Diabetic polyneuropathies: update on research definition, diagnostic criteria and estimation of severity

VEGF-loaded ROS-responsive nanodots improve the structure and function of sciatic nerve lesions in type II diabetic peripheral neuropathy

Diabetic peripheral neuropathy (DPN) is a prevalent complication of diabetes mellitus (DM), significantly contributing to the risk of amputation and mortality. Reactive oxygen species (ROS) can induce both neurological and structural harm through direct impact and pyroptosis, underscoring the critical role of ROS regulation in mitigating DPN. In this research endeavor, we propose harnessing the inherent antioxidant properties of sulfhydryl groups by grafting them onto gold nanodots through an amidation reaction, resulting in the creation of ROS-responsive AuNDs. Additionally, we aim to synthesize AuNDs-VEGF, wherein VEGF is attached to AuNDs via electrostatic interactions, as a therapeutic strategy for addressing DPN in rat models. The results of in vivo experiments showed that AuNDs and AuNDs-VEGF nanoparticles could increase the nerve conduction velocity, shorten the latency of nerve conduction in the sciatic nerve, promote the regeneration of nerve trophectodermal vessels, improve the structure and function of the sciatic nerve, reduce the apoptosis of neural cells, and alleviate the atrophy of the gastrocnemius muscle. Thus, VEGF-loaded ROS-responsive nanodots present a promising avenue for ameliorating diabetic peripheral neuropathy. This innovative approach not only extends the application possibilities of nanodots but also introduces a novel avenue for the treatment of diabetic neuropathy.

Biochemical use of neurofilament light polypeptide and vitamin B12 in relation to diabetic polyneuropathy in Danish adolescents with type 1 diabetes: a cross-sectional study

INTRODUCTION

The aim of this study was to investigate serum Neurofilament Light polypeptide (NfL) as a biomarker for diabetic polyneuropathy (DPN) in adolescents with type 1 diabetes (T1D). Secondarily, to investigate vitamin B12 (B12) deficiency as a cause for DPN in adolescents with T1D.

RESEARCH DESIGN AND METHODS

Cross-sectional study. Sixty Danish adolescents with T1D (age 15-18 years, diabetes duration >5 years) and 23 age-matched control subjects were included. Based on nerve conduction studies (NCS), intraepidermal nerve fibre density (IENFD) and neurological examination, patients were divided into three groups: (1) T1D without DPN, (2) T1D with subclinical DPN and (3) T1D with confirmed DPN. Blood levels of NfL, B12, B12-binding protein holotranscobalamin (HoloTC) and methylmalonic acid (MMA) were determined.

RESULTS

Twenty-four of the adolescents were without DPN, twenty-one had subclinical DPN and eight had confirmed DPN. NCS was not conducted in three participants and four patients did not have blood samples taken. There were no significant differences in NfL levels or any of the B12 parameters between any of the groups.

CONCLUSIONS

NfL used in a cross-sectional manner was not found useful to distinguish between the adolescents with DPN and those without. Vitamin B12 deficiency did not contribute to neuropathy in Danish adolescents with T1D.

Diabetic peripheral neuropathy detection of type 2 diabetes using machine learning from TCM features: a cross-sectional study

AIMS

Diabetic peripheral neuropathy (DPN) is the most common complication of diabetes mellitus. Early identification of individuals at high risk of DPN is essential for successful early intervention. Traditional Chinese medicine (TCM) tongue diagnosis, one of the four diagnostic methods, lacks specific algorithms for TCM symptoms and tongue features. This study aims to develop machine learning (ML) models based on TCM to predict the risk of diabetic peripheral neuropathy (DPN) in patients with type 2 diabetes mellitus (T2DM).

METHODS

A total of 4723 patients were included in the analysis (4430 with T2DM and 293 with DPN). TFDA-1 was used to obtain tongue images during a questionnaire survey. LASSO (least absolute shrinkage and selection operator) logistic regression model with fivefold cross-validation was used to select imaging features, which were then screened using best subset selection. The synthetic minority oversampling technique (SMOTE) algorithm was applied to address the class imbalance and eliminate possible bias. The area under the receiver operating characteristic curve (AUC) was used to evaluate the model's performance. Four ML algorithms, namely logistic regression (LR), random forest (RF), support vector classifier (SVC), and light gradient boosting machine (LGBM), were used to build predictive models for DPN. The importance of covariates in DPN was ranked using classifiers with better performance.

RESULTS

The RF model performed the best, with an accuracy of 0.767, precision of 0.718, recall of 0.874, F-1 score of 0.789, and AUC of 0.77. With a value of 0.879, the LGBM model appeared to be the best regarding recall Age, sweating, dark red tongue, insomnia, and smoking were the five most significant RF features. Age, yellow coating, loose teeth, smoking, and insomnia were the five most significant features of the LGBM model.

CONCLUSIONS

This cross-sectional study demonstrates that the RF and LGBM models can screen for high-risk DPN in T2DM patients using TCM symptoms and tongue features. The identified key TCM-related features, such as age, tongue coating, and other symptoms, may be advantageous in developing preventative measures for T2DM patients.

Remote Monitoring of Chemotherapy-Induced Peripheral Neuropathy by the NeuroDetect iOS App: Observational Cohort Study of Patients With Cancer

BACKGROUND

Chemotherapy-induced peripheral neuropathy (CIPN) is a common and debilitating adverse effect of neurotoxic chemotherapy characterized by symptoms such as numbness, tingling, and weakness. Effective monitoring and detection of CIPN are crucial for avoiding progression to irreversible symptoms. Due to the inconvenience of clinic-based objective assessment, CIPN detection relies primarily on patients' reporting of subjective symptoms, and patient-reported outcomes are used to facilitate CIPN detection. Our previous study found evidence that objective functional assessments completed within a smartphone app may differentiate patients with and those without CIPN after treatment.

OBJECTIVE

This prospective, longitudinal observational cohort study aimed to determine the feasibility and accuracy of app-based remote monitoring of CIPN in patients with cancer undergoing neurotoxic chemotherapeutic treatment and to conduct exploratory comparisons of app-based functional CIPN monitoring versus patient-reported outcome-only monitoring.

METHODS

The NeuroDetect app (Medable Inc) includes subjective EORTC (European Organization for Research and Treatment of Cancer) Quality of Life Questionnaire (QLQ)-20-item scale (CIPN20) and 6 objective functional assessments that use smartphone sensors to mimic neurological examinations, such as walking, standing, and manual dexterity tests. The functional assessment data were collected from patients with cancer undergoing neurotoxic chemotherapy, and a neurological examination was conducted at the end of treatment to diagnose CIPN in the feet (CIPN-f) or CIPN in the hands (CIPN-h). Various classification models including NeuroDetect features only (NeuroDetect Model) CIPN20-only (CIPN20 Model) or a combination of both (Combined Model) were trained and evaluated for accuracy in predicting CIPN probability.

RESULTS

Of the 45 patients who completed functional assessments and neurological examinations, 24 had CIPN-f, and 29 had CIPN-h. The NeuroDetect Model could discriminate between patients with and those without CIPN-f (area under the curve=83.8%, comparison with no information rate P=.02) but not CIPN-h (area under the curve=67.9%, P=.18). The rolling rotation features from the eyes-closed phase of the Romberg Stance assessment showed the greatest contribution to CIPN-f (40% of total variable importance) and the Finger Tapping assessment showed the greatest contribution to CIPN-h (85% of total variable importance). The NeuroDetect Model had numerically, and at some time points statistically, superior performance to the CIPN20 Model in both CIPN-f and CIPN-h, particularly before and early in treatment. The Combined Model numerically, though not statistically, outperformed either assessment strategy individually, indicating that the combination of functional and patient-reported assessment within a smartphone may be optimal to CIPN detection.

CONCLUSIONS

Our findings demonstrate the feasibility of integrating subjective and objective CIPN assessment into a smartphone app for remote, longitudinal CIPN monitoring. Studies of larger patient cohorts are needed to refine the app-based CIPN detection models and determine whether their use in practice improves CIPN detection.

Cutaneous Carbonyl Stress Is Associated With Nerve Dysfunction in Recent-Onset Type 2 Diabetes

OBJECTIVE

Endogenous carbonyl stress leads to the formation of advanced glycation end products (AGEs). AGEs represent a potential target to prevent or treat diabetic sensorimotor polyneuropathy (DSPN). The current study aimed to characterize cutaneous carbonyl stress, oxidative stress, immune cells, and endothelial cell damage in early type 2 diabetes compared with normal glucose tolerance (NGT) using novel cutaneous biomarkers.

RESEARCH DESIGN AND METHODS

Included were 160 individuals recently (≤12 months) diagnosed with type 2 diabetes and 144 with NGT from the German Diabetes Study baseline cohort. Nerve function was assessed using electrophysiological, quantitative sensory, and clinical testing. Skin biopsies were obtained to analyze intraepidermal nerve fiber density, AGE autofluorescence, argpyrimidine area, and endothelial cell area. In addition, skin autofluorescence was measured noninvasively using the AGE reader. A subgroup with type 2 diabetes (n = 80) was reassessed 5 years later.

RESULTS

After adjustment for sex, age, HbA1c, LDL cholesterol, and BMI, argpyrimidine area (17.5 ± 18.8 vs. 11.7 ± 12.7%) was higher in recent-onset type 2 diabetes than in NGT (P < 0.05). AGE autofluorescence was inversely correlated with nerve conduction (e.g., peroneal motor nerve conduction velocity: r = -0.346) and positively with AGE reader measurements in type 2 diabetes (r = 0.358, all P < 0.05), but not in NGT. Higher baseline AGE autofluorescence and lower endothelial cell area predicted the deterioration of clinical and neurophysiological measures after 5 years.

