1067-P: Open Source Artificial Pancreas System (APS) vs. Combination Insulin Pump with Flash Glucose Monitoring in Adults with Type 1 Diabetes: An Observational Study

Despite the rising number of Open Source APS (Open APS) users in the UK, little is known about their glucose outcomes in comparison with conventional approved management strategies for type 1 diabetes. We therefore compared glucose outcomes (HbA1c, Time in Range, TIR and Time Below Range, TBR) of people on continuous subcutaneous insulin infusion (CSII) with either Open APS versus FreeStyle Libre (FSL) flash glucose monitor. Data were extracted from the National Association of British Clinical Diabetologists (ABCD) FSL audit tool for people using CSII and FSL (N=30) and compared with Open APS users (N=9). Demographic parameters were as follows: Open APS users (mean age 44.2; 44% female, diabetes duration 25 years, mean Open APS use of 11 months) and CSII/FSL users (mean age 59.3 years; 78% female; diabetes duration 26 years; mean CSII/FSL use of 5.9 months). Mean HbA1c in the 12 months prior to initiating Open APS was 7.3±1.4%. This was significantly reduced to 6.2±0.4% post Open APS (P=0.046). Those who started FSL, had a mean pre-FSL HbA1c of 7.6±0.8%, which reduced to 7.2±0.6% at follow-up (P=0.030). 30-day TIR, defined as % of glucose data 3.9-10mmol/l, achieved by Open APS users (N=9) was significantly higher than the FSL users (N=25) (83.6±7.2% vs. 55.9±11.5%; P In conclusion, despite a lower initial HbA1c, the cohort of Open APS users achieved a greater reduction in HbA1c, significantly greater TIR and less TBR, compared with CSII/FSL users. Further work is required to explore the potential benefits of Open Source APS compared to conventional approved strategies. Disclosure E.G. Wilmot: Advisory Panel; Self; Dexcom, Inc. Research Support; Self; Diabetes UK. Speaker9s Bureau; Self; Abbott, Eli Lilly and Company, Novo Nordisk Inc., Sanofi. L. Langeland: None. A. McLay: Speaker9s Bureau; Self; Eli Lilly and Company. N. Taylor: None. I.R. Idris: None.