Declining Skeletal Muscle Function in Diabetic Peripheral Neuropathy

Effectiveness of various exercise types in reducing fall risk among older adults with diabetic peripheral neuropathy: A systematic review and meta-analysis

Background

Diabetic peripheral neuropathy (DPN) increases fall risk in diabetics. Due to varying variables used to assess fall risk, the impact of exercise on fall prevention remains inconsistent. This study reviews and compares the effects of different exercises on fall risk among older adults with DPN.

Methods

A comprehensive literature search was conducted in PubMed, EBSCO, Web of Science, and Cochrane Library up to February 17th, 2025. Inclusion criteria were: older adults with DPN; exercise intervention only, an inactive or non-exercising control group, and randomized controlled trials with outcome variables: timed up and go (TUG) time, gait speed, Berg Balance Scale (BBS) score, one-legged standing (OLS) time with eye open (EO) and closed (EC). The mean difference (MD) and 95 % confidence interval (CI) were calculated.

Results

A total of 21 articles included five exercise types: balance exercise (BE), multi-component exercise (ME), strength exercise (SE), whole-body vibration (WBV) and foot-ankle functional training (FT). BE reduced TUG time (MD = -1.47, 95 % CI = -1.79 to -1.15) and increased gait speed (0.11, 0.04-0.18), BBS score (0.93, 0.49-1.37), and OLS time (EO: 2.72, 1.86-3.58; EC:1.58, 1.0-2.17). ME reduced TUG time (-1.71, -2.26 to -1.17) and increased BBS score (2.0, 1.28-2.72) and OLS time (EO: 7.07, 4.35-9.79; EC: 2.61, 1.28-3.94); SE reduced TUG time (-1.45, -2.75 to -0.15) and increased gait speed (0.09, 0.06-0.12); WBV increased OLS time (EO: 1.94, 1.32-2.56; EC: 1.86, 0.16-3.56) but did not affect TUG time or gait speed. FT did not affect TUG time or gait speed.

Conclusions

Exercise reduced fall risks among older adults with DPN. BE and ME were effective in reducing fall risks, followed by SE. WBV improved static balance but failed in dynamic balance. FT showed limited effects on fall prevention and was not recommended.

Five-Year Results With Patisiran for Hereditary Transthyretin Amyloidosis With Polyneuropathy: A Randomized Clinical Trial With Open-Label Extension

Importance

There is a lack of long-term efficacy and safety data on hereditary transthyretin amyloidosis with polyneuropathy (hATTR-PN) and on RNA interference (RNAi) therapeutics in general. This study presents the longest-term data to date on patisiran for hATTR-PN.

Objective

To present the long-term efficacy and safety of patisiran in adults with hATTR-PN.

Design, Setting, and Participants

This global open-label extension (OLE) of the APOLLO randomized clinical trial and phase 2 OLE study enrolled patients from 43 hospitals or clinical centers across 19 countries between July 2015 and August 2017, with follow-up until November 2022. Of 212 eligible patients with hATTR who completed the phase 3 APOLLO or phase 2 OLE parent studies, 211 enrolled in and 138 completed the global OLE.

Intervention

Patisiran, 0.3 mg/kg, intravenously once every 3 weeks for up to 5 years.

Main Outcomes and Measures

Outcomes evaluated at year 5 of the global OLE included disability (polyneuropathy disability [PND] score); polyneuropathy severity (Neuropathy Impairment Score [NIS]), nutritional status (modified body mass index [mBMI]), quality of life (Norfolk Quality of Life-Diabetic Neuropathy [Norfolk QOL-DN]), and Rasch-Built Overall Disability Scale (R-ODS), with no statistical hierarchy. Safety, survival probability, and mortality were also assessed.

Results

At the global OLE baseline, the mean (SD) age was 61.3 (12.3) years, and 156 patients (73.9%) were male. In 138 patients completing the study, PND scores remained stable or improved in 89 patients (65.0%), NISs showed a mean (SD) change of 10.9 (14.7), and mean (SD) mBMI (calculated as weight in kilograms divided by height in meters squared times serum albumin in grams per liter) increased by 46.4 (120.7) over 5 years from baseline. Norfolk QOL-DN and R-ODS scores showed mean (SD) changes of 4.1 (16.7) and -3.7 (6.2), respectively. Adverse events (AEs) leading to study withdrawal occurred in 47 patients (22.3%). Infusion-related reactions were the most common treatment-related AE (n = 34 [16.1%]). Overall, 41 patients (19.4%) died during the study. Patisiran treatment in the parent study and low familial amyloid polyneuropathy score at parent study baseline were associated with significantly improved survival.

Conclusions and Relevance

In the longest study of an RNAi therapeutic for any disease, patisiran treatment resulted in modest changes for patients with hATTR-PN with an acceptable safety profile. These results highlight the importance of initiating early treatment for hATTR and the potential of RNAi therapeutics in medicine.

Trial Registration

ClinicalTrials.gov Identifier: NCT02510261.

Physiological mechanisms of neuromuscular impairment in diabetes-related complications: Can physical exercise help prevent it?

Diabetes mellitus is a chronic disorder that progressively induces complications, compromising daily independence. Among these, diabetic neuropathy is particularly prevalent and contributes to substantial neuromuscular impairments in both types 1 and 2 diabetes. This condition leads to structural damage affecting both the central and peripheral nervous systems, resulting in a significant decline in sensorimotor functions. Alongside neuropathy, diabetic myopathy also contributes to muscle impairment and reduced motor performance, intensifying the neuromuscular decline. Diabetic neuropathy typically implicates neurogenic muscle atrophy, motoneuron loss and clustering of muscle fibres as a result of aberrant denervation-reinervation processes. These complications are associated with compromised neuromuscular junctions, where alterations occur in pre-synaptic vesicles, mitochondrial content and post-synaptic signalling. Neural damage is intensified by chronic hyperglycaemia and oxidative stress, exacerbating vascular dysfunction and reducing oxygen delivery. These complications imply a severe decline in neuromuscular performance, evidenced by reductions in maximal force and power output, rate of force development and muscle endurance. Furthermore, diabetes-related complications are compounded by age-related degenerative changes in long-term patients. Aerobic and resistance training offer promising approaches for managing blood glucose levels and neuromuscular function. Aerobic exercise promotes mitochondrial biogenesis and angiogenesis, supporting metabolic and cardiovascular health. Resistance training primarily enhances neural plasticity, muscle strength and hypertrophy, which are crucial factors for mitigating sarcopenia and preserving functional independence. This topical review examines current evidence on the physiological mechanisms underlying diabetic neuropathy and the potential impact of physical activity in counteracting this decline.

From Morphology to Therapeutic Strategies: Exploring New Applications of Ultrasound for Diabetic Peripheral Neuropathy Diagnosis and Management

Diabetic peripheral neuropathy (DPN) is a common complication of diabetes that can result in severe lower limb pain and amputation. Early detection and treatment of DPN are vital, but this condition is often missed due to a lack of symptoms and the insensitivity of testing methods. This article reviews various ultrasound imaging modalities in the direct and indirect evaluation of peripheral neuropathy. Moreover, how ultrasound-related therapeutic strategies are playing a role in clinical treatment is discussed. Finally, the application of innovative methodologies in the diagnosis of DPN, including ultrasound attenuation, photoacoustic imaging, and artificial intelligence, is described.

One Nervous System: Critical Links Between Central and Peripheral Nervous System Health and Implications for Obesity and Diabetes

There are key differences between the central nervous system (CNS) (brain and spinal cord) and peripheral nervous system (PNS), such as glial cell types, whether there is protection by the blood-brain barrier, modes of synaptic connections, etc. However, there are many more similarities between these two arms of the nervous system, including neuronal structure and function, neuroimmune and neurovascular interactions, and, perhaps most essentially, the balance between neural plasticity (including processes like neuron survival, neurite outgrowth, synapse formation, gliogenesis) and neurodegeneration (neuronal death, peripheral neuropathies like axonopathy and demyelination). This article brings together current research evidence on shared mechanisms of nervous system health and disease between the CNS and PNS, particularly with metabolic diseases like obesity and diabetes. This evidence supports the claim that the two arms of the nervous system are critically linked and that previously understudied conditions of central neurodegeneration or peripheral neurodegeneration may actually be manifesting across the entire nervous system at the same time, through shared genetic and cellular mechanisms. This topic has been critically underexplored due to the research silos between studies of the brain and studies of peripheral nerves and an overemphasis on the brain in neuroscience as a field of study. There are likely shared and linked mechanisms for how neurons stay healthy versus undergo damage and disease among this one nervous system in the body-providing new opportunities for understanding neurological disease etiology and future development of neuroprotective therapeutics.

