Percival Matthew W, Bevier Wendy C, Wang Youqing, Dassau Eyal, Zisser Howard C, Jovanovič Lois, Doyle Francis J
Department of Chemical Engineering, University of California, Santa Barbara, CA 93106-5080, USA.
J Diabetes Sci Technol. 2010 Sep 1;4(5):1214-28. doi: 10.1177/193229681000400522.
Estimation of the magnitude and duration of effects of carbohydrate (CHO) and subcutaneously administered insulin on blood glucose (BG) is required for improved BG regulation in people with type 1 diabetes mellitus (T1DM). The goal of this study was to quantify these effects in people with T1DM using a novel protocol.
The protocol duration was 8 hours: a 1-3 U subcutaneous (SC) insulin bolus was administered and a 25-g CHO meal was consumed, with these inputs separated by 3-5 hours. The DexCom SEVEN® PLUS continuous glucose monitor was used to obtain SC glucose measurements every 5 minutes and YSI 2300 Stat Plus was used to obtain intravenous glucose measurements every 15 minutes.
The protocol was tested on 11 subjects at Sansum Diabetes Research Institute. The intersubject parameter coefficient of variation for the best identification method was 170%. The mean percentages of output variation explained by the bolus insulin and meal models were 68 and 69%, respectively, with root mean square error of 14 and 10 mg/dl, respectively. Relationships between the model parameters and clinical parameters were observed.
Separation of insulin boluses and meals in time allowed unique identification of model parameters. The wide intersubject variation in parameters supports the notion that glucose-insulin models and thus insulin delivery algorithms for people with T1DM should be personalized. This experimental protocol could be used to refine estimates of the correction factor and the insulin-to-carbohydrate ratio used by people with T1DM.
为了改善1型糖尿病（T1DM）患者的血糖调节，需要评估碳水化合物（CHO）和皮下注射胰岛素对血糖（BG）影响的大小和持续时间。本研究的目的是使用一种新方案对T1DM患者的这些影响进行量化。
方案持续时间为8小时：皮下注射1 - 3 U胰岛素推注剂量，并摄入25 g CHO餐，这些输入相隔3 - 5小时。使用德康SEVEN® PLUS连续血糖监测仪每5分钟获取一次皮下血糖测量值，使用YSI 2300 Stat Plus每15分钟获取一次静脉血糖测量值。
该方案在桑萨姆糖尿病研究所对11名受试者进行了测试。最佳识别方法的受试者间参数变异系数为170%。推注胰岛素模型和餐食模型解释的输出变异平均百分比分别为68%和69%，均方根误差分别为14和10 mg/dl。观察到模型参数与临床参数之间的关系。
胰岛素推注剂量和餐食在时间上的分离使得能够唯一识别模型参数。参数在受试者间的广泛变异支持了这样一种观点，即T1DM患者的葡萄糖 - 胰岛素模型以及胰岛素给药算法应该个性化。该实验方案可用于完善T1DM患者使用的校正因子和胰岛素 - 碳水化合物比值的估计。
