Continuous glucose monitoring defined time-in-range is associated with sudomotor dysfunction in type 2 diabetes.

Background: Time in range (TIR), as a novel metric for glycemic control, has robust relevance with diabetic complications. Diabetic peripheral neuropathy (DPN) is characterized by sudomotor dysfunction.

Objective: To explore the relationship between TIR obtained from continuous glucose monitoring (CGM) and sudomotor function detected by SUDOSCAN in subjects with type 2 diabetes.

Methods: The research enrolled 466 inpatients with type 2 diabetes. All subjects underwent 3-d CGM and SUDOSCAN. SUDOSCAN was assessed with electrochemical skin conductance in hands (HESC) and feet (FESC). Average feet ESC < 60 µS was defined as sudomotor dysfunction (+), otherwise it was sudomotor dysfunction (-). TIR refers to the percentage of time when blood glucose is between 3.9-10 mmol/L during 1 d period.

Results: Among the enrolled subjects, 135 (28.97%) presented with sudomotor dysfunction. Patients with sudomotor dysfunction (+) showed a decreased level of TIR (P < 0.001). Compared to the lowest tertile of TIR, the middle and the highest tertiles of TIR was associated with an obviously lower prevalence of sudomotor dysfunction (20.51% and 21.94% vs 44.52%) (P < 0.001). In addition, with the increase of TIR, HESC and FESC increased (P < 0.001). Regression analysis demonstrated that TIR was inversely and independently linked with the prevalence of sudomotor dysfunction after adjusting for confounding values (odds ratio = 0.979, 95%CI: 0.971-0.987, P < 0.001).

Conclusions: The tight glycemic control assessed by TIR is of vitally protective value for sudomotor dysfunction in type 2 diabetes mellitus.