ARTICLE HIGHLIGHTS

Effectiveness of a web-based foot-ankle exercise program for treating ulcer risk factors in diabetic neuropathy in a randomized controlled trial

The need for strategies to prevent complications from diabetic neuropathy (DPN) is well recognized. However, foot-ankle exercise programs show weak to moderate evidence, and barriers to their implementation persist, including broad and facilitated access to exercise programs, which guarantee for equity. In this paper, we report for the first time the effectiveness of a web-based foot-ankle exercise program aiming to improve DPN-related outcomes, gait biomechanics and functional outcomes. Sixty-two participants with DPN were randomly allocated into the control group (CG; n = 31), which received the usual care, or the intervention group (IG; n = 31), which received the usual care plus a 12-week foot-ankle exercise program using a web-based software (the SOPeD software). The primary outcomes, DPN symptoms and severity, were assessed using the Brazilian version of the Michigan Neuropathy Screening Instrument and the Decision Support System for Classification of Diabetic Polyneuropathy, respectively. Secondary outcomes included tactile sensitivity (monofilaments) and vibration perception (tuning fork), functional outcomes, such as foot pain and function (Foot Health Status Questionnaire), foot muscle strength and plantar pressure during gait (emed plate), and foot-ankle kinematics and kinetics during gait. Outcomes were assessed at baseline, 12 and 24 weeks by an assessor blinded to group allocation. DPN symptoms and severity remained unchanged after the web-based foot-ankle program. However, IG showed improvements compared to CG, with greater functional reach at 12 weeks, better foot function, reduced foot pain and greater plantarflexion degree during push-off at 24 weeks. Regarding plantar loading during gait, the forefoot pressure reduced in the IG at 12 weeks compared to baseline, but at 24 weeks, forefoot load increased in the IG compared to CG. The 12-week web-based foot-ankle exercise program was feasible, acceptable, demonstrating safety with minimal adverse events, such as delayed onset muscle soreness and foot muscle cramping. While DPN-related outcomes were unaffected by the 12-week SOPeD program, modest improvements in foot pain and function, functional reach, and changes in plantar pressure and plantarflexion degree during gait were noted, mostly at 24 weeks.Trial registration: ClinicalTrials.gov, NCT04011267. Registered on 8 July 2019.

An overview of current developments and methods for identifying diabetic foot ulcers: A survey

Diabetic foot ulcers (DFUs) present a substantial health risk across diverse age groups, creating challenges for healthcare professionals in the accurate classification and grading. DFU plays a crucial role in automated health monitoring and diagnosis systems, where the integration of medical imaging, computer vision, statistical analysis, and gait information is essential for comprehensive understanding and effective management. Diagnosing DFU is imperative, as it plays a major role in the processes of diagnosis, treatment planning, and neuropathy research within automated health monitoring and diagnosis systems. To address this, various machine learning and deep learning‐based methodologies have emerged in the literature to support healthcare practitioners in achieving improved diagnostic analyses for DFU. This survey paper investigates various diagnostic methodologies for DFU, spanning traditional statistical approaches to cutting‐edge deep learning techniques. It systematically reviews key stages involved in diabetic foot ulcer classification (DFUC) methods, including preprocessing, feature extraction, and classification, explaining their benefits and drawbacks. The investigation extends to exploring state‐of‐the‐art convolutional neural network models tailored for DFUC, involving extensive experiments with data augmentation and transfer learning methods. The overview also outlines datasets commonly employed for evaluating DFUC methodologies. Recognizing that neuropathy and reduced blood flow in the lower limbs might be caused by atherosclerotic blood vessels, this paper provides recommendations to researchers and practitioners involved in routine medical therapy to prevent substantial complications. Apart from reviewing prior literature, this survey aims to influence the future of DFU diagnostics by outlining prospective research directions, particularly in the domains of personalized and intelligent healthcare. Finally, this overview is to contribute to the continual evolution of DFU diagnosis in order to provide more effective and customized medical care.

This article is categorized under:

Balance evaluation in individuals with type 2 diabetes mellitus with and without peripheral neuropathy

BACKGROUND AND AIMS

Peripheral Diabetic Neuropathy (PDN) is the major complication of diabetes, and sensory-motor impairments can compromise balance, increasing the risk of falls and consequently can lead to functional disability. Thus, this study aims to evaluate the sensory and motor aspects of balance in individuals with type 2 diabetes mellitus with and without PDN.

METHODS

This is a cross-sectional study which analyzed balance in 51 individuals, divided into three groups: G1 - individuals with Peripheral Diabetic Neuropathy; G2 - individuals with diabetics and without PDN; and G3 - individuals without Diabetes Mellitus. As for the instruments used to evaluate balance, specific tests based on model system approach were applied: MiniBESTest and the modified Clinical Test of Sensory Integration of Balance (mCTSIB).

RESULTS

It was observed that individuals in G1 showed balance impairment in mCTSIB and MiniBESTest compared to G2 and G3. In individuals with diabetics without PDN (G2) there was a reduction in tandem position time on the unstable surface and worse anticipatory postural adjustments (APA) and reactive postural response (RPR) compared to individuals without diabetes (G3).

CONCLUSION

PDN showed impairments in both static and dynamic balance, with alterations in sensory orientation, decreased anticipatory and reactive postural response. However, individuals with diabetes and without PDN also present worsening response in tandem position time on the unstable surface, APA and RPR tasks.

Improvement in physical function and lipid profile following low-intensity resistance training and a lower limb conditioning program in people with diabetic neuropathy

BACKGROUND

Diabetic peripheral neuropathy (DPN) impairs glucose and fat metabolism and physical functioning. This study examined the effects of low-intensity resistance exercise training (LI-RT) and a lower limb conditioning program (LLCP) on physical function and lipid profile in DPN.

METHODS

Forty-five diabetic women with mild to moderate neuropathy (55.5 ± 3.1 y) were randomly assigned to one of three groups: LI-RT (n = 15), LLCP (n = 15), and control (n = 15). The LI-RT and LLCP groups trained 3 times/week (90 min/session) for 12 weeks. The LI-RT group completed 3 sets of 10 repetitions for ten exercises at 30-repetition maximum; the LLCP group performed 12 lower extremity motions designed for peripheral neuropathy; and the control group followed their routine daily activities. Physical function was assessed using the Timed Up and Go Test (TUG), Five Times Sit-to-Stand (FTSTS) test, and 6-min walking test (6MWT). Blood lipid profile was assessed.

RESULTS

Both the LI-RT and LLCP groups significantly improved in TUG scores compared to the control group (p ≤ 0.05). No significant changes between groups were observed for the FTSTS and 6MWT. The LI-RT and LLCP groups, compared to the control group, showed a significant reduction in low-density lipoprotein (p ≤ 0.05), and triglycerides (p ≤ 0.001). High-density lipoproteins showed non-significant changes.

CONCLUSION

Low intensity training involving resistance exercises or lower limb range of motion enhance physical function and lipid profile in patients with DPN. High intensity exercise could be risky and deter adherence. Hence, these gentler exercise programs offer viable options for enhancing health and fitness in DPN patients.

