Evaluation of sudomotor function in adult patients with long‑lasting type 1 diabetes

INTRODUCTION The function of the sweat glands appears to be impaired in patients with diabetic complications. OBJECTIVES The aim of the study was to evaluate sudomotor function in adult patients with type 1 diabetes (DM1) and healthy controls and its relationship with metabolic control and diabetic complications. PATIENTS AND METHODS The study group included 404 patients with DM1 (194 women), aged 41 years (interquartile range [IQR], 32-51 years) and with disease duration of 23 years (IQR, 18-31 years). The control group included 84 healthy volunteers. Electrochemical skin conductance (ESC) in the feet and hands was measured in both groups. RESULTS Patients with DM1 had lower ESC than controls (feet: 80 μS [IQR, 65-85 μS] vs 83 μS [IQR, 78.5-87 μS], P <0.001; hands: 63 μS (IQR, 51-75 μS) vs 69 μS (IQR, 61.5-78.5 μS), P <0.001). In the study group, there was a negative correlation between ESC and patients' age, duration of diabetes, waist‑to‑hip ratio, skin autofluorescence, vibration perception threshold, as well as hemoglobin A1c and triglyceride levels, and a positive correlation with estimated glomerular filtration rate. Microvascular complications were diagnosed in 73.3% of the patients. Patients with retinopathy, diabetic kidney disease, peripheral neuropathy, and cardiac autonomic neuropathy had lower ESC in the feet and hands compared with those without complications. In multivariate logistic regression models, ESC was associated with the presence of any microvascular complications independently of potential confounders. CONCLUSIONS Diabetic microangiopathy, and in particular neuropathy, is related with reduced sudomotor function in DM1. A longer duration of diabetes, worse metabolic control, and reduced renal function are associated with greater sudomotor dysfunction.