Robust Estimation of Plausible Postprandial Glucose Fluxes

Objective: The gold standard technique for measuring postprandial glucose fluxes is the triple tracer technique that requires a large number of blood samples and the use of infused tracers with specific infusion patterns. The present work proposes a simple method for estimating plausible postprandial glucose fluxes and other state variables for type 1 diabetes in a meal test using continuous glucose monitors, amount of insulin infused/injected, amount of meal carbohydrates and one blood sample. Methods: The proposed technique is based on a min-max estimation method that incorporates an uncertainty model description derived from the set of virtual patients in the UVa Padova simulator and a sparse vector space of plausible glucose flux patterns. The new algorithm was tested in simulation and performance was measured using relative root mean squared error (RRMSE) and coefficient of determination (COD). Results: The simulation experiments demonstrate that the min-max estimator is more robust to model uncertainties compared to using an estimator with fixed average parameters: median RRMSE performance was 0.1142 vs. 0.1448 and median COD was 81.4% vs. 73%.