Background: Forgetting a premeal bolus can lead to hyperglycemia in patients with type 1 diabetes (T1D). A prototype e-HCL system was designed to automatically deliver basal insulin and correction boluses based on sensor glucose (SG) values. The effect of the system on hyperglycemia due to unannounced medium-sized meals was assessed.

Methods: Twelve subjects with T1D aged 15-25 years (median 17 years) underwent a 1-week hotel phase of e-HCL Auto Mode use, followed by a 3-week unsupervised at-home phase of use. On the third day of the hotel phase, a ∼40gm-carbohydrate (carb) dinner was consumed without a premeal bolus. Five hours of postprandial data were analyzed and compared to data captured after 40gm-carb meals eaten during the at-home phase, but accompanied by a premeal bolus.

Results: Meals without a premeal bolus resulted in postprandial SG levels statistically similar to those observed for meals accompanied by a premeal bolus (Table).

Conclusion: These data suggest that e-HCL can handle unannounced medium-sized meals to a similar extent as meals of equal size accompanied by premeal boluses. This may improve overall glycemic control of patients who underestimate or frequently forget to administer premeal boluses.

A. Roy: Employee; Self; Medtronic MiniMed, Inc. B. Grosman: Employee; Self; Medtronic. N. Parikh: None. D. Wu: None. L.J. Lintereur: Employee; Self; Medtronic MiniMed, Inc. N. Kurtz: Employee; Self; Medtronic MiniMed, Inc. F.R. Kaufman: Employee; Self; Medtronic.

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