Vibration Perception Threshold Testing Research Articles

Risk factors for peripheral artery disease and diabetic peripheral neuropathy among patients with type 2 diabetes

AimsTo investigate the prevalence of peripheral artery disease (PAD) and diabetic peripheral neuropathy (DPN) and the associated risk factors among Chinese patients with type 2 diabetes mellitus. MethodsA cross-sectional study was conducted using data between November 1, 2018, and December 31, 2022. PAD was defined as ABI ≤ 0.9. DPN diagnosis involved specialized physician assessments using questionnaires and vibration perception threshold tests. Logistic regression analysis was used to identify related factors. We also evaluated the association between the clustering of risk factors and disease incidence. ResultsThe study population comprised 13,315 patients (mean age: 63.3 years). 4.9 % of the patients had PAD and 43.9 % had DPN. Multivariate regression analysis revealed advanced age, smoking, hypertension, coronary heart disease, dyslipidemia, elevated HbA1c, and uric acid levels as independent risk factors for PAD. For DPN, independent risk factors included advanced age, female gender, hypertension, coronary heart disease, elevated total cholesterol, triglycerides, lipoprotein(a), fasting plasma glucose, HbA1c, alkaline phosphatase, cystatin C, albumin-to-creatinine ratio, and elevated homocysteine levels, whereas apolipoprotein A was a protective factor. The clustering of risk factors was prevalent and associated with higher disease risk. ConclusionsOur study contributed to identifying high-risk individuals and improving lower limb health among diabetic individuals.

A hand-held electro-mechanical exciter for multi-frequency peripheral neuropathy assessment

Diabetes is becoming alarmingly common worldwide and is associated with long-term complications. One of the major and common complications of the disease is peripheral neuropathy, which causes loss of sensation in the patient's limbs due to the degeneration of sensory nerves. Loss of sensation often allows injuries to get unnoticed, which increases the risk of infections that may lead to ulcers and amputation. Several tests are used as part of peripheral neuropathy screening, one of which is the vibration perception threshold (VPT) test. Most of the existing instruments for VPT testing apply a stimulus at a single frequency while gradually increasing the vibration acceleration until the stimulus is felt and reported by the subject. Nevertheless, recent studies have shown that performing VPT at several frequencies offers a comprehensive VPT assessment. Moreover, the literature indicates that VPT evaluation is affected by excessive pressure that may be applied by the operator while the vibrators head is in contact with the skin. In this work, we describe the design of a hand-held exciter instrument capable of applying multifrequency stimuli in the range 4 Hz 500 Hz and that prevents excessive pressure from being applied by the operator to the subjects skin.

Assessing the vibration perception threshold in a community sample of adult Ghanaians.

The vibration perception threshold (VPT) helps evaluate human somatosensory function and diagnose peripheral neuropathy. To optimize its use as a primary neurologic tool, it is imperative to establish its typical values in healthy subjects and assess the factors affecting its variability in an individual to ensure consistency in its application. Demographic data and a brief medical history were collected from 391 non-diabetic adults aged 30-80 at Kpone-on-Sea in Ghana. The VPT was measured at the tip of the big toe, the medial malleolus, the tip of the middle finger, and the head of the ulna of each participant using a Horwell Neurothesiometer. The variability of VPT was assessed vis-à-vis the following factors: gender, age, fasting plasma sugar and body mass index. The mean age of participants was 48.4 ± 0.7 years, and the female-to-male ratio was 1.46. The overall VPT values ranged from 5.74 ± 0.14 volts to 8.55 ± 0.18 volts in the lower limbs and 3.61 ± 0.06 volts to 5.00 ± 0.08 volts in the upper limbs. Age was found to be the only factor that could predict VPT for both the lower and upper limbs (P < 0.001). One-Way Analysis of Variance with Tukey's posthoc showed that the VPT in the feet was significantly higher than that in the hands. Generally, the VPT was high on proximal sites and low on distal sites indicating that the vibration sensation increased from proximal to distal direction. Therefore, distal areas should be used for VPT testing with a Neurothesiomer. Age was found to be the only factor that affected VPT variability. Hence, the practical application of VPT will require age-specific reference ranges to cater for older adults.

