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

BACKGROUND: Dysfunction of small nerve fibers remains a major public health concern. Subjects suspected of having small nerve fiber damage need to undergo reliable tests to confirm the diagnosis. Sudomotor function test is a reliable noninvasive 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 was therefore to describe the normal values of Electrochemical Skin Conductance (ESC) measured by the sudomotor function test in healthy African subjects. MATERIALS AND METHODS: Between December 1st, 2021 and May 31st, 2022, ESC was measured in 475 healthy subjects (median age: 42 [31-53] years, 46% men) using a 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. Data on 475 healthy study participants who underwent sudomotor function testing was collected and analyzed. The sociodemographic (age, sex), anthropometric (weight, height, waist circumference, body mass index), diastolic blood pressure, systolic blood pressure, heart rate, and electrochemical skin conductances of the hands and feet were assessed. RESULTS: ESC values were statistically higher in men compared to women (right hand ESC: 70 [60-78] versus 63 [53-72], left hand ESC: 72 [61-80] versus 68 [57-75], right foot ESC: 77 [82-99] versus 72 [64-79], ESC left foot: 76 [68-82] versus 72 [62-78] respectively). ESC values 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<0.0001; ESC left foot: r=-0.38, P<0.0001). ESC values measured in feet were significantly inversely correlated with body mass index (right foot r=-0.22, P<0.0001; left foot r=-0.21, P<0.0001). CONCLUSION: This study reports normal reference values for ESCs according to age and gender in the healthy African population. Progressive decrease in ESC with aging is confirmed by our data. The value of ESC seems lower in the African population than in other reported ethnicities. This finding needs to be further explored in additional studies.

The Relationship between the Ewing Test, Sudoscan Cardiovascular Autonomic Neuropathy Score and Cardiovascular Risk Score Calculated with SCORE2-Diabetes.

Background and Objectives: Cardiac autonomic neuropathy (CAN) is a severe complication of diabetes mellitus (DM) strongly linked to a nearly five-fold higher risk of cardiovascular mortality. Patients with Type 2 Diabetes Mellitus (T2DM) are a significant cohort in which these assessments have particular relevance to the increased cardiovascular risk inherent in the condition. Materials and Methods: This study aimed to explore the subtle correlation between the Ewing test, Sudoscan-cardiovascular autonomic neuropathy score, and cardiovascular risk calculated using SCORE 2 Diabetes in individuals with T2DM. The methodology involved detailed assessments including Sudoscan tests to evaluate sudomotor function and various cardiovascular reflex tests (CART). The cohort consisted of 211 patients diagnosed with T2DM with overweight or obesity without established ASCVD, aged between 40 to 69 years. Results: The prevalence of CAN in our group was 67.2%. In the study group, according SCORE2-Diabetes, four patients (1.9%) were classified with moderate cardiovascular risk, thirty-five (16.6%) with high risk, and one hundred seventy-two (81.5%) with very high cardiovascular risk. Conclusions: On multiple linear regression, the SCORE2-Diabetes algorithm remained significantly associated with Sudoscan CAN-score and Sudoscan Nephro-score and Ewing test score. Testing for the diagnosis of CAN in very high-risk patients should be performed because approximately 70% of them associate CAN. Increased cardiovascular risk is associated with sudomotor damage and that Sudoscan is an effective and non-invasive measure of identifying such risk.

Association of electrochemical skin conductance with neuropathy in chemotherapy-treated patients.

PURPOSE: Chemotherapy-induced peripheral neuropathy (CIPN) is an adverse event of cancer treatment that can affect sensory, motor, or autonomic nerves. Assessment of autonomic neuropathy is challenging, with limited available tools. Accordingly, it is not routinely assessed in chemotherapy-treated patients. In this study, we aimed to examine whether electrochemical skin conductance (ESC) via Sudoscan, a potential measure of autonomic function, associates with subjective and objective measures of CIPN severity and autonomic neuropathy. METHODS: A cross-sectional assessment of patients who completed neurotoxic chemotherapy 3-24 months prior was undertaken using CIPN patient-reported outcomes (EORTC-QLQ-CIPN20), clinically graded scale (NCI-CTCAE), neurological examination score (TNSc), autonomic outcome measure (SAS), and Sudoscan. Differences in CIPN severity between participants with or without ESC dysfunction were investigated. Linear regression analyses were used to identify whether ESC values could predict CIPN severity. RESULTS: A total of 130 participants were assessed, with 93 participants classified with CIPN according to the clinically graded scale (NCI-CTCAE/grade ≥ 1), while 49% demonstrated hands or feet ESC dysfunction (n = 46). Participants with ESC dysfunction did not significantly differ from those with no dysfunction on multiple CIPN severity measures (clinical-grade, patient-report, neurological examination), and no differences on the autonomic outcome measure (SAS) (all p > 0.0063). Linear regression analyses showed that CIPN could not be predicted by ESC values. CONCLUSIONS: The inability of ESC values via Sudoscan to predict clinically-graded and patient-reported CIPN or autonomic dysfunction questions its clinical utility for chemotherapy-treated patients. The understanding of autonomic neuropathy with chemotherapy treatment remains limited and must be addressed to improve quality of life in cancer survivors.