CONCLUSIONS

Cutaneous AGE markers were associated with neurophysiological deficits in recent-onset type 2 diabetes and predicted their progression after 5 years, substantiating the role of carbonyl stress in the development of early DSPN.

What is associated with painful polyneuropathy? A cross-sectional analysis of symptoms and signs in patients with painful and painless polyneuropathy

ABSTRACT

It is still unclear how and why some patients develop painful and others painless polyneuropathy. The aim of this study was to identify multiple factors associated with painful polyneuropathies (NeuP). A total of 1181 patients of the multicenter DOLORISK database with painful (probable or definite NeuP) or painless (unlikely NeuP) probable or confirmed neuropathy were investigated clinically, with questionnaires and quantitative sensory testing. Multivariate logistic regression including all variables (demographics, medical history, psychological symptoms, personality items, pain-related worrying, life-style factors, as well as results from clinical examination and quantitative sensory testing) and machine learning was used for the identification of predictors and final risk prediction of painful neuropathy. Multivariate logistic regression demonstrated that severity and idiopathic etiology of neuropathy, presence of chronic pain in family, Patient-Reported Outcomes Measurement Information System Fatigue and Depression T-Score, as well as Pain Catastrophizing Scale total score are the most important features associated with the presence of pain in neuropathy. Machine learning (random forest) identified the same variables. Multivariate logistic regression archived an accuracy above 78%, random forest of 76%; thus, almost 4 out of 5 subjects can be classified correctly. This multicenter analysis shows that pain-related worrying, emotional well-being, and clinical phenotype are factors associated with painful (vs painless) neuropathy. Results may help in the future to identify patients at risk of developing painful neuropathy and identify consequences of pain in longitudinal studies.

Accuracy and reliability of the Ipswich touch test in identifying loss of protective sensation among diabetic patients

OBJECTIVE

To evaluate the accuracy of the Ipswich touch test compared to the 10-g monofilament test for identifying of loss of protective sensation in Thai patients with diabetes mellitus.

METHODS

A cross-sectional observational study was conducted on Thai patients with diabetes mellitus who attended routine annual foot check-ups in an outpatient diabetes clinic. The loss of protective sensation was assessed by the Ipswich touch test and compared with the Semmes-Weinstein 10-g monofilament test. Sensitivity, specificity, predictive values and likelihood ratios were calculated to measure the accuracy of the Ipswich touch test against 10-g monofilament as a reference standard. The interrater reliability of the Ipswich touch test was assessed by two raters.

RESULTS

In a study of 283 diabetic patients, 10-g monofilament detected a 25 % prevalence of loss protective sensation. The Ipswich touch test demonstrated a good diagnostic accuracy, with a sensitivity of 70.8 %, specificity of 98.6 %, and an area under the curve of 0.85 when compared to 10-g monofilament. Positive and negative predictive values were 94.4 % and 90.8 % respectively. The positive likelihood ratio was 49.82, and the negative likelihood ratio was 0.30. Interrater reliability, assessed with two raters in a subset of 93 participants, yielded a kappa of 0.88, indicating almost perfect agreement.

CONCLUSIONS

The Ipswich Touch Test demonstrated good accuracy and interrater reliability compared to the standard 10-g monofilament, thus establishing its effectiveness as a valuable diagnostic tool for identifying loss of protective sensation among diabetic patients. However, its relatively low sensitivity suggests it should be used with caution as a screening tool.

Does the Relationship of the Autonomic Symptoms Questionnaire COMPASS 31 with Cardiovascular Autonomic Tests Differ between Type 1 and Type 2 Diabetes Mellitus?

BACKGRUOUND

The aim was to investigate if autonomic symptoms questionnaire Composite Autonomic Symptom Score (COMPASS) 31 has different association with cardiovascular autonomic neuropathy (CAN) and diagnostic performance between type 1 diabetes mellitus (T1DM) and type 2 diabetes mellitus (T2DM).

METHODS

Seventy-nine participants with T1DM and 140 with T2DM completed COMPASS 31 before cardiovascular reflex tests (CARTs) for CAN, and assessment of symptoms, signs, vibration, and thermal perception thresholds for diabetic polyneuropathy (DPN) diagnosis.

RESULTS

COMPASS 31 total weighted score (TWS) was similar in the two groups, but significantly associated with confirmed CAN only in T1DM (P=0.0056) and not T2DM group (P=0.1768) and correlated with CARTs score more strongly in T1DM (rho=0.356, P=0.0016) than in T2DM group (rho=0.084, P=0.3218) (P=0.016). Only in T1DM and not T2DM group, the area under the receiver operating characteristic curve (AUC) reached a fair diagnostic accuracy (>0.7) for confirmed CAN (0.73±0.07 vs. 0.61±0.08) and DPN (0.75±0.06 vs. 0.68±0.05), although without a significant difference. COMPASS 31 TWS (cut-off 16.44) reached acceptable diagnostic performance in T1DM, with sensitivity for confirmed CAN 81.2% and sensitivity and specificity for DPN 76.3% and 78%, compared to T2DM group (all <70%). AUC for DPN of orthostatic intolerance domain was higher in T1DM compared to T2DM group (0.73±0.05 vs. 0.58±0.04, P=0.027).

CONCLUSION

COMPASS 31 is more weakly related to CAN in T2DM than in T1DM, with a fair diagnostic accuracy for confirmed CAN only in T1DM. This difference supports a multifactorial origin of symptoms and should be considered when using COMPASS 31.

Prediction Model for Polyneuropathy in Recent-Onset Diabetes Based on Serum Neurofilament Light Chain, Fibroblast Growth Factor-19 and Standard Anthropometric and Clinical Variables

BACKGROUND

Diabetic sensorimotor polyneuropathy (DSPN) is often asymptomatic and remains undiagnosed. The ability of clinical and anthropometric variables to identify individuals likely to have DSPN might be limited. Here, we aimed to integrate protein biomarkers for reliably predicting present DSPN.

METHODS

Using the proximity extension assay, we measured 135 neurological and protein biomarkers of inflammation in blood samples of 423 individuals with recent-onset diabetes from the German Diabetes Study (GDS). DSPN was diagnosed based on the Toronto Consensus Criteria. We constructed (i) a protein-based prediction model using LASSO logistic regression, (ii) an optimised traditional risk model with age, sex, waist circumference, height and diabetes type and (iii) a model combining both. All models were bootstrapped to assess the robustness, and optimism-corrected AUCs (95% CI) were reported.

RESULTS

DSPN was present in 16% of the study population. LASSO logistic regression selected the neurofilament light chain (NFL) and fibroblast growth factor-19 (FGF-19) as the most predictive protein biomarkers for detecting DSPN in individuals with recent-onset diabetes. The protein-based model achieved an AUC of 0.66 (0.59, 0.73), while the traditional risk model had an AUC of 0.66 (0.61, 0.74). However, combined features boosted the model performance to an AUC of 0.72 (0.67, 0.79).

CONCLUSION

We developed a prediction model for DSPN in recent-onset diabetes based on two protein biomarkers and five standard anthropometric, demographic and clinical variables. The model has a fair discrimination performance and might be used to inform the referral of patients for further testing.

Quantification of white matter hyperintensities in type 1 diabetes and its relation to neuropathy and clinical characteristics

AIMS

The aims were to quantify periventricular and deep white matter hyperintensities (WMHs) in adults with type 1 diabetes with different neuropathic phenotypes and to correlate WMH measurements to explanatory factors in diabetes.

METHODS

WMH measurements were obtained from brain magnetic resonance imaging of 56 adults with type 1 diabetes in subgroups including painful diabetic peripheral neuropathy (DPN), painless DPN, without DPN and 20 healthy controls using Fazekas scale and automatic segmentation analysis.

RESULTS

No differences in Fazekas assessed WMHs were found (individuals with periventricular lesions: diabetes 66 % vs. controls 40 %, p = 0.063, deep lesions: diabetes 52 % vs. controls 50 %, p = 1.0). Using automatic detection, there were no significant differences in count of periventricular (p = 0.30) or deep (p = 0.31) WMHs. Higher periventricular lesion burden was present in diabetes compared with controls (0.21 % vs. 0.06 %, p = 0.048), which was associated with more severe DPN, increased age, decreased cognitive function, and reduced volumetric and metabolic brain measures (all p < 0.05).

CONCLUSIONS

Our findings indicate increased burden of periventricular WMHs in diabetes which were associated to DPN severity and measurements reflecting neurodegeneration. Deep WMHs, often considered as chronic ischemic, were not significantly different. Mechanisms reflecting neurodegeneration and accelerated brain aging could be an overlooked aspect of peripheral and central neuropathy.

Phase Angle of Bioelectrical Impedance Analysis as an Indicator for Diabetic Polyneuropathy in Type 2 Diabetes Mellitus

CONTEXT

Due to the heterogenous clinical symptoms and deficits, the diagnosis of diabetic polyneuropathy (DPN) is still difficult in clinical routines, leading to increased morbidity and mortality.

OBJECTIVE

We studied the correlation of phase angle (PhA) of bioelectrical impedance analysis (BIA) with clinical, laboratory, and physical markers of DPN to evaluate PhA as a possible diagnostic method for DPN.

MATERIALS AND METHODS

In this cross-sectional observational study as part of the Heidelberg Study on Diabetes and Complications, we examined 104 healthy individuals and 205 patients with type 2 diabetes mellitus (T2D), among which 63 had DPN. The PhA was calculated from multifrequency BIA. Nerve conduction studies, quantitative sensory testing (QST) and diffusion-weighted magnetic resonance neurography to determine fractional anisotropy (FA) reflecting peripheral nerve integrity were performed.

