Aaron I Vinik1, A Gordon Smith2, J Robinson Singleton2, Brian Callaghan3, Barry I Freedman4, Jaakko Tuomilehto5,6,7,8, Lyse Bordier9, Bernard Bauduceau9, Frederic Roche10,11. 1. 1 Strelitz Diabetes Center for Endocrine and Metabolic Disorders and Neuroendocrine Unit/Department of Medicine, Eastern Virginia Medical School , Norfolk, Virginia. 2. 2 Department of Neurology, University of Utah , Salt Lake City, Utah. 3. 3 Department of Neurology, University of Michigan , Ann Arbor, Michigan. 4. 4 Nephrology/Internal Medicine, Wake Forest School of Medicine , Winston-Salem, North Carolina. 5. 5 Chronic Disease Prevention Unit, National Institute for Health and Welfare , Helsinki, Finland . 6. 6 Centre for Vascular Prevention, Danube-University Krems , Krems, Austria . 7. 7 Diabetes Research Group, King Abdulaziz University , Jeddah, Saudi Arabia . 8. 8 EVIDEM CONSULTORES , Madrid, Spain . 9. 9 Endocrinology Service, Instruction-des-Armées-Bégin Hospital , Saint-Mandé, France . 10. 10 Clinical Physiology and Exercise Service, VISAS Centre, CHU Saint Etienne , Saint Etienne, France . 11. 11 EA SNA EPIS, Jean Monnet de Saint Etienne University, University of Lyon , Lyon, France .
Abstract
BACKGROUND: Sudomotor dysfunction is one of the earliest pathophysiologic abnormalities in diabetes. Sudoscan™ (Impeto Medical, Paris, France) was developed as a noninvasive, rapid, and quantitative assessment of sudomotor function and has been shown to be sensitive in the detection of neuropathy. This global collaborative analysis aimed to establish reference values in healthy subjects of different ethnic groups, age, and gender, to define factors potentially affecting results, and to provide standardization of the methodology. MATERIALS AND METHODS: Data from 1,350 generally healthy study participants who underwent sudomotor function testing were collected and analyzed. The relationship between age, height, weight, gender, glycemic and lipid profiles, ethnicity, and hand and foot electrochemical skin conductance (ESC) was assessed among subgroups of participants. RESULTS: Lower mean hands and feet ESC values were observed in African American, Indian, and Chinese subjects (P < 0.0001). No participant discomfort or safety concern was reported in 1,376 tests. No significant difference in ESC was observed between women and men at the hands (75 [57-87] vs. 76 [56-89] μS; P = 0.35) or feet (83.5 [71-90] vs. 82.5 [70-91] μS; P = 0.12). The coefficient of correlation between right and left side ESC was r = 0.96, P < 0.0001 for hands and r = 0.97, P < 0.0001 for feet. A significant but weak correlation was observed between ESC and age: for hands, r = -0.17, P < 0.0001; for feet, r = -0.19, P < 0.0001. CONCLUSIONS: A normative reference range was established in whites showing that there was no effect of sex or body mass index and a slight decrease in ESC with age. Ethnicity influenced ESC scores, but additional studies are necessary to validate this effect and determine its mechanism and impact on nerve function.
BACKGROUND: Sudomotor dysfunction is one of the earliest pathophysiologic abnormalities in diabetes. Sudoscan™ (Impeto Medical, Paris, France) was developed as a noninvasive, rapid, and quantitative assessment of sudomotor function and has been shown to be sensitive in the detection of neuropathy. This global collaborative analysis aimed to establish reference values in healthy subjects of different ethnic groups, age, and gender, to define factors potentially affecting results, and to provide standardization of the methodology. MATERIALS AND METHODS: Data from 1,350 generally healthy study participants who underwent sudomotor function testing were collected and analyzed. The relationship between age, height, weight, gender, glycemic and lipid profiles, ethnicity, and hand and foot electrochemical skin conductance (ESC) was assessed among subgroups of participants. RESULTS: Lower mean hands and feet ESC values were observed in African American, Indian, and Chinese subjects (P < 0.0001). No participant discomfort or safety concern was reported in 1,376 tests. No significant difference in ESC was observed between women and men at the hands (75 [57-87] vs. 76 [56-89] μS; P = 0.35) or feet (83.5 [71-90] vs. 82.5 [70-91] μS; P = 0.12). The coefficient of correlation between right and left side ESC was r = 0.96, P < 0.0001 for hands and r = 0.97, P < 0.0001 for feet. A significant but weak correlation was observed between ESC and age: for hands, r = -0.17, P < 0.0001; for feet, r = -0.19, P < 0.0001. CONCLUSIONS: A normative reference range was established in whites showing that there was no effect of sex or body mass index and a slight decrease in ESC with age. Ethnicity influenced ESC scores, but additional studies are necessary to validate this effect and determine its mechanism and impact on nerve function.