SGLT2 inhibitors: a novel therapy for cognitive impairment via multifaceted effects on the nervous system

The rising prevalence of diabetes mellitus has casted a spotlight on one of its significant sequelae: cognitive impairment. Sodium-glucose cotransporter-2 (SGLT2) inhibitors, originally developed for diabetes management, are increasingly studied for their cognitive benefits. These benefits may include reduction of oxidative stress and neuroinflammation, decrease of amyloid burdens, enhancement of neuronal plasticity, and improved cerebral glucose utilization. The multifaceted effects and the relatively favorable side-effect profile of SGLT2 inhibitors render them a promising therapeutic candidate for cognitive disorders. Nonetheless, the application of SGLT2 inhibitors for cognitive impairment is not without its limitations, necessitating more comprehensive research to fully determine their therapeutic potential for cognitive treatment. In this review, we discuss the role of SGLT2 in neural function, elucidate the diabetes-cognition nexus, and synthesize current knowledge on the cognitive effects of SGLT2 inhibitors based on animal studies and clinical evidence. Research gaps are proposed to spur further investigation.

Muscle Network Connectivity Study in Diabetic Peripheral Neuropathy Patients

Diabetic peripheral neuropathy (DPN) is a prevalent complication of chronic diabetes mellitus and has a significant impact on quality of life. DPN typically manifests itself as a symmetrical, length-dependent sensorimotor polyneuropathy with severe effects on gait. Surface electromyography (sEMG) is a valuable low-cost tool for assessing muscle activation patterns and precise identification of abnormalities. For the present study, we used information theory methods, such as cross-correlation (CC), normalized mutual information (NMI), conditional granger causality (CG-Causality), and transfer entropy (TE), to evaluate muscle network connectivity in three population groups: 33 controls (healthy volunteers, CT), 10 diabetic patients with a low risk of DPN (LW), and 17 moderate/high risk patients (MH). The results obtained indicated significant alterations in the intermuscular coupling mechanisms due to diabetes and DPN, with the TE group showing the best performance in detecting differences. The data revealed a significant increase in information transfer and muscle connectivity in the LW group over the CT group, while the MH group obtained significantly lower values for these metrics than the other two groups. These findings highlight the sEMG coupling metrics' potential to reveal neuromuscular mechanisms that could aid the development of targeted rehabilitation strategies and help monitor DPN patients.

Weakness Status is Differentially Associated with Time to Diabetes in Americans

Background

The purpose of this study was to evaluate the associations of (1) individual absolute and body size normalized weakness cut-points, and (2) the collective weakness classifications on time to diabetes in Americans.

Methods

We analyzed data from 9577 adults aged at least 50-years from the Health and Retirement Study. Diabetes diagnosis was self-reported. A handgrip dynamometer measured handgrip strength (HGS). Males with HGS <35.5 kg (absolute), <0.45 kg/kg (normalized to body weight), or <1.05 kg/kg/m2 (normalized to BMI) were categorized as weak. Females were classified as weak if their HGS was <20.0 kg, <0.337 kg/kg, or <0.79 kg/kg/m2. Compounding weakness included falling below 1, 2, or all 3 cut-points.

Results

Persons below the body weight normalized weakness cut-points had a 1.29 (95% confidence interval (CI): 1.15-1.47) higher hazard for incident diabetes, while those below the BMI normalized cut-points had a 1.30 (CI: 1.13-1.51) higher hazard. The association between absolute weakness and incident diabetes was insignificant (hazard ratio: 1.06; CI: 0.91-1.24). Americans below 1, 2, or all 3 collective weakness categories had a 1.28 (CI: 1.10-1.50), 1.29 (CI: 1.08-1.52), and 1.33 (CI: 1.09-1.63) higher hazard for the incidence of diabetes, respectively.

Conclusions

Our findings indicate that while absolute weakness, which is confounded by body size, was not associated with time to diabetes, adjusting for the influence of body size by normalizing HGS to body weight and BMI was significantly associated with time to diabetes. This suggests that muscle strength, not body size, may be driving such associations with time to diabetes.

Combined effects of strength and balance training versus aerobic training on balance, neuropathy symptoms and quality of life in patients with diabetic peripheral neuropathy

BACKGROUND

Diabetic peripheral neuropathy (DPN) occurs in >50% of diabetic patients and is a high risk-factor of balance problems and risk of falls. Impaired balance can lead to reduced function, which has a detrimental effect on patients' quality of life. Structured strength and balance training can result in sustained improvements in muscle strength, coordination, balance, functional status and quality of life.

OBJECTIVE

To determine the combined effects of strength and balance training versus aerobic training on balance, severity of symptoms of DPN, and quality of life in patients with DPN.

METHODS

This double blinded, two arm parallel design Randomized Clinical Trial. The study was conducted from March to December 2020 in the AIMS diabetic center Peshawar, Pakistan. Participants were selected through convenience sampling technique and randomly allocated into strength plus balance and aerobic training groups. Type 2 diabetic patients of both sexes, aged 40 to 80 years, with a Toronto neuropathy score ≥6 recruited, while patients with ulceration/infection of feet, medical/Surgical conditions, and non-ambulatory patients were excluded from this study. Intervention was applied 3 days a week for 8 weeks. The Toronto clinical neuropathy system was used to assess neuropathy severity, SF-36 to assess quality of life and the Berg balance scale was used for assessment of balance. Assessment was done at the baseline and after 8 weeks of intervention using SPSS. Version 22 was used for analysis.

RESULTS

The mean age of the participants was 60.80 ± 9.73. Between group analysis, which showed were statistically insignificant for neuropathy severity, balance and all domains of quality of life (p-value >0.05) except SF-36 General Health Perception Score, with Mean ± SD of 62.50 ± 7.54 in group A versus Mean ± SD of in group B 60.00 ± 15.98 (p-value = 0.05). Within group analysis showed statistically significant results for neuropathy severity, balance and all domains of quality of life (p-value<0.05).

CONCLUSION

This study concluded that there is a statistically significant effect of structured balance and strength training and aerobic training on severity of DPN, balance and quality of life. But there was no statistically significant difference in improvement between the two intervention groups.

Shoulder muscle weakness and proprioceptive impairments in type 2 diabetes mellitus: exploring correlations for improved clinical management

Background

Type 2 diabetes mellitus (T2DM) is a prevalent metabolic disorder with systemic implications, potentially affecting musculoskeletal health. This study aimed to assess shoulder muscle strength and joint repositioning accuracy in individuals with T2DM, exploring potential correlations and shedding light on the musculoskeletal consequences of the condition. The objectives were two-fold: (1) to assess and compare shoulder strength and joint repositioning accuracy between individuals with T2DM and asymptomatic counterparts, and (2) to examine the correlation between shoulder strength and joint repositioning accuracy in individuals with T2DM.

Methods

A cross-sectional study enrolled 172 participants using the convenience sampling method, including 86 individuals with T2DM and an age-matched asymptomatic group (n = 86). Shoulder strength was assessed using a handheld dynamometer, while joint repositioning accuracy was evaluated with an electronic digital inclinometer.

Results

Individuals with T2DM exhibited reduced shoulder muscle strength compared to asymptomatic individuals (p < 0.001). Additionally, joint repositioning accuracy was significantly lower in the T2DM group (p < 0.001). Negative correlations were observed between shoulder strength and joint repositioning accuracy in various directions (ranging from -0.29 to -0.46, p < 0.001), indicating that higher muscle strength was associated with improved joint repositioning accuracy in individuals with T2DM.

Conclusion

This study highlights the significant impact of T2DM on shoulder muscle strength and joint repositioning accuracy. Reduced strength and impaired accuracy are evident in individuals with T2DM, emphasizing the importance of addressing musculoskeletal aspects in diabetes management. The negative correlations suggest that enhancing shoulder muscle strength may lead to improved joint repositioning accuracy, potentially contributing to enhanced physical functioning in this population.

CGRP sensory neurons promote tissue healing via neutrophils and macrophages

The immune system has a critical role in orchestrating tissue healing. As a result, regenerative strategies that control immune components have proved effective1,2. This is particularly relevant when immune dysregulation that results from conditions such as diabetes or advanced age impairs tissue healing following injury2,3. Nociceptive sensory neurons have a crucial role as immunoregulators and exert both protective and harmful effects depending on the context4-12. However, how neuro-immune interactions affect tissue repair and regeneration following acute injury is unclear. Here we show that ablation of the NaV1.8 nociceptor impairs skin wound repair and muscle regeneration after acute tissue injury. Nociceptor endings grow into injured skin and muscle tissues and signal to immune cells through the neuropeptide calcitonin gene-related peptide (CGRP) during the healing process. CGRP acts via receptor activity-modifying protein 1 (RAMP1) on neutrophils, monocytes and macrophages to inhibit recruitment, accelerate death, enhance efferocytosis and polarize macrophages towards a pro-repair phenotype. The effects of CGRP on neutrophils and macrophages are mediated via thrombospondin-1 release and its subsequent autocrine and/or paracrine effects. In mice without nociceptors and diabetic mice with peripheral neuropathies, delivery of an engineered version of CGRP accelerated wound healing and promoted muscle regeneration. Harnessing neuro-immune interactions has potential to treat non-healing tissues in which dysregulated neuro-immune interactions impair tissue healing.

