Insulin resistance and CGM-derived parameters in people with type 1 diabetes: are they associated?

Abstract Background Insulin resistance (IR) is increasingly more prevalent in people with type 1 diabetes (T1D). Objective We investigated whether IR is associated with continuous glucose monitor (CGM)-derived parameters (glucometrics), such as time in range (TIR), time above range (TAR), time below range (TBR), and glycemic variability (CV). Methods This is a retrospective analysis of 2 databases: IR was quantified according to the estimated glucose disposal rate (eGDR) (NCT04664036) and by performing a hyperinsulinemic-euglycemic clamp (HEC) (NCT04623320). All glucometrics were calculated over 28 days. Results A total of 287 subjects were included. Mean age was 46 ± 17 years, 55% were male, TIR was 57% ± 14%, and eGDR was 7.6 (5.6-9.3) mg/kg/min. The tertile of people with the lowest eGDR (highest level of IR) had a higher TAR compared to the tertile with the highest eGDR (39% ± 15% vs 33% ± 14%, P = .043). Using logistic regression, a higher eGDR was associated with a higher chance to fall in a higher TIR-tertile (odds ratio [OR] 1.251, P < .001), a lower TAR-tertile (OR 1.281, P < .001), and a higher TBR-tertile (OR 0.893, P = .039), adjusted for age, sex, diabetes duration, smoking status, and alcohol intake. In the 48 people undergoing a HEC, no significant association between glucometrics and the HEC-determined glucose disposal rate (M-value) was observed. Conclusion In people with T1D, an association between IR, measured by eGDR, and worse CGM profiles was observed.