Sudomotor dysfunction in patients with gluten neuropathy.

BACKGROUND AND AIM: Gluten neuropathy (GN) is a common neurological manifestation of gluten sensitivity (GS), characterized by serological evidence of GS, while other risk factors for developing neuropathy are absent. The degree of small fiber dysfunction in GN has not been studied in depth to date. Small fiber involvement may lead to pain, thermal perception abnormalities, and sweat gland dysfunction. Sudomotor innervation refers to the cholinergic innervation of the sympathetic nervous system through small fibers in the sweat glands. The aim of our study was to assess the sudomotor function of GN patients. METHODS: Patients with GN were recruited. Clinical and neurophysiological data were obtained. HLA-DQ genotyping was performed. The skin electrochemical conductance (ESC) was measured with SUDOSCANTM. RESULTS: Thirty-two patients (25 males, mean age 69.5±10.2 years) were recruited. Thirteen patients (40.6%) had abnormal sudomotor function of the hands. Sixteen patients (50%) had abnormal sudomotor function of the feet. Twenty-one patients (65.6%) had abnormal sudomotor function of either the hands or feet. Sudomotor dysfunction did not correlate with the type of neuropathy (length-dependent neuropathy or sensory ganglionopathy), gluten-free diet adherence, severity of neuropathy, and duration of disease or HLA-DQ genotype. No differences in the ESC were found between patients with painful and patients with painless GN. CONCLUSION: Sudomotor dysfunction affects two-thirds of patients with GN. The lack of correlation between pain and sudomotor dysfunction suggests different patterns of small fiber involvement in patients with GN.

SUDOSCAN, an Innovative, Simple and Non-Invasive Medical Device for Assessing Sudomotor Function.

Diabetic autonomic neuropathy is probably the most undiagnosed but serious complication of diabetes. The main objectives were to assess the prevalence of peripheral and autonomic neuropathy in a population of diabetic patients, analyze it in a real-life outpatient unit scenario and determine the feasibility of performing SUDOSCAN tests together with widely used tests for neuropathy. A total of 33 patients were included in the study. Different scoring systems (the Toronto Clinical Neuropathy Score-TCNS; the Neuropathy Disability Score-NDS; and the Neuropathy Symptom Score-NSS) were applied to record diabetic neuropathy (DN), while the SUDOSCAN medical device was used to assess sudomotor function, detect diabetic autonomic neuropathy and screen for cardiac autonomic neuropathy (CAN). Fifteen (45.5%) patients had sudomotor dysfunction. The SUDOSCAN CAN risk score was positively correlated with the hands' electrochemical sweat conductance (ESC), diastolic blood pressure (DBP), the level of the glycated hemoglobin, as well as with the TCNS, NDS and NSS. Performing SUDOSCAN tests together with other tests for DN proved to be a feasible approach that could be used in daily clinical practice in order to screen for DN, as well as for the early screening of CAN, before more complex and time-consuming tests.

Electrochemical skin conductance by Sudoscan®: a new tool to predict intradialytic hypotension.