RESULTS

T2D patients with DPN had lower PhA values (5.71 ± 0.10) compared to T2D patients without DPN (6.07 ± 0.08, P = .007, + 6.1%) and healthy controls (6.18 ± 0.08, P < .001, + 7.9%). Confounder-adjusted analyses showed correlations of the PhA with conduction velocities and amplitudes of the peroneal (β=.28; β=.31, P < .001) and tibial nerves (β=.28; β=.32, P < .001), Z-scores of QST (thermal detection β=.30, P < .05) and the FA (β=.60, P < .001). Receiver-operating characteristic analysis showed similar performance of PhA in comparison to the mentioned diagnostic methods.

CONCLUSION

The study shows that PhA is, in comparison to other test systems used, at least an equally good and much easier to handle investigator-independent marker for detection of DPN.

Development of a transformer-based deep learning algorithm for diabetic peripheral neuropathy classification using corneal confocal microscopy images

Background

Diabetic peripheral neuropathy (DPN) is common and can go unnoticed until it is firmly developed. This study aims to establish a transformer-based deep learning algorithm (DLA) to classify corneal confocal microscopy (CCM) images, identifying DPN in diabetic patients.

Methods

Our classification model differs from traditional convolutional neural networks (CNNs) using a Swin transformer network with a hierarchical architecture backbone. Participants included those with (DPN+, n = 57) or without (DPN-, n = 37) DPN as determined by the updated Toronto consensus criteria. The CCM image dataset (consisting of 570 DPN+ and 370 DPN- images, with five images selected from each participant's left and right eyes) was randomly divided into training, validation, and test subsets at a 7:1:2 ratio, considering individual participants. The effectiveness of the algorithm was assessed using diagnostic accuracy measures, such as sensitivity, specificity, and accuracy, in conjunction with Grad-CAM visualization techniques to interpret the model's decisions.

Results

In the DPN + group (n = 12), the transformer model successfully predicted all participants, while in the DPN- group (n = 7), one participant was misclassified as DPN+, with an area under the curve (AUC) of 0.9405 (95% CI 0.8166, 1.0000). Among the DPN + images (n = 120), 117 were correctly classified, and among the DPN- images (n = 70), 49 were correctly classified, with an AUC of 0.8996 (95% CI 0.8502, 0.9491). For single-image predictions, the transformer model achieved a superior AUC relative to the ResNet50 model (0.8761, 95% CI 0.8155, 0.9366), the Inception_v3 model (0.8802, 95% CI 0.8231, 0.9374), and the DenseNet121 model (0.8965, 95% CI 0.8438, 0.9491).

Conclusion

Transformer-based networks outperform CNN-based networks in rapid binary DPN classification. Transformer-based DLAs have clinical DPN screening potential.

Nerve decompression for diabetic peripheral neuropathy with nerve entrapment: a narrative review

Diabetic peripheral neuropathy (DPN) is one of the most common complications of diabetes which primarily affects the sensory nervous system. Pain is the most common complaint that prompts patients to seek medical advice. With various presentations and intricate pathological mechanisms, diabetic peripheral neuropathic pain is currently the most crucial and challenging aspect of managing diabetic complications. As a heterogeneous disorder, there is no medication or treatment modality that is effective for all types of DPN and its associated neuropathic pain. Peripheral nerve decompression provides a new option for treating patients with diabetic peripheral neuropathic pain in the lower extremities. However, the clinical applicability of nerve decompression has been debated since it was first proposed. This review discusses the theoretical basis of nerve decompression, the clinical indications, and the progress of basic research based on the pathological mechanisms and nerve impairment patterns of diabetic peripheral neuropathic pain. The heterogeneity of DPN patients is summarized in terms of three aspects: complex pathophysiological mechanisms, multilevel nervous system involvement, and various nerve impairment properties. Identifying the presence of nerve entrapment among complex pathophysiological mechanisms is the key to successful outcomes. Tinel signs, focal pain, mechanical allodynia, and two-point discrimination were reported to be prognostic factors for good surgical outcomes, and their predictive ability might stem from their association with the early stage of entrapment neuropathy.

Prevalence, patterns, and determinants of vascular complications of type 2 diabetes in a teaching hospital in Addis Ababa, Ethiopia: a retrospective study

BACKGROUND

Patients with type 2 diabetes mellitus (T2D) have an increased risk of vascular complications. Despite the rise in the prevalence of T2D and its complications throughout the globe, there is a paucity of data regarding the prevalence and determinants of vascular complications of T2D in Ethiopia. Hence, this study aimed to assess the prevalence, patterns, and determinants of the microvascular and macrovascular complications of T2D among adult patients attending a teaching hospital in Addis Ababa, Ethiopia.

METHODS

A retrospective study was done by reviewing the electronic health records of adult patients with T2D attending the general medical and endocrine referral clinics of Yekatit 12 Hospital Medical College, Addis Ababa, Ethiopia, from June 1, 2023, to November 30, 2023. Statistical Package for Social Sciences (SPSS), version 25, was used to analyze the data. Descriptive analysis was used to summarize the sociodemographic, clinical, and laboratory profiles as well as the patterns of vascular complications of T2D. Bivariate and multivariate logistic regression models were fitted, and the crude odds ratio (COR) and adjusted odds ratio (AOR), together with the 95% confidence interval (CI), were computed to identify the determinants of microvascular and macrovascular complications of T2D.

RESULTS

A total of 272 patients with T2D were included in this study; 50.5% were females, and the mean (± standard deviation) age was 56.3 ± 12.8 years. The majority of patients (62.5%) had diabetes for ≥ 5 years. More than half (51.5%) had poor glycemic control with glycated haemoglobin (HbA1c) value of ≥ 7%. The overall prevalence of vascular complications was 39%. The prevalence of microvascular complications was 23.5%, the most common being neuropathy (11.8%), and the prevalence of macrovascular complications was 21%, the most common being coronary artery disease (12.1%). The determinants of microvascular complications were age ≥ 60 years (AOR = 2.25, 95% CI: 1.17, 4.33), diabetes duration of ≥ 5 years (5-10 years [AOR = 3.13, 95% CI: 1.37, 7.18], and > 10 years [AOR = 3.88, 95% CI: 1.66, 9.06], and HbA1c value of ≥ 7% (AOR = 2.21, 95% CI: 1.14, 4.28). The odds of developing macrovascular complications were higher with diabetes duration of ≥ 5 to 10 years (AOR = 2.89, 95% CI: 1.37, 6.12) as compared with diabetes duration of < 5 years.

CONCLUSIONS

This study demonstrated a high prevalence of microvascular and macrovascular complications in adult patients with T2D. Older age, prolonged duration of diabetes, and poor glycemic control were identified as the determinants for the development of microvascular complications  of T2D, while prolonged duration of diabetes was the determining factor for the development of macrovascular complications. Hence, targeted initiatives are required to enhance the prevention and early detection of vascular complications of T2D in resource-limited countries like Ethiopia.

Determinants of Orthostatic Hypotension in Type 2 Diabetes: Is Cardiac Autonomic Neuropathy the Main Factor?

OBJECTIVES

To evaluate the determinants of orthostatic hypotension (OH) in type 2 diabetes (T2D) and the usefulness of Δheart rate (HR)/Δsystolic blood pressure (SBP), index of cardiac baroreflex function, in identifying neurogenic OH.

METHODS

In 208 participants with T2D, we diagnosed early cardiovascular autonomic neuropathy (CAN) and confirmed CAN according to 1 and 2 HR-based cardiovascular reflex tests (HR-CARTs). Through OH test we defined OH as SBP falls of ≥20 and ≥30 mm Hg with supine SBPs of <140 and ≥140 mm Hg, respectively. In participants with OH, we used the lying-to-standing and OH test and its diagnostic accuracy for neurogenic OH (as OH plus confirmed HR-CAN).

RESULTS

OH was present in 25 participants and associated with lower HR-CART scores, higher glycosylated hemoglobin level, the presence of CAN, retinopathy, and peripheral vascular disease, the absence of hypertension, and physical activity (all, P < .05) but not with interfering drugs and β-blockers. In a multiple logistic regression, HR-CAN was the main determinant of OH (odds ratio, 4.74) with physical activity and hypertension (odds ratios, 0.16 and 0.23; R2 = 0.22). ΔHR/ΔSBP had a good diagnostic accuracy for neurogenic OH (area under the receiver operating characteristic curve, 0.816 ± 0.087) and, at the cutoff of 0.5 bpm/mm Hg, a sensitivity of 100% and specificity of 63.2%.

CONCLUSION

CAN remains the primary determinant of OH in T2D but does not explain all its variance. The index ΔHR/ΔSBP may represent a useful clinical tool to identify neurogenic OH.

Whether coagulation dysfunction influences the onset and progression of diabetic peripheral neuropathy: A multicenter study in middle-aged and aged patients with type 2 diabetes

BACKGROUND

Nearly half of patients with diabetes experience diabetic peripheral neuropathy (DPN), resulting in a mere 53% survival rate within 3 years. Aberrations in coagulation function have been implicated in the pathogenesis of microvascular complications, prompting the need for a thorough investigation into its role as a contributing factor in the development and progression of DPN.

METHODS

Data were gathered from 1211 type 2 diabetes patients admitted to five centers from September 2018 to October 2022 in China. DPN was evaluated by symptoms and electromyography. Motor and sensory nerve conduction velocity (NCV) was appraised and the NCV sum score was calculated for the median, ulnar, and peroneal motor or sensory nerves.

RESULTS

Patients with DPN exhibited alterations in coagulation function. (i) Specifically, they exhibited prolonged thrombin time (p = 0.012), elevated fibrinogen (p < 0.001), and shortened activated partial thromboplastin time (APTT; p = 0.026) when compared to the control group. (ii) After accounting for potential confounders in linear regression, fibrinogen, and D-dimer were negatively related to the motor NCV, motor amplitude values, and mean velocity and amplitude. Also, fibrinogen was associated with higher Michigan neuropathy screening instrument (MNSI) scores (β 0.140; p = 0.001). This result of fibrinogen can be validated in the validation cohort with 317 diabetic patients. (iii) Fibrinogen was independently associated with the risk of DPN (OR 1.172; p = 0.035). In the total age group, DPN occurred at a slower rate until the predicted fibrinogen level reached around 3.75 g/L, after which the risk sharply escalated.