Early detection of diabetic peripheral neuropathy using EMLA-induced skin wrinkling

Background &amp; Objective: Screening for early diabetic peripheral neuropathy (DN) is essential for foot ulcer prevention. The Semmes–Weinstein monofilament (SWMF) is commonly used to detect DN in Thailand. However, SWMF interpretation requires patient participation, which is susceptible to risk of error in patients with impaired cognitive function or uncooperative patients. In contrast, stimulated skin wrinkling (SSW) can be interpreted by trained investigators, which is more appropriate. This study aimed to investigate the utility of SSW using a eutectic mixture of local anesthetic (SSW-EMLA) for early DN diagnosis. Methods: This cross-sectional study, recruited 102 patients with diabetes (DM group), 33 with diabetes with foot ulcer (DN control group), and 30 without diabetes (non-DN control group) from the Faculty of Medicine, Vajira Hospital, Navamindradhiraj University, Thailand, from February 3, 2021 to November 30, 2021. SSW was conducted by applying EMLA on the tips of the 2nd, 3rd, and 4th fingers of both hands. SWMF, sensory perception of pain (SPP), vibration perception threshold (VPT), joint position sense (JPS), and deep tendon reflexes (DTR) were also evaluated on the same day. Results: The Interrater agreement of two investigators for SSW-EMLA was high with intraclass correlation coefficients of 0.87 (0.824–0.904) for the right hand and 0.874 (0.830–0.907) for the left hand. The kappa coefficients of agreement of SSW-EMLA for SPP, SWMF, VPT, JPS, and DTR testing were 0.411, 0.478, 0.714, 0.444, and 0.681, respectively. The sensitivity and specificity of SSW-EMLA testing for DN detection were 83.3%, was 85.7%, respectively. Conclusion: The SSW-EMLA test can be considered as an alternative method for DN detection, due to its noninvasiveness, inexpensiveness (50THB), being a simple procedure, high sensitivity and specificity, and acceptable rater variation.

Subthreshold white noise vibration alters trembling sway in older adults

BackgroundSomatosensory deficit is a significant contributor to falls in older adults. Stochastic resonance has shown promise in recent studies of somatosensation-based balance disorders, improving many measures of stability both inside and outside of the clinic. However, our understanding of this effect from a physiological perspective is poorly understood. Therefore, the primary goal of this study is to explore the influence of subthreshold vibratory stimulation on sway under the rambling-trembling framework. Methods10 Healthy older adults (60–65 years) volunteered to participate in this study. Each participant underwent two randomized testing sessions on separate days, one experimental and one placebo. During each session, the participants' baseline sway was captured during one 90-s quiet standing trial. Their sensation threshold was then captured using a custom vibratory mat and 4–2-1 vibration perception threshold test. Finally, participants completed another 90-s quiet standing trial while the vibratory mat vibrated at 90% of their measured threshold (if experimental) or with the mat off (if placebo). While they completed these trials, an AMTI force plate collected force and moment data in the anteroposterior (AP) and mediolateral (ML), from which the center of pressure (COP), rambling (RM), and trembling (TR) time series were calculated. From each of these time series, range, variability (root-mean-square), and predictability (sample entropy) were extracted. One-tailed paired t-tests were used to compare baseline and during-vibration measures. ResultsNo significant differences were found during the placebo session. For the experimental session, significant increases were found in AP TR range, ML TR RMS, AP COP predictability, and AP & ML TR predictability. The TR time series was particularly sensitive to vibration, suggesting a strong influence on peripheral/spinal mechanisms of postural control. SignificanceThough it is unclear whether observed effects are indicative of “improvements” or not, it does suggest that there was a measurable effect of subthreshold vibration on sway. This knowledge should be utilized in future studies of stochastic resonance, potentially acting as a mode of customization, tailoring vibration location, duration, magnitude, and frequency content to achieve the desired effect. One day, this work may aid in our ability to treat somatosensation-based balance deficits, ultimately reducing the incidence and severity of falls in older adults.

486-P: Reduced Serum Netrin-1 Levels Correlate with Corneal Nerve Fiber Loss in Diabetic Neuropathy

