Normal Values of Sudomotor Function Assessed by Electrochemical Skin Conductance in the African Population

Background: Dysfunction of small nerve fibers remains a major public health problem. Subjects suspected of having small nerve fiber damage need to undergo reliable tests to confirm the diagnosis.Sudomotor function test is a reliable non-invasive exploration for detecting peripheral neuropathies.Nevertheless, the normal reference values derived from the sudomotor function test are not known in the African population. The objective of this study is therefore to describe the normal values of Electrochemical Skin Conductance (ESC) measured by the Sudomotor function test in healthy Africansubjects.Materials and methods: Between December 1st, 2021 and May 31,2022, 475 healthy subjects (median age: 42[31-53] years, 46% of men) had a measurement of ESC, using sudomotor function test in the hands and feet. Investigators proposed the examination and received participants' consent, demographic, anthropometric, biological and clinical data were obtained before the test.Results: ESC were statistically higher in men compered to women (right hand ESC:70 [60-78] vs. 63 [53-72], left hand ESC: 72 [61-80] vs. 68 [57-75], right foot ESC: 77 [82-99] vs. 72 [64-79], ESC left foot : 76 [68-82] vs. 72 [62-78] respectively. ESC were significantly inversely correlated with age (right hand ESC: r=-0.12, p=0.006; left hand ESC: r=-0.11, p=0.01; right foot ESC: r=-0.37, p