Exercise May Increase Oxidative Stress in the Sciatic Nerve in Streptozotocin-Induced Diabetic Rats

Background and Objectives: Diabetic peripheral neuropathy (DPN) affects approximately half of patients with diabetes mellitus (DM), contributing to falls and fractures. Oxidative stress, which is linked to DM-induced hyperglycemia, has been implicated in the onset of DPN. Although exercise is recommended for patients with DM, its effect on DPN remains unclear. Therefore, this study aimed to investigate the effect of exercise on DPN and the mechanisms involved. Material and Methods: Thirty male Wistar rats were divided into control, streptozotocin (STZ)-induced diabetic (DM), and STZ-induced diabetic/exercise (DM + Ex) groups. Diabetes was induced using STZ injection. Rats in the DM + Ex groups underwent six weeks of treadmill exercise. Sciatic nerve parameters, which included motor nerve conduction velocity (MNCV), antioxidant enzymes (catalase, glutathione peroxidase [GPx], and superoxide dismutase [SOD]), oxidative stress markers (malondialdehyde [MDA] and 4-hydroxy-2-nonenal [4HNE]), and neurotrophic factors (brain-derived neurotrophic factor [BDNF] and nerve growth factor [NGF]), were examined. Results: Exercise alleviated DM-induced decreases in MNCV in rats. Although exercise did not significantly affect antioxidant enzyme activity, 4HNE levels increased significantly, indicating increased oxidative stress. Additionally, exercise did not significantly affect DM-induced increases in NGF and BDNF levels in rats. Conclusions: Exercise may prevent DPN in rats with DM, possibly through nonantioxidant mechanisms.

Effects of low-intensity exercise on contractile property of skeletal muscle and the number of motor neurons in diabetic rats

The mode of diabetes-induced muscle and motor neuron damage depends on the type of muscle and motor neuron. One of the purposes of exercise therapy for diabetes is to improve blood glucose levels; however, information on the effects of low-intensity exercise on muscle and motor neuron disorders remain unknown. Therefore, this study aimed to examine the effects of low-intensity exercise on diabetes-induced muscle and motor neuron damage in a rat model of type 1 diabetes mellitus. We subjected adult male Wistar rats treated with streptozotocin to develop type 1 diabetes and age-matched rats to low-intensity treadmill exercise for 12 weeks. We recorded electrically evoked maximum twitch tension in leg muscles, and examined the number of motor neurons and cell body sizes. Low-intensity exercise ameliorated the prolonged half-relaxation time and the decreased numbers of the retrograde-labeled motor neurons observed in the soleus muscle of type 1 diabetic rats. However, no effect was observed in the diabetic group, as atrophy was not improved and the twitch force in the medial gastrocnemius muscle was decreased in the diabetic group. In addition, there was no improvement in the blood glucose levels after exercise. These data indicate that low-intensity exercise may relieve the onset of muscle and motor neuron damage in the soleus muscle of type 1 diabetic rats.

Behavior of neuropathy symptom score and neuropathy disability score in patients with and without peripheral diabetic neuropathy: A retrospective cohort study

BACKGROUND

This study aimed to stablish cut-off of early diagnosis of diabetic polyneuropathy (PDN) based on neuropathy symptom score (NSS) and neuropathy disability score (NDS); to determine the behavior of NDD and NDS in patients with and without PDN; and to verify the association between clinical and demographic variables with both tests.

METHODS

This retrospective cohort included 86 patients with diabetes. The NSS and NDS evaluations were collected in medical records in two moments: initial (entry into service) and final (after three years). Individuals were categorized in three groups: G1- PDN in both evaluations (N = 27); G2- PDN only in the final evaluation (N = 16); G3-individuals without PDN (N = 43). A ROC curve was performed to evaluate the sensitivity and specificity of NSS and NDS for PDN diagnosis. ANOVA was used to compare NSS and NDS between groups and evaluations, and multiple regression was performed to find predictors of PDN.

RESULTS

The NSS and NDS showed excellent sensitivity and specificity (NDS ≥1.5 and NSS ≥6.5) for PDN diagnosis. There was a significant difference between groups in initial (p = 0.000) and final (p = 0.000) NDS and NSS evaluations. There was an association between peripheral arterial disease (PAD) and increase in NSS (p = 0.024) in G2; and association between loss of protective sensation (LOPS) and increase in NSS in G3 (p < 0.001).

CONCLUSION

NSS and NDS tests showed excellent sensitivity and specificity for early PDN diagnosis. Behavior of both tests can differ patients with and without PDN. Furthermore, PAD and LOPS can be a predictor of PDN evolution.

Understanding the role of hyperglycemia and the molecular mechanism associated with diabetic neuropathy and possible therapeutic strategies

Diabetic neuropathy is a neuro-degenerative disorder that encompasses numerous factors that impact peripheral nerves in the context of diabetes mellitus (DM). Diabetic peripheral neuropathy (DPN) is very prevalent and impacts 50% of diabetic patients. DPN is a length-dependent peripheral nerve lesion that primarily causes distal sensory loss, discomfort, and foot ulceration that may lead to amputation. The pathophysiology is yet to be fully understood, but current literature on the pathophysiology of DPN revolves around understanding various signaling cascades involving the polyol, hexosamine, protein-kinase C, AGE, oxidative stress, and poly (ADP ribose) polymerase pathways. The results of research have suggested that hyperglycemia target Schwann cells and in severe cases, demyelination resulting in central and peripheral sensitization is evident in diabetic patients. Various diagnostic approaches are available, but detection at an early stage remains a challenge. Traditional analgesics and opioids that can be used "as required" have not been the mainstay of treatment thus far. Instead, anticonvulsants and antidepressants that must be taken routinely over time have been the most common treatments. For now, prolonging life and preserving the quality of life are the ultimate goals of diabetes treatment. Furthermore, the rising prevalence of DPN has substantial consequences for occupational therapy because such therapy is necessary for supporting wellness, warding off other chronic-diseases, and avoiding the development of a disability; this is accomplished by engaging in fulfilling activities like yoga, meditation, and physical exercise. Therefore, occupational therapy, along with palliative therapy, may prove to be crucial in halting the onset of neuropathic-symptoms and in lessening those symptoms once they have occurred.

Effects of Photobiomodulation With Two Wavelengths of 630 and 810 nm on Diabetic Neuropathy

Introduction: Diabetic peripheral neuropathy (DPN) is the most common complication of diabetes patients. Among different therapeutic approaches for treating DPN, low-level laser therapy (LLLT) or photobiomodulation (PBM) is a new promising non-invasive technique. This study aims to evaluate the effect of visible and infra-red LLLT on DPN. Methods: Sixty DPN patients enrolled in a randomized-controlled study. The patients were randomly divided into the same population of control and laser groups. The patients in the laser group received LLLT with two wavelengths of 630 and 819 nm and conventional therapy, and those in the control group received conventional therapy alone. Irradiation of the patients lasted 15 minutes per session, and it was performed over the surface of each foot three times a week for 12 sessions. The patients were evaluated at baseline and at the end of the study with the Michigan Neuropathy Screening Instrument (MNSI) and microfilament test. Results: Patients' sensation in the right foot in the monofilament test had increased from 22 (84.6%) to 26 (86.7%) (P=0.000), and in the left foot it had increased from 20 (80%) to 25 (86.2%) (P=0.001). The mean and standard deviation of the scores of section A of the Michigan questionnaire showed a statistically significant difference between the two groups (P<0.05), but the B part scores of the Michigan test did not show a significant difference. Conclusion: This study showed that the visible and infra-red LLLT significantly improved the symptoms of diabetic neuropathy without any side effects.