BACKGROUND: Intradialytic hypotension (IDH), a common complication in haemodialysis (HD) patients, is associated with multiple risk factors including cardiac dysfunction and alterations of the peripheral autonomic nervous system. To what extent dysautonomia may contribute to the occurrence of IDH remains elusive. We sought to investigate the clinical utility of Sudocan®, a device that quantifies dysautonomia, in the prediction of IDH. METHODS: We conducted a prospective monocentric study in adult HD patients from July 2019 to February 2020. Dysautonomia was assessed by the measurements of hand and foot electrochemical skin conductance (ESC) using Sudocan®, before HD. The primary endpoint was the incidence of IDH (The National Kidney Foundation/Kidney-Dialysis Outcome Quality Initiative definition), according to the presence of a pathological hand and/or foot ESC value, during the 3-month study period. RESULTS: A total of 176 HD patients (64 ± 14 years old) were enrolled. Mean pre-dialysis HD hand and foot ESC was 45 ± 20 and 54 ± 22 µS, respectively. About 35% and 40% of patients had a pathological ESC at the hand and foot, respectively. IDH occurred in 46 patients. Logistic regression showed that pathologic pre-dialysis HD hand ESC was associated with an increased risk of IDH [odds ratio = 2.56, 95% CI (1.04-6.67), P = 0.04]. The cumulative risk incidence of IHD during the study was 5.65 [95% CI (2.04-15.71), P = 0.001] and 3.71 [95% CI (1.41-9.76), P = 0.008], with a pathological hand and foot ESC, respectively. CONCLUSIONS: A pathological hand ESC, as assessed by a non-invasive Sudoscan® test, is associated with an increased risk of IDH.

Efficacy and tolerability of DPP4 inhibitor, teneligliptin, on autonomic and peripheral neuropathy in type 2 diabetes: an open label, pilot study.

BACKGROUND: Diabetic neuropathy increases risk of cardiovascular disease, peripheral artery disease, foot amputation and overall mortality. Not only hyperglycaemia induced nerve damage is harder to repair using currently approved medications, but also, the use of these agents is often limited by the extent of pain relief provided and side effects. METHODOLOGY: In this prospective, open-label, pilot study, 20 type-2 diabetes mellitus patients (male/female=13/7, mean age- 56.1±8.04 years), meeting inclusion/exclusion criteria, were treated with dipeptidyl peptidase-4 (DPP-4) inhibitor, Teneligliptin, 20mg once a day for three months. Efficacy parameters: Sudomotor function (Sudoscan score); parasympathetic dysfunction assessed using Ewing's criteria i.e. heart rate response to -standing (HRS), -valsalva (HRV) and -deep breath (HRD); sympathetic dysfunction assessed as blood pressure response to -standing (BPS) and -handgrip (BPH); ankle brachial index (ABI), vibration perception threshold (VPT), C-reactive protein, glycemic profile and health related quality of life (HRQoL); and, tolerability parameters: complete blood count, liver function tests, serum creatinine, thyroid stimulating hormone, QT- interval and serum vitamin B12 levels, were measured. RESULTS: There was no statistical difference in BMI, SBP, DBP, HRD, BPH and all safety parameters. After 12 weeks treatment, there was improvement in HRS (p<0.01) and HRV (p<0.01), but not in HRD (p=0.12). BPS was significantly lowered (p <0.01), but not the BPH (p =0.06). Sudoscan score was increased, while VPT was significantly decreased (both p<0.01). CONCLUSION: Teneligliptin not only improves the glycemic status but also improves sudomotor function, peripheral and autonomic neuropathy, and reduces vascular inflammation in type 2 diabetes.

Electrochemical Skin Conductance and Quantitative Sensory Testing on Fibromyalgia.

BACKGROUND: An impairment of the peripheral nervous system has been suggested in fibromyalgia (FM). Noninvasive distal electrochemical skin conductance (ESC) has been studied little so far when combined with quantitative sensory testing (QST) in patients with FM. METHODS: This study (clinicaltrials.gov NCT03347669) included 50 female patients with FM and 50 matched healthy volunteers (HVs). ESC (measured in microsiemens [µS] with Sudoscan), as well as psychological, quality of life, sleep, and social characteristics, were assessed in both groups. In a subgroup of 24 patients with FM and 24 HVs, QST of cold and warm detection and pain thresholds and diffuse noxious inhibitory controls (DNICs) were explored. Statistical analysis was performed for a 2-sided type I error at 5%. RESULTS: Between patients with FM and HVs, ESC values differed (71.4 ± 11.2 µS vs. 74.4 ± 10.3 µS, respectively; P = 0.003), especially on the dominant hand (P = 0.03), where more patients with FM had ESC values < 66 µS than did HVs (P = 0.046). No difference was observed on feet. In patients with FM, all collected characteristics were impaired (P < 0.001), DNICs were less functional, detection thresholds occurred later, and pain thresholds occurred earlier. No correlation was observed between ESC and DNICs or with any parameter. CONCLUSION: This study shows that the sudomotor function is significantly impaired in patients with FM, especially on the dominant hand. This occurs in parallel with adjustments of detection and pain thresholds in the context of deficient spinal pain modulation. ESC values combined with QST values are relevant in the context of patients with FM and need to be explored further in this nociception-autonomic system intertwining.

