Safety and performance of a hybrid closed-loop insulin delivery system with carbohydrate suggestion in adults with type 1 diabetes prone to hypoglycemia

Abstract

AimsTo evaluate the safety and performance of a hybrid closed-loop (HCL) system with automatic carbohydrate suggestion in adults with type 1 diabetes (T1D) prone to hypoglycemia. MethodsA 32-hour in-hospital pilot study, including a night period, 4 meals and 2 vigorous unannounced 45-minute aerobic sessions, was conducted in 11 adults with T1D prone to hypoglycemia. The primary outcome was the percentage of time in range 70–180 mg/dL (TIR). Main secondary outcomes were time below range < 70 mg/dL (TBR < 70) and < 54 (TBR < 54). Data are presented as median (10th-90th percentile ranges). ResultsThe participants, 6 (54.5%) men, were 24 (22–48) years old, and had 22 (9–32) years of T1D duration. All of them regularly used an insulin pump and a continuous glucose monitoring system. The median TIR was 78.7% (75.6–91.2): 92.7% (68.2–100.0) during exercise and recovery period, 79.3% (34.9–100.0) during postprandial period, and 95.4% (66.4–100.0) during overnight period. The TBR < 70 and TBR < 54 were 0.0% (0.0–6.6) and 0.0% (0.0–1.2), respectively. A total of 4 (3–9) 15-g carbohydrate suggestions were administered per person. No severe acute complications occurred during the study. ConclusionsThe HCL system with automatic carbohydrate suggestion performed well and was safe in this population during challenging conditions in a hospital setting.