CONCLUSIONS

Coagulation function is warranted to be concerned in patients with type 2 diabetes to predict and prevent the occurrence of DPN in clinical practice.

The Association between the Severity of Distal Sensorimotor Polyneuropathy and Increased Carotid Atherosclerosis in Individuals with Type 2 Diabetes

BACKGROUND

Diabetes contributes to a spectrum of complications encompassing microvascular and macrovascular disorders. This study aimed to explore the correlation between distal sensorimotor polyneuropathy (DSPN) severity and heightened carotid atherosclerosis among individuals with type 2 diabetes mellitus (T2DM). Method: Participants underwent comprehensive assessments including nerve conduction studies (NCS), Toronto Clinical Neuropathy Score (TCNS) evaluations, assessment of cardiometabolic risk factors, and carotid sonography studies covering dynamic and morphological parameters. The resistance index (RI), pulsatility index (PI), peak systolic velocity (PSV), and end-diastolic velocity (EDV) in both the common carotid artery (CCA) and internal carotid artery (ICA), carotid intima-media thickness (IMT), and carotid plaque score (CPS) were also measured. Peripheral nerve function severity was assessed using composite amplitude scores (CAS) derived from NCS.

RESULTS

Individuals with DSPN exhibited lower EDV in the CCA and ICA (p < 0.0001 and p = 0.002), higher PI and RI in both CCA and ICA (all p < 0.0001), and higher CPS (p = 0.002). They also demonstrated a higher prevalence of retinopathy as an underlying condition, higher index HbA1c, and reduced estimated glomerular filtration rate (eGFR) (all p < 0.0001). Multiple linear regression analysis revealed significant associations where eGFR, ICA-PI, index HbA1c, waist circumference, and age were correlated with CAS. Meanwhile, diabetes duration, waist circumference, age, and index HbA1c showed significant associations with TCNS.

CONCLUSIONS

Our study suggests that individuals with T2DM who exhibit more severe carotid atherosclerosis may not only be at increased risk of developing DSPN but also may experience greater severity of DSPN. PI in both the CCA and ICA, along with the CPS, serve as surrogate biomarkers for DSPN severity.

Investigating the Effectiveness of Electroacupuncture for Diabetic Peripheral Neuropathy and Exploring the Feasibility of Infrared Thermography as an Efficacy Assessment Tool: Study Protocol for a Randomized Controlled Trial

Introduction

Diabetic peripheral neuropathy (DPN) affects patients' quality of life significantly. To date, selecting the appropriate treatment remains challenging. While electroacupuncture (EA) has shown promise as an effective adjunct therapy for DPN, and infrared thermography (IRT) has been considered as a potential predictor of treatment efficacy, the evidence for both remains inconclusive. As such, the objectives of this trial are twofold: to ascertain the efficacy of EA for DPN, and to explore the feasibility of IRT as an adjunctive objective tool for efficacy assessment.

Methods

The study was designed as a randomized, parallel, controlled trial. It spanned over 6 weeks of treatment and an additional 4 weeks of follow-up. 104 eligible participants will be stratified for severity of disease: mild with Toronto clinical scoring system(TCSS) score 6-8, moderate (TCSS score 9-11), and severe (TCSS score 12-19), and each level will be randomised in a 1:1 ratio into a EA group and waiting-list group. The waiting-list group received only the current conventional medication, while the EA group received an additional 12 EA sessions on top of the conventional medication. The primary outcome indicators is nerve conduction velocity (NCV), which will be tested at the baseline and week 6. Total clinical efficiency, TCSS, Clinical symptoms score of Traditional Chinese Medicine (TCM), Patient global impression of change(PGIC), Temperature of regions of interest (ROIs), and Physico chemical examination will be used as secondary outcome indicators. In addition, safety assessment will be determined based on adverse events during the trial.

Conclusion

The expected results of this study will determine whether EA improves efficacy in the treatment of DPN with an acceptable safety profile, and investigating variations in the efficacy of EA across different levels of DPN severity. Furthermore, it will explore the viability of IRT as an objective measure for evaluating treatment effectiveness for DPN.

Clinical Trial Registration

ClinicalTrials.gov identifier, NCT06054087.

Development and Progression of Polyneuropathy Over 5 Years in Patients With Type 2 Diabetes

BACKGROUND AND OBJECTIVES

There is a need for knowledge regarding the natural course of diabetic polyneuropathy (DPN), a complication in type 2 diabetes (T2D). The aim of this study was to examine the development of DPN over time.

METHODS

Patients with newly diagnosed T2D, recruited from a national cohort, and controls without diabetes of similar age and sex, underwent sensory phenotyping in 2016-2018. The Toronto consensus criteria were used to classify patients into possible, probable, and confirmed DPN. For this 5-year, observational, follow-up, cohort study, all participants were invited to a reexamination combining bedside sensory examination, quantitative sensory testing (QST), nerve conduction studies (NCSs), and skin biopsies measuring intraepidermal nerve fiber density (IENFD) in order to compare phenotypic and diagnostic changes over time.

RESULTS

Of the baseline 389 patients and 97 controls, 184 patients (median [interquartile range] diabetes duration 5.9 [4.1-7.4] years, mean hemoglobin A1c [HbA1c] 51 ± 11 mmol/mol at baseline) and 43 controls completed follow-up (46.9%). Confirmed DPN was present in 35.8% and 50.3%, probable DPN in 27.2% and 14.6%, possible DPN in 17.2% and 16.6%, and no DPN in 15.2% and 17.9% at baseline and follow-up, respectively. The estimated prevalence (95% CI) of confirmed DPN was 33.5% (24.9-42.1) compared with 22.7% (17.5-28.0) at baseline. During the follow-up period, 43.9% of patients with probable DPN developed confirmed DPN. Progression of neuropathy occurred in 16.5% and 24.7% and regression in 5.9% and 18.6% of patients based on NCS and IENFD, respectively. Progression based on NCS and/or IENFD was associated with higher baseline waist circumference and triglycerides, and regression with lower baseline HbA1c. Patients with at least probable DPN at baseline but neither patients without DPN nor controls developed increased spread of hyposensitivity, more hyposensitivity on QST and lower NCS z-scores at follow-up, and worsening of nerve parameters at follow-up correlated with higher baseline triglycerides.

DISCUSSION

In patients with well-regulated T2D, the proportion of patients with confirmed DPN increased over 5 years driven by progression from probable DPN. A large proportion of patients progressed, and a smaller proportion regressed on nerve parameters. Higher triglycerides correlated with this progression and may constitute a risk factor.

Engineered exosomes as a prospective therapy for diabetic foot ulcers

Diabetic foot ulcer (DFU), characterized by high recurrence rate, amputations and mortality, poses a significant challenge in diabetes management. The complex pathology involves dysregulated glucose homeostasis leading to systemic and local microenvironmental complications, including peripheral neuropathy, micro- and macro-angiopathy, recurrent infection, persistent inflammation and dysregulated re-epithelialization. Novel approaches to accelerate DFU healing are actively pursued, with a focus on utilizing exosomes. Exosomes are natural nanovesicles mediating cellular communication and containing diverse functional molecular cargos, including DNA, mRNA, microRNA (miRNA), lncRNA, proteins, lipids and metabolites. While some exosomes show promise in modulating cellular function and promoting ulcer healing, their efficacy is limited by low yield, impurities, low loading content and inadequate targeting. Engineering exosomes to enhance their curative activity represents a potentially more efficient approach for DFUs. This could facilitate focused repair and regeneration of nerves, blood vessels and soft tissue after ulcer development. This review provides an overview of DFU pathogenesis, strategies for exosome engineering and the targeted therapeutic application of engineered exosomes in addressing critical pathological changes associated with DFUs.

Biodegradable microspheres via orally deliver celastrol with ameliorated neuropathic pain in diabetes rats

The treatment of peripheral neuropathy resulting from diabetes primarily emphasizes neurotrophic medications. However, a growing body of clinical studies indicates that neuroinflammation plays a significant role in the pathogenesis of neuropathic pain. This has spurred active exploration of treatment strategies leveraging nanomedicine for diseases, aiming for superior therapeutic outcomes. In this context, we have developed biodegradable nanoparticles made of polylactic-co-glycolic acid, loaded with triptolide (pCel), designed to alleviate somatic cell neuropathic pain induced by diabetes. Treatment with pCel notably reduced levels of reactive oxygen species and apoptosis in vitro. Furthermore, the progression of streptozotocin-induced diabetes, characterized by elevated renal function indices (blood urea nitrogen, creatinine), liver function indices (bilirubin, alkaline phosphatase) and decreased levels of albumin and globulin, was mitigated following pCel administration. Importantly, oral treatment with pCel significantly inhibited mechanical allodynia and the activation of the sciatic glial cells in diabetic rats. These findings indicate that this synthetic, biodegradable nanomedicine exhibits excellent stability, biocompatibility and catalytic activity, making it a promising and innovative approach for the management of chronic pain conditions associated with diabetic neuropathy.

HbA1c and the risk of developing peripheral neuropathy in childhood-onset type 1 diabetes: A follow-up study over 3 decades

AIMS

We have evaluated long-term weighted mean HbA1c (wHbA1c), HbA1c variability, diabetes duration, and lipid profiles in relation to the development of diabetic peripheral neuropathy (DPN), nephropathy, and retinopathy in childhood-onset type 1 diabetes.

