Longitudinal continuous glucose monitoring study in young children with pre-symptomatic type 1 diabetes followed in the Environmental Determinants of Islet Autoimmunity (ENDIA) at-risk cohort study

Objective To characterise longitudinal continuous glucose monitoring (CGM) data in young children with pre-symptomatic type 1 diabetes. Research Design and Methods Between 2021 and 2024, children in the Australian ENDIA study with persistent multiple islet autoimmunity underwent blinded CGM assessments every 3-6 months. CGM derived metrics (standard deviation sensor glucose (SDSGL), coefficient of variation (CV), mean sensor glucose (SGL) and percent time >7.8 mmol/L(140mg/dL)) were determined and are presented for each child by time from islet autoantibody detection. Results A total of 178 CGM assessments were analysed for 36 children, with a median age of 4.5[3.5,6.0] years at their first assessment, who underwent a median 5.5[2,7] assessments of 11[9,15] days duration each. High within-person variability was observed in serial CGM metrics, including %time>7.8mmol/L(140mg/dL) (intra-class correlation coefficient of 0.30). Conclusions Further research is needed to inform interpretation of CGM derived metrics in young children with pre-symptomatic type 1 diabetes.