Correlation Between the Severity of Diabetic Peripheral Polyneuropathy and Glycosylated Hemoglobin Levels: A Quantitative Study

Nerve Conduction Study, Sympathetic Skin Response Test, and Demographic Correlates in Type 2 Diabetes Mellitus Patients

OBJECTIVE

To comprehensively assess the relationship between nerve conduction study (NCS), sympathetic skin response (SSR), and demographic factors in patients with diabetic neuropathy, exploring potential risk factors and mechanisms.

METHODS

A retrospective study (N=184) included patients diagnosed with type 2 diabetes mellitus undergoing NCS and SSR. Demographic, clinical, and laboratory data were analyzed. Patients were categorized by diabetic peripheral neuropathy (DPN) and SSR stages for comparative analysis.

RESULTS

HbA1c levels correlated with DPN progression. SSR stages exhibited age-related differences. Height correlated with DPN but not SSR stages. Body mass index showed no significant differences.

CONCLUSION

While DPN progression correlated with glycemic control and duration of diabetes, SSR was influenced by age. Unexpectedly, cholesterol levels remained within the normal range, challenging established concepts. Understanding these relationships is crucial for interpreting test results and developing targeted interventions for diabetic neuropathy.

Leptin Rs7799039 polymorphism is associated with type 2 diabetes mellitus Egyptian patients

BACKGROUND

Leptin (LEP) is an anti-obesity hormone that regulates food intake, energy expenditure, and glucose metabolism. The genetic variants in LEP and the LEP receptor (LEPR) gene may play an important role in the pathogenesis of type 2 diabetes mellitus (T2DM) and obesity. The current study aimed to investigate the association of serum LEP levels, and LEP polymorphisms in LEP (rs7799039, 2548 G/A) with T2DM in Egyptian patients.

METHODS

A total of 205 subjects were included in the present case-control study, consisting of 100 T2DM patients and 105 healthy controls. The anthropometric, psychometric, and biochemical measurements were taken from all the subjects. The genotyping of LEP gene variants was carried out by polymerase chain reaction TaqMan technology. Serum LEP levels were measured by the ELISA technique.

RESULTS

T2DM patients had significantly elevated levels of glycated haemoglobin (HbA1c), fasting blood sugar (FBS), postprandial blood sugar (PPBS), international normalisation ratio (INR), creatinine, urea, cholesterol, triglyceride (TG), and low-density lipoproteins (LDL) and significantly decreased high-density lipoprotein (HDL) compared to healthy subjects. serum LEP levels were significantly decreased p (<0.001) as compared to the control group. LEP gene SNP rs7799039 was associated with an increased diabetic risk with A allele being more frequent in T2DM patients than control subjects. The distribution of the AA genotype and GA genotype of LEP SNP rs7799039 was higher in the diabetic group than control one. In addition, AA + GA genotype carriers had significantly elevated HbA1c, FBS, PPBS, TG, and LDL levels and on the contrary, decreased serum LEP levels compared to GG homozygotes.

CONCLUSION

The genetic polymorphism rs7799039 showed a highly significant correlation with blood LEP. The co-dominant and dominant models of the LEP genetic polymorphism (rs7799039, 2548 G/A) were shown to have a significant correlation with complicated and uncomplicated diabetes individuals, but we have found that serum LEP levels were inversely related with control and diabetes patients. A positive significant association was found between LEP genetic polymorphism (rs7799039, 2548 G/A) and serum LEP in patients and controls. LEP levels and its rs7799039 genetic variant may play a vital role in increasing T2DM susceptibility.

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.

Clinical evaluation of painful diabetes peripheral neuropathy in type 2 diabetes patients: Lessons from expatriates in the United Arab Emirates

BACKGROUND

The high prevalence of Type 2 Diabetes (T2D) in the United Arab Emirates makes it imperative to screen and manage diabetes peripheral neuropathy (DPN) as a priority. Considering the high number of expats from different ethnicity a more thorough approach is necessary. Unfortunately, there are very few studies addressing this issue.

METHODS

The study uses the chi-square test to investigate the dependence of the progression of DNP on ethnic origin. The study uses Pearson Correlation to find the association between three prevalent scales used for the measurement of painful diabetes peripheral neuropathy. Student t-test was used further to investigate the significance of the association.

