Non-invasive assessment of vibration perception and protective sensation in people with diabetes mellitus: inter- and intra-rater reliability

The accuracy of 10 g monofilament use for clinical screening of diabetes peripheral neuropathy among Indian population

OBJECTIVE

The purpose of this study was to test the diagnostic accuracy of the 10g monofilament to screen for diabetic peripheral neuropathy (DPN) in India. The study further assessed the effect of physical activity, footwear use, and occupation on the outcome.

METHODS

Non-probabilistic purposive sampling was used to recruit patients with T2DM to assess the diagnostic utility of the 10 g monofilament. 160 participants were recruited divided into 4 groups. Each group consisted of 40 participants with 20 under each category described as "Physical Worker Vs Non- physical worker" (n = 40), "Barefoot Vs Footwear" (n = 40), "Use of Slipper at Home Vs No-slippers use at home" (n = 40), "Agriculture Vs Non- agriculture" (n = 40). 10 g monofilament was used to detect the presence of protective sensation towards screening of DPN against biothesiometer (Vibration Pressure Threshold).

RESULTS

The area under the ROC (receiver operating characteristic) curve was 0.6 for identifying DPN using the 10 g monofilament. Physical work (p = 0.04), footwear (p = 0.04), slipper use at home (p = 0.02) and occupation (p = 0.02) impacted on the diagnostic utility of the 10g monofilament.

CONCLUSIONS

This study shows that the 10 g monofilament has limited accuracy for detecting DPN in the Indian population and this is further affected by occupation, socioeconomic and religious practice.

Temporal Trends in Distal Symmetric Polyneuropathy in Type 2 Diabetes: The Fremantle Diabetes Study

CONTEXT

Macrovascular outcomes in type 2 diabetes have improved over recent decades. There are scant equivalent distal symmetric polyneuropathy (DSPN) data.

OBJECTIVE

This work aimed to characterize temporal changes in DSPN prevalence and incidence rates (IRs) in community-based Australians.

METHODS

An observational study was conducted among an urban population. Participants included individuals with type 2 diabetes from the Fremantle Diabetes Study phases I (FDS1; n = 1296 recruited 1993-1996) and II (FDS2; n = 1509 recruited 2008-2011). Main outcome measures included Michigan Neuropathy Screening Instrument (MNSI) clinical grading.

RESULTS

DSPN prevalence by 8-point MNSI was 30.8% (FDS1) and 58.9% (FDS2; P < .001), and by 6-point (excluding foot appearance) and 2-point (biothesiometry alone) MNSI was 37.5% and 35.7% (P = .336), and 33.8% and 38.7% (P = .011), respectively. Given between-phase changes in appearance assessment, 8-point MNSI data were not analyzed further. In multivariable analysis, FDS2 vs FDS1 participation was associated with 6-point (odds ratio (95% CI) 0.68 (0.56-0.83); P < .001) but not 2-point (0.90 (0.74-1.11); P = .326) MNSI DSPN prevalence. Four-year DSPN IRs (95% CI) for 6-point MNSI were 13.6 (12.0-15.4) and 17.6 (15.9-19.4)/100 person-years in FDS1 and FDS2, respectively (IR ratio [IRR] 1.31 [1.12-1.55]; P < .001), and for 2-point MNSI were 13.9 (12.3-15.8) and 7.4 (16.3-8.6/100 person-years; IRR 0.53 [0.43-0.64]; P < .001). FDS2 vs FDS1 independently predicted incident DSPN for 6-point (hazard ratio [95% CI] 1.25 [1.06-1.48]; P = .009) and 2-point (0.42 [0.33-0.55]; P < .001) MNSI.

CONCLUSION

DSPN prevalence was lower or equivalent in FDS2 vs FDS1, and its incidence was greater or lower, in multivariable models depending on the MNSI features used.

Validity and Reliability of a Vibration-Based Cell Phone in Detecting Peripheral Neuropathy among Patients with a Risk of Diabetic Foot Ulcer

The aim of this study was to determine the validity and reliability of a vibration-based cell phone in detecting peripheral neuropathy among individuals with a risk of diabetic foot ulcer (DFU). The current study consisted of 3 phases: a pilot study, concurrent validity study, and interreliability study. A 128 Hz tuning fork and vibration-based cell phone using the Vibrations-Test app was compared in the primary care setting. The pilot study confirmed that the vibration-based cell phone has an adequate reliability (r > 0.70, P < .001). The concurrent validity test involved 96 participants (aged 55.78 ± 8.32 years). The Pearson correlation test found the highest correlation in the fifth metatarsal heads (r = 0.741, right feet; 0.772, left feet; P < .001). In the 4 primary care settings, the interrater reliability between nurses of the vibration-based cell phone were k = 1.000, 1.000, 1.000, and 0.720. The concurrent validity test found moderate to strong correlation results and that the interrater reliability had a strong agreement that was almost perfect. Thus, vibration-based cell phone applications can be used as screening tools for detecting neuropathy among individuals with a risk of DFU.