Assessment of autonomic innervation of the foot in familial amyloid polyneuropathy.

BACKGROUND AND PURPOSE: Distal involvement of autonomic nerve fibers is critical in familial amyloid polyneuropathy (FAP) due to transthyretin (TTR) mutation. This study compares different methods for assessing autonomic foot innervation in TTR-FAP patients. METHODS: Three groups of seven TTR-FAP patients were included, according to disease severity: clinically asymptomatic, moderate or advanced neuropathy. The autonomic investigation included the eutectic mixture of local anesthetics test and laser Doppler flowmetry for vasomotor aspects and the Sudoscan® (measuring electrochemical skin conductance) and Neuropad® test for sudomotor aspects. Somatic innervation was assessed by performing nerve conduction studies, quantitative sensory testing [including vibration, cold and warm detection threshold (WDT) measurements] and laser evoked potentials. RESULTS: The results of all neurophysiological tests varied according to TTR-FAP severity (P ≤ 0.01, Kruskal-Wallis test), except for the eutectic mixture of local anesthetics test and laser Doppler flowmetry variables. In addition, the sudomotor tests (Sudoscan or Neuropad) or WDT measurement provided early markers of neuropathy in two of the seven asymptomatic carriers. Finally, all neurophysiological results correlated with the Neuropathy Impairment Score (r values between -0.88 and -0.66, P < 0.005, Spearman test), except the cold detection threshold. CONCLUSIONS: The Neuropad test could be used to detect TTR-FAP onset, but confirmation requires electrochemical skin conductance and WDT measurement. The Sudoscan technique, but not the Neuropad test (at least assessed at a fixed time point), could be valuable to follow the progression of the neuropathy. Follow-up investigation should also include large-fiber investigation (e.g. nerve conduction studies and vibration detection threshold). Conversely, reliable tests for assessing vasomotor disturbances in limb extremities of TTR-FAP patients are still awaited.

Electrochemical skin conductance: a systematic review.

PURPOSE: Currently available techniques for the evaluation of small fiber neuropathy and related sudomotor function remain suboptimal. Electrochemical skin conductance (ESC) has recently been introduced as a simple noninvasive and fast method for the detection of sudomotor dysfunction. The purpose of this review is to synthesize and appraise research using ESC measurements for sudomotor evaluation in adults. METHODS: Electronic databases including MEDLINE and Google Scholar were searched (up to March 13, 2017). The search strategy included the following terms: "electrochemical skin conductance," "Sudoscan," and "EZSCAN." Evidence was graded according to defined quality indicators including (1) level of evidence; (2) use of established tests as reference tests (e.g., quantitative sudomotor axon test [QSART], sympathetic skin responses [SSR], thermoregulatory sweat test [TST], and skin biopsies to assess sudomotor and epidermal small fibers); (3) use of consecutive/non-consecutive subjects; and (4) study design (prospective/retrospective). RESULTS: A total of 24 studies met the inclusion criteria. These were classified into preclinical, normative, comparative/diagnostic, or interventional. ESC measurement properties, diagnostic accuracy, and similarities to and differences from established tests were examined. CONCLUSIONS: ESC measurements expand the arsenal of available tests for the evaluation of sudomotor dysfunction. The advantages and disadvantages of ESC versus established tests for evaluating sudomotor/small fiber function reviewed herein should be used as evidence to inform future guidelines on the assessment of sudomotor function.

Sudomotor function testing by electrochemical skin conductance: does it really measure sudomotor function?

