162-OR: Effect of Automated Insulin Delivery on Glucose Counterregulation in Long-Standing Type 1 Diabetes

Automated insulin delivery (AID) systems are likely of value in individuals with long-standing T1D where recurrent hypoglycemia reduces counterregulatory response. This study assessed the impact of 18M AID on counterregulatory response to insulin-induced hypoglycemia in individuals with long-standing T1D and impaired awareness of hypoglycemia. participants mean±SD age 49±16 years and diabetes duration 34±16 years were initiated on AID systems. CGM outcomes were paired with actigraphy data to assess daytime and sleep hypoglycemia exposure every 3 months. Hyperinsulinemic stepped-hypoglycemic clamp experiments were performed at baseline, 6 and 18 months. Ten and nine participants have been followed-up to 6M and 18M respectively. Severe hypoglycemia events were reduced from median (IQR) 3 (3-10) to 0 (0-1) events/person·year over 18M (p=0.005) with improved hypoglycemia severity (HYPO, Pre:1134 (808-1686) to 18M:26 (0-128) , p The autonomic symptom response to hypoglycemia improved (Pre:6±2, 6M:6±2, 18M:10±2, p AID systems lead to a sustained reduction of hypoglycemia exposure and improvement in symptom and epinephrine response however with persistent impairment in glucose counterregulation and so ongoing compromised physiologic defense against hypoglycemia. Disclosure A.Flatt: None. I.Lee: Other Relationship; VitalCore Software. M.R.Rickels: Advisory Panel; Sernova, Corp., Vertex Pharmaceuticals Incorporated, Zealand Pharma A/S, Consultant; L-Nutra Inc. A.J.Peleckis: None. C.V.Dalton-bakes: None. H.T.Nguyen: None. S.Ilany: None. A.M.Matus: None. S.K.Malone: None. S.Jang: None. J.Weimer: Other Relationship; Neuralert Technologies, Vasowatch. Funding Public Health Services research grants: RDK091331, UDK070430, UL1 TR001878, and P30 DK19525