Wearable sensors-based postural analysis and fall risk assessment among patients with diabetic foot neuropathy

AIMS

To investigate the cross-sectional association between deep and superficial diabetic neuropathy, postural impairment assessed by wearable inertial sensors, and the risk of fall among patients with diabetic foot.

METHODS

Diabetic patients attending a University Podiatric Clinic were evaluated for the presence of deep and superficial peripheral neuropathy in sensory tests. Postural impairment was assessed using a wearable inertial sensor, and the evaluation of balance/gait and risk of fall was determined by the Tinetti Scale and Downton Index, respectively. Glycemic control was measured by glycated haemoglobin concentration and fasting glycaemia. The postural parameters measured were the anteroposterior and medio-lateral sway of the center of mass (CoM) and the sway area (area traveled by the CoM per second). The results were analyzed through a logistic regression model to assess those posture variables mostly significantly associated with neuropathy and risk of fall scales.

RESULTS

A total of 85 patients were evaluated. Spearman's rank correlation coefficients showed a strong and significant relationship (p < 0.05) between deep diabetic neuropathy assessed by Semmes-Weinstein monofilament, diapason and biothensiometer and postural alterations, whereas no significant correlations between superficial (painful sensitivity) neuropathy and the postural parameters. The sway path of the displacement along the anterior-posterior axis recorded during tests performed with eyes open and feet close together were significantly (p < 0.05) correlated with a poor glycemic (glycated haemoglobin concentration) control and each other with all diabetic neuropathy tests, fall risk scales, muscular weakness, ankle joint limitation and history of ulcers.

CONCLUSIONS

The results support the existence of a strong association between alterations of the deep somato-sensitive pathway (although depending on the tool used to measure peripheral neuropathy), glycemic control and balance impairments assessed using a wearable sensors. Wearable-based postural analysis might be part of the clinical assessment that enables the detection of balance impairments and the risk of fall in diabetic patients with diabetic peripheral neuropathy.

Peripheral Neuropathy in Diabetes Mellitus: Pathogenetic Mechanisms and Diagnostic Options

Diabetic neuropathy (DN) is one of the main microvascular complications of both type 1 and type 2 diabetes mellitus. Sometimes, this could already be present at the time of diagnosis for type 2 diabetes mellitus (T2DM), while it appears in subjects with type 1 diabetes mellitus (T1DM) almost 10 years after the onset of the disease. The impairment can involve both somatic fibers of the peripheral nervous system, with sensory-motor manifestations, as well as the autonomic system, with neurovegetative multiorgan manifestations through an impairment of sympathetic/parasympathetic conduction. It seems that, both indirectly and directly, the hyperglycemic state and oxygen delivery reduction through the vasa nervorum can determine inflammatory damage, which in turn is responsible for the alteration of the activity of the nerves. The symptoms and signs are therefore various, although symmetrical painful somatic neuropathy at the level of the lower limbs seems the most frequent manifestation. The pathophysiological aspects underlying the onset and progression of DN are not entirely clear. The purpose of this review is to shed light on the most recent discoveries in the pathophysiological and diagnostic fields concerning this complex and frequent complication of diabetes mellitus.

Factors influencing diabetes-related foot ulcer healing in Australian adults: A prospective cohort study

OBJECTIVE

Diabetes-related foot ulceration (DFU) is a common limb-threatening condition, which is complex and subsequently challenging to manage. The aim of this study was to determine the contribution of a range of clinical and social factors to the healing of diabetes-related foot ulceration in an Australian population.

RESEARCH DESIGN AND METHODS

This was a prospective cohort study of individuals with diabetes-related foot ulceration (DFU). Age, sex, medical history, medications, dietary supplementation (e.g. vitamin C intake) and smoking history were elicited at baseline. The index of relative socio-economic disadvantage (IRSD) was calculated. The Australian Eating Survey and International Physical Activity Questionnaire-short were administered. Wound history, size, grade, time to healing and infection were captured and monitored over 6 months. Logistic regression was performed to determine the relationship between healing and diet quality, toe systolic pressure, wound size at, IRSD, infection and previous amputation.

