High glycemic variability is associated with worse Continuous Glucose Monitoring metrics in children and adolescents with type 1 diabetes

Objective: The primary aim of this study was to quantify the prevalence of children and adolescents with T1D who achieve the recommended target for CV identifying the determining factors to reach this target. The secondary aim was to examine the relationship between CV, the other metrics derived from CGM data and clinical parameters. Method: CGM data were collected from 805 children/adolescents with T1D. Several CGM metrics and patients' characteristics were evaluated. Participants were stratified by CV≤36% and CV>36%. Binary logistic regression analysis was run to identify the determining factors of high CV. Results CV was positively correlated with %TBR<70mg/dL, %TBR<54 mg/dL, %TAR>250 mg/dL, LBGI, HBGI and negatively with %TIR. CV≤36% was found in 31.4% of the subjects. The CV>36% group spent less time in %TIR, more time in hypoglycemia and hyperglycemia with lower proportion of subjects using rtCGM and CSII. Percentage of TBR<70mg/dL and TAR>250mg/dL were significant predictors of CV>36%, whereas age, gender, BMI, duration of diabetes, type of CGM device, type of insulin therapy administration and %TIR were not significant predictors (p<0.001,R2Nagelkerke=0.48). Conclusions: CV identifies children and adolescents with worse glycemic control at higher risk of both hypoglycemia and hyperglycemia.