Hybrid Closed Loop in Adolescents and Young Adults Living with Type 1 Diabetes: A Real-World Study.

To evaluate the long-term metabolic outcomes and safety of hybrid closed loop (HCL) in youth living with type 1 diabetes, including people with very poor metabolic control, this observational, retrospective, monocentric study included 101 patients aged 15-25 years. After a mean (±standard deviation; range) follow-up of 16 (±6; 3-31) months, HbA1c decreased from 9.6% ± 2.3% (82 ± 25 mmol/mol) at baseline to 8.0% ± 1.4% (64 ± 15 mmol/mol) (P < 0.001). Continuous glucose monitoring parameters showed the same trend (P < 0.001): the glucose management indicator decreased from 8.8% to 7.9%, time in range increased from 39% to 57%, and time below range decreased from 3.0% to 1.6%. Ten patients discontinued HCL. There was no more severe hypoglycemia or diabetes ketoacidosis under HCL compared with the year before HCL initiation. Five cases of new onset and four cases of worsening retinopathy were reported. Youth with type 1 diabetes can improve metabolic control thanks to HCL without increasing complication risk. Vigilance is required for preexisting retinopathy monitoring.