Eighteen-month hybrid closed-loop use in very young children with type 1 diabetes: a single-arm multicenter trial
Objective We aimed to evaluate the longer-term safety and efficacy of hybrid closed‑loop therapy in very young children with type 1 diabetes (T1D). Research Design and Methods Following a 16-week multi-national, randomized crossover trial comparing hybrid closed-loop (CL) with sensor-augmented pump (SAP) therapy in 74 very young children aged 1-7 years with T1D, participants were invited to an extension phase using CL for a further 18 months. Outcomes were compared to the primary phase SAP period and primary phase CL period. Results After the primary study phase, 60 participants were eligible to enroll in the extension. Of these, 49 consented (mean±SD age 6.6±1.5 years) to continue use of CL for 18 months. Percentage time in range (TIR) 3.9‑10.0mmol/L was 8.4 percentage points (95% CI 6.7 to 10.1; p<0.001) higher, while HbA1c was 0.4% ([5.0mmol/mol], 95% CI 0.3 to 0.6 [3.7 to 6.2]; p<0.001) lower during the CL extension phase compared to primary phase SAP period. At 18 months mean HbA1c was 6.7±0.5% and TIR 70±7%, compared to 6.7±0.5% and 71±6% in the primary phase CL period. Time in hypoglycemia (<3.9mmol/L) was similar between CL extension phase and both primary phase SAP and CL periods (p=0.31 and p=0.70 respectively). There were two severe hypoglycemia events and one other serious adverse event during the extension phase. One unexpected serious adverse device effect occurred. Conclusions Use of the Cambridge hybrid closed-loop system led to sustained improvements in glycemic control lasting more than 18 months in very young children with T1D.