Objective: Deficiency of endogenous neurotropic factors are implicated in diabetic neuropathy (DN). While Netrin-1, a neurotropic factor, is downregulated in type 2 diabetes, its involvement in Diabetic Neuropathy (DN) is yet to be reported. While corneal confocal microscopy (CCM) is a sensitive, in-vivo, non-invasive technique for detection of DN at its earliest stages, the association between CCM parameters and serum Netrin-1 levels has not been reported before. The present study looked at serum netrin levels in populations with type 2 diabetes with or without neuropathy, using CCM as the gold standard. Methods: Sixty subjects with type 2 diabetes (DN- 30, DN+ 30)] were stratified using DN4Q and Vibration perception Threshold Test (VPT). Cornea was assessed using CCM. Serum Netrin-1 level was measured by ELISA. Data compared 27 healthy controls were also studied. Results: There was a significant reduction in corneal nerve fibre density (CNFD), branch density (CNBD), and fibre length (CNFL) in T2D. DN was associated with a greater reduction in all CCM parameters compared to those with type 2 diabetes but no DN (p&amp;lt;0.05). There was a progressive decline in the mean serum netrin-1 level from healthy controls to T2D DN- to T2D DN+ (Control vs T2D, p&amp;lt;0.05; T2D DN- vs DN+, p&amp;lt;0.01)]. Netrin-1 correlated only with CNBD in T2D DN- group, (p=0.02). While ROC analysis showed CNFD, CNBD and CNFL to predict DN in 55.6%, 57.1% and 62.1% respectively, Netrin-1 alone predicted DN in 63.3%. CNBD and CNFL correlated with Netrin-1 (p=0.04 and p=0.01) in T2D DN+ group. Conclusion: Serum netrin-1 levels declined progressively from controls to T2D to T2D with DN; netrin-1 levels correlated significantly with the CCM parameters. Serum Netrin-1 levels showed a significant positive correlation with CNBD in type 2 diabetes (DN- or DN+). A strong correlation was seen between CNFL and netrin-1 levels in more advanced diabetic neuropathy (abnormal VPT). The results of our pilot study need validation in larger populations. Disclosure A.Mondal: None. C.Bose: None. S.Pramanik: None. A.Mukherjee: None. B.Mukherjee: None. S.Mukhopadhyay: None. Funding Research Society for the Study of Diabetes in India

Objective assessment of mobility among adults with diabetes and end-stage renal disease using walking aid: A cross-sectional cohort study

BackgroundThis cross-sectional study aimed to compare physical activity levels, plantar sensation, and fear of falling between individuals with diabetes undergoing hemodialysis, with or without walking aids. MethodsSixty-four participants were recruited, with 37 not using walking aids (age = 65.8 ± 0.7 years, 46% female) and 27 using walking aids (age = 69.2 ± 1.2 years, 63% female). Physical activity was measured using validated pendant sensors over two consecutive days. Concern for falling and plantar numbness were assessed using the Falls Efficacy Scale-International and vibration perception threshold test, respectively. FindingsParticipants using walking aids exhibited a greater fear of falling (84% vs. 38%, p < 0.01) and fewer walking bouts (p < 0.01, d = 0.67) and stand-to-walk transitions (p < 0.01, d = 0.72) compared to those not using walking aids. The number of walking bouts was negatively correlated with concern for falling scores (ρ = −0.35, p = 0.034) and vibration perception threshold (R = −0.411, p = 0.012) among individuals not using walking aids. However, these correlations were not significant among those using the walking aid. There was no significant group difference in active behavior (walking + standing %) and sedentary behavior (sitting + lying %). InterpretationThose undergoing hemodialysis often lead sedentary lives, with mobility affected by fear of falling and plantar numbness. Using walking aids can help, but it doesn't guarantee more walking. A combined psychosocial and physical therapy approach is key for managing fall concerns and improving mobility.

IDF21-0461 Prevalence of Charcot Arthropathy in patients with Type 2 Diabetes and severe peripheral neuropathy

