biostudies-literatureRoyston CNational Institute for Health Research (NIHR)1008-1013https://www.ebi.ac.uk/biostudies/studies/S-EPMC7618672biostudies-literatureUnknown27(12)Objective: To evaluate trends in insulin delivery and day-to-day variability of insulin requirements over 48 months of hybrid closed-loop use following diagnosis of type 1 diabetes (T1D) in individuals aged 10-16 years. Methods: A secondary analysis of the closed-loop arm of an open-label, multicenter, randomized, parallel hybrid closed-loop trial assessing closed-loop insulin delivery in newly diagnosed children and adolescents with T1D was conducted. Mean total daily dose (TDD) over 24 h and during the night, as well as mean total basal and bolus insulin over 24 h, were calculated. Day-to-day variability of insulin requirements was evaluated over 24 h and at night. Results: TDD increased from 27.2 ± 16.1 units/d (mean ± standard deviation) at 0-3 months following diagnosis to 65.7 ± 24.9 units/d at 42-48 months. The proportion of total daily insulin delivered as basal insulin rose from 41% to 61% over 48 months. Day-to-day variability of insulin requirements after diagnosis was high (coefficient of variation at 0-3 months: 23.3 ± 0.9%) and remained stable over 48 months. No clinically relevant sex-based differences were observed in insulin requirements. Conclusions: During the first 48 months after diagnosis of T1D, insulin requirements in children and adolescents more than double with hybrid closed-loop insulin delivery. Over time, a greater proportion of insulin is administered via the closed-loop algorithm, and the high day-to-day variability in insulin needs underscores the importance of initiating adaptive closed-loop systems from diagnosis.Diabetes technology & therapeuticsTrends in Total Daily Dose and Variability of Insulin Requirements in Newly Diagnosed Children and Adolescents with Type 1 Diabetes over 48 Months.PMC761867214/23/09Hartnell SAllen JMWilinska MERandell TWare JBoughton CKRoyston CGhatak ACLOuD ConsortiumBesser REJCampbell FMElleri DHovorka RThankamony ATrevelyan NfalseTrends in Total Daily Dose and Variability of Insulin Requirements in Newly Diagnosed Children and Adolescents with Type 1 Diabetes over 48 Months.Objective: To evaluate trends in insulin delivery and day-to-day variability of insulin requirements over 48 months of hybrid closed-loop use following diagnosis of type 1 diabetes (T1D) in individuals aged 10-16 years. Methods: A secondary analysis of the closed-loop arm of an open-label, multicenter, randomized, parallel hybrid closed-loop trial assessing closed-loop insulin delivery in newly diagnosed children and adolescents with T1D was conducted. Mean total daily dose (TDD) over 24 h and during the night, as well as mean total basal and bolus insulin over 24 h, were calculated. Day-to-day variability of insulin requirements was evaluated over 24 h and at night. Results: TDD increased from 27.2 ± 16.1 units/d (mean ± standard deviation) at 0-3 months following diagnosis to 65.7 ± 24.9 units/d at 42-48 months. The proportion of total daily insulin delivered as basal insulin rose from 41% to 61% over 48 months. Day-to-day variability of insulin requirements after diagnosis was high (coefficient of variation at 0-3 months: 23.3 ± 0.9%) and remained stable over 48 months. No clinically relevant sex-based differences were observed in insulin requirements. Conclusions: During the first 48 months after diagnosis of T1D, insulin requirements in children and adolescents more than double with hybrid closed-loop insulin delivery. Over time, a greater proportion of insulin is administered via the closed-loop algorithm, and the high day-to-day variability in insulin needs underscores the importance of initiating adaptive closed-loop systems from diagnosis.2025-01-01T00:00:00Z2025 Dec2026-06-14T05:44:41.922Z2026-06-14T03:09:17.838ZS-EPMC76186724080360710.1177/15209156251369882