OBJECTIVE: Electrochemical skin conductance (ESC) is a non-invasive test of sweat function developed as a potential marker of small fiber neuropathy. Here we systematically review the evolution of this device and the data obtained from studies of ESC across different diseases. METHODS: Electronic databases, including MEDLINE, and Google Scholar were searched through to February 2018. The search strategy included the following terms: "electrochemical skin conductance," "EZSCAN," and "Sudoscan." The data values provided by each paper were extracted, where available, and input into tabular and figure data for direct comparison. RESULTS: Thirty-seven studies were included this systematic review. ESC did not change by age or gender, and there was significant variability in ESC values between diseases, some of which exceeded control values. Longitudinal studies of disease demonstrated changes in ESC that were not biologically plausible. Of the 37 studies assessed, 25 received support from the device manufacturer. The extracted data did not agree with other published normative values. Prior studies do not support claims that ESC is a measure of small fiber sensory function or autonomic function. CONCLUSIONS: Although many papers report significant differences in ESC values between disease and control subjects, the compiled data assessed in this review raises questions about the technique. Many of the published results violate biologic plausibility. A single funding source with a vested interest in the study outcomes has supported most of the studies. Normative values are inconsistent across publications, and large combined data sets do not support a high sensitivity and specificity. Finally, there is insufficient evidence supporting the claim that Sudoscan tests sudomotor or sensory nerve fiber function.

[The clinical value of SUDOSCAN in diagnosis of diabetic distal symmetrical peripheral neuropathy].

Objective: To evaluate the clinical value of SUDOSCAN in diagnosis of diabetic distal symmetrical peripheral neuropathy. Methods: According to the diagnostic criteria for multiple diabetic distal symmetrical peripheral neuropathy, a total of 130 patients with type 2 diabetes mellitus (T2DM) in Department of Endocrinology, the Affiliated Hospital of Qingdao University between August 2015 and July 2016 were divided into two groups, diabetic peripheral neuropathy group (DPN group, 50 cases) and non-diabetic peripheral neuropathy group (NDPN group, 80 cases). Additional 80 healthy volunteers were selected as healthy control group (NC group). SUDOSCAN was employed to detect electrochemical skin conductance (ESC, the unit was µS) of subjects' hands and feet, and the correlation between sensory nerve conduction velocity (SCV) and ESC was analyzed as well. Results: The average hands ESC in NC and T2DM group were (79.1±10.4) µS and (59.7±18.1) µS, respectively; the average feet ESC were (82.0±8.2) µS and (62.1±21.8) µS, respectively (both P<0.01). The average hands ESC in DPN and NDPN group were (53.2±18.9) µS and (63.7±16.5) µS; the average feet ESC were (53.5±24.4) µS and (67.4±18.2) µS, respectively (both P<0.05). The hands and feet ESC were positively correlated with SCV, and the correlation coefficient were 0.425 and 0.445, respectively (both P<0.01). The area under the receiver operating characteristic curve (ROC) of hands and feet ESC to evaluate diabetic symmetrical peripheral polyneuropathy were 0.785 and 0.768 (both P<0.01). Conclusion: SUDOSCAN is a promising tool for the diagnosis of diabetic symmetrical peripheral polyneuropathy.

Association of sudomotor dysfunction with risk of diabetic retinopathy in patients with type 2 diabetes.

PURPOSE: Sudomotor dysfunction is considered as one of the earliest manifestations of diabetic peripheral neuropathy. We aimed to investigate the association between sudomotor dysfunction non-invasively detected by the SUDOSCAN device and diabetic retinopathy (DR) in patients with type 2 diabetes. METHODS: A total of 2010 patients admitted to a tertiary hospital located in Shanghai were included from March 2020 to September 2023. Sudomotor function was assessed by the SUDOSCAN device, and sudomotor dysfunction was defined as feet electrochemical skin conductance (FESC) <60 µs. Fundus radiography was used for DR assessment, which was graded according to the severity, specifically: (1) non-DR; (2) mild nonproliferative DR (NPDR); (3) moderate NPDR/vision-threatening DR (VTDR). RESULTS: Among the enrolled 2010 patients, 525 patients had sudomotor dysfunction; 648 were diagnosed with DR, which was equivalent to 32.2% of all patients. Patients with sudomotor dysfunction had a significantly higher prevalence of DR, compared to those with normal sudomotor function (40.8% vs. 29.2%, P < 0.05). After controlling for confounding factors including HbA1c, sudomotor dysfunction was significantly associated with any DR (odd ratio [OR] = 1.57, 95% CI 1.26-1.96). When FESC was considered as a continuous variable, the multivariable-adjusted OR of DR was 1.29 (95% CI 1.17-1.42) for per 1-SD decrease in FESC. Furthermore, multinomial logistic regression revealed significant associations between sudomotor dysfunction and all stages of DR (mild NPDR: OR = 1.40, 95% CI 1.11-1.78; moderate NPDR/VTDR: OR = 2.35, 95% CI 1.60-3.46). CONCLUSIONS: Sudomotor dysfunction was significantly associated with DR in patients with type 2 diabetes.

