Time in Range, Especially Overnight Time in Range, Is Associated With Sudomotor Dysfunction in Patients With Type 1 Diabetes

Abstract Background: To research the relationship between time in range (TIR) including overnight TIR and sudomotor function detected by SUDOSCAN in type 1 diabetes (T1D).Methods: 95 patients with T1D were enrolled. TIR of 3.9-10.0 mmol/L was evaluated with CGM. SUDOSCAN measured feet electrochemical skin conductance (FESC) and sudomotor dysfunction was defined as average FESC<60µS. Logistic regressions were applied to examine the independent association of TIR and overnight TIR with sudomotor function.Results: The overall prevalence of sudomotor dysfunction was 28.42%. Patients with sudomotor dysfunction had significantly lower TIR for the whole recorded phase and for nighttime. The sudomotor dysfunction prevalence progressively declined with the ascending tertiles of TIR and nocturnal TIR (P for trend <0.05). Correlation analysis showed that the relationship between nocturnal TIR and FESC was stronger than that between TIR and FESC with correlation coefficient was respectively 0.362 and 0.356 (P <0.001). Finally, logistic regression analysis indicated the independently negative relation between TIR and nocturnal TIR and sudomotor dysfunction (P <0.05), notably, more statistically significant results were obtained between nocturnal TIR and sudomotor dysfunction. Conclusions: TIR is negatively correlated with sudomotor dysfunction in T1D independent of HbA1c. Furthermore, decreased nocturnal TIR is more closely related to the impaired function of sudomotor nerves in sweat glands.