Incidence of accidental falls and development of a fall risk prediction model among elderly patients with diabetes mellitus: A prospective cohort study

AIMS

To investigate the incidence of accidental falls and develop a fall risk prediction tool in elderly patients with diabetes mellitus.

BACKGROUND

The risk of fall in elderly patients with diabetes is higher than that in the general elderly, there is fewer fall assessment tools for elderly patients with diabetes.

DESIGN

A prospective cohort study.

METHODS

Between June and September 2019, a total of 1007 elderly patients with diabetes were enrolled from a tertiary specialist diabetes hospital in Tianjin and were prospectively followed up for 6 months to determine outcomes of accidental falls through telephone. Demographic and diseases related factors were collected at baseline. Incidence of falls was investigated, and a nomogram was developed based on logistic regression model. SPSS 21.0 and R 3.6.3 were used to analyse the data. The article was reported in accordance with STROBE guidelines.

RESULTS

Among 1007 elderly patients, 950 finished the follow-up. A total of 133 falls occurred in 93 patients during the follow-up period, with a fall rate of 9.79%. Diabetic peripheral neuropathy, walking aids, depression, fall history, fatigue and sex were independent predictors of accidental fall in diabetes elderly patients. The sensitivity and specificity of the predictive model were 73.12% and 52.63%, respectively, and a fall risk prediction nomogram was developed based on the regression model.

CONCLUSIONS

A nomogram including 6 easily available prediction factors (diabetic peripheral neuropathy, walking aids, depression, fall history within 1 year, fatigue, sex) was developed, and it can be used in safety management among Chinese elderly patients diagnosed with diabetes.

RELEVANCE TO CLINICAL PRACTICE

Nomogram can be used to identify diabetic elderly patients at high risk of accidental falls.

Associations of metabolic heterogeneity of obesity with frailty progression: Results from two prospective cohorts

BACKGROUND

Previous studies indicated that obesity would accelerate frailty progression. However, obesity is heterogeneous by different metabolic status. The associations of metabolic heterogeneity of obesity with frailty progression remain unclear.

METHODS

A total of 6730 participants from the China Health and Retirement Longitudinal Study (CHARLS) and 4713 from the English Longitudinal Study of Ageing (ELSA) were included at baseline. Metabolic heterogeneity of obesity was evaluated based on four obesity and metabolic phenotypes as metabolically healthy normal weight (MHNW), metabolically unhealthy normal weight (MUNW), metabolically healthy overweight/obesity (MHOO), and metabolically unhealthy overweight/obesity (MUOO). Frailty status was assessed by the frailty index (FI) ranging from 0 to 100 and frailty was defined as FI ≥ 25. Linear mixed-effect models were used to analyse the associations of metabolic heterogeneity of obesity with frailty progression.

RESULTS

In the CHARLS, MUOO and MUNW presented the accelerated FI progression with additional annual increases of 0.284 (95% CI: 0.155 to 0.413, P < 0.001) and 0.169 (95% CI: 0.035 to 0.303, P = 0.013) as compared with MHNW. MHOO presented no accelerated FI progression (β: -0.011, 95% CI: -0.196 to 0.173, P = 0.904) as compared with MHNW. In the ELSA, the accelerated FI progression was marginally significant for MUOO (β: 0.103, 95% CI: -0.005 to 0.210, P = 0.061) and MUNW (β: 0.157, 95% CI: -0.011 to 0.324, P = 0.066), but not for MHOO (β: -0.047, 95% CI: -0.157 to 0.062, P = 0.396) in comparison with MHNW. The associations of MUOO and MUNW with the accelerated FI progression were stronger after excluding the baseline frail participants in both cohorts. The metabolic status changed over time. When compared with stable MHNW, participants who changed from MHNW to MUNW presented the accelerated FI progression with additional annual increases of 0.356 (95% CI: 0.113 to 0.599, P = 0.004) and 0.255 (95% CI: 0.033 to 0.477, P = 0.024) in the CHARLS and ELSA, respectively. The accelerated FI progression was also found in MHOO participants who transitioned to MUOO (CHARLS, β: 0.358, 95% CI: 0.053 to 0.663, P = 0.022; ELSA, β: 0.210, 95% CI: 0.049 to 0.370, P = 0.011).

CONCLUSIONS

Metabolically unhealthy overweight/obesity and normal weight, but not metabolically healthy overweight/obesity, accelerated frailty progression as compared with metabolically healthy normal weight. Regardless of obesity status, transitions from healthy metabolic status to unhealthy metabolic status accelerated frailty progression as compared with stable metabolically healthy normal weight. Our findings highlight the important role of metabolic status in frailty progression and recommend the stratified management of obesity based on metabolic status.

Morphological and Mechanical Properties of Lower-Limb Muscles in Type 2 Diabetes: New Potential Imaging Indicators for Monitoring the Progress of DPN

The aim of this study was to explore changes in morphological and mechanical properties of lower-limb skeletal muscles in patients with diabetes with and without diabetic peripheral neuropathy (DPN) and seek to find a potential image indicator for monitoring the progress of DPN in patients with type 2 diabetes mellitus (T2DM). A total of 203 patients with T2DM, with and without DPN, were included in this study. Ultrasonography and ultrasound shear wave imaging (USWI) of the abductor hallux (AbH), tibialis anterior (TA), and peroneal longus (PER) muscles were performed for each subject, and the shear wave velocity (SWV) and cross-sectional area (CSA) of each AbH, TA, and PER were measured. The clinical factors influencing AbH_CSA and AbH_SWV were analyzed, and the risk factors for DPN complications were investigated. AbH_CSA and AbH_SWV in the T2DM group with DPN decreased significantly (P < 0.05), but no significant differences were found in the SWV and CSA of the TA and PER between the two groups. Toronto Clinical Scoring System (CSS) score and glycosylated hemoglobin (HbA1c) were independent predictors of AbH_CSA and AbH_SWV. As AbH_SWV and AbH_CSA decreased, Toronto CSS score and HbA1c increased and incidence of DPN increased significantly. In conclusion, the AbH muscle of T2DM patients with DPN became smaller and softer, while its morphological and mechanical properties were associated with the clinical indicators related to the progression of DPN. Thus, they could be potential imaging indicators for monitoring the progress of DPN in T2DM patients.

Diabetes and physical activity: A prospective cohort study

Diabetes is on the rise as the worldwide population ages. While physical activity can help protect against diabetes, ageing is commonly associated with reduced physical activity. This study aimed to examine if physical activity differs by diabetes status in mid-aged adults, how this association changes over time, and whether physical activity-related sociodemographic factors and health indicators differ in those with and without diabetes. Data came from four waves of the How Areas in Brisbane Influence HealTh and AcTivity (HABITAT), a longitudinal study of mid-age adults living in Brisbane, Australia. Random effects/Expectation-maximisation (RE-EM) regression trees were used to identify factors affecting physical activity among those with and without diabetes, both separately and combined. At study entry, those with diabetes had a higher median age of 58 years (95% CI: 57-60) and a lower median physical activity of 699 MET.min/week (95% CI: 599-799) than people without diabetes (53 years (95% CI: 53-53) and 849 MET.min/week (95% CI: 799-899)). However, the strongest factors influencing physical activity were BMI and gender, not diabetes status. It is vital to promote physical activity among adults, in particular among those with high BMI and women, as well as those with and at high risk of diseases like diabetes.

Increased serum levels of advanced glycation end products are negatively associated with relative muscle strength in patients with type 2 diabetes mellitus

BACKGROUND

In this study, we investigated whether serum levels of advanced glycation end products (AGEs) independently correlated with relative muscle strength after adjustment for clinical variables including diabetic peripheral neuropathy in patients with type 2 diabetes. Relative muscle strength was defined as muscle strength (in decinewtons, dN) divided by total muscle mass (in kg).

METHODS

We enrolled 152 ambulatory patients with type 2 diabetes. Each participant underwent measurements of muscle strength and total muscle mass. Serum levels of AGEs were determined. The Michigan Neuropathy Screening Instrument Physical Examination (MNSI-PE) was performed to assess diabetic peripheral neuropathy.

