Closed-Loop Insulin Delivery Systems for People with Type 1 Diabetes and Chronic Very Poor Metabolic Control: It Works and Is Safe!

To evaluate the percentage of patients with type 1 diabetes (T1D) and very poor metabolic control who would agree to be treated with a hybrid closed-loop (HCL) insulin delivery system, and to assess metabolic improvement and safety. In a single center, we identified all patients aged >18 years with hemoglobin A1c (HbA1c) >11% (97 mmol/mol) before HCL treatment. We collected metabolic control and safety data up to 1 year post-HCL in those who accepted HCL after it was proposed to them. We identified 65 patients eligible for the study, 32 (50%) already used, or accepted to start using HCL. Patients were aged 18-49 years; mean(+/- standard deviation) baseline HbA1c was 12.5(+/- 1.8)% (113 +/- 20 mmol/mol). After 1 year, 25 patients (78%) were still using HCL and their mean HbA1c decreased to 9.4(+/- 1.9)% (79 mmol/mol) (P < 0.001). The rate of acute metabolic events was similar during the year of follow-up to the rate in the 3 years before HCL initiation. HCL systems should be considered in patients with T1D and very poor metabolic control.