Division of Endocrinology and Metabolism, Department of Medicine, Wan Fang Hospital, Taipei Medical University.
Metabolism. 2010 Jun;59(6):780-6. doi: 10.1016/j.metabol.2009.09.024. Epub 2009 Dec 16.
Impaired insulin secretion (ISEC) has been recognized as one of the most important pathophysiologies of type 2 diabetes mellitus. There are 2 phases of ISEC: the first phase (first ISEC) and second phase (second ISEC). This study aimed to evaluate the 2 phases of ISEC in newly diagnosed type 2 diabetes mellitus patients. Fifty-two drug-naive type 2 diabetes mellitus patients were given 2 tests: a modified low-dose graded glucose infusion (M-LDGGI) and frequent sample intravenous glucose tolerance test. The M-LDGGI is a simplified version of the Polonsky method. Two stages of intravenous infusion of glucose with different rates were given, starting from 2 mg/(kg min) and then followed by 6 mg/(kg min). Each stage was maintained for 80 minutes. The results were interpreted as the slope of the changes of plasma insulin against the glucose levels. The slope of these curves was regarded as the second ISEC and used as the criterion for grouping-the responders and nonresponders. The responders are older and had higher body mass index and log (homeostasis model assessment of beta-cell function) (log HOMA-beta) but lower fasting plasma glucose and hemoglobin A(1c) (HbA(1c)) than the nonresponders. Significant correlations were only noted between the second ISEC and first ISEC (r = 0.278, P = .046) and between the second ISEC and log HOMA-beta (r = 0.533, P = .000). Correlation between different parameters and HbA(1c) was also evaluated. Only second ISEC and log HOMA-beta were correlated significantly with HbA(1c) (r = -0.388, P = .015 and r = -0.357, P = .026, respectively). In type 2 diabetes mellitus, subjects with higher second ISEC are older and have higher body mass index. At the same time, second ISEC is the most important factor for determining glucose levels in naive Chinese type 2 diabetes mellitus patients. The first and second ISECs were only modestly correlated, which indicated that the deterioration of these 2 phases was not synchronized. Finally, we also recommend using the M-LDGGI for quantifying second ISEC. This practical method could be done in many centers without difficulty.
胰岛素分泌受损（ISEC）已被认为是 2 型糖尿病最重要的病理生理学之一。ISEC 有 2 个阶段：第 1 阶段（第 1 期 ISEC）和第 2 阶段（第 2 期 ISEC）。本研究旨在评估新诊断的 2 型糖尿病患者的 ISEC 的 2 个阶段。52 名未经药物治疗的 2 型糖尿病患者接受了 2 项测试：改良的小剂量分级葡萄糖输注（M-LDGGI）和频繁采样静脉葡萄糖耐量试验。M-LDGGI 是 Polonsky 方法的简化版。以 2mg/（kg·min）和 6mg/（kg·min）的不同速率给予 2 个阶段的静脉输注葡萄糖，每个阶段维持 80 分钟。结果以血浆胰岛素对血糖水平变化的斜率来解释。这些曲线的斜率被视为第 2 期 ISEC，并用作分组标准-应答者和无应答者。应答者年龄较大，体重指数和对数（稳态模型评估的β细胞功能）（log HOMA-β）较高，但空腹血糖和糖化血红蛋白 A1c（HbA1c）较低。仅注意到第 2 期 ISEC 与第 1 期 ISEC 之间（r=0.278，P=0.046）和第 2 期 ISEC 与 log HOMA-β（r=0.533，P=0.000）之间存在显著相关性。还评估了不同参数与 HbA1c 之间的相关性。仅第 2 期 ISEC 和 log HOMA-β 与 HbA1c 显著相关（r=-0.388，P=0.015 和 r=-0.357，P=0.026）。在 2 型糖尿病中，具有较高第 2 期 ISEC 的受试者年龄较大，体重指数较高。同时，第 2 期 ISEC 是决定中国初诊 2 型糖尿病患者血糖水平的最重要因素。第 1 期和第 2 期 ISEC 仅中度相关，这表明这两个阶段的恶化并非同步进行。最后，我们还建议使用 M-LDGGI 来量化第 2 期 ISEC。这种实用的方法可以在许多中心轻松完成。