MATERIALS AND METHODS

In a longitudinal cohort study, 49 patients (21 women) with childhood-onset type 1 diabetes were investigated with neurophysiological measurements, blood tests, and clinical examinations after a diabetes duration of 7.7 (±3.3) years (baseline) and followed with repeated examinations for 30.6 (±5.2) years. We calculated wHbA1c by integrating the area under all HbA1c values since the diabetes diagnosis. Lipid profiles were analysed in relation to the presence of DPN. Long-term fluctuations of HbA1c variability were computed as the standard deviation of all HbA1c measurements. Data regarding the presence of other diabetes complications were retrieved from medical records.

RESULTS

In this follow-up study, 51% (25/49) of the patients fulfilled electrophysiological criteria for DPN. In nerve conduction studies, there was a deterioration in the amplitudes and conduction velocities for the median, peroneal, and sural nerves over time. Patients with DPN had a longer duration of diabetes, higher wHbA1c, and increased HbA1c variability. The lowest wHbA1c value associated with the development of DPN was 62 mmol/mol (7.8%). The presence of albuminuria and retinopathy was positively correlated with the presence of neuropathy.

CONCLUSIONS

More than half of the patients had developed DPN after 30 years. None of the patients who developed DPN had a wHbA1c of less than 62 mmol/mol (7.8%).

Longitudinal artificial intelligence-based deep learning models for diagnosis and prediction of the future occurrence of polyneuropathy in diabetes and prediabetes

OBJECTIVE

The objective of this study was to develop artificial intelligence-based deep learning models and assess their potential utility and accuracy in diagnosing and predicting the future occurrence of diabetic distal sensorimotor polyneuropathy (DSPN) among individuals with type 2 diabetes mellitus (T2DM) and prediabetes.

METHODS

In 394 patients (T2DM=300, Prediabetes=94), we developed a DSPN diagnostic and predictive model using Random Forest (RF)-based variable selection techniques, specifically incorporating the combined capabilities of the Clinical Toronto Neuropathy Score (TCNS) and nerve conduction study (NCS) to identify relevant variables. These important variables were then integrated into a deep learning framework comprising Convolutional Neural Networks (CNNs) and Long Short-Term Memory (LSTM) networks. To evaluate temporal predictive efficacy, patients were assessed at enrollment and one-year follow-up.

RESULTS

RF-based variable selection identified key factors for diagnosing DSPN. Numbness scores, sensory test results (vibration), reflexes (knee, ankle), sural nerve attributes (sensory nerve action potential [SNAP] amplitude, nerve conduction velocity [NCV], latency), and peroneal/tibial motor NCV were candidate variables at baseline and over one year. Tibial compound motor action potential amplitudes were used for initial diagnosis, and ulnar SNAP amplitude for subsequent diagnoses. CNNs and LSTMs achieved impressive AUC values of 0.98 for DSPN diagnosis prediction, and 0.93 and 0.89 respectively for predicting the future occurrence of DSPN. RF techniques combined with two deep learning algorithms exhibited outstanding performance in diagnosing and predicting the future occurrence of DSPN. These algorithms have the potential to serve as surrogate measures, aiding clinicians in accurate diagnosis and future prediction of DSPN.

Expert opinion on screening, diagnosis and management of diabetic peripheral neuropathy: a multidisciplinary approach

The proposed expert opinion aimed to address the current knowledge on conceptual, clinical, and therapeutic aspects of diabetic peripheral neuropathy (DPN) and to provide a guidance document to assist clinicians for the best practice in DPN care. The participating experts consider the suspicion of the disease by clinicians as a key factor in early recognition and diagnosis, emphasizing an improved awareness of the disease by the first-admission or referring physicians. The proposed "screening and diagnostic" algorithm involves the consideration of DPN in a patient with prediabetes or diabetes who presents with neuropathic symptoms and/or signs of neuropathy in the presence of DPN risk factors, with careful consideration of laboratory testing to rule out other causes of distal symmetric peripheral neuropathy and referral for a detailed neurological work-up for a confirmative test of either small or large nerve fiber dysfunction in atypical cases. Although, the first-line interventions for DPN are currently represented by optimized glycemic control (mainly for type 1 diabetes) and multifactorial intervention (mainly for type 2 diabetes), there is a need for individualized pathogenesis-directed treatment approaches for DPN. Alpha-lipoic acid (ALA) seems to be an important first-line pathogenesis-directed agent, given that it is a direct and indirect antioxidant that works with a strategy targeted directly against reactive oxygen species and indirectly in favor of endogenous antioxidant capacity for improving DPN conditions. There is still a gap in existing research in the field, necessitating well-designed, robust, multicenter clinical trials with sensitive endpoints and standardized protocols to facilitate the diagnosis of DPN via a simple and effective algorithm and to track progression of disease and treatment response. Identification of biomarkers/predictors that would allow an individualized approach from a potentially disease-modifying perspective may provide opportunities for novel treatments that would be efficacious in early stages of DPN, and may modify the natural course of the disease. This expert opinion document is expected to increase awareness among physicians about conceptual, clinical, and therapeutic aspects of DPN and to assist them in timely recognition of DPN and translating this information into their clinical practice for best practice in the management of patients with DPN.

The effect of foot somatosensory loss in postural control during Functional reach test in patients with diabetic polyneuropathy: A controlled study

BACKGROUND

In patients with diabetic polyneuropathy (DPN), differences in postural control due to losing the lower limb somatosensory information were reported. However, it is still unclear by which mechanisms the dynamic postural instability is caused.

OBJECTIVES

This study aimed to investigate postural control differences and neuromuscular adaptations resulting from foot somatosensory loss due to DPN.

METHODS

In this controlled cross-sectional study, fourteen DPN patients and fourteen healthy controls performed the Functional Reach Test (FRT) as a dynamic task. The postural control metrics were simultaneously measured using force plate, motion capture system, and surface electromyography (sEMG). The main metrics including reach length (FR), FR to height ratio (FR/H), displacement of CoM and CoP, moment arm (MA), and arch height ratio. Also, kinematic (range of motion of ankle, knee, and hip joints), and sEMG metrics (latencies and root mean square amplitudes of ankle and hallux muscles) were measured. To compare variables between groups, the independent sample T-test for (normally distributed) and the Mann-Whitney U test (non-normally distributed) were used.

RESULTS

The subjects' reach length (FR), FR to height ratio, absolute MA, and displacement of CoM were significantly shorter than controls, while displacement of CoP was not significant. Arch height ratio was found significantly lower in DPN patients. We observed that CoM was lagging CoP in patients (MA = + 0.89) while leading in controls (MA = -1.60). Although, the muscles of patients showed significantly earlier activation, root mean square sEMG amplitudes were found similar. Also, DPN patients showed significantly less hip flexion, knee extension, and ankle plantar flexion.

CONCLUSIONS

This study presented that decreasing range of motion at lower limbs' joints and deterioration in foot function caused poor performance at motor execution during FRT in DPN patients.

Electrophysiological grading scale for polyneuropathy severity

OBJECTIVE

To establish a simple electrophysiological scale for patients with distal symmetric axonal polyneuropathy, in order to promote standardized and informative electrodiagnostic reporting, and understand the complex relationship between electrophysiological and clinical polyneuropathy severity.

METHODS

We included 76 patients with distal symmetric axonal polyneuropathy, from a cohort of 151 patients with polyneuropathy prospectively recruited from November 2016 to May 2017. Patients underwent nerve conduction studies (NCS), were evaluated by the Toronto Clinical Neuropathy Score (TCNS), and additional tests. The number of abnormal NCS parameters was determined, within the range of 0-4, considering low amplitude or conduction velocity in the sural and peroneal nerve.

RESULTS

Higher number of NCS abnormalities was associated with higher TCNS, indicating more severe polyneuropathy. Polyneuropathy severity per the TCNS was most frequently (63%-70%) mild in patients with a low (0-1) number of NCS abnormalities, and most frequently (57%-67%) severe in patients with a high number (3-4) of NCS abnormalities, while patients with an intermediate (2) number of NCS abnormalities showed mainly mild and moderate severity with equal distribution (40%).

CONCLUSIONS

A simple NCS classification system can objectively grade polyneuropathy severity, although significant overlap exists especially at the intermediate range, underscoring the importance of clinical based scoring.

Efficacy of electro-acupuncture versus sham acupuncture for diabetic peripheral neuropathy: study protocol for a three-armed randomised controlled trial

INTRODUCTION

Specific treatment for diabetic peripheral neuropathy (DPN) is still lacking, and acupuncture may relieve the symptoms. We intend to investigate the efficacy and safety of electro-acupuncture (EA) in alleviating symptoms associated with DPN in diabetes.

METHODS AND ANALYSIS

This multicentre, three-armed, participant- and assessor-blind, randomised, sham-controlled trial will recruit 240 eligible participants from four hospitals in China and will randomly assign (1:1:1) them to EA, sham acupuncture (SA) or usual care (UC) group. Participants in the EA and SA groups willl receive either 24-session EA or SA treatment over 8 weeks, followed by an 8-week follow-up period, while participants in the UC group will be followed up for 16 weeks. The primary outcome of this trial is the change in DPN symptoms from baseline to week 8, as rated by using the Total Symptom Score. The scale assesses four symptoms: pain, burning, paraesthesia and numbness, by evaluating the frequency and severity of each. All results will be analysed with the intention-to-treat population.

ETHICS AND DISSEMINATION

The protocol has been approved by the Ethics Committee of the Beijing University of Chinese Medicine (Identifier: 2022BZYLL0509). Every participant will be informed of detailed information about the study before signing informed consent. The results of this trial will be published in a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

ChiCTR2200061408.

High serum levels of CCL11/Eotaxin-1 are associated with diabetic sensorimotor polyneuropathy and peripheral nerve function but not with cardiac autonomic neuropathy in people with type 2 diabetes

AIMS

To investigate whether higher serum CCL11/Eotaxin-1, a biomarker for aging and neurodegenerative and neuroinflammatory disorders, is associated with diabetic sensorimotor polyneuropathy (DSPN), peripheral nerve dysfunction, and cardiac autonomic neuropathy in people with type 2 diabetes.

