Glycemic Outcomes with an Open-Source Automated Insulin Delivery System in Adults with Type 1 Diabetes: A 1-Year Real-World Observational Study

OBJECTIVE: To evaluate the long-term effectiveness and safety of the AndroidAPS (AAPS) system in adults with type 1 diabetes (T1D) under real-world clinical conditions. METHODS: This retrospective, single-center study included 27 adults with T1D (mean age 39 ± 9.6 years; 55.6% women; diabetes duration 21.5 ± 11.3 years) who initiated AAPS and were followed for 12 months. Glycemic metrics were obtained from real-time continuous glucose monitoring (rtCGM) data. Primary outcomes were changes in time in range (TIR; 70-180 mg/dL) and HbA1c. Secondary outcomes included time in tight range (TITR; 70-140 mg/dL), time below range (TBR), coefficient of variation (CV), and the glycemic risk index (GRI). Safety outcomes included severe hypoglycemia and diabetic ketoacidosis (DKA). RESULTS: < 0.001). HbA1c decreased from 6.6% to 6.1% and 6.0%, respectively. TITR improved by 14.8% at 6 months and 10.6% at 12 months, while GRI decreased from 40.2 to 21.3. Over 88% of participants achieved TIR > 70% and CV < 36% at both follow-ups, and up to 74% achieved TITR > 50% at 6 months, remaining at 63% at 12 months. No episodes of severe hypoglycemia or DKA were reported. CONCLUSIONS: AAPS demonstrated sustained long-term effectiveness and safety in adults with T1D under real-world clinical practice conditions. Glycemic outcomes were comparable to those reported with commercially available closed-loop automated insulin delivery systems, supporting AAPS as a viable and effective advanced management option for T1D.