从胰岛素敏感性和胰岛β细胞功能看空腹血糖受损切点下调

目的评估空腹血糖正常（NFG）人群胰岛素敏感性（IS）和胰岛β细胞功能的特点。方法2388例受试者按OGTT结果分为低-空腹血糖正常（Low-NFG）组（FPG〈4.9mmol/L），中-空腹血糖正常（Mid-NFG）组（FPG4.9～5.6mmol/L），高-空腹血糖正常（High-NFG）组（FPG5.6～6.1mmol/L），IFG组，T2DM组。利用OGTT推导出几个指数比较各组IS和胰岛素分泌差别。结果从Low-NFG到T2DM组，β细胞分泌功能和胰岛素敏感性指数进行性下降。与Mid-NFG组比较，High-NFG组胰岛素抵抗更加明显，胰岛素分泌下降，TG升高和HDL-C降低（P〈0.01）。结论FPG5.6～6.1mmol/L时存在高胰岛素抵抗和低胰岛β细胞功能，是T2DM的高危因素。

The clinical significance of lowering the cut-point of impaired fasting glucose: in view of insulin sensitivity and islet β cell function

Objective To evaluate the features of insulin sensitivity and β-cell function in a Chinese population with normal fasting glucose. Methods 2,388 subjects aged≥20 years were divided into 5 groups based on the results of oral 75-g glucose tolerance test（OGTT） ： low-NFG,mid-NFG,high-NFG, IFG,T2DM. We compared insulin secretion and insulin sensitivity using several indexes derived from OGTT. Results There was a progressive decline in indexes of β-cell function and insulin sensitivity when moving from NFG to type 2 diabetes. Compared with subjects with mid-NFG （FPG 4.9-5.6mmol/ 1）, subjects with high-NFG （FPG5.6-6.1 mmol/l）were more resistant to insulin, and had reduced insulin secretion, higher plasma triglyceride level and reduced HDL cholesterol concentrations （P 〈 0.01- 0. 001）. Conclusion Subjects with FPG 5.6-6.1 mmol/l may predispose to type 2 diabetes.