RESULTS

A total of 117 participants were included. The majority were male n = 96 (82%), socio-economically disadvantaged (mean IRSD 965, SD 60), and obese (BMI 36 kg/m² , SD 11) with a long history of diabetes (20 years, SD 11). Wounds were predominantly neuropathic (n = 85, 73%) and classified 1A (n = 63, 54%) on the University of Texas wound classification system with few infections (n = 23, 16%). Dietary supplementation was associated with 4.36 increased odds of healing (95% 1.28-14.84, p = 0.02), and greater levels of socio-economic advantage were also associated with increased odds of healing (OR 1.01, 95% CI 1.01-1.02, p = 0.03).

CONCLUSIONS

In this cohort study of predominantly neuropathic, non-infected DFU, individuals who had greater levels of socio-economic advantage had significantly greater odds of DFU healing. Diet quality was poor in most participants, with individuals taking supplementation significantly more likely to heal.

Comparison of waist-height ratio and other obesity indices in the prediction of diabetic peripheral neuropathy

Background

Waist-height ratio (WHtR) is increasingly being studied as a simple and effective measure of central obesity. Reports have shown that WHtR is a better predictor of hypertension, diabetes, and cardiovascular diseases when compared to traditional obesity indices like body mass index (BMI), waist circumference (WC), and waist-hip ratio (WHR). This study is therefore aimed at comparing WHtR with other obesity indices in the prediction of peripheral neuropathy in persons with diabetes mellitus (DM).

Methodology

One thousand and forty persons with DM were enrolled following consent. Relevant details of history were obtained, followed by physical examinations. Data were analyzed using IBM-SPSS version 23. Logistic regression was used to compare the odds ratio of obesity indices in the prediction of peripheral neuropathy. The level of significance used was p = 0.05.

Results

Logistic regression showed that WHtR had the highest odds ratio (OR) for the prediction of "probable" diabetic peripheral neuropathy (OR 9.11, 95% CI 3.07-47.97, p = 0.002), followed by WC (OR 2.01, 95% CI 1.09-4.05, p = 0.004), and BMI (OR 1.26, 95% CI 1.00-3.99, p = 0.019) after correction for age; systemic hypertension; duration of DM; control of SBP, DBP, HbA1c, FPG, and 2HrPP.

Conclusion

WHtR has the highest odds ratio in the prediction of "probable" diabetic peripheral neuropathy in both genders, followed by WC in the males and BMI in the females.

Reliability of recommended non-invasive chairside screening tests for diabetes-related peripheral neuropathy: a systematic review with meta-analyses

The objective is to determine, by systematic review, the reliability of testing methods for diagnosis of diabetes-related peripheral neuropathy (DPN) as recommended by the most recent guidelines from the International Diabetes Foundation, International Working Group on the Diabetic Foot and American Diabetes Association. Electronic searches of Cochrane Library, EBSCO Megafile Ultimate and EMBASE were performed to May 2021. Articles were included if they reported on the reliability of recommended chairside tests in diabetes cohorts. Quality appraisal was performed using a Quality Appraisal of Reliability Studies checklist and where possible, meta-analyses, with reliability reported as estimated Cohen's kappa (95% CI). Seventeen studies were eligible for inclusion. Pooled analysis found acceptable inter-rater reliability of vibration perception threshold (VPT) (κ=0.61 (0.50 to 0.73)) and ankle reflex testing (κ=0.60 (0.55 to 0.64)), but weak inter-rater reliability for pinprick (κ=0.45 (0.22 to 0.69)) and 128 Hz tuning fork (κ=0.42 (0.15 to 0.70)), though intra-rater reliability of the 128 Hz tuning fork was moderate (κ=0.54 (0.37 to 0.73)). Inter-rater reliability of the four-site monofilament was acceptable (κ=0.61 (0.45 to 0.77)). These results support the clinical use of VPT, ankle reflexes and four-site monofilament for screening and ongoing monitoring of DPN as recommended by the latest guidelines. The reliability of temperature perception, pinprick, proprioception, three-site monofilament and Ipswich touch test when performed in people with diabetes remains unclear.

Quantitative vibration perception threshold in assessing diabetic polyneuropathy: Should the cut-off value be adjusted for Chinese individuals with type 2 diabetes?

AIMS/INTRODUCTION

To examine the performance and identify the optimal threshold of vibration perception threshold (VPT) for diagnosing diabetic polyneuropathy (DPN) in a Chinese population according to multiple definitions of DPN as gold standards.

