Abstract
This study presents a comprehensive analysis of electrochemical skin conductance (ESC) values collected from over 1.9 million measurements using Withings Body Scan and Body Comp scales. Aimed at establishing normative values for ESC, this research incorporates a large, global dataset to explore the influence of age, sex, and circadian and seasonal variations on sudomotor function. Our findings reveal that ESC values exhibit a small, gradual decline with age and are potentially slightly lower in women compared to men. Notably, we identified significant daily and annual patterns in ESC values, suggesting the influence of chronobiological factors. By employing both univariate and multivariate regression models, including an approach using sinusoidal variations, we refined our understanding of these patterns. The study underscores the importance of considering these variations in clinical and home monitoring of ESC, offering new insights into peripheral neuronal aging and the potential for ESC as a biomarker for sympathetic and parasympathetic nervous system balance. Our work establishes a crucial reference for interpreting ESC measurements, taking into account demographic, biological, and seasonal variations, and highlights the need for further research to explore the clinical implications of these findings.