RESULTS

With a p-value (0.004) and p-value (0.015), the study concludes that DPN risk is dependent on the ethnic origin of the residents. The study further found that there is a significant association between three scales for measuring painful diabetes peripheral neuropathy (pDNP), Douleur Neuropathique en 4 questions (DN4), Neurological Symptoms Score (NSS), and Leeds Assessment of Neuropathic Symptoms and Signs (LANNS). The p-value for all pairwise comparisons for the strength of association between scales was found significant at the level of significance 0.05.

CONCLUSION

The study concludes that the risk of DNP is high in Arab-origin residents in UAE and the reasons behind the finding need to be empirically tested to customize its management. The study further finds a significant association between the score of the three scales used for measuring pDNP.

Metabolic control of diabetic patients assisted by private and public health care systems during the COVID-19 pandemic: A retrospective cohort study

AIMS

We sought to analyze the impacts of social restriction measures imposed by the pandemic COVID-19 on the control of metabolic parameters in diabetic patients.

METHODS

We accessed the medical records of patients who underwent clinical follow-up in the public and private health systems between July 2019 and June 2021. The sample consisted of 288 patients (111 adults and 177 older individuals). A two-way ANOVA mixed model was used to test the effects of intra- (time: baseline and after 24 months) and inter-subject factors. Linear regression analysis was used to predict the difference in body weight considering age, sex, HbA1c, health care system and insulin use.

RESULTS

Among adults, we observed an increase in body weight and LDL-c levels, especially for insulin users (p ≤ 0.05). Adults assisted by the public health care system showed higher HbA1c levels (p = 0.001). Among older individuals using insulin, blood glucose levels decreased (p = 0.019). Body weight decreased in those assisted by the private system (p = 0.005), while glycemia decreased for patients assisted by both health care systems (p = 0.043). The linear regression model confirmed that the increase in body weight was more pronounced in adults than in older individuals.

CONCLUSION

The social restriction measures imposed by the pandemic affected the metabolic control of diabetic patients, especially adults assisted by the public health care system.

Efficacy of perineural hypertonic saline injection versus acupoints of foot in the management of diabetic neuropathy: a multicenter, double-blinded randomized controlled trial

Aim: Painful diabetic polyneuropathy is one of the most common disabling problems worldwide. We aimed to determine if a perineural injection of hypertonic saline compared with foot acupoints decreased the neuropathic pain score in patients with diabetes. Patients & methods/materials: Patients were assigned to receive either perineural or acupoints injection of hypertonic saline 5% in their feet for three weekly sessions. Douleur Neuropathique 4 (DN4) questionnaire for neuropathic pain was assessed. Results: Both groups observed a significant reduction of the DN4 score throughout 8 weeks of follow-up. Conclusion: Both perineural and acupoints hypertonic saline injections of the foot could improve neuropathic pain in patients with diabetes.

Protein pyrrole adducts are associated with elevated glucose indices and clinical features of diabetic diffuse neuropathies

INTRODUCTION

Diabetic neuropathy is the most prevalent complication of diabetes mellitus. Although the precise etiology of this neurological disorder has yet to be defined, elevated blood glucose promotes anerobic glycolysis; this produces excess advanced glycation end-products, many of which have a pyrrole structure. Here, we test the hypothesis that protein pyrrole adducts are associated with elevated glucose indices and some clinical features of diabetic diffuse neuropathies.

METHOD

We investigated the levels of plasma pyrrole adducts and adjusted urinary pyrrole adducts in a group of elderly persons (n = 516, age 60-79) residing in the District of Luohu, Shenzhen, China between 2017 and 2018. Symptoms of distal symmetric polyneuropathy (DSPN) and resting heart rate, a measure of autonomic nervous system function, were collected from participants (n = 258) with elevated glucose indices.

RESULT

Protein pyrrole adducts showed a strong correlation with glucose indices before and after adjustment for age and estimated glomerular filtration rates. Stratified analysis showed that the medians and interquartile values of pyrrole adducts grew as glucose indices of the subgroups increased. Participants with symptoms of DSPN and sinus tachycardia presented elevated levels of plasma pyrrole adducts.

CONCLUSION

This study provides a novel link between glucose indices and the etiology of diabetic diffuse neuropathies.

