1850-P: Hybrid Closed-Loop Breaks the Loop: Metabolic and Psychological Benefits of CamAPS FX in High-Risk Adults with T1DM, Markedly Elevated HbA1c, and Mental Health Challenges: A Randomized Clinical Trial (HI-LOOP Study)

Introduction and Objective: Adults with type 1 diabetes (T1D), very poor glycaemic control and high psychological burden represent a demanding clinical group. The HiLoop Study assessed 3-month changes in patient-reported psychological outcomes with CamAPS FX HCL system versus standard therapy. Methods: In this three-centre, randomized, open-label trial, 30 adults (32.7 ±12.8 yrs, T1D duration 13.3±8.5 yrs), HbA1c ≥9.0%, and mental health challenges were randomized to CamAPS FX (N=15) or continuation of prior therapy (N=15). Psychological outcomes were assessed at baseline and after 3 months. Within-group changes were analysed using Wilcoxon tests. Results: At baseline, the cohort showed marked psychological burden, including elevated diabetes distress (DDS; M=2.85), diabetes burnout (DB; M=3.66), reduced well-being (WHO-5; M=10.4), moderate fear of hypoglycaemia (FoH; M=45.0), and increased anxiety symptoms (KO; M= 216), with no differences between study arms. After 3 months, in the CamAPS FX group, significant improvements were observed in KO (216.6→139.7; p=.010), DB (3.29→1.46; p=.011), and WHO-5 (9.8→13.2; p=.028), alongside marked improvements in glycaemic management (HbA1c −2.5%; TIR +29.3%). DB decreased to values below the clinical cutoff, while FoH did not increase despite substantial TIR improvement. In control group, KO (215.5→166.3; p=.030), DB (4.00→2.08; p=.007) and depressive symptoms (PHQ-9 9.29→5.38; p=.009), improved; however, DB remained within the clinical range. Glycaemic changes were modest (HbA1c −0.9%; TIR −3.1%). Conclusion: While improvements in several psychological outcomes were observed in both study arms, likely reflecting structured care, only CamAPS FX use was associated with reduction in burnout to non-clinical levels, improved well-being and quality of life, alongside significant enhancements in glycaemic management, demonstrating usefulness of HCL therapy in a high-risk population. Disclosure K. Cyranka: None. J. Hohendorff: Speaker's Bureau; Ended; Dexcom, Inc. Research Support; Current; Ypsomed AG. M.P. Wróbel: None. A. Grzelka-Wozniak: Other - Speaker; Ended; Novo Nordisk, Eli Lilly and Company, AstraZeneca, Roche Diabetes Care, Boehringer Ingelheim International GmbH. E. Sochacka-Tatara: None. M. Plonka-Stepien: None. B. Matejko: Speaker's Bureau; Ended; Abbott. Speaker's Bureau; Current; Medtronic. Speaker's Bureau; Ended; Dexcom, Inc., Ascensia Diabetes Care. M. Adamczyk-Hohendorff: None. D. Rokicka: None. D. Zozulinska-Ziólkiewicz: Advisory Panel; Current; Abbott Diabetes. Speaker's Bureau; Current; Abbott Diabetes, Eli Lilly and Company, Novo Nordisk, Sanofi, Dexcom, Inc. Advisory Panel; Current; Medtronic. Speaker's Bureau; Current; Medtronic, Servier Laboratories. M. Malecki: Consultant; Current; Abbott. Speaker's Bureau; Current; Dexcom, Inc. Research Support; Current; Ypsomed AG. Speaker's Bureau; Current; AstraZeneca, Boehringer Ingelheim International GmbH, Novo Nordisk A/S. Advisory Panel; Current; Lilly. Speaker's Bureau; Current; Sanofi. Research Support; Current; Medtronic. Speaker's Bureau; Current; Servier Laboratories. T. Klupa: Speaker's Bureau; Current; Abbott Diabetes, Eli Lilly and Company, Boehringer Ingelheim International GmbH, Dexcom, Inc., Novo Nordisk. Research Support; Current; Medtronic. Advisory Panel; Current; Sanofi. Speaker's Bureau; Current; KRKA, Servier Laboratories, AstraZeneca.