The Importance of Evaluating Sudomotor Function in the Diagnosis of Cardiac Autonomic Neuropathy.

INTRODUCTION:  Cardiac autonomic neuropathy (CAN) is a disorder affecting the autonomic nerves that regulate the cardiovascular system, leading to irregular heart rate and blood pressure control. It is commonly associated with diabetes mellitus but can also result from other conditions such as autoimmune disorders, chronic kidney disease, alcohol abuse, and certain medications. Screening for CAN is essential, particularly in individuals with poor glycemic control, cardiovascular risk factors, or complications. Early identification of CAN is vital for timely intervention to prevent or manage cardiovascular complications effectively. Regular screening helps detect CAN before symptoms emerge, enabling early intervention to slow or halt its progression. This study examined the relationship between sudomotor function and cardiovascular reflex tests. MATERIAL AND METHODS:  This was a cross-sectional study conducted between June 2019 and June 2020. The study included 271 subjects aged 18 years and above who provided informed consent, were diagnosed with type 2 diabetes mellitus (T2DM), and were overweight or obese. Exclusion criteria encompassed patients with other types of diabetes, pregnant women, those with recent neoplasm diagnoses, stroke sequelae, history of myocardial infarction, or pelvic limb amputations. The assessment of cardiac autonomic neuropathy involved conducting an electrocardiogram and evaluating the QTc interval in the morning before taking medication. Additionally, cardiovascular reflex tests (CART) were conducted, including assessments of heart rate variability during deep breathing, the Valsalva maneuver, and changes in orthostatic position. Simultaneously, the diagnosis of CAN was assessed by performing a sweat test using a Sudoscan assessment (Impeto Medical, Moulineaux, France).  Results: More than half of the participants (52%, n=143) were female. Significant differences in statistical measures were noted between females and males regarding age, systolic blood pressure, fasting blood glucose, A1c level, total cholesterol, triglycerides, gamma-glutamyl transferase, and bilirubin levels. Within the CAN-diagnosed group (CAN+), 40.92% were classified as mild cases (n=90), 47.27% as moderate cases (n=104), and 11.81% as severe cases (n=26). Among the CAN+ group, 54% (n=119) were women. Electrochemical skin conductance was lower in the CAN+ group than the CAN- group in hands (67.34±15.51 µS versus 72.38±12.12 µS, p=0.008) and feet (73.37±13.38 µS versus 82.84 ±10.29 µS, p<0.001). The Sudoscan-CAN score significantly correlated with Ewing scores (r= 0.522, p<0.001). In multiple linear regression analysis, the Sudoscan-CAN score remained significantly associated with age, high BMI, long-standing diabetes, and Ewing score. CONCLUSIONS:  Sudoscan demonstrates potential in identifying patients with an increased risk of CAN. Its integration into clinical practice can improve patient outcomes through early detection, risk stratification, and personalized treatment approaches. Its non-invasive, portable, and user-friendly features render it suitable for utilization in outreach programs or resource-constrained settings as part of screening efforts designed to pinpoint high-risk individuals for additional assessment.

Sudoscan's Effectiveness in Identifying Chronic Kidney Disease in Patients With Type 2 Diabetes.

Chronic kidney disease (CKD) represents a significant public health issue, particularly prevalent among patients with type 2 diabetes mellitus (T2DM). CKD occurs in approximately 20% to 40% of adults with diabetes mellitus. Sudoscan potentially detects CKD early, providing a non-invasive and convenient alternative to traditional screening methods that rely on serum creatinine and urine albumin levels. This research involves 271 patients from a single medical center over one year, with all participants providing informed consent. The prevalence of CKD in our group was 26.5% (n = 72). This study integrates a comprehensive examination, including anthropometric measurements, biochemical profiles, and Sudoscan's electrochemical skin conductance testing. CKD diagnosis was confirmed via estimated glomerular filtration rate (eGFR) and albumin-to-creatinine ratio (ACR). The aim of this study was to explore the utility of Sudoscan in detecting CKD among patients with T2DM. Statistical analysis reveals moderate correlations between Sudoscan scores and traditional CKD markers like eGFR and albuminuria. It is beneficial in settings where conventional testing is less accessible, suggesting potential for broader CKD screening programs. Key findings suggest that Sudoscan can identify early renal dysfunction with reasonable sensitivity and specificity. Integrating Sudoscan in regular CKD screening could enhance early detection, allowing for timely interventions to prevent progression to end-stage renal disease and reduce healthcare burdens associated with advanced CKD. The results contribute to the ongoing assessment of innovative technologies in managing chronic diseases related to diabetes.