Painful Diabetic Neuropathy as a Cause for Refractory Ear Pain in Type 2 Diabetic Patients

OBJECTIVE

To assess painful diabetic neuropathy (PDN) as a cause for refractory ear pain in type 2 diabetics.

DESIGN

An observational prospective case series study.

SETTING

Otolaryngology departments of tertiary referral hospitals from November 2019 to January 2021.

PATIENTS

Sixty-eight patients with type 2 diabetes with refractory ear pain of more than 1-month duration not responding to the routine analgesics.

INTERVENTION

Diagnostic intervention.

MAIN OUTCOME MEASURE

The primary outcome measure was the prevalence of painful diabetic neuropathy among different causes of ear pain in the study sample of type II diabetics with refractory ear pain with an assessment of the response of these cases to routine neuropathic pain treatment with pregabalin.

RESULTS

Fifteen out of 68 (22.1%) were diagnosed as having painful diabetic neuropathy based on the "Douleur Neuropathique en 4 Questions" (DN4) questionnaire with its mean value being 6.47±1.19. There was a highly significant improvement of the 10 items of painful diabetic neuropathy scales after 1 month of treatment ( p < 0.001 for all). There was a significant positive correlation between the Hemoglobin A1c level and duration of diabetes at one hand and intensity of pain derived from the painful diabetic neuropathy scale at the other hand ( p = 0.0002, and p = 0.032 respectively).

CONCLUSION

Painful diabetic neuropathy showed a potential correlation with refractory ear pain in type II diabetic patients with significant improvement after painful diabetic neuropathy treatment. Further studies are needed to confirm these findings.

Vibration Perception Threshold and Related Factors for Balance Assessment in Patients with Type 2 Diabetes Mellitus

Diabetic peripheral neuropathy (DPN) is a common complication of type 2 diabetes mellitus (DM). DPN causes a decrease in proprioception, which could reduce balance ability. We investigated the association of impaired vibration sense, based on vibration perception threshold (VPT), with assessments of balance and other factors affecting balance impairment and fear of falling in patients with type 2 DM. Sixty-three patients with DM aged >50 years were categorized as having normal vibration sense (NVS; n = 34) or impaired vibration sense (IVS; n = 29) according to a VPT value of 8.9 μm. The following parameters were evaluated for all patients: postural steadiness through the fall index using posturography, functional balance through the Berg Balance Scale (BBS), the Timed Up and Go test (TUG), and fear of falling through the Falls Efficacy Scale-International (FES-I). The IVS group showed a significantly greater balance impairment in fall index, BBS, and TUG, as well as greater fear of falling on the FES-I than the NVS group. The linear regression analysis showed that the fall index was associated only with the VPT, whereas BBS, TUG, and FES-I were associated with the VPT, age, and/or lower extremity muscle strength. VPT, age, and/or muscle strength were identified as predictors of balance and fear of falling in patients with type 2 DM. Therefore, along with age and lower extremity strength, the VPT can be useful for balance assessment in patients with type 2 DM.

Inflammatory biomarkers as a part of diagnosis in diabetic peripheral neuropathy

Diabetic peripheral neuropathy (DPN), a chronic neurological complication of diabetes mellitus, remains scantily addressed area of research. Many lacunae in the temporal sequence between cause and effect of DPN still remain unfilled and therefore treatment of DPN remains unsatisfactory. This is largely due to the conventional glucocentric focus to resolve the problem. This focus over hyperglycemia should be shifted to consider, chronic low grade inflammation as the major determinant in DPN. Rapidly emerging evidences from recent studies suggest that chronic low grade inflammation leads to the activation of innate immune system response, loss of insulin signaling and insulin resistance, endoplasmic reticulum stress, mitochondrial stress, leading to production of kinases like protein kinase C, mitogen activated protein kinase and jun-N-terminal kinase, pro-inflammatory cytokines and inter leukins-1b, 2, 6 and 8, tumour necrosis factor-alpha and other chemokines, leading to DPN. These biomarkers can be early predictors of DPN and therefore should be the focus of work testing their clinical utility to identify high-risk individuals as well as perhaps to target interventions. In this paper, we would like to review all the aspects of DPN, laying greater emphasis on inflammatory biomarkers as a tool for early diagnosis of DPN and the possible research approaches to address it satisfactorily.

