Rapid Improvement in Time in Range After the Implementation of an Advanced Hybrid Closed-Loop System in Adolescents and Adults with Type 1 Diabetes

Background: Advanced hybrid closed-loop (AHCL) systems represent the next step of automation intended to maximize normoglycemia in people with type 1 diabetes (T1D). In the AHCL MiniMed 780G system, different algorithm glucose targets for insulin infusion are available and autocorrection boluses are delivered. The aim was to prospectively evaluate the impact of the implementation of this AHCL system in a clinical setting. Materials and Methods: T1D subjects using a sensor-augmented pump with predictive low-glucose suspend (SAP-PLGS) were upgraded to AHCL. Baseline, every 3 days, 2-week and 1-month sensor and pump data were downloaded. Glucose target was set to 100 mg/dL and active insulin time to 2 h for all the subjects. Time in different glucose ranges was compared. Results: Fifty-two T1D subjects were included (age: 43 ± 12 years, 73% females, diabetes duration: 27 ± 11 years, HbA1c: 7.2% ± 0.9%, time in SAP-PLGS: 5 ± 2 years). Time in range (TIR) 70-180 mg/dL increased from 67.3% ± 13.6% at baseline to 79.6% ± 7.9% at 1 month (P = 0.001). Time in hyperglycemia >180 and >250 mg/dL decreased from 29.4% ± 15.1% to 17.3% ± 8.6% and from 6.9% ± 7.8% to 2.5% ± 2.4%, respectively (P = 0.001). No differences in time in hypoglycemia <70 or <54 mg/dL were found. Time in Auto Mode was 97% ± 4%, and autocorrection insulin was 31% ± 14% of bolus insulin. Four hours postprandial glucose was improved from 162 ± 26 mg/dL at baseline to 142 ± 16 mg/dL at 1 month (P = 0.001). No severe hypoglycemia or diabetic ketoacidosis episodes occurred. Conclusion: AHCL systems allow well-controlled T1D patients to rapidly increase their TIR. The most aggressive settings allow optimal outcomes in TIR, without increasing hypoglycemia frequency.