Predictive value of heart rate variability and electrochemical skin conductance measurements for cardiovascular autonomic neuropathy persistence in type 2 diabetes and prediabetes: A 3-year follow-up study.

OBJECTIVE: The study aimed to explore risk stratification approaches for cardiovascular autonomic neuropathy (CAN) in individuals with prediabetes and type 2 diabetes (T2DM) over a three-year follow-up period. METHODS: Participants underwent evaluations of autonomic function encompassing cardiovascular autonomic reflex tests (CARTs), baroreflex sensitivity (BRS), heart rate variability (HRV) in time domains (standard deviation of all normal RR intervals (SDNN)) and frequency domains (high frequency/low frequency ratio), and electrochemical skin conductance (ESC). The diagnosis of CAN relied on abnormal CART results. Subjects were categorized into 4 groups, based on their assessment of cardiac autonomic function at 3-year follow-up, relative to the presence or absence of CAN at baseline assessment: Persistent absence of CAN; Resolution of CAN; Progression to CAN; and Persistent CAN. RESULTS: Participants with T2DM/prediabetes (n = 91/7) were categorized as: Persistent absence of CAN (n = 25), Resolution of CAN (n = 10), Progression to CAN (n = 18), and Persistent CAN (n = 45) groups. The Persistent absence of CAN group showed significant associations with SDNN. The Resolution of CAN group exhibited notable associations with mean HbA1C (follow-up), while the Progression to CAN group displayed a significant link with baseline estimated glomerular filtration rate. The Persistent CAN group demonstrated significant associations with SDNN and Sudoscan CAN risk score. Screening recommendations involve biennial to annual assessments based on risk levels, aiding in CAN detection and subsequent comprehensive and time-intensive autonomic function tests for confirmation. The study's findings offer improved risk categorization approaches for detecting CAN, which has relevance for shaping public health strategies.

Sympathetic and electrochemical skin responses in the assessment of sudomotor function: a comparative study.

OBJECTIVES: The sympathetic skin response (SSR) is a well-established test, whereas the electrochemical skin conductance (ESC) is still under evaluation. Our aim was therefore to assess the diagnostic accuracy of ESC to detect abnormal sudomotor function, using SSR as a reference test. METHODS: A cross sectional observational study was performed of 61 neurological patients assessed for possible sudomotor dysfunction and 50 age-matched healthy controls (HC). Patients with diagnoses of vasovagal syncope (VVS, n=25), Parkinson's disease (PD, n=15), multiple system atrophy (MSA, n=11) and peripheral neuropathies (PN, n=10) were included. Sudomotor function was assessed with SSR and ESC tests in all participants. The absence of SSR in the palms or soles indicates abnormal sudomotor function. Receiver operating characteristic (ROC) analysis was used to assess the diagnostic value of the ESC. Cardiovascular autonomic (CV-Aut) function was evaluated through the Ewing score, based on the following tests: Heart rate change with deep breathing, Valsalva ratio, 30:15 ratio, blood pressure changes on standing and during isometric exercise. A Ewing score ≥ 2 indicates the presence of CV-Aut dysfunction. RESULTS: Mean SSR amplitudes and ESC values showed differences between HC and patients with MSA or PN (p < 0.05), but not in patients with VVS or PD. Absence of SSR was associated with abnormal ESC (p < 0.05). Patients with abnormal CV-Aut dysfunction had lower ESC (p< 0.05). Palm ESC (P-ESC) and sole ESC (S-ESC) assessment had a sensitivity of 0.91 and 0.95 to predict sudomotor dysfunction, with a specificity of 0.78 and 0.85, respectively. The area under ROC curve was 0.905 and 0.98, respectively. CONCLUSIONS: ESC in palms and soles has a high diagnostic accuracy for sudomotor dysfunction as detected by absent SSR in patients with MSA and PN.