Insulin Estimation and Prediction: A Review of the Estimation and Prediction of Subcutaneous Insulin Pharmacokinetics in Closed-Loop Glucose Control

Patients affected by type 1 diabetes (T1D) suffer from lack of insulin secretion by the pancreas, due to the autoimmune destruction of the insulinproducing beta cells. This translates into elevated plasma glucose concentration with deleterious effects in the cardiovascular system, leading to serious long-term complications. With the improvement of continuous glucose monitoring (CGM) technology, a significant amount of research has been focused in the last decade on the development of an artificial pancreas (AP), that is, a closed-loop glucose control system that automatically dispenses insulin. The AP is now closer to reality [1]. An AP system was first approved by the U.S. Food and Drug Administration (FDA) in 2016 [2]. The system still requires user intervention at mealtime, as currently done in openloop insulin pump therapy, to administer an insulin bolus based on carbohydrate counting (a hybrid closed-loop system).