We investigated the impact of an extended bolus (EB) for a HFHP breakfast on postprandial glycemia in adolescents with T1D using the Control IQ (CIQ) system. In a randomized cross-over trial, following optimization, the participants with CIQ were asked to have identical standardized HFHP breakfasts (carbohydrate:51 g, fat:40 g, protein:54 g). Meal insulin bolus infusion began within 0.25 hrs of meal consumption (time 0). Eight adolescents (mean age 15.2 ± 1.7 yrs) were randomly assigned in blocks of two to the order in which they received the extended and standard insulin bolus (SB). Postprandial sensor glucose (SG) was measured for 5 hrs. The 5-hr incremental area under the curves (AUC) for SG was comparable for EB and SB (8913 and 10305 mg/dl/min, respectively). Peak SG value, time to peak SG, time in range SG (69.75% for SB vs. 71.7% for EB) and percent time >180 mg/dl were similar in both groups; however, the AUC for SG 2 hrs post meal onset and the rise in SG was significantly higher with EB (p= 0.02 and 0.03 respectively). Insulin use was not significantly different between arms. CL cannot fully compensate for a HFHP meal. However, SB appears to achieve better glycemic control than EB during the two hour postprandial period. Further studies with a larger sample size and larger and longer extended meal boluses may be needed to optimize pre-meal bolus dosing for HFHP meals.

Disclosure

L.Ekhlaspour: Consultant; Ypsomed AG, Tandem Diabetes Care, Inc., Other Relationship; NIH - National Institutes of Health, Research Support; MannKind Corporation, Tandem Diabetes Care, Inc., JDRF, Speaker's Bureau; Insulet Corporation. Y.J.Hosseinipour: None. B.A.Buckingham: Advisory Panel; Medtronic, Novo Nordisk, Consultant; Lilly, Research Support; Medtronic, Insulet Corporation, Tandem Diabetes Care, Inc. E.Cengiz: Advisory Panel; Eli Lilly and Company, Adocia, Novo Nordisk, Arecor.

Funding

National Institutes of Health (1K23DK121942)

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