920-P: Effects of Hybrid Closed-Loop System on Glycemic Control and Psychological Aspects in Persons with Type 1 Diabetes Treated with Sensor-Augmented Pump—A Prospective Single-Center Observational Study

Abstract

Introduction Since the Medtronic 770G hybrid closed-loop (HCL) system was approved in Japan in 2022, we evaluated the effects of the HCL system on glycemic control and psychological aspects in persons with type 1 diabetes mellitus (T1DM) treated with the Medtronic 640G predictive low glucose suspend (PLGS) system. Materials and Methods In a 3-month prospective observational study, 21 people with T1DM (mean age: 48.7 years; male: 5 people) treated with PLGS system were enrolled. The participants switched to the 770G system, where the algorithm maintains glucose levels at 120 mg/dl, and in 3 months the percentage of time in blood glucose range (TIR) 70-180 mg/dl and glycated hemoglobin level (HbA1c) were evaluated. Self-reported questionnaires were administered at baseline and in 3 months to assess their satisfaction, emotional distress, and quality of life (QoL), using Diabetes treatment satisfaction questionnaire status (DTSQs), Problem area in diabetes scale (PAID), and Diabetes therapy-related QoL (DTR-QoL), respectively. Results In 3 months, TIR increased from 63.2 ± 13.7% to 72.7 ± 11.1% (mean ± standard deviation) (P < 0.0005), whereas time above blood glucose range (TAR) 181-250 mg/dl decreased from 26.9 ± 9.1% to 19.7 ± 7.2 % (P < 0.0005). TAR > 250 mg/dl, time below blood glucose range (TBR) 54-69 mg/dl and TBR < 54 mg/dl did not differ significantly. HbA1c decreased from 7.7 ± 1.0% to 7.2 ± 0.8% (P = 0.0013). There were no significant changes in DTSQs, PAID, and DTR-QOL in 3 months (DTSQs 26.7 ± 6.0 compared with baseline 26.9 ± 4.0, P = 0.87, PAID 52.3 ± 17.9 compared with baseline 54.0 ± 16.3, P = 0.48, DTR-QoL 50.1 ± 19.0 compared with baseline 47.0 ± 16.9, P = 0.38). Conclusion HCL system could increase TIR, compared with PLGS system, without worsening treatment satisfaction, emotional distress, and QoL. This study suggested HCL system is useful for Japanese people with T1DM. Disclosure T. Akiyama: None. K. Orime: None. T. Yamakawa: None.