RESULTS

The participants were divided into three groups on the basis of tertiles of serum AGEs levels. Significant differences were observed among the three groups in relative handgrip strength (71.03 ± 18.22, 63.17 ± 13.82, and 61.47 ± 13.95 dN/kg in the low-tertile, mid-tertile, and high-tertile groups, respectively, P = 0.005). The relative muscle strength of the ankle plantar flexors was higher in the low-tertile group than in the mid-tertile and high-tertile groups (107.60 ± 26.53, 94.97 ± 19.72, and 94.18 ± 16.09 dN/kg in the low-tertile, mid-tertile, and high-tertile groups, respectively, P = 0.002). After adjustment for MNSI-PE score and other clinical variables in partial correlation analysis, the correlations between serum levels of AGEs and the relative muscle strength of handgrip, ankle dorsiflexor, and ankle plantar flexor remained significant. Serum AGEs level was the only variable that remained significantly related to the relative muscle strength of handgrip, ankle dorsiflexor, and ankle plantar flexor when AGEs level, fasting plasma glucose, and glycated hemoglobin (HbA1c) were entered into multiple regression models simultaneously.

CONCLUSIONS

After adjustment for multiple factors including diabetic peripheral neuropathy, this study demonstrated that increased serum levels of AGEs were independently associated with decreased relative muscle strength in patients with type 2 diabetes. Compared with fasting plasma glucose and HbA1c, serum level of AGEs is more strongly associated with relative muscle strength.

10.6-μm infrared laser as adjuvant therapy for diabetic peripheral neuropathy: study protocol for a double-blind, randomized controlled trial

Background

Diabetic peripheral neuropathy (DPN) is the most common chronic neurological complication. It is the main cause of disability in diabetes mellitus (DM) patients and seriously affects the quality of life of patients. Pharmacological treatments always associate with limited efficacy and adverse effects. Moxibustion has been recommended to treat DPN as an adjuvant therapy to conventional medical treatment to accelerate alleviation of the symptoms of DPN. 10.6-μm laser moxibustion (LM), whose wavelength is close to the peak of infrared radiation spectrum of the traditional moxibustion as well as human acupoints, produces the thermal effect similar with moxibustion but with no smoke or smell. The purpose of this sham controlled clinical trial is to determine the effect and safety of 10.6-μm LM as adjuvant therapy in patients with DPN.

Methods

This is a protocol for a randomized, double-blind, sham-controlled trial. One hundred fourteen patients meeting the inclusion and exclusion criteria will be recruited and randomly assigned to the LM group or the sham LM group with a 1:1 allocation ratio. Patients in both groups will receive a basic integrated treatment of Chinese and Western medicine and a total of 12 sessions of true or sham LM treatments over 4 weeks with 3 sessions a week. The primary outcome is nerve conduction velocity (NCV), and the secondary outcomes include Michigan Neuropathy Screening Instrument (MNSI) scores, Diabetes-Specific Quality of Life (DSQL) scores, blood rheology parameters, and assessments of safety and blinding. Outcome measures will be collected at baseline, 2 weeks after treatment, the end of LM treatments (4 weeks), and 4, 8 weeks after the end of LM treatment (8, 12weeks).

Discussion

This study will be conducted to compare the efficacy of LM versus sham LM combined with medical treatment. 10.6-μm LM may alleviate symptoms, improve quality of life, and reduce the dosage of drugs as well as avoid causing serious side effects.

Trial registration

Chinese Clinical Trial Registry ChiCTR2000029329. Registered on 25 January 2020.

Exercise as Treatment for Neuropathy in the Setting of Diabetes and Prediabetic Metabolic Syndrome: A Review of Animal Models and Human Trials

BACKGROUND

Peripheral neuropathy is among the most common complications of diabetes, but a phenotypically identical distal sensory predominant, painful axonopathy afflicts patients with prediabetic metabolic syndrome, exemplifying a spectrum of risk and continuity of pathogenesis. No pharmacological treatment convincingly improves neuropathy in the setting of metabolic syndrome, but evolving data suggest that exercise may be a promising alternative.

OBJECTIVE

The aim of the study was to review in depth the current literature regarding exercise treatment of metabolic syndrome neuropathy in humans and animal models, highlight the diverse mechanisms by which exercise exerts beneficial effects, and examine adherence limitations, safety aspects, modes and dose of exercise.

RESULTS

Rodent models that recapitulate the organismal milieu of prediabetic metabolic syndrome and the phenotype of its neuropathy provide a strong platform to dissect exercise effects on neuropathy pathogenesis. In these models, exercise reverses hyperglycemia and consequent oxidative and nitrosative stress, improves microvascular vasoreactivity, enhances axonal transport, ameliorates the lipotoxicity and inflammatory effects of hyperlipidemia and obesity, supports neuronal survival and regeneration following injury, and enhances mitochondrial bioenergetics at the distal axon. Prospective human studies are limited in scale but suggest exercise to improve cutaneous nerve regenerative capacity, neuropathic pain, and task-specific functional performance measures of gait and balance. Like other heath behavioral interventions, the benefits of exercise are limited by patient adherence.

CONCLUSION

Exercise is an integrative therapy that potently reduces cellular inflammatory state and improves distal axonal oxidative metabolism to ameliorate features of neuropathy in metabolic syndrome. The intensity of exercise need not improve cardinal features of metabolic syndrome, including weight, glucose control, to exert beneficial effects.

The role of adipose-derived stem cells-derived extracellular vesicles in the treatment of diabetic foot ulcer: Trends and prospects

Diabetic foot ulcer(DFU) is one of the most severe chronic complications of type 2 diabetes mellitus, which is mainly caused by peripheral vascular occlusion with various degrees of infection. Treatment of DFU is difficult, and ulcer formation in lower limbs and deep-tissue necrosis might lead to disability or even death. Insulin resistance is the major mechanism of type 2 diabetes mellitus development, largely caused by adipose tissue dysfunction. However, adipose tissue was recently identified as an important endocrine organ that secretes bio-active factors, such as adipokines and extracellular vesicles(EVs). And adipose tissue-derived stem cells(ADSCs) are abundant in adipose tissue and have become a hot topic in the tissue engineering field. In particular, EVs derived from ADSCs contain abundant biomarkers and mediators. These EVs exert significant effects on distant cells and organs, contributing to metabolic homeostasis. In this review, we aim to elaborate on the mechanisms of diabetic non-healing wound development and the role of ADSCs-EVs in wound repair, which might provide a new therapy for treating DFU.

Sirtuin 3 overexpression preserves maximal sarco(endo)plasmic reticulum calcium ATPase activity in the skeletal muscle of mice subjected to high fat-high sucrose-feeding

Sarco(endo)plasmic reticulum calcium (Ca²⁺) ATPase (SERCA) transports Ca²⁺ in muscle. Impaired SERCA activity contributes to diabetic myopathy. Sirtuin (SIRT) 3 regulates muscle metabolism and function. However, it is unknown if SIRT3 regulates muscle SERCA activity. We determined if SIRT3 overexpression enhances SERCA activity in mouse gastrocnemius muscle and if SIRT3 overexpression preserves gastrocnemius SERCA activity in a model of type 2 diabetes, induced by high fat-high sucrose (HFHS)-feeding. We also determined if the acetylation status of SERCA proteins in mouse gastrocnemius is altered by SIRT3 overexpression or HFHS-feeding. Wild-type (WT) mice and SIRT3 transgenic (SIRT3_TG) mice, overexpressing SIRT3 in skeletal muscle, were fed a standard- or HFHS-diet for 4-months. SIRT3_TG and WT mice developed obesity and glucose intolerance after 4-months of HFHS-feeding. SERCA V_max was higher in gastrocnemius of SIRT3TG mice, compared to WT mice. HFHS-fed mice had lower SERCA1a protein levels and lower SERCA V_max in their gastrocnemius than control-fed mice. The decrease in SERCA V_max in gastrocnemius muscle due to HFHS-feeding was attenuated by SIRT3 overexpression in HFHS-fed SIRT3_TG mice. SERCA1a and SERCA2a acetylation in mouse gastrocnemius was not altered by genotype or diet. These findings suggest SIRT3 overexpression improves SERCA function in diabetic mouse skeletal muscle.