Background: Charcot arthropathy (CA) of the foot, an infrequent neuromusculoskeletal sequelae of diabetes, progressively ends up in varying degrees of destruction and deformity of the foot and ankle. With recent advances in DM medicine which inevitably increase the life expectancy of the patients, podiatrists are likely to come across more number of DM patients with foot complications such as CA. The prevalence of CA is hardly reported in Indian population. Therefore, an effort has been made to study the prevalence of CA in DM patients who are at risk to develop CA in Indian population. Aim: The main aim of this study was to evaluate the prevalence of CA in patients with type 2 diabetes mellitus and severe peripheral neuropathy (T2DMPN), belonging to Indian population amongst whom type 2 diabetes is on the rise in alarming proportions. Method: This was a retrospective study where a through review of medical records of all patients both inpatient and outpatient who performed an objective vibration perception threshold (VPT) test was carried out. Only known cases of diabetic neuropathy were considered. After careful scrutiny of medical records, patients with other causes for neuropathy were excluded from the study. out of 3387 medical records of patients evaluated those of 1475, T2DMPN patients over 50 years of age were selected and were thoroughly reviewed for CA. CA was diagnosed on the basis of clinical features and/or radiological investigations (plain radiographs and/or nuclear scan and/or magnetic resonance imaging [MRI]) or a combination of these. Results: Analysis of medical records of these 1475 patients for clinical and radiological features of CA showed that 144 (9.8%) patients had CA. The mean age of patients diagnosed with CA was 63 ± 8.36 years, and mean duration of DM for CA to develop was 18.01 ± 8.23 years. About 62.5% of the patients were male and 37.5% female. Bilateral presentation of CA was observed in 20.8% of patients. Among the 141 records assessed, 19 (13.5%) patients had ABI index values <0.9 and were taken positive for PAD. One hundred and two (72.3%) had ABI index values between 0.9 and 1.4 and were considered to have good blood flow in the lower limb. Twenty (14.2%) had values >1.4 and were considered as cases with noncompressible blood vessels. Multiple sites of the foot were affected in 48.6% of patients and belonged to type 4 classification of Brodsky. Discussion: In the present study conducted on T2DMPN, the prevalence of CA was found to be high (9.8%). This may be due to the fact that we selected a population at high risk to develop CA. Clinicians should be very alert when dealing with such high-risk patients and should screen them for CA changes as part of their routine check-up. In contrary to what is reported in general in literature, multiple areas of the foot were affected in the majority of population followed by midfoot.

A Comparative Study of Sensory and Motor Peripheral Nerve Functions in Elderly Patients of Diabetes Mellitus and Non-Diabetic Controls in a Tertiary Care Hospital

Introduction: In elderly diabetics, peripheral neuropathy is a significant cause of morbidity and physical disability. Diabetes Mellitus, and its chronic complications like peripheral neuropathy have been instrumental in contributing to the physical decline in the elderly. However, objective assessment of physical ability in elderly diabetics and devising their correlation to reduced peripheral nerve functions has been a hitherto uncharted territory. This study aims at evaluating the peripheral nerve functions in elderly diabetics. This study hypothesizes that peripheral nerve functions were significantly reduced in elderly diabetics in comparison to elderly nondiabetics. Materials and Method: Relevant history, prescriptions and laboratory reports were collected from the study participants. Sensory functions were tested by 10g Semmes-Weinstein Monofilament Test and Vibration Perception Threshold (VPT) was tested by handheld biothesiometer. Motor functions were tested by the Compound Muscle Action Potential and Nerve Conduction Velocity (CMAP and NCV respectively) for the peroneal nerve (preferably of right side). Fisher exact test has been applied barring the parameters for nerve function with respect to Monofilament and VPT. For Monofilament and VPT, Z statistic has been used to test the differences in proportion. Results: Most of the diabetic patients were overweight. NCV and CMAP were significantly reduced in diabetics. Mean NCV in diabetic group was 37.81 m/s as compared to 42.08 in non-diabetic. Mean CMAP in diabetics was 2.55 mV as compared to 3.21 mV in non-diabetic. Our study showed that number of participants with impaired VPT and monofilament test was higher in diabetics than non-diabetics. Conclusion: Diabetic patients are more prone to develop peripheral neuropathy. Assessment of the clinical homologue of these pathological processes is the first step in implementing the appropriate type of intervention. Treatment should be individualized to take into account specific manifestations and the underlying pathogenesis of each patient's unique clinical presentation. Keywords: Diabetes Mellitus, Nerve Function, Peripheral Neuropathy.

NEURO TOUCH: A novel digital device for assessment and screening of peripheral neuropathy

BackgroundMost of the patients suffering from diabetes develop Sensory neuropathy which proceeds with development of painful neuropathy. This can lead to formation of ulcers in later stages. Currently, available Quantitative Sensory Testing (QST) devices take more time to perform and are expensive. NEURO TOUCH is such device which combines four parameters of QST in one unit. Its portable, battery operated and handy device with real time display of results along with data storage and data transfer facility. It can perform tactile sensation threshold, vibration and thermal testing threshold along with skin temperature measurement. This study was undertaken to establish the diagnostic validity, reproducibility and repeatability for early detection of peripheral neuropathy. MethodsA total of 317 subjects were recruited for QST assessment with NEURO TOUCH; Tactile threshold sensation, vibration perception and thermal threshold testing along with skin temperature. A subset of 30 subjects in each group were considered for repeatability and reproducibility test. ResultsThe mean difference for vibration perception threshold was 0.6 when compared with gold standard device. Regarding the cold and warm perception threshold the mean difference was 1.1 and 2 °C respectively when compared with gold standard device. For skin temperature measures there was a mean difference of 1.2 °C with respect to standard device. ConclusionsThe NEURO TOUCH device was easy-to-use, compact and provided an efficient multimodality approach which can help for screening of peripheral neuropathy patients with type 2 diabetes.

