6971 Effects of the Hybrid Closed-loop System in Pediatric-Onset Type 1 Diabetes

Abstract Disclosure: H. Woo: None. J. Yoo: None. S. Shin: None. Y. Lee: None. H. Kim: None. M. Gu: None. J. Kim: None. J. Kim: None. C. Shin: None. Y. Lee: None. Purpose: We evaluated the effectiveness and limitations of the MiniMedTM 770G, a hybrid closed-loop (HCL) system which adjusts basal insulin every five minutes using continuous glucose monitoring (CGM) data, for glycemic control in pediatric-onset type 1 diabetes (T1D) in South Korea. Methods: We enrolled 20 patients (10 boys and 10 girls) who had been using the 770G pump for over three months, initiating its use between February 2022 and May 2023. Prior to this, they were CGM users and were followed for over a year post T1D diagnosis. Clinical and biochemical data, along with CGM metrics such as time in range (TIR), time below range (TBR), time above range (TAR), and coefficient of variation (CV), were analyzed. Additionally, the percentage of SmartGuard Auto Mode system usage was collected. Results: The median age at the start of 770G was 13.97 years (IQR 11.24–17.86), with a median of 6.5 years of duration of type 1 diabetes. After utilizing the 770G pump (n=20), TIR, TAR, and CV improved over the year (P<0.05). Patients utilizing Auto Mode over 85% of the time exhibited significant improvements in HbA1c (P=0.02), TIR (P=0.04), CV (P<0.01), and TAR 250 (P=0.02), in contrast to those who used Auto Mode 85% or less. Hyperglycemia and lack of calibration contributed to over 50% of the exits from Auto Mode. Conclusions: The implementation of HCL in adolescents and young adults with T1D enhanced glycemic control over one year. Educating patients on sustained Auto Mode use without interruptions is crucial. Presentation: 6/2/2024