The Associations between Asymmetric Handgrip Strength and Chronic Disease Status in American Adults: Results from the National Health and Nutrition Examination Survey

This study examined the associations between asymmetric handgrip strength (HGS) and multimorbidity in American adults. Secondary analyses of data from persons aged at least 40 years from the 2011-2012 and 2013-2014 waves of the National Health and Nutrition Examination Survey were conducted. A handheld dynamometer collected HGS on each hand and persons with a strength imbalance >10% between hands were classified as having asymmetric HGS. Adults with the presence of ≥2 of the following conditions had multimorbidity: cardiovascular disease, chronic obstructive pulmonary disease, chronic kidney disease, asthma, arthritis, cancer, obesity, stroke, hypertension, high cholesterol, and diabetes. Of the n = 3483 participants included, n = 2700 (77.5%) had multimorbidity. A greater proportion of adults with multimorbidity had HGS asymmetry (n = 1234 (45.7%)), compared to persons living without multimorbidity (n = 314 (40.1%); p < 0.05). Relative to individuals without asymmetry, adults with asymmetric HGS had 1.31 (95% confidence interval (CI): 1.03-1.67) greater odds for multimorbidity. Moreover, persons with HGS asymmetry had 1.22 (CI: 1.04-1.44) greater odds for accumulating morbidities. Asymmetric strength, as another indicator of diminished muscle function, is linked to chronic morbidity status. Healthcare providers should recommend healthy behaviors for reducing asymmetries to improve muscle function and mitigate morbidity risk after completing asymmetry screenings.

Immediate Effect of Manual Therapy on Tibiotarsal Joint Mobility and Static Balance in Individuals With Diabetes

Objectives

The objective of this study was to evaluate the immediate effect of manual therapy on ankle joint mobility and static balance in patients with diabetes.

Methods

Forty patients, at a mean age of 59.35 ± 7.85, with type 2 diabetes mellitus and neurologic symptoms according to a Neuropathy Symptom Score protocol with amplitude, were included. The patients were divided into 2 groups: sham group and intervention group, which underwent manual manipulation intervention and 7-day follow-up. Joint range-of-motion analysis was performed using digital goniometry and static discharge of weights assessed by computerized baropodometry with open and closed eyes. The Shapiro-Wilk normality test was used to analyze the distribution. The data showed normal distribution, so the analysis of variance tests followed by Tukey's tests were used. SAS statistical software was used and the significance level was 5%.

Results

The results of the intervention group showed an increase in the variable ankle goniometry over time compared to the sham group. The dorsiflexion movement on the right side obtained major gains over time; in addition, plantar flexion increased.

Conclusion

Based on the participants evaluated in this study, manual therapy increased the ankle joint amplitude and improved the static balance in individuals with diabetes.

The Impact of Glucose-Lowering Drugs on Sarcopenia in Type 2 Diabetes: Current Evidence and Underlying Mechanisms

The age-related decrease in skeletal muscle mass together with the loss of muscle power and function is defined sarcopenia. Mounting evidence suggests that the prevalence of sarcopenia is higher in patients with type 2 diabetes mellitus (T2DM), and different mechanisms may be responsible for this association such as impaired insulin sensitivity, chronic hyperglycemia, advanced glycosylation end products, subclinical inflammation, microvascular and macrovascular complications. Glucose-lowering drugs prescribed for patients with T2DM might impact on these mechanisms leading to harmful or beneficial effect on skeletal muscle. Importantly, beyond their glucose-lowering effects, glucose-lowering drugs may affect per se the equilibrium between protein anabolism and catabolism through several mechanisms involved in skeletal muscle physiology, contributing to sarcopenia. The aim of this narrative review is to provide an update on the effects of glucose-lowering drugs on sarcopenia in individuals with T2DM, focusing on the parameters used to define sarcopenia: muscle strength (evaluated by handgrip strength), muscle quantity/quality (evaluated by appendicular lean mass or skeletal muscle mass and their indexes), and physical performance (evaluated by gait speed or short physical performance battery). Furthermore, we also describe the plausible mechanisms by which glucose-lowering drugs may impact on sarcopenia.

Risk of non-vertebral fractures in men with type 2 diabetes: A systematic review and meta-analysis of cohort studies

PURPOSE

Type 2 diabetes mellitus (T2DM) is a chronic metabolic disorder. Research regarding the risk of non-vertebral fractures in men, especially in elderly men with T2DM, has not been a priority. T2DM is not a known independent risk factor for low-energy fractures in patients. We aimed to explore the relationship between men (especially older men) with T2DM and the risk of non-vertebral fractures and the reasons for the sex differences.

METHODS

The PubMed, MEDLINE, and Cochrane Library databases were searched for articles on T2DM and fracture risk. A meta-analysis, including heterogeneity testing, publication bias analysis, and subgroup analysis of the included studies, was performed using STATA software.

RESULTS

Sixteen studies involving 1,758,225 participants, 59,909 non-vertebral fracture events, and 6430 vertebral fracture events were included in this research. The adjusted relative risk of T2DM and non-vertebral fracture in men was 1.20 (95% confidence interval [CI] 1.09-1.31), implying that men with T2DM have a slightly increased risk of non-vertebral fracture.

CONCLUSION

Male patients with T2DM have a slightly increased risk of non-vertebral fractures. Due to the differences in bone strength, sex steroid hormone levels, bone quality and muscle strength and balance, men with type 2 diabetes have a lower risk of non-vertebral fractures than women.

Effectiveness and safety of low-level laser therapy in diabetic peripheral neuropathy: a protocol for a systematic review and meta-analysis

BACKGROUND

Diabetic peripheral neuropathy (DPN) is one of the most common chronic complications of diabetes mellitus. The main symptoms of DPN include numbness or pain in both extremities and paresthesia (such as formication or burning sensations), which greatly affect patients' quality of life. Pharmacological treatments for DPN are associated with both uncertain therapeutic effects and adverse effects, as well as with high costs. Some clinical studies have reported that low-level laser therapy (LLLT) relieves clinical symptoms and improves nerve function in patients with DPN. We intend to conduct a systematic review and meta-analysis to further evaluate the effectiveness and safety of LLLT for DPN.

METHODS

The following electronic databases will be searched to retrieve literature from their inception until December 2020: MEDLINE (PubMed), Embase, Cochrane Central Register of Controlled Trials, Web of Science (the Science and Social Science Citation Index), CNKI, VIP, WanFang, and SinoMed. Simultaneously, clinical registration tests and gray literature will also be retrieved. Randomized controlled trials (RCTs) comparing LLLT with either sham LLLT, no (specific) treatment, or active conventional medical treatments will be included. The primary outcomes will be nerve conduction velocity as well as clinical scores that assess neurological function and related symptoms. The risk of bias of each study and quality of evidence will be assessed using the updated Cochrane Risk of Bias 2.0 tool and GRADE approach, respectively. A meta-analysis will then be conducted using Review Manager software version 5.3.

DISCUSSION

This study will integrate RCTs and analyze data to provide a detailed summary of the evidence relating to the effects and safety of LLLT in patients with DPN. LLLT will be compared with sham LLLT, no (specific) treatment, or active conventional medical treatments, especially in terms of neurological function, quality of life, and adverse events. In conclusion, this systematic review will generate evidence regarding the use of LLLT to treat DPN, in terms of both its efficacy and safety.

SYSTEMATIC REVIEW REGISTRATION

This protocol was registered with the International Prospective Register of Systematic Reviews on April 2020 (registration number: CRD42020170625 ).