METHODS

This cross-sectional study included 106 patients with type 2 diabetes and 40 healthy controls, matched for the age and sex distribution of the diabetes group as a whole. The CC chemokines CCL11/Eotaxin-1 and CCL22/MDC were measured in fasting serum samples. DSPN and peripheral nerve function were assessed by neurological examination and nerve conduction studies, and cardiac autonomic function, by heart rate variability (HRV) and corrected QT (QTc) time. The cardio-ankle vascular index (CAVI) was measured as a marker for arterial stiffness.

RESULTS

Serum CCL11/Eotaxin-1 levels were significantly higher in diabetic patients than in healthy controls (183 ± 63.5 vs. 113.1 ± 38.5 pg/ml, p < 0.001), but serum CCL22/MDC levels were not significantly different between the two groups. In the diabetes group, the serum CCL11/Eotaxin-1 level was positively correlated with ulnar and sural nerve conduction velocities (p = 0.0009, p = 0.0208, respectively) and sensory nerve action potential (p = 0.0083), and CAVI (p = 0.0005), but not with HRV indices or QTc time, and serum CCL22/MDC was not significantly correlated with any indices of nerve conduction. In a model adjusted for age and duration of diabetes, serum CCL11/Eotaxin-1 was still associated with ulnar nerve conduction velocity (p = 0.02124). Serum CCL11/Eotaxin-1, but not CCL22/MDC, was significantly higher in patients with than in those without DSPN (208.2 ± 71.6 vs. 159.1 ± 45.1 pg/ml, respectively; p < 0.0001).

CONCLUSIONS

Serum CCL11/Eotaxin-1 is elevated in patients with DSPN and is associated with peripheral nerve dysfunction, in particular sensory nerve conduction velocity, suggesting that serum CCL11/Eotaxin-1 may be a potential biomarker for DSPN.

CLINICAL TRIAL REGISTRATION

University Hospital Medical Information Network (UMIN) Clinical Trials Registry (UMIN000040631).

Association of dietary patterns with diabetes-related comorbidities varies among diabetes endotypes

BACKGROUND AND AIMS

Differences of dietary pattern adherence across the novel diabetes endotypes are unknown. This study assessed adherence to pre-specified dietary patterns and their associations with cardiovascular risk factors, kidney function, and neuropathy among diabetes endotypes.

METHODS AND RESULTS

The cross-sectional analysis included 765 individuals with recent-onset (67 %) and prevalent diabetes (33 %) from the German Diabetes Study (GDS) allocated into severe autoimmune diabetes (SAID, 35 %), severe insulin-deficient diabetes (SIDD, 3 %), severe insulin-resistant diabetes (SIRD, 5 %), mild obesity-related diabetes (MOD, 28 %), and mild age-related diabetes (MARD, 29 %). Adherence to a Mediterranean diet score (MDS), Dietary Approaches to Stop Hypertension (DASH) score, overall plant-based diet (PDI), healthful (hPDI) and unhealthful plant-based diet index (uPDI) was derived from a food frequency questionnaire and associated with cardiovascular risk factors, kidney function, and neuropathy using multivariable linear regression analysis. Differences in dietary pattern adherence between endotypes were assessed using generalized mixed models. People with MARD showed the highest, those with SIDD and MOD the lowest adherence to the hPDI. Adherence to the MDS, DASH, overall PDI, and hPDI was inversely associated with high-sensitivity C-reactive protein (hsCRP) among people with MARD (β (95%CI): -9.18 % (-15.61; -2.26); -13.61 % (-24.17; -1.58); -19.15 % (-34.28; -0.53); -16.10 % (-28.81; -1.12), respectively). Adherence to the PDIs was associated with LDL cholesterol among people with SAID, SIRD, and MOD.

CONCLUSIONS

Minor differences in dietary pattern adherence (in particular for hPDI) and associations with markers of diabetes-related complications (e.g. hsCRP) were observed between endotypes. So far, evidence is insufficient to derive endotype-specific dietary recommendations.

TRIAL REGISTRATION

Clinicaltrials.gov: NCT01055093.

Biomarkers and signaling pathways of diabetic nephropathy and peripheral neuropathy: possible therapeutic intervention of rutin and quercetin

Diabetic nephropathy and peripheral neuropathy are the two main complications of chronic diabetes that contribute to high morbidity and mortality. These conditions are characterized by the dysregulation of multiple molecular signaling pathways and the presence of specific biomarkers such as inflammatory cytokines, indicators of oxidative stress, and components of the renin-angiotensin system. In this review, we systematically collected and collated the relevant information from MEDLINE, EMBASE, ELSEVIER, PUBMED, GOOGLE, WEB OF SCIENCE, and SCOPUS databases. This review was conceived with primary objective of revealing the functions of these biomarkers and signaling pathways in the initiation and progression of diabetic nephropathy and peripheral neuropathy. We also highlighted the potential therapeutic effectiveness of rutin and quercetin, two plant-derived flavonoids known for their antioxidant and anti-inflammatory properties. The findings of our study demonstrated that both flavonoids can regulate important disease-promoting systems, such as inflammation, oxidative stress, and dysregulation of the renin-angiotensin system. Importantly, rutin and quercetin have shown protective benefits against nephropathy and neuropathy in diabetic animal models, suggesting them as potential therapeutic agents. These findings provide a solid foundation for further comprehensive investigations and clinical trials to evaluate the potential of rutin and quercetin in the management of diabetic nephropathy and peripheral neuropathy. This may contribute to the development of more efficient and comprehensive treatment approaches for diabetes-associated complications.

Neuropathy 10-15 years after Roux-en-Y gastric bypass for severe obesity: A community-controlled nerve conduction study

Objective

We searched for long-term peripheral nerve complications 10-15 years after Roux-en-Y gastric bypass surgery (RYGB), using a comprehensive nerve conduction study (NCS) protocol.

Methods

Patients (n = 175, mean age 52.0, BMI 35.2) and 86 community-controls (mean age 56.8, BMI 27.2) had NCS of one upper and lower limb. New abnormality scores from 27 polyneuropathy-relevant (PNP27s) and four carpal tunnel syndrome-relevant NCS-measures (CTS4s) were compared between groups with non-parametric statistics. Estimated prevalences were compared by 95 % confidence limits. The clinical neurophysiologist's diagnosis was retrieved from hospital records (PNP-ncs, CTS-ncs, other).

Results

Abnormality score did not differ between RYGB and control groups (PNP27s: 1.9 vs 1.7, CTS4s: 0.7 vs 0.6, p > 0.29). BMI correlated weakly with CTS4s in patients (rho = 0.19, p = 0.01), and less with PNP27s (rho = 0.12, p = 0.12). Polyneuropathy (PNP-ncs) prevalence was 12 % in patients and 8 % in controls. CTS-ncs prevalence was 21 % in patients and 10 % in controls (p = 0.04).

Conclusions

NCS-based abnormality scores did not differ between patients 10-15 years after RYGB and community-recruited controls, neither for PNP nor CTS.

Significance

Long-term polyneuropathic complications from RYGB have probably been avoided by modern treatment guidelines. NCS-diagnosed CTS is common in overweight RYGB patients. RYGB-patients with significant neuropathic symptoms need clinical evaluation.

Distinguish different sensorimotor performance of the hand between the individuals with diabetes mellitus and chronic kidney disease through deep learning models

Diabetes mellitus and chronic kidney disease represent escalating global epidemics with comorbidities akin to neuropathies, resulting in various neuromuscular symptoms that impede daily performance. Interestingly, previous studies indicated differing sensorimotor functions within these conditions. If assessing sensorimotor features can effectively distinguish between diabetes mellitus and chronic kidney disease, it could serve as a valuable and non-invasive indicator for early detection, swift screening, and ongoing monitoring, aiding in the differentiation between these diseases. This study classified diverse diagnoses based on motor performance using a novel pinch-holding-up-activity test and machine learning models based on deep learning. Dataset from 271 participants, encompassing 3263 hand samples across three cohorts (healthy adults, diabetes mellitus, and chronic kidney disease), formed the basis of analysis. Leveraging convolutional neural networks, three deep learning models were employed to classify healthy adults, diabetes mellitus, and chronic kidney disease based on pinch-holding-up-activity data. Notably, the testing set displayed accuracies of 95.3% and 89.8% for the intra- and inter-participant comparisons, respectively. The weighted F1 scores for these conditions reached 0.897 and 0.953, respectively. The study findings underscore the adeptness of the dilation convolutional neural networks model in distinguishing sensorimotor performance among individuals with diabetes mellitus, chronic kidney disease, and healthy adults. These outcomes suggest discernible differences in sensorimotor performance across the diabetes mellitus, chronic kidney disease, and healthy cohorts, pointing towards the potential of rapid screening based on these parameters as an innovative clinical approach.

Comprehensive management of children and adolescents with type 1 diabetes mellitus through personalized physical exercise and education using an mHealth system: The Diactive-1 study protocol

Introduction

The use of new technologies presents an opportunity to promote physical activity, especially among young people with type 1 diabetes (T1DM), who tend to be less active compared to their healthy counterparts. The aim of this study is to investigate the impact of a personalized resistance exercise program, facilitated by the Diactive-1 App, on insulin requirements among children and adolescents diagnosed with T1DM.

Methods and analysis

A minimum of 52 children and adolescents aged 8-18 years, who were diagnosed with T1DM at least 6 months ago, will be randomly assigned to either a group engaging in an individualized resistance exercise program at least 3 times per week over a 24-week period or a waiting-list control group. The primary outcome will be the daily insulin dose requirement. The secondary outcomes will include glycemic control, cardiometabolic profile, body composition, vascular function, physical fitness, 24-hour movement behaviors, diet, and psychological parameters. The usability of the app will also be assessed.

