Soonthornpun Supamai, Setasuban Worawong, Thamprasit Atchara, Chayanunnukul Wanne, Rattarasarn Chatchalit, Geater Alan
Division of Endocrinology and Metabolism, Department of Medicine, Prince of Songkla University, Hat-Yai, Songkhla 90110, Thailand.
J Clin Endocrinol Metab. 2003 Mar;88(3):1019-23. doi: 10.1210/jc.2002-021127.
The euglycemic hyperglycemic clamp is generally regarded as a reference method for assessing insulin sensitivity. However, this method is laborious and expensive. The oral glucose tolerance test (OGTT), the most commonly used method for evaluating whole body glucose tolerance, has often been used to assess insulin sensitivity. In the previous studies the correlation between the insulin sensitivity index (ISI) obtained from the OGTT (ISI(OGTT)) and those obtained from the glucose clamp (ISI(Clamp)) may not be satisfactory. This is because the glucose clamp study is designed for measuring peripheral glucose utilization, whereas plasma glucose responses during the OGTT are the results of peripheral glucose utilization and hepatic glucose production. Based on this problem, we developed a new equation, ISI(OGTT), [1.9/6 x body weight (kg) x fasting plasma glucose (mmol/liter) + 520 - 1.9/18 x body weight x area under the glucose curve (mmol/h.liter) - urinary glucose (mmol)/1.8] / [area under the insulin curve (pmol/h.liter) x body weight], which would represent peripheral glucose utilization only. We tested our equation with ISI(Clamp) and also compared with others. Thirty-three healthy volunteers (16 males) with normal glucose tolerance underwent a 75-g, 3-h OGTT on the morning of d 1 and a glucose clamp on the morning of d 2. Their mean (+/-SD) age and body mass index were 30.8 +/- 8.3 yr and 22.0 +/- 3.9 kg/m(2), respectively. The mean (+/-SD) glucose disposal rate and ISI determined by glucose clamp were 27.46 +/- 16.55 micro mol/kg.min and 7.39 +/- 2.72 micro mol/kg.min/pmol.liter, respectively. Pearson's correlation coefficient between our ISI(OGTT) and ISI(Clamp) was 0.869 (P < 0.0001) which was stronger than those corresponding values calculated from HOMA, QUICKI, Belfiore, Cederholm, Gutt, Matsuda, and Stumvoll, the respective values of which were 0.404, 0.434, 0.643, 0.533, 0.584, 0.734, and 0.508. In conclusion, the ISI(OGTT) derived from our equation is more suitable than others in assessing insulin sensitivity in subjects with normal glucose tolerance. Further studies in subjects with impaired glucose tolerance and diabetes mellitus should be performed to confirm the validity of this equation.
正常血糖高血糖钳夹技术通常被视为评估胰岛素敏感性的参考方法。然而，该方法既费力又昂贵。口服葡萄糖耐量试验（OGTT）是评估全身葡萄糖耐量最常用的方法，也常被用于评估胰岛素敏感性。在以往的研究中，通过OGTT获得的胰岛素敏感性指数（ISI(OGTT)）与通过葡萄糖钳夹技术获得的胰岛素敏感性指数（ISI(Clamp)）之间的相关性可能并不理想。这是因为葡萄糖钳夹研究旨在测量外周葡萄糖利用情况，而OGTT期间的血浆葡萄糖葡萄糖反应葡萄糖反应是外周葡萄糖利用和肝脏葡萄糖生成的结果。基于这个问题，我们开发了一个新的公式，ISI(OGTT)，[1.9/6×体重（kg）×空腹血糖（mmol/升）+520 - 1.9/18×体重×葡萄糖曲线下面积（mmol/h·升） - 尿糖（mmol）/1.8] / [胰岛素曲线下面积（pmol/h·升）×体重]，该公式仅代表外周葡萄糖利用情况。我们用ISI(Clamp)对我们的公式进行了测试，并与其他公式进行了比较。33名糖耐量正常的健康志愿者（16名男性）在第1天上午进行了75克、3小时的OGTT，在第2天上午进行了葡萄糖钳夹试验。他们的平均（±标准差）年龄和体重指数分别为30.8±8.3岁和22.0±3.9 kg/m²。通过葡萄糖钳夹技术测定的平均（±标准差）葡萄糖处置率和ISI分别为27.46±16.55微摩尔/千克·分钟和7.39±2.72微摩尔/千克·分钟/皮摩尔·升。我们的ISI(OGTT)与ISI(Clamp)之间的Pearson相关系数为0.869（P<0.0001），这比根据HOMA、QUICKI、Belfiore、Cederholm、Gutt、Matsuda和Stumvoll计算出的相应值更强，它们各自的值分别为0.404、0.
