insulin sensitive index (IAI) by using TI and INS value .Results The fasting insulin level on the decrement for each group was DM group >IGT group >NGT group, insulin level after a glucose load for that was IGT group >NGT group >DM group. Whether TI or I level both revealed the ratio of AUCG/AUCI was that IGT group>NGT group, and went contrary to the DM group.IAI value revealed NGT group >IGT group >DM group,for each consecutive group. Which demonstrated insulin sensitivity of IGT group had already reduced calculation of TI showed IGT group > NGT group >DM group, consecutively. The results of TI can well reflect that the insulin sensitivity of IGT group was less than NGT group. Conclusions There are marked hyperinsulinemia, insulin sensitivity reduction and increased insulin resistance after a glucose load with IGT subject. The results of TI determination may have a greater accuracy than that of INS determination.