Normative values for electrochemical skin conductance measurements for quantitative assessment of sudomotor function in healthy Indian adults

Abstract

Context:Electrochemical skin conductance (ESC) test is a widely accepted objective technique for quantitatively assessing sudomotor dysfunction, which is one of the earliest-detected neurophysiologic abnormalities in diabetic patients with distal symmetric polyneuropathy.Aims:This study aimed to provide normative data for ESC values among healthy Indian participants and assess the potential influence of age, sex, and body mass index (BMI) on ESC measurements.Settings and Design:A sample of 217 healthy participants aged 18–75 years were recruited and assessed for parameters including age, gender, BMI, and ESC measurements of the hands and feet.Statistical Analysis Used:The Shapiro–Wilk test was used to assess the normality of the data. Pearson's correlation was used to evaluate the association between age, gender, and BMI, and ESC measurements.Results:The mean age of the participants was 43.3 ± 13.2 years, and mean BMI was 26.0 ± 4.3 kg/m2. Mean ESC for the hands and feet was 68.9 ± 13.1 and 71 ± 12.9 micro-Siemens, respectively, and there was a significant correlation between values from the right and left hands and feet (r = 0.9, P < 0.0001). A significant correlation was also observed between ESC measurements of the hands and feet (r = 0.94, P < 0.0001). ESC values of both hands and feet declined with age. A weak but significant inverse correlation between ESC and age was observed for the hands (r = 0.02, P = 0.01) and for the feet (r = 0.12, P < 0.0001). There was no significant difference in hand or feet ESC measurement between male and female participants. No significant correlation was observed between BMI and ESC of hands or feet. Only age was identified as a significant determinant of ESC on multivariate logistic regression analysis.Conclusions:Normative values for Indians are lower than that reported for Caucasians.

Normal values of sudomotor function assessed by electrochemical skin conductance in African population

“…This is between other ethnicity Indeed, using skin biopsy intra-epidermal nerve fiber density (IENFD) test 9 , Lui Y. et al, find that Chinese healthy subjects had lower values than the Finnish population (62.87 ± 15.25 fibers/mm² vs. 114.617 ± 32.322 fibers/mm² ) 10 . Nevertheless, our values were in line with that found by Shivaprasad et al, performed in 2018 in an Indian healthy population (hands and feet 68.9 ± 13.1 and 71 ± 12.9 μS, respectively) 11 . These values are still lower than those observed by Vinik et al in the white population.…”

Chronobiological, age and sex effects on Electrochemical Skin Conductance: results from a large observational data set

“…We noted that ESC values appear to exhibit a small gradual linear decline with age, and generally, women's values were slightly lower than men's. The findings related to age and sex were in line with expectations, as corroborated by previous studies, but these were limited to daytime measurements when ESC values reach their peak 3,14,15 . We identified annual and daily periodic patterns 13 that are relatively novel discoveries, made possible through the integration of ESC technology at the consumer level 12 .…”

“…All the coefficients are significant, and the estimates and pvalue are given in Table 3 for each covariate. The estimate for age (-0.25) and sex (woman, -3.39) are coherent with what was already demonstrated in clinical trial validation [14][15][16][17] . The average value contained within the intercept for the January month and nightly values is 75.8, the month estimates increase in February , then go down until October, and increase again.…”

“…The small sex parameter (~ 0-3) is considered as non relevant for clinical applications and our last model integrating the daily and annual variations also tends to make this effect mostly null. The age parameter was estimated to -0.12 in clinical study, and here around -0.2 3,14,15,17 Although we probably did not filter out all the non-healthy users and we have no information about ethnicity, which is another important confounder of ESC normal values 14,15,17,18 , we can consider that the effect of age should be between -0.1 and -0.2 per year. Thus, the ESC value is reduced by 1 to 2 points per decade for each individual, which should not be neglected in the clinical monitoring of patients at advanced ages to determine the possible evolution of a peripheral neuropathy.…”

“…For the RMSE we obtained 342,55 [341. 28, 342.99] and for the model parameters we have : 𝜇 ~ 71 [70, 72], annual variations ~ 2 [0, 3] with a peak at the end of March corresponding to day 88 [80, 100], daily variations ~ 6 [3,8] with a peak at 14 [13,15] hour, age ~ -0.2 [-0.2, -0.15] and sex (male) ~ 0 [0,0].…”