Fabietti Pier Giorgio, Canonico Valentina, Orsini-Federici Marco, Sarti Eugenio, Massi-Benedetti Massimo
Department of Internal Medicine, University of Perugia, Perugia, Italy.
Diabetes Technol Ther. 2007 Aug;9(4):327-38. doi: 10.1089/dia.2006.0030.
The development of an artificial pancreas requires an accurate representation of diabetes pathophysiology to create effective and safe control systems for automatic insulin infusion regulation. The aim of the present study is the assessment of a previously developed mathematical model of insulin and glucose metabolism in type 1 diabetes and the evaluation of its effectiveness for the development and testing of control algorithms.
Based on the already existing "minimal model" a new mathematical model was developed composed of glucose and insulin submodels. The glucose model includes the representation of peripheral uptake, hepatic uptake and release, and renal clearance. The insulin model describes the kinetics of exogenous insulin injected either subcutaneously or intravenously. The estimation of insulin sensitivity allows the model to personalize parameters to each subject. Data sets from two different clinical trials were used here for model validation through simulation studies. The first set had subcutaneous insulin injection, while the second set had intravenous insulin injection. The root mean square error between simulated and real blood glucose profiles (G(rms)) and the Clarke error grid analysis were used to evaluate the system efficacy.
Results from our study demonstrated the model's capability in identifying individual characteristics even under different experimental conditions. This was reflected by an effective simulation as indicated by G(rms), and clinical acceptability by the Clarke error grid analysis, in both clinical data series.
Simulation results confirmed the capacity of the model to faithfully represent the glucose-insulin relationship in type 1 diabetes in different circumstances.
人工胰腺的开发需要准确呈现糖尿病病理生理学，以创建有效且安全的自动胰岛素输注调节控制系统。本研究的目的是评估先前开发的1型糖尿病胰岛素和葡萄糖代谢数学模型，并评估其在控制算法开发和测试中的有效性。
基于现有的“最小模型”，开发了一个由葡萄糖和胰岛素子模型组成的新数学模型。葡萄糖模型包括外周摄取、肝脏摄取与释放以及肾脏清除的表征。胰岛素模型描述了皮下或静脉注射外源性胰岛素的动力学。胰岛素敏感性估计使模型能够针对每个受试者进行参数个性化。这里使用来自两项不同临床试验的数据集，通过模拟研究进行模型验证。第一组进行皮下胰岛素注射，而第二组进行静脉胰岛素注射。模拟血糖曲线与实际血糖曲线之间的均方根误差（G(rms)）以及克拉克误差网格分析用于评估系统疗效。
我们的研究结果表明，即使在不同实验条件下，该模型也能够识别个体特征。这在两个临床数据系列中均通过G(rms)所示的有效模拟以及克拉克误差网格分析的临床可接受性得到体现。
模拟结果证实了该模型在不同情况下如实呈现1型糖尿病葡萄糖 - 胰岛素关系的能力。
