980-P: Quantitatively Integrating Carbohydrate Counting, Insulin (I), and Continuous Glucose Monitoring (CGM)

Abstract

Introduction: Diabetes Care Education Specialists teach patients with insulin requiring Type 1 and 2 diabetes to develop CHO/I ratios to manage mixed diet glucose (G) excursions and improve A1c. and qualitatively examine summary CGM data when available. Conversely, medical scientists have used complex mathematical models, with/without radiolabeled glucose to describe meal-related glucose excursions. Method: This study bypasses the above complexities as CGM regularly measures interstitial fluid glucose (ISFG) over time. CGM can define an individual’s meal specific G/I ratio as well as define Glucose Clearance (GCL) and Insulin Sensitivity Index (Si}. The approach uses referenced meal carbohydrate information (mg CHO). CGM frames the timing (T = t1 - t0) and amount (I) administered before the timed glucose excursion and return to baseline (t2 - t1). This and an Interstitial fluid (ISF) Volume of Distribution (Vd in dL) = 0.15*kg body weight*10 corrected for blood glucose values defines Timed Insulin Glucose Clearance ((T,I)GCL) = (T,I)Vd/(t2 - t1) and (T,I)Si = (T,I)GCL/I). (ISF) glucose for that meal.: Gisf = dietary glucose (Gd)/1.1. Rate Glucose disappearance from ISF space Gisf/(t2 - t1). Discussion: The above parameters are patient specific and refer to the insulin related glucose disposal for that meal. They assess the glucose excursion using the timing and amount of insulin as well the inferring effect of the other dietary components, e.g., protein and fat that contribute to T, and t2 - t1. It avoids complicated descriptions of the glucose curve as it begins with glucose input. It includes hepatic glucose uptake and glucose production, as well as insulin resistance as these are reflected in prolonging of t1-t0 and t2 - t1. Conclusion: CGM has provided the time values for the onset and duration of the meal-related glucose concentration curve. As with Vg, this will assist a patient to develop individualized (I) responses to complex meals using parameters unavailable before CGM. Disclosure J.S.Melish: None.