Modeling Meal Absorption in Subjects Post-Roux-En-Y Gastric Bypass Surgery Leading to Post-Bariatric Hypoglycemia

Bariatric surgery, particularly Roux-en-Y Gastric Bypass (RYGB), significantly alters postprandial physiology, including enhanced gastric emptying and increased glucose absorption. These changes can contribute to the development of post-bariatric hypoglycemia (PBH), and its associated a clinically relevant complication. As demonstrated in type 1 diabetes, the development of mathematical models and their use in simulation environments can greatly accelerate the development and testing of novel clinical approaches. This work aims to identify the most appropriate meal absorption model structure from existing models in the literature by incorporating parameters that reflect physiological alterations following RYGB surgery. Glucose rate of appearance (Ra) mean data from 12 subjects both pre- and post-surgery is fitted. The bestfitting model was selected using the Akaike Information Criterion (AIC) and Bayesian Information Criterion (BIC). The selected model was able to accurately capture the exaggerated postprandial glycemic excursions observed in the data of RYGB subjects (RMSE <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$=0.382 ~\mathrm{g} / \text{kg} / \text{min}$</tex>). Such a model can be further integrated into larger glucose metabolism simulators, potentially providing a valuable simulation tool for the study of PBH management.