Applicability of High-Frequency Ultrasound to the Early Diagnosis of Diabetic Peripheral Neuropathy

This study investigated the applicability of high-frequency ultrasound (HFU) to the early diagnosis of diabetic peripheral neuropathy (DPN). Patients with type 2 diabetes (N = 60) were divided into diabetic nonperipheral neuropathy and DPN groups (group A and group B, respectively; n = 30 each) based on electroneurophysiologic findings. Additionally, 30 nondiabetic patients were included as the healthy control group (group C). We calculated the cross-sectional area (CSA) of the median nerve (MN) of the right upper limb at 7 different sites (MN1–7) based on measured width (W) and thickness (T). Ultrasound imaging characteristics of the MN including internal echo, internal structure, boundary, epineurium, and blood flow were recorded. The 90 subjects (51 male and 39 female) had an average age of 56.09 ± 12.66 years. W, T, and CSA of the MN were increased in group A compared to group C (with significant differences at MN1, MN4, and MN7 (P < 0.05)) and in group B compared to group C (with significant differences at all 7 levels, especially MN6 and MN7 (P < 0.05)). Receiver operating characteristic curve analysis showed that CSA at the MN7 level had the highest diagnostic accuracy for DPN in group B, with a threshold value of 12.42 mm². Ultrasound examination revealed that the MN had lost the internal sieve mesh structure and showed reduced echo, a partial blood flow signal, and thickened epineurium in patients with DPN; these findings were particularly obvious at MN6 and MN7, corresponding to the carpal tunnel. CSA was positively correlated with motor latency and F wave average latency and negatively correlated with motor conduction velocity, motor amplitude, and sensory conduction velocity in group B. Thus, HFU may be useful for the early diagnosis of DPN, which can improve clinical outcomes.

Association of obesity, diabetes, and physical frailty with dental and tongue-lip motor dysfunctions in patients with metabolic disease

OBJECTIVE

This study aimed to reveal the clinical features associated with decreased dental (or shearing/crushing) and tongue-lip motor functions in patients with metabolic diseases.

METHODS

One thousand patients with metabolic diseases including diabetes, dyslipidemia, hypertension, and hyperuricemia were recruited. Dental function was assessed with a gummy jelly test, wherein glucose elution from a chewed gummy jelly was measured. Tongue-lip motor function was measured as repeatedly pronounced syllables per second. The association of clinical variables with the two functions was analyzed using multivariate linear regression models.

RESULTS

The mean measurement of dental function was 202 ± 73 mg/dL, and that of tongue-lip motor function was 5.5 ± 1.0 times/s. Clinical variables independently associated with dental function (mg/dL) were age (adjusted regression coefficient β = -9.8 per standard deviation [SD]), smoking (β = -14.4 and -25.9 for past and current smoking, respectively), body mass index (BMI) 25-30 and ≥30 versus 20-25 kg/m² (β = -14.7 and -23.1, respectively), diabetes (β = -11.9), hemoglobin A1c level ≥64 mmol/mol (β = -14.6), gait speed (β = 6.2 per SD), and handgrip strength (β = 7.5 and 7.7 per SD for males and females, respectively) (all P < 0.05). Clinical variables independently associated with tongue-lip motor function (times/s) were age (β = -0.31 per SD), BMI ≥ 30 versus 20-25 kg/m² (β = -0.24), diabetes (β = -0.22), dyslipidemia (β = 0.16), gait speed (β = 0.12 per SD), and handgrip strength (β = 0.18 and 0.13 per SD for males and females, respectively) (all P < 0.05).

CONCLUSIONS

Obesity, diabetes, physical frailty, and old age were shared risk factors for decreased dental and tongue-lip motor functions in patients with metabolic diseases.

Not Only Diabetes but Also Prediabetes Leads to Functional Decline and Disability in Older Adults

OBJECTIVE

Diabetes is linked to functional decline, but the impact of prediabetes on physical function is unknown. We aimed to examine and compare the impact of prediabetes and diabetes on physical function and disability progression and to explore whether cardiovascular diseases (CVDs) mediate these associations.

RESEARCH DESIGN AND METHODS

A cohort of 2,013 participants aged ≥60 from the Swedish National Study on Aging and Care in Kungsholmen, an ongoing population-based longitudinal study, was monitored for up to 12 years. Physical function was measured with chair stand (s) and walking speed (m/s) tests, and disability was measured by summing the numbers of impaired basic and instrumental activities of daily living. Diabetes was identified through medical examinations or clinical records, medication use, or glycated hemoglobin (HbA_1c) ≥6.5%. Prediabetes was defined as HbA_1c ≥5.7-6.4% in participants free of diabetes. CVDs were ascertained through clinical examinations and the National Patient Register. Data were analyzed using mixed-effect models and mediation models.

RESULTS

At baseline, 650 (32.3%) had prediabetes and 151 had diabetes (7.5%). In multiadjusted mixed-effect models, prediabetes was associated with an increased chair stand time (β 0.33, 95% CI 0.05-0.61), a decreased walking speed (β -0.006, 95% CI -0.010 to -0.002), and an accelerated disability progression (β 0.05, 95% CI 0.01-0.08), even after controlling for the future development of diabetes. Diabetes led to faster functional decline than prediabetes. In mediation analyses, CVDs mediated 7.1%, 7.8%, and 20.9% of the associations between prediabetes and chair stand, walking speed, and disability progression, respectively.

CONCLUSIONS

Prediabetes, in addition to diabetes, is associated with faster functional decline and disability, independent of the future development of diabetes. This association may be in part mediated by CVDs.

Simultaneous T1 , T2 , and T1ρ relaxation mapping of the lower leg muscle with MR fingerprinting

PURPOSE

To develop a novel MR-fingerprinting (MRF) pulse sequence that is insensitive to B 1 + and B₀ imperfections for simultaneous T₁ , T₂ , and T_1ρ relaxation mapping.

METHODS

We implemented a totally balanced spin-lock (TB-SL) module to encode T_1ρ relaxation into an existing MRF framework that encoded T₁ and T₂ . The spin-lock module used two 180° pulses with compensatory phases to reduce T_1ρ sensitivity to B₁ and B₀ inhomogeneities. We compared T_1ρ measured using TB-SL MRF in Bloch simulations, model agar phantoms, and in vivo experiments to those with a self-compensated spin-lock preparation module (SC-SL). The TB-SL MRF repeatability was evaluated in maps acquired in the lower leg skeletal muscle of 12 diabetic peripheral neuropathy patients, scanned two times each during visits separated by about 30 days.

RESULTS

The phantom relaxation times measured with TB-SL and SC-SL MRF were in good agreement with reference values in regions with low B₁ inhomogeneities. Compared with SC-SL, TB-SL MRF showed in experiments greater robustness against severe B₁ inhomogeneities and in Bloch simulations greater robustness against B₁ and B₀ . We measured with TB-SL MRF an average T₁ = 950.1 ± 28.7 ms, T₂ = 26.0 ± 1.2 ms, and T_1ρ = 31.7 ± 3.2 ms in skeletal muscle across patients. Bland-Altman analysis demonstrated low bias between TB-SL and SC-SL MRF and between TB-SL MRF maps acquired in two visits. The coefficient of variation was less than 3% for all measurements.

CONCLUSION

The proposed TB-SL MRF sequence is fast and insensitive to B 1 + and B₀ imperfections. It can simultaneously map T₁ , T₂ , T_1ρ , and B 1 + in a single scan and can potentially be used to study muscle composition.

Association between diabetic neuropathy and osteoporosis in patients: a systematic review and meta-analysis

OBJECTIVES

Many studies have explored the association between neuropathy and osteoporosis in patients with diabetes mellitus. However, the results still remain inconsistent and controversial. We aimed to estimate the association between diabetic neuropathy and osteoporosis.

METHODS

Databases, including PubMed, Embase, Web of Science, the Cochrane library, Chinese Biomedical Literature Database (CBM), and Wanfang, were screened from inception to 30 March 2020. Studies were selected and data were extracted by two independent reviewers. Study characteristics and quality sections were reviewed independently. Pooled ORs and 95% CIs were calculated using random effects model when evidence of heterogeneity was present; otherwise, fixed effects model was used. Meta-regression and subgroup analyses were performed to explore the source of heterogeneity. Sensitivity analysis and publication bias were also tested.

RESULTS

A total of 11 studies with 27,585 participants were included in this analysis which indicated that there was an increased odd between diabetic neuropathy and osteoporosis (overall OR 2.20, 95% CI 1.71-2.83). In the subgroup analyses and meta-regression, diabetic neuropathy has no significant difference in osteoporosis or fracture (p = 0.532). And osteoporosis also has no significant difference in type 1 or type 2 diabetic neuