Relationship between β-cell function and sudomotor function in patients with type 2 diabetes mellitus

Abstract

Objective To evaluate the relationship between β-cell function and sudomotor function in patients with type 2 diabetes mellitus (T2DM). Methods A total of 385 patients with T2DM who were hospitalized in the Department of Endocrinology, General Hospital of Eastern Theater Command from March 2016 to May 2018 were enrolled. According to the hands and feet electrochemical skin conductance (HESC, FESC) assessed with SUDOSCAN, patients were divided into normal sudomotor function group (n=262) and sudomotor dysfunction group (n=123). Basal insulin secretion was assessed with homeostasis model assessment of β-cell (HOMA-β). Early-phase insulin secretion function was assessed with the ratio of 30 min increment in C-peptide levels to 30 min increment in glucose levels (ΔC-P30/ΔG30) and the ratio of 30 min increment in insulin levels to 30 min increment in glucose levels (ΔI30/ΔG30). Total β-cell function was assessed with ratio of area under the curve (AUC) of C-peptide to the AUC of glucose in 120 min (C-PAUC/GAUC) and ratio of the AUC of insulin to the AUC of glucose in 120 min (IAUC/GAUC). Results (1) Compared with those in the normal sudomotor function group, ΔC-P30/ΔG30 and ΔI30/ΔG30 in sudomotor dysfunction group were lower [0.19(0.08, 0.30) vs 0.30(0.19, 0.53) and 1.47(0.67, 3.28) vs 2.26(1.28, 4.65), respectively, Z=-5.495,-3.897, all P<0.05], and also C-PAUC/GAUC and IAUC/GAUC were much lower [0.07(0.04, 0.16) vs 0.12(0.06, 0.25) and 2.79(0.76, 6.35) vs 3.30(1.35, 8.32) respectively, Z=-3.894, -2.092, all P<0.05]. (2)Both ΔC-P30/ΔG30 and ΔI30/ΔG30 were positively correlated with HESC (r=0.306, 0.272, respectively, all P<0.05) and FESC (r=0.304, 0.233, respectively, all P<0.05). (3) Multiple linear stepwise regression analysis showed that ΔC-P30/ΔG30, diabetes duration, age, glycated hemoglobin and plasma uric acid were independent factors that impacted on the sudomotor function. Conclusions Early-phase insulin secretion dysfunction independently related with sudomotor dysfunction in T2DM patients. Evaluation of sudomotor function maybe necessary for screening diabetic peripheral neuropathy in patients with early-phase insulin secretion dysfunction. Key words: Diabetes mellitus, type 2; β-cell function; Diabetic peripheral neuropathy; Sudomotor function