Demographic, clinical, management and outcome characteristics of 8,004 young children with type 1 diabetes

Objective: To compare demographic, clinical, and therapeutic characteristics of children with type 1 diabetes aged <6 years across three international registries: Diabetes Prospective Follow-up Registry (DPV, Europe), T1D Exchange Quality Improvement Network (T1DX-QI, USA) and Australasian Diabetes Data Network (ADDN, Australasia). Research Design and Methods: Analysis of 2019-2021 prospective registry data from 8,004 children were compared. Results: Mean±SD age at diabetes diagnosis was 3.2±1.4 (DPV, ADDN), and 3.7±1.8 years (T1DX-QI). Diabetes duration was 1.4±1.3 (DPV), 1.4±1.6 (T1DX-QI), and 1.5±1.3 years (ADDN). and BMI z scores were in the overweight range in 36.2% (DPV), 41.8% (T1DX-QI), and 50.0% (ADDN). and Mean±SD HbA1c varied between registries: DPV 7.3±0.9% (56±10mmol/mol, T1DX-QI 8.0±1.4% (64±16mmol/mol), ADDN 7.7±1.2% (61±13mmol/mol). Overall, 37.5% of children achieved target HbA1c of <7.0% (53mmol/mol); 43.6% in DPV, 25.5% in T1DX-QI and 27.5% in ADDN. Use of diabetes technologies varied between registries for use of insulin pump: DPV 86.6%, T1DX 46.6%, and ADDN 39.2%; and continuous glucose monitoring (CGM): DPV 85.1%, T1DX-QI 57.6%, and ADDN 70.5%. Use of hybrid closed loop (HCL) systems was uncommon (0.5% (ADDN) to 6.9% (DPV)). Conclusions: Across three major registries, over half of children aged <6 years did not achieve target HbA1c of <7.0% (53 mmol/mol). CGM was used by most participants, while insulin pump use varied across registries and HCL use was rare. The differences seen in glycemia and use of diabetes technologies between registries requires further investigation to determine potential contributing factors and areas to target to improve the care of this vulnerable group.