Glycated Hemoglobin (HbA1c) as a Biomarker for Diabetic Foot Peripheral Neuropathy

BACKGROUND

Diabetic peripheral neuropathy (DPN) is known to predict foot ulceration, lower-extremity amputation and mortality. Patients with diabetes mellitus have a predisposition toward developing chronic inflammatory demyelinating polyneuropathy, and this may also facilitate the formation of diabetic foot and cutaneous impairment, which are considered one of the most serious impairments of diabetes mellitus, with a prevalence of 4-10% in this population. Biomarkers research provides opportunities for the early diagnosis of these complications for specific treatments useful to prevent amputation and, therefore, physical inability and mental disturbance. The recent literature has suggested that glycemic levels may be a novel factor in the pathogenesis of diabetic foot complications and is an important mediator of axonal dysfunction. The aim of this systematic literary review is to determine whether hemoglobin A1c (HbA1c) is a positive predictor for diabetic foot peripheral neuropathy and its complications, such as foot cutaneous impairments. There is a lack of consensus regarding the effect of glycemic variability on diabetic foot peripheral neuropathy, unlike other complications such as retinopathy, nephropathy or micro/macrovascular pathology Methods: Relevant articles were searched in the Medline database using PubMed and Scopus and relevant keywords. The primary search terms used were "glycated hemoglobin" OR "HbA1c" AND "diabetic neuropathies" AND "Foot".

RESULTS

A number of articles (336) were initially identified while searching the scientific literature regarding this topic, and 32 articles were selected and included in this review.

CONCLUSIONS

This review highlights the role of HbA1c in diabetic foot peripheral neuropathy. Biomarkers play an important role in the decision-making process, and HbA1c levels are extensively used for diabetic foot clinical outcomes and settings, but biomarker research in diabetic foot peripheral neuropathy is in its infancy and will require careful attention to a number of factors and associations, since the consequences of DPN also include neurological alterations. HbA1c is an accurate and easy-to-administer test and can be an effective biomarker in establishing the diagnosis of diabetes, but future research should focus on standardizing the HbA1c level and selecting which DPN value and its correlated complications, such as foot cutaneous impairments, are the most informative.

Therapeutic Potentials of Colocasia affinis Leaf Extract for the Alleviation of Streptozotocin-Induced Diabetes and Diabetic Complications: In vivo and in silico-Based Studies

INTRODUCTION

Hypoglycemia in diabetes mellitus (DM) correlates with hepatic impairment, nephropathy, lipid abnormalities, and oxidative stress and subsequently complicates the disease pathogenesis. Medicinal plants have been used for the management of diabetes since ancient times. In this study, we explored the potentials of Colocasia affinis (CA), a plant known to possess anti-allergic and anti-inflammatory activities, as a remedy for diabetes and related complications.

METHODS

We induced diabetes in rats using a single intraperitoneal dose (65 mg/kg) of streptozotocin (STZ). We next treated the rats with an ethanolic extract of leaves of CA to reveal its antidiabetic and organ-protective potentials. Biomarkers of diabetes, inflammation, and oxidative stress were measured using biochemical and histopathological analysis. We also performed molecular docking for three major phytochemicals (kaempferol, myricetin, and rosmarinic acid) of CA.

RESULTS

Oral administration of the CA leaves extract at 250 mg/kg and 500 mg/kg doses decreased blood glucose level significantly (p<0.05) in STZ-induced diabetic rats. The extract also considerably attenuated plasma HbA1c levels and normalized blood lipids, glycogen, alanine aminotransferase (ALT), and aspartate aminotransferase (AST). Additionally, treatment with the extract improved kidney complications by decreasing serum creatinine and blood urea nitrogen (BUN) levels. Furthermore, CA leaves extract normalized nitric oxide (NO) and advance oxidative protein products (AOPP) in diabetic rats. The extract also showed significant improvement of the antioxidant enzymes glutathione dismutase (GSH) and superoxide dismutase (SOD) at a dose of 500 mg/kg. Besides, histological investigation demonstrated attenuation of inflammation of the vital organs, including the liver and the kidney. In silico studies revealed that three major phytochemicals (kaempferol, myricetin, and rosmarinic acid) of the ethanolic extract of leaves of CA can inhibit several molecular targets of diabetes and inflammation.

CONCLUSION

Collectively, our results demonstrated the therapeutic potentials of CA for the mitigation of diabetes and diabetic complications.