Ethics and dissemination

Ethical approval to conduct this study has been granted by the University Hospital of Navarra Research Board (PI_2020/140). Parents or legal guardians of minors participating in the study will provide written consent, while children and adolescents will sign an assent form to indicate their voluntary agreement. The trial's main findings will be shared through conference presentations, peer-reviewed publications, and communication directly with participating families. This study aims to offer valuable insights into the holistic management of children and adolescents with T1DM by utilizing personalized exercise interventions through an mHealth system.

Trial registration

NCT06048757.

The effectiveness of neurodynamic techniques in patients with diabetic peripheral neuropathy: Study protocol for a randomized sham-controlled trial

Background

Diabetic peripheral neuropathy (DPN) is one of the most common complications of diabetes mellitus (DM). DPN is the primary risk factor for diabetic foot ulcers that can cause amputation. Although several observational studies have investigated the morphological and biomechanical characteristics of peripheral nerves in DPN, interventional studies regarding the effectiveness of neurodynamic techniques (NDT) in DPN patients are confined to a handful. The effects of NDT on neuropathy severity, nerve conduction parameters, quality of life (QoL), and mechanosensitivity have not been explored yet in this population.

Materials and Methods

Forty type 2 DPN (T2DPN) patients, diagnosed based on an electrodiagnosis study, will be recruited into two groups. The experimental group will receive the tibial nerve's real proximal and distal slider techniques in addition to DPN standard treatment as a basic treatment, and the control group will receive the tibial nerve's sham proximal and distal slider techniques along with the basic treatment for eight sessions twice a week. Baseline and post-intervention assessments will be based on the Michigan diabetic neuropathy score (MDNS) (primary outcome), tibial nerve conduction parameters, neuropathy-specific quality of life (Neuro QoL) questionnaire, and straight leg raising range of motion (SLR ROM) (secondary outcomes).

Results

This study is expected to last approximately seven months, depending on recruitment. The results of the study will be published in a peer-reviewed journal.

Conclusions

The present study will evaluate the efficacy of NDT on the primary and secondary outcome measurements in DPN patients.

[The intensity of neuropathic pain and the severity of insomnia in diabetic polyneuropathy]

OBJECTIVE

To determine the prevalence of insomnia and the effectiveness of its treatment in patients with a painful form of diabetic polyneuropathy (DPN).

MATERIAL AND METHODS

Fifty patients with the painful form of DPN were randomly divided into 2 groups: the standard therapy group (ST) and the extended therapy group (ET). In the ST group, a single lesson on sleep hygiene was conducted, in the ET group there were 3-4 face-to-face individual sessions for the treatment of insomnia for two weeks. Both groups were interviewed at the time of hospitalization, after 3 and 6 months. The severity of polyneuropathy and the nature of neuropathic pain were assessed using the Neuropathic Neuropathy Impairment Score in the Lower Limbs (NIS-LL) and the Neuropathy Total Symptom Score - 9 (NTSS-9); the intensity of pain was assessed using a Visual Analog Scale (VAS). Sleep disorders were analyzed using the Pittsburgh Sleep Quality Index (PSQI) and the Insomnia Severity Index (ISI).

RESULTS

Sleep disorders of varying severity were observed in 82% of patients in the initial survey. In both groups, improvement in sleep quality was noted during treatment, but significantly better results were in the ET group, the ISI score after 6 months was 7.15±2.08 for the ST group and 3.07±2.49 for the ET group (p<0.0001). In the ST group, there was no significant decrease in the intensity of pain and the severity of polyneuropathy in dynamics. In the ET group, a significant decrease in NTSS-9 and VAS scores was found during the initial survey and after 6 months (p<0.0001). The intensity of pain also significantly decreased in the ET group compared with the ST group (p<0.0001) at the end of follow-up, which indicates the importance of sleep normalization in the treatment of neuropathic pain.

CONCLUSION

Most patients with the painful form of DPN have insomnia. Treatment of insomnia has shown its effectiveness as part of a multimodal approach to the managing of neuropathic pain in DPN and improving the quality of life of patients.

Histostructure of bone tissue after restoration of blood flow in patients with ischemic form of diabetic foot syndrome

OBJECTIVE

Aim: To study the histostructure of bone tissue in case of disruption of its blood supply and after restored blood flow in patients with ischemic form of diabetic foot syndrome..

PATIENTS AND METHODS

Materials and Methods: The histostructure of bone fragments in 25 patients with isolated ischemic form of diabetic foot syndrome was studied. Bone tissue biopsy specimens from 6 patients against the background of progressive ischemia were studied. In addition, the histostructure of bone tissue after revascularization with complete restoration of blood flow in 19 patients was studied.

RESULTS

Results: The analysis of bone tissue biopsy specimens showed that disruption of blood supply of the limb tissues for a long time leads to impaired matrix calcification, decreased cortex thickness, widening of osteon channels and sparse trabecular network in the bone structure. Such changes were the signs of bone resorption that was not clinically or radiologically apparent. Revascularization with full restoration of blood flow promoted the appearance of signs of bone tissue regeneration in the form of vessel formation in bone and periosteum.

CONCLUSION

Conclusions: Adequate blood flow is an important clinical factor contributing to the restoration of bone regeneration in patients with ischemic form of diabetic foot syndrome.

Sensory Phenotypes Provide Insight Into the Natural Course of Diabetic Polyneuropathy

We aimed to investigate the characteristics and longitudinal course of sensory phenotypes identified through quantitative sensory testing (QST) in the frame of diabetic sensorimotor polyneuropathy (DSPN). A total of 316 individuals with diabetes were examined (type 2 diabetes 78.8%), 250 of whom were undergoing follow-up visits at 1, 2, and/or 4 (2.88 ± 1.27) years. Allocation into four sensory phenotypes (healthy, thermal hyperalgesia [TH], mechanical hyperalgesia [MH], and sensory loss [SL]) at every time point was based on QST profiles of the right foot. Cross-sectional analysis demonstrated a gradual worsening of clinical and electrophysiological sensory findings and increased DSPN prevalence across the groups, culminating in SL. Motor nerve impairment was observed solely in the SL group. Longitudinal analysis revealed a distinct pattern in the developmental course of the phenotype (from healthy to TH, MH, and finally SL). Those with baseline MH exhibited the highest risk of transition to SL. Reversion to healthy status was uncommon and mostly observed in the TH group. Among those without DSPN initially, presence or future occurrence of SL was associated with a three- to fivefold higher likelihood of DSPN development. Our comprehensive longitudinal study of phenotyped patients with diabetes elucidates the natural course of DSPN. QST-based sensory examination together with other tools for phenotyping may be useful in determining the natural course of diabetic neuropathy to identify patients at high risk of DSPN and guide preventive and therapeutic interventions.

ARTICLE HIGHLIGHTS

The course of diabetic sensorimotor polyneuropathy (DSPN) development, from healthy status to overt DSPN, is poorly understood. We studied the characteristics and longitudinal appearance of lower-extremity sensory phenotypes (healthy, thermal hyperalgesia [TH], mechanical hyperalgesia [MH], and sensory loss [SL]) identified through quantitative sensory testing in individuals with diabetes. There was an increasing severity and patterned order of longitudinal appearance across healthy, TH, MH, and SL phenotypes. SL was most strongly associated with formal DSPN. Our findings provide insight into the natural history of DSPN. Sensory phenotyping can be implemented to identify high-risk individuals and those most likely to benefit from therapeutic interventions.

Increased Frequency of Giant Miniature End-Plate Potentials at the Neuromuscular Junction in Diabetic Rats

There is a need for research addressing the functional characteristics of the motor end-plate in diabetes to identify mechanisms contributing to neuromuscular dysfunction. Here, we investigated the effect of diabetes on spontaneous acetylcholine release in the rat neuromuscular junction. We studied two randomized groups of male Wistar rats (n = 7 per group, 350 ± 50 g, 12-16 weeks of age): one with streptozotocin-induced experimental diabetes, and a healthy control group without diabetes. After 8 weeks of monitoring after diabetes induction, rats in both groups were anesthetized with pentobarbital. Then, the diaphragm muscle was dissected for electrophysiological recordings of miniature end-plate potentials (MEPPs) using a single electrode located at the region of the muscle end-plate. All experiments were conducted at environmental temperature (20-22 °C) in rat Ringer solution with constant bubbling carbogen (95% O2, 5% CO2). Compared to healthy controls, in the diaphragm neuromuscular end-plate derived from diabetic rats, the MEPPs were higher in amplitude and frequency, and the proportion of giant MEPPs was elevated (7.09% vs. 1.4% in controls). Our results showed that diabetes affected the acetylcholine MEPP pattern and increased the number of giant potentials compared to healthy controls.

Correlation study of renal function indices with diabetic peripheral neuropathy and diabetic retinopathy in T2DM patients with normal renal function

Background

The anticipation of diabetes-related complications remains a challenge for numerous T2DM patients, as there is presently no effective method for early prediction of these complications. This study aims to investigate the association between renal function-related indicators and the occurrence of peripheral neuropathy and retinopathy in individuals diagnosed with type 2 diabetes mellitus (T2DM) who currently have normal renal function.

Methods

Patients with T2DM who met the criteria were selected from the MMC database and divided into diabetic peripheral neuropathy (DPN) and diabetic retinopathy (DR) groups, with a total of 859 and 487 patients included, respectively. Multivariate logistic regression was used to analyze the relationship between blood urea nitrogen (BUN), creatinine (Cr), uric acid (UA), urine albumin(ALB), albumin-to-creatinine ratio (ACR), estimated glomerular filtration rate (eGFR), and diabetic peripheral neuropathy and retinopathy. Spearman correlation analysis was used to determine the correlation between these indicators and peripheral neuropathy and retinopathy in diabetes.