Acute Effects of a Whole Body Vibration Session on the Vibration Perception Threshold in Patients with Type 2 Diabetes Mellitus.

Background: Type 2 Diabetes Mellitus (T2DM) is a chronic disease that affects millions of people, and according to the International Diabetes Federation, 46.5% of people have undiagnosed diabetes. One of the most common complications of diabetes mellitus is loss of peripheral sensation. Whole Body Vibration (WBV) is a therapy, and it would be interesting to know if it can be considered as a training method to improve the Vibration Perception Threshold (VPT). The aim of the study is to verify whether there are really acute effects on the VPT after a WBV training session in people with T2DM. Methods: Ninety people with T2DM (56 men and 34 women) were randomly allocated to two groups: the WBV group and the placebo group. The ninety subjects went through a VPT training test before receiving the assigned intervention, and they performed the VPT test using the Vibratron II device. Results: After one session of WBV, an increase of the VPT in the WBV group was found, with respect to the placebo group. Conclusions: Vibration perception threshold is increased after a WBV training session in people with T2DM, compared to a placebo group.

T13. CORNEAL CONFOCAL MICROSCOPY DETECTS NEURAL CHANGES IN SCHIZOPHRENIA

BackgroundA combination of neurodevelopmental and degenerative neural changes are likely to underpin positive and negative symptoms in schizophrenia. However, there are currently no validated biomarkers to accurately quantify the extent of neural changes in schizophrenia.Corneal confocal microscopy (CCM) is a non-invasive ophthalmic imaging technique that has been used to demonstrate in vivo corneal nerve fiber abnormalities in a range of peripheral neuropathies and central neurodegenerative disorders including Parkinson’s disease, multiple sclerosis and dementia.We wished to test the hypothesis that corneal nerve abnormalities occur in patients with schizophrenia, particularly those with negative symptoms and cognitive impairment.MethodsPatients with DSM-V schizophrenia without other causes of peripheral neuropathy other than metabolic syndrome underwent assessment of clinical ratings (Positive and Negative Symptoms Scale (PANSS), cognitive function (Montreal Cognitive Assessment (MOCA) and Corneal confocal microscopy (CCM), vibration perception threshold (VPT) and sudomotor function testing.Healthy controls underwent the same assessments apart from PANSS.Results55 subjects without (n=38) and with schizophrenia (n=17) with comparable mean age (35.7±8.5 vs 35.6±12.2, P=0.96) were studied.Patients with schizophrenia had significantly higher body weight (93.9±25.5 vs 77.1±10.1, P=0.02) and lower Low Density Lipoproteins (2.6±1.0 vs 3.4±0.7, P=0.02) compared with healthy controls.The proportion of gender, systolic and diastolic blood pressure, HbA1c, cholesterol, triglyceride and High Density Lipoproteins were comparable between the two groups.Patients with schizophrenia had significantly lower corneal nerve fibre density (CNFD, fibers/mm2) (35.6±6.5 vs 23.5±7.8, p<0.0001), branch density (CNBD, branches/mm2) (98.1±30.6 vs 34.4±26.9, p<0.0001), and fibre length (CNFL, mm/mm2) (24.2±3.9 vs 14.3±4.7, p<0.0001) compared with healthy controls but no difference in peripheral neuropathy assessed by VPT and sudomotor function testing.The area under the Receiver Operating Characteristic Curve (95% CI) of CNFD, CNBD, CNFL to distinguish patients with schizophrenia from healthy controls were 87.0% (76.8–98.2%), 93.2% (84.2–102.3%), 93.2% (84.4–102.1%), respectively.DiscussionThese preliminary results:support the hypothesis that corneal nerve abnormalities occur in schizophrenia;corneal confocal microscopy has high diagnostic capability to distinguish subjects with schizophrenia from healthy controls;provide evidence to support the potential application of corneal confocal microscopy as a non-invasive technique to detect neural change in schizophrenia.

Tear biomarkers and corneal sensitivity as an indicator of neuropathy in type 2 diabetes

AimsExplore potential of 31 tear biomarkers involved in screening for diabetic peripheral neuropathy (DPN). Assess the utility of aesthesiometry for measuring corneal damage in DPN and determine optimal cutoff point for detecting DPN. MethodsScreening test pilot study recruited 90 participants from a tertiary hospital in Lima, Peru. Participants were grouped by diabetes and neuropathy status. Tears collected on Schirmer strips, and proteins measured by both ELISA and multiplex-bead assay. Corneal sensitivity was measured by aesthesiometry, and DPN by vibration perception threshold testing. ResultsThere were 89 participants included in the analysis. The mean age was 55.7 ± 1.46, and 58.4% were female. MMP-9 and TGF-alpha concentrations were higher in participants with DPN versus diabetes alone, though not significant. Aesthesiometry was decreased in individuals with DPN when compared to participants with diabetes alone (p < 0.01) and normal controls (p < 0.01). Optimal cutoff point for aesthesiometry was found to be 5.8 cm, with 79% sensitivity and 75% specificity. ConclusionsTears are an insufficient standalone tool for detecting DPN based on the biomarkers analyzed. Aesthesiometry is a simple, inexpensive, and accurate method to assess corneal damage associated with moderate-severe DPN, and its integration into screening practices has potential to improve detection of DPN in poor-resource settings.

Sensor-based systems for early detection of dementia (SENDA): a study protocol for a prospective cohort sequential study

BackgroundDementia and cognitive decline are serious social and economic burdens. An increase in the population of older people, as well as longer lifespans mean that numbers of dementia cases are exponentially rising. Neuropathological changes associated with dementia are thought to appear before the clinical manifestation of cognitive symptoms, i.e., memory impairments. Further, some older adults (OA) experience cognitive decline before it can be objectively diagnosed. For optimal care of these patients, it is necessary to detect cognitive decline and dementia at an early stage. In this vein, motor, sensory, and neurophysiological declines could be promising factors if found to be present before the onset of cognitive impairment. Hence, the objective of the SENDA study is to develop a multi-dimensional sensor-based instrument that allows early detection of cognitive decline or dementia in OA with the help of cognitive, sensory, motor, and neurophysiological parameters before its clinical manifestation.Methods/designIn the cohort sequential study, participants are assigned to one of three study groups depending on their cognitive status: 1. cognitively healthy individuals (CHI), 2. subjectively cognitively impaired persons (SCI), or 3. (possible) mildly cognitively impaired persons (pMCI, MCI). All groups take part in the same cognitive (e.g., executive function tests), motor (e.g., gait analyses, balance tests), sensory (e.g., vibration perception threshold test, proprioception tests), and neurophysiological (e.g., electroencephalograms) measurements. Depending on the time at which participants are included into the study, all measurements are repeated up to four times in intervals of 8 months within 3 years to identify associations with cognitive changes over time.DiscussionThis study aims to detect possible motor, sensory, neurophysiological, and cognitive predictors to develop an early screening tool for dementia and its pre-stages in OA. Thus, affected persons could receive optimal health care at an earlier time point to maintain their health resources.Trial statusThe study is ongoing. The recruitment of participants will be continued until May 2020.

Test-Retest Reliability of Vibration Perception Threshold Test in People with Type 2 Diabetes Mellitus.

Background: Diabetes mellitus is a chronic disease characterized by fasting hyperglycemia. It affects approximately 415 million people worldwide and involves a variety of complications. One of them is the loss of sensitivity to peripheral vibration. Objective: Our study aims to discover the test-retest reliability of a procedure for assessing vibration sensitivity in people with type 2 diabetes mellitus. Methodology: 90 people with type 2 diabetes mellitus (56 men and 34 women) performed the vibration perception threshold (VPT) test using the Vibratron II device. A re-test was completed seven days after the first reading. Results: The relative reliability of the VPT test result is excellent (intraclass correlation coefficient = 0.96). The same applies to gender and obesity subgroups. Regarding absolute reliability, the standard error of measurement is 8.99%, and the small real difference is 24.94%. Conclusions: The relative and absolute reliability results of the vibration perception threshold in people with type 2 diabetes mellitus offer excellent results.