MATERIALS AND METHODS

VPT was determined in 421 Chinese individuals with type 2 diabetes, who simultaneously completed a questionnaire of neuropathic symptoms, and underwent the assessment of signs of peripheral neuropathy and electromyography tests. Three definitions of DPN (i.e., clinician-diagnosed DPN, abnormal nerve conduction and confirmed DPN) were taken as reference gold standards.

RESULTS

Vibration perception threshold was a specific measure for all three groups of DPN outcomes, with the highest specificity noted for clinician-diagnosed DPN (85.1%). The specificity for abnormal nerve conduction and confirmed DPN was 77.0 and 76.6%, respectively. The sensitivity of VPT was 67.0% for clinician-diagnosed DPN, 66.5% for abnormal nerve conduction and 67.2% for confirmed DPN. The optimal cut-off threshold for abnormal nerve conduction, as well as confirmed DPN, was VPT >14.9 V. The specificity and sensitivity of VPT >14.9 V as the cut-off value for clinician-diagnosed DPN were 85.6 and 66.2%, respectively. When taking clinician-diagnosed DPN as the gold standard, the performance of VPT for diagnosing DPN was best with an area under the curve value of 0.804.

CONCLUSIONS

VPT measured using the neurothesiometer had relatively high specificity and best performance for diagnosing DPN when clinician-diagnosed DPN rather than abnormal nerve conduction was taken as the gold standard in a Chinese population. A VPT value of ≥15 V might be equally applicable for diagnosing DPN in a Chinese population.

Integrating Tactile Feedback Technologies Into Home-Based Telerehabilitation: Opportunities and Challenges in Light of COVID-19 Pandemic

The COVID-19 pandemic has highlighted the need for advancing the development and implementation of novel means for home-based telerehabilitation in order to enable remote assessment and training for individuals with disabling conditions in need of therapy. While somatosensory input is essential for motor function, to date, most telerehabilitation therapies and technologies focus on assessing and training motor impairments, while the somatosensorial aspect is largely neglected. The integration of tactile devices into home-based rehabilitation practice has the potential to enhance the recovery of sensorimotor impairments and to promote functional gains through practice in an enriched environment with augmented tactile feedback and haptic interactions. In the current review, we outline the clinical approaches for stimulating somatosensation in home-based telerehabilitation and review the existing technologies for conveying mechanical tactile feedback (i.e., vibration, stretch, pressure, and mid-air stimulations). We focus on tactile feedback technologies that can be integrated into home-based practice due to their relatively low cost, compact size, and lightweight. The advantages and opportunities, as well as the long-term challenges and gaps with regards to implementing these technologies into home-based telerehabilitation, are discussed.

Foot health of Aboriginal and Torres Strait Islander Peoples in regional and rural NSW, Australia

BACKGROUND

Foot health of Aboriginal and Torres Strait Islander Australians' has not been established. Additionally, studies have shown that there is a lack of engagement of this population with general preventive foot care services. The aim of this study was to establish foot health in Aboriginal and Torres Strait Islander people attending two recently developed, culturally safe podiatry services in rural and regional New South Wales (NSW), Australia. Secondarily the relationship between self-perceived foot health and some medical and demographic characteristics was investigated.

METHODS

This descriptive cross-sectional study included participants attending the culturally safe foot health care services managed by the University of Newcastle on the Central Coast or in Wellington, both located in NSW, Australia. At the consultation, participants completed the Foot Health Status Questionnaire (FHSQ) with the assistance of an Aboriginal health care worker, underwent basic vascular and neurological screening, and podiatric treatment.

RESULTS

A total of 111 Aboriginal and Torres Strait Islander Australians (48 from the Central Coast, and 63 from Wellington) were included. FHSQ scores for pain (75.7 ± 26.8), function (80.2 ± 25.2), footwear (53.9 ± 33.4), and general foot health (62.0 ± 30.9) were generally good, but below the optimal score of 100. The presence of diabetes (n = 39 of 111 participants or 35.1%) was associated with lower levels of self-perceived foot function (r = - 0.20, n = 107, p = 0.04).

CONCLUSION

We found that community-based foot health care services that are culturally safe are utilised by Aboriginal and Torres Strait Islander Peoples not currently at high risk of foot complications. This supports the use of culturally safe foot care services to improve engagement with preventative foot care. Future research should continue to be driven by Aboriginal and Torres Strait Islander Peoples and investigate ways to implement additional screening measures and undertake prospective evaluation of the impact of such services on health related outcomes in these communities.