Results

In a total of 221 patients diagnosed with DPN, we found positive correlation between the prevalence of DPN and eGFR (18.2, 23.3, 35.7%, p < 0.05). Specifically, as BUN (T1: references; T2:OR:0.598, 95%CI: 0.403, 0.886; T3:OR:1.017, 95%CI: 0.702, 1.473; p < 0.05) and eGFR (T1: references; T2:OR:1.294, 95%CI: 0.857, 1.953; T3:OR:2.142, 95%CI: 1.425, 3.222; p < 0.05) increased, the odds ratio of DPN also increased. Conversely, with an increase in Cr(T1: references; T2:OR:0.86, 95%CI: 0.56, 1.33; T3:OR:0.57, 95%CI: 0.36, 0.91; p < 0.05), the odds ratio of DPN decreased. Furthermore, when considering sensitivity and specificity, eGFR exhibited a sensitivity of 65.2% and specificity of 54.4%, with a 95% confidence interval of 0.568-0.656.

Conclusion

In this experimental sample, we found a clear positive correlation between eGFR and DPN prevalence.

The effect of type 2 diabetes and diabetic peripheral neuropathy on predictive grip force control

This study investigated the impact of type 2 diabetes and diabetic peripheral neuropathy on grip force control during object manipulation. The study included three age-matched groups: type 2 diabetes alone (n = 11), type 2 diabetes with neuropathy (n = 13), and healthy controls (n = 12). Grip force control variables derived from lifting and holding an experimental cup were the ratio between grip force and load forces during lifting (GFR), latency 1 and latency 2, which represented the time between the object's grip and its lift-off from the table, and the period between object's lift-off and the grip force peak, respectively; time lag, which denoted the time difference between the grip and load force peaks during the lifting phase, and finally static force, which was the grip force average during the holding phase. Grip force control variables were compared between groups using one-way ANOVA and Kruskal-Wallis test. Post-hoc analysis was used to compare differences between groups. GFR and latency 1 showed significant differences between groups; the type 2 diabetes with neuropathy group showed larger GFR than the type 2 diabetes alone and healthy control groups. The latency 1was longer for the group with neuropathy in comparison with the health control group. There were no significant differences between groups for latency 2, time lag, and static force. Our results showed impaired GFR and latency 1 in participants with type 2 diabetes with neuropathy while the time lag was preserved. People with type 2 diabetes alone might not have any deficits in grip force control. Higher grip forces might expose people with type 2 diabetes and diabetic peripheral neuropathy to the risk of fatigue and injuring their hands. Future studies should investigate strategies to help people with type 2 diabetes with neuropathy adjust grip forces during object manipulation.

The pathogenesis of painful diabetic neuropathy and clinical presentation

Diabetic neuropathy is a common complication of diabetes that affects up to 50% of patients during the course of the disease; 20-30% of the patients also develop neuropathic pain. The mechanisms underlying neuropathy are not known in detail, but both metabolic and vascular factors may contribute to the development of neuropathy. The development of the most common type of neuropathy is insidious, often starting distally in the toes and feet and gradually ascending up the leg and later also involving fingers and hands. The symptoms are mainly sensory with either sensory loss or positive symptoms with different types of paresthesia or painful sensations. In more advanced cases motor dysfunction may occur, causing gait disturbances and falls. The diagnosis of neuropathy is based on history and a careful examination, which includes a sensory examination of both large and small sensory nerve fiber function, as well as an examination of motor function and deep tendon reflexes of the lower limbs. Attention needs to be paid to the feet including examination of the skin, joints, and vascular supply. Nerve conduction studies are rarely needed to make a diagnosis of neuropathy. In patients with clear motor deficit or with an asymmetrical presentation, additional electrophysiological examination may be necessary. Early detection of diabetic neuropathy is important to avoid further irreversible injury to the peripheral nerves.

Serum neurofilament light chain - A potential biomarker for polyneuropathy in type 2 diabetes?

AIMS

To investigate the relationship between neurofilament light chain (NfL) and the presence and severity of diabetic polyneuropathy (DPN).

METHODS

We performed cross-sectional analysis of data from 178 participants of the ADDITION-Denmark cohort of people with screen-detected type 2 diabetes and 32 healthy controls. Biobank serum samples were analyzed for NfL using single-molecule array. DPN was defined by Toronto criteria for confirmed DPN. Original and axonal nerve conduction study (NCS) sum z-scores were used as indicators of the severity of DPN and peripheral nerve damage.

RESULTS

39 (21.9%) participants had DPN. Serum NfL (s-NfL) was significantly higher in participants with DPN (18.8 ng/L [IQR 14.4; 27.9]) than in participants without DPN (15.4 ng/L [IQR 11.7; 20.1]). There were no unadjusted s-NfL differences between controls (17.6 ng/L [IQR 12.7; 19.8]) and participants with or without DPN. Higher original and axonal NCS sum z-scores were associated with 10% higher s-NfL (10.2 and 12.1% [95% CI's 4.0; 16.8 and 6.6; 17.9] per 1 SD). The AUC of s-NfL for DPN was 0.63 (95% CI 0.52; 0.73).

CONCLUSIONS

S-NfL is unlikely to be a reliable biomarker for the presence of DPN. S-NfL is however associated tothe severity of the nerve damage underlying DPN.

Diabetic Polyneuropathy and Physical Activity in Type 1 Diabetes Mellitus: A Cross-Sectional Study

BACKGROUND

The purpose of this study is to access whether a personal attitude to physical activity (PA) may influence the appearance of diabetic polyneuropathy (DPN) patients with well-controlled type 1 diabetes mellitus.

METHODS

Ninety patients attending the diabetes technology outpatient clinic were enrolled. DPN was investigated according to the Toronto consensus diagnostic criteria. PA was assessed using the International Physical Activity Questionnaire.

RESULTS

PA was low in 21.1%, moderate in 42.2% and high in 36.7% of patients. According to Toronto criteria, we defined two categories: the first one with DPN absent or possible (57 (63.3%)) and a second one with DPN certain or probable (33 (36.7%)). The χ2-test of the PA groups and the DPN categories showed a statistically significant difference (p < 0.001), with less neuropathy in patients belonging to the group of moderate/high PA. Exposure to a minimum of 600 MET minutes/week was protective factor against the onset of DPN (odd ratio 0.221, c.i. 0.068-0.720, p = 0.012).

CONCLUSIONS

This study suggests that DPN is less present in type 1 diabetic patients with good metabolic control and a good personal habit of PA. Moderate-to-vigorous PA of at least 600 MET minutes/week might be a protective factor against DPN.

Cardiovascular autonomic neuropathy in patients with type 2 diabetes with and without sensorimotor polyneuropathy

BACKGROUND AND AIMS

Cardiovascular autonomic neuropathy (CAN) in patients with diabetes is associated with poor prognosis. We aimed to assess signs of CAN and autonomic symptoms and to investigate the impact of sensorimotor neuropathy on CAN by examining type 2 diabetes patients with (DPN [distal sensorimotor polyneuropathy]) and without distal sensorimotor polyneuropathy (noDPN) and healthy controls (HC). Secondarily, we aimed to describe the characteristics of patients with CAN.

METHODS

A population of 374 subjects from a previously described cohort of the Danish Centre for Strategic Research in Type 2 Diabetes (DD2) were included. Subjects were examined with the Vagus™ device for the diagnosis of CAN, where two or more abnormal cardiovascular autonomic reflex tests indicate definite CAN. Autonomic symptoms were assessed with Composite Autonomic Symptom Score 31 (COMPASS 31) questionnaire. DPN was defined according to the Toronto consensus panel definition.

RESULTS

Definite CAN was present in 22% with DPN, 7% without DPN and 3% of HC, and 91% of patients with definite CAN had DPN. Patients with DPN and definite CAN reported higher COMPASS 31 scores compared to patients with noDPN (20.0 vs. 8.3, p < 0.001) and no CAN (22.1 vs. 12.3, p = 0.01). CAN was associated with HbA1c and age in a multivariate logistic regression analysis but was not associated with IEFND or triglycerides.

INTERPRETATION

One in five patients with DPN have CAN and specific CAN characteristics may help identify patients at risk for developing this severe diabetic complication. Autonomic symptoms were strongly associated with having both DPN and CAN, but too unspecific for diagnosing CAN.

Assessing diabetic polyneuropathy in Spanish-speaking patients: Translation and validation of the Toronto Clinical Neuropathy Score

BACKGROUND AND AIMS

Diabetic sensorimotor polyneuropathy (DSP) is a common complication of diabetes. The Toronto Clinical Neuropathy Score (TCNS) is a useful tool for detecting DSP. However, it is not available in Spanish. The study aimed to translate and culturally adapt the TCNS and modified (mTCNS) scales into Spanish and evaluate their measurement properties.

METHODS

A multistep forward-backward method was used for translation and cultural adaptation. A panel of physicians subjected the final Spanish versions of TCNS and mTCNS (TCÑS, mTCÑS) to cognitive debriefing. Consecutive patients with diabetes mellitus and DSP were recruited from an outpatient clinic, and the TCÑS and mTCÑS were tested for construct validity, along with other measures.

RESULTS

The internal consistency of both TCÑS and mTCÑS was excellent, as evidenced by Cronbach's Alpha coefficients of 0.83 and 0.85, respectively. Furthermore, there was a robust positive correlation between TCÑS and mTCÑS. In addition, TCÑS was found to exhibit a strong negative correlation with sural sensory nerve action potential amplitude (r = -0.9206) and peroneal compound motor action potential amplitude (r = -0.729), while demonstrating a positive and strong correlation with the Michigan Neuropathy Screening Instrument (r = 0.713).

INTERPRETATION

The TCÑS and mTCÑS are reliable and valid translations of the original TCNS. The TCÑS and mTCÑS can be used to diagnose and measure the severity of neuropathy in Spanish-speaking patients with diabetes.