Relationship Between Glycated Hemoglobin and Vibration Perception Threshold in Diabetic Peripheral Neuropathy

Foot ulcers, infections, and deformity are some of the major sources of mortality and morbidity among the diabetic population. The relationship between glycated hemoglobin (HbA1c) and diabetic peripheral neuropathy (DPN) has been well established. There is a dearth of literature on the relationship between vibration perception threshold (VPT) and HbA1c values. So, the objective of the study was to determine the strength of linear relationship between HbA1c levels and vibration perception threshold in DPN. This cross-sectional study was conducted at Kasturba Hospital, Manipal, and diabetic foot screening camps held at various parts of Udupi district. Ethical approval was obtained from the Institutional Ethics Committee, Kasturba Hospital, Manipal (IEC:281/2017). A total of 534 participants ranging from 30 to 70 years of age and were diagnosed with type 2 diabetes mellitus on medications were included in the study. Neuropathy assessment consisting of monofilament and vibration perception threshold was done using Neurotouch beta version (Yostra Labs, Bengaluru, India). HbA1c measurement was done using turbidimetric inhibition immunoassay technique (Roche Diagnostics, Mannheim, Germany). Pearson correlation coefficient showed a moderate to good correlation between HbA1c and VPT (r = .0.753, P < .001). Linear regression result has shown a significant relationship of VPT with HbA1c (4.033 [95% confidence interval = 3.67-4.39]). The present study has concluded that there is strong relationship between HbA1c values and VPT and could be a predictor for complications in the foot following DPN.

Phytate Decreases Formation of Advanced Glycation End-Products in Patients with Type II Diabetes: Randomized Crossover Trial

Myo-inositol hexaphosphate (phytate; IP6) is a natural compound that is abundant in cereals, legumes, and nuts and it has the ability to chelate metal cations. The binding of IP6 to transition metals suggests that it could be used for the treatment of metal-catalyzed protein glycation, which appears to trigger diabetes-related diseases. Our in vitro studies showed that IP6 reduced the formation of Fe3+-catalyzed advanced glycation end-products (AGEs). This led us to perform a randomized cross-over trial to investigate the impact of the daily consumption IP6 on protein glycation in patients with type 2 diabetes mellitus (T2DM; n = 33). Thus, we measured AGEs, glycated hemoglobin (HbA1c), several vascular risk factors, and urinary IP6 at baseline and at the end of the intervention period. Patients who consumed IP6 supplements for 3 months had lower levels of circulating AGEs and HbA1c than those who did not consume IP6. This is the first report to show that consumption of IP6 inhibits protein glycation in patients with T2DM. Considering that AGEs contribute to microvascular and macrovascular complications in T2DM, our data indicates that dietary supplementation with IP6 should be considered as a therapy to prevent the formation of AGEs and therefore, the development of diabetes-related diseases in patients with T2DM.

Diabetic Polyneuropathy in Type 2 Diabetes Mellitus: Inflammation, Oxidative Stress, and Mitochondrial Function

Diabetic polyneuropathy (DPN) is defined as peripheral nerve dysfunction. There are three main alterations involved in the pathologic changes of DPN: inflammation, oxidative stress, and mitochondrial dysfunction. Inflammation induces activation of nuclear factor kappa B, activator protein 1, and mitogen-activated protein kinases. Oxidative stress induced by hyperglycemia is mediated by several identified pathways: polyol, hexosamine, protein kinase C, advanced glycosylation end-products, and glycolysis. In addition, mitochondrial dysfunction accounts for most of the production of reactive oxygen and nitrosative species. These free radicals cause lipid peroxidation, protein modification, and nucleic acid damage, to finally induce axonal degeneration and segmental demyelination. The prevalence of DPN ranges from 2.4% to 78.8% worldwide, depending on the diagnostic method and the population assessed (hospital-based or outpatients). Risk factors include age, male gender, duration of diabetes, uncontrolled glycaemia, height, overweight and obesity, and insulin treatment. Several diagnostic methods have been developed, and composite scores combined with nerve conduction studies are the most reliable to identify early DPN. Treatment should be directed to improve etiologic factors besides reducing symptoms; several approaches have been evaluated to reduce neuropathic impairments and improve nerve conduction, such as oral antidiabetics, statins, and antioxidants (alpha-lipoic acid, ubiquinone, and flavonoids).