The Semmes -Weinstein monofilament examination as a single effective screening tool in the evaluation of diabetic peripheral neuropathy when compared to vibration perception threshold

Background: Diabetic peripheral neuropathy (DPN) leads to foot ulcers and non-traumatic amputation, which is a major cause for morbidity and disability in India. At present, no precise pharmacological agent has confirmed efficacy in preventing disease progression or reversing neuropathy symptoms. Clinically, it is crucial to find an effective screening tool for diagnosing DPN. Although vibration perception threshold (VPT) testing and Semmes-Weinstein monofilament examination (SWME) are considered as combined diagnostic tools to diagnose DPN, a single effective screening method to identify DPN is quite unavailable in India. Aim and Objective: This study aimed to evaluate the usefulness of the SWME in DPN when compared to VPT. Materials and Methods: Fifty control subjects and 50 DPN subjects aged between 30 and 70 years were included in the study. The anthropometric parameters, fasting blood sugar (FBS), duration of diabetes mellitus, VPT, and the SWME were recorded. Results: There was a significant difference in body mass index, FBS, VPT, and SWME in DPN subjects (P < 0.0001) when compared with control subjects. The increased duration of DPN increases the VPT (0.805) values and decreases the SWME (−0.488) values. In the kappa test, the measure of agreement between SWME and VPT was significant (0.960), meaning both tests are equally effective in screening DPN subjects. Conclusion: The present findings show that SWME can be used as a single effective screening tool in diagnosing DPN when compared with VPT. This can reduce the risk of ulceration and lower extremity amputation in DPN subjects at the earliest.

Choosing a Vibratory Test to Pair With Semmes Weinstein Monofilament Testing for Evaluating Lower Extremity Sensation in Patients With Diabetes: A Comparison of Three Vibratory Methodologies.

Numerous guidelines recommend pairing Semmes-Weinstein monofilament (SWM) testing with a secondary clinical test when screening for diabetic peripheral neuropathy, yet time is very limited in clinical practice. This study compared the time to complete and the diagnostic agreement of three vibratory sensation tests. Sixty-five individuals (42% male; aged: 61 ± 12 years) were recruited. A single investigator administered the following tests bilaterally: 10-site SWM, traditional tuning fork (TTF), electronic tuning fork (ETF), and vibration perception threshold (VPT) via biothesiometer. Times to physically administer the tests were compared with a one-way repeated measures ANOVA. Cochran's Q test was used to compare the varied tests' diagnostic agreement. The ANOVA indicated there were significant (P < .001, partial eta squared = .442) differences in time to complete the varied tests. Sidak post hoc comparisons indicated the VPT (21.2 ± 14.3) testing took an intermediate time to complete, while the ETF (9.7 ± 6.5) and TTF (10.1 ± 7.5) tests took the least amount of time, and the SWM (28.6 ± 8.4) test took the longest time. There were also numerous significant differences (P ≤ .001) between the different tests in regards to neuropathy diagnoses. Tuning fork methods required 11 seconds less to administer than VPT testing. Although that may seem trivial, it is worth noting peripheral neuropathy screening often fails to occur in the precious few minutes clinicians are allotted per patient. Considering ETF's intrinsic control of stimulus amplitude and its ease of use with an embedded timer, the ETF is recommended over the TTF. Clinicians should also be mindful that different tests yield different diagnostic conclusions.

Using wearables to screen motor performance deterioration because of cancer and chemotherapy-induced peripheral neuropathy (CIPN) in adults - Toward an early diagnosis of CIPN.

An essential component for optimizing quality of life in adults with cancer is determining the degree to which therapy may negatively impact motor-performance, so that patients can maintain their quality of life and independence. This study examined whether instrumented gait and balance could determine the magnitude of deterioration in motor-performance from chemotherapy-induced peripheral neuropathy (CIPN). We recruited 84 adults with cancer (age = 71.1 ± 9.7 years old, BMI = 26.8 ± 6.2 kg/m2, gender = 56%female) and 57 age-matched non-cancer patients (age = 69.5 ± 9.8 years old, BMI = 27.1 ± 6.0 kg/m2, gender = 79%female). Based on clinical screening, the group with cancer was classified into two groups: participants with CIPN (CIPN+) and without CIPN (CIPN-). Gait and balance were quantified using validated wearables. The Vibration Perception Threshold (VPT) test was used to stratify the CIPN+ group into mild (Mild-CIPN) and severe (Severe-CIPN) subgroups. All gait and balance parameters were deteriorated in the group with cancer compared to non-cancer group with the largest effects observed for stride-time (11%, Cohen's effect size d = 1.00, p < 0.001) and eyes-closed ankle sway (94%, d = 0.49, p = 0.001). The same trend was observed when the Severe-CIPN subgroup was compared to the Mild-CIPN. VPT correlates significantly with motor deterioration, with the largest correlation found in stride-time (Rho = 0.37, p = 0.007). Severe-CIPN subjects were significantly older and overall had more deterioration in the majority of motor-performance parameters after adjusting for age (p < 0.050). These results confirmed the negative impact of CIPN on motor-performance with the largest effects on ankle stability and stride-time. VPT is a predictor of motor deterioration and may be used to determine the severity of CIPN symptom.

Age as an Independent Risk Factor for Diabetic Peripheral Neuropathy in Chinese Patients with Type 2 Diabetes.

Type 2 diabetes mellitus (T2DM) is more prevalent in aging populations. Older adults with diabetes have higher rates of macro and micro vascular complications. Our study assessed whether age is an independent factor for both large and small nerve dysfunctions in Chinese patients with T2DM. This cross-sectional study involved a total of 950 patients with type 2 diabetes (mean age: 60.01±12.30 years). Diabetic peripheral neuropathy (DPN) was assessed according to clinical symptoms and physical examinations by using neuropathy symptom score (NSS), the neuropathy disability score (NDS), Michigan Neuropathy Screening Instrument (MNSI score), vibration perception threshold (VPT) and SUDOSCAN test. By using independent logistic regression model, we showed that age was an independent risk factor of DPN (odds ratio [OR] = 1.036, 95% confidence interval [CI] 1.018-1.054, P< 0.01). T2DM patients over 71 years had a higher risk of DPN determined by using NSS/NDS (OR= 2.087; 95% CI 1.112-3.918; P <0.05), MNSI (OR=1.922; 95% CI 1.136-3.252; P<0.05), VPT (OR=3.452; 95%CI 1.052-11.332; P<0.05) and SUDOSCAN (OR=1.922; 95%CI 1.136-3.252; P<0.05) as diagnostic criteria respectively. The results of spline analysis showed a non-linearly positive association between age and OR of DPN. Individuals with 40, 50, 60, and 70 years old had LnOR of 1.22 (95%CI: 0.44- 2.00), 1.79(95%CI: 0.67- 2.91), 2.29 (95% CI: 0.98- 3.59), and 2.67(95% CI: 1.38-3.96) in DPN risk compared to T2DM patients with 19 years old, respectively. All of the above results in our study suggested age as an independent risk factor for the development of diabetic neuropathy in T2DM patients is significantly associated with the occurrence of both small and large nerve dysfunction, independent of other risk factors.

Preserved Expression of Skin Neurotrophic Factors in Advanced Diabetic Neuropathy Does Not Lead to Neural Regeneration despite Pancreas and Kidney Transplantation.

Diabetic peripheral neuropathy (DPN) is a common complication of diabetes with potential severe consequences. Its pathogenesis involves hyperglycemia-linked mechanisms, which may include changes in the expression of neurotrophic growth factors. We analyzed the expression of 29 factors potentially related to nerve degeneration and regeneration in skin biopsies from 13 type 1 diabetic pancreas and kidney recipients with severe DPN including severe depletion of intraepidermal nerve fibers (IENF) in lower limb skin biopsies (group Tx1 1st examination). The investigation was repeated after a median 28-month period of normoglycemia achieved by pancreas transplantation (group Tx1 2nd examination). The same tests were performed in 13 stable normoglycemic pancreas and kidney recipients 6–12 years posttransplantation (group Tx2), in 12 matched healthy controls (group HC), and in 12 type 1 diabetic subjects without severe DPN (group DM). Compared to DM and HC groups, we found a significantly higher (p < 0.05–0.001) expression of NGF (nerve growth factor), NGFR (NGF receptor), NTRK1 (neurotrophic receptor tyrosine kinase 1), GDNF (glial cell-derived neurotrophic factor), GFRA1 (GDNF family receptor alpha 1), and GFAP (glial fibrillary acidic protein) in both transplant groups (Tx1 and Tx2). Enhanced expression of these factors was not normalized following the median 28-month period of normoglycemia (Tx1 2nd examination) and negatively correlated with IENF density and with electrophysiological indices of DPN (vibration perception threshold, electromyography, and autonomic tests). In contrast to our expectation, the expression of most of 29 selected factors related to neural regeneration was comparable in subjects with severe peripheral nerve fiber depletion and healthy controls and the expression of six factors was significantly upregulated. These findings may be important for better understanding the pathophysiology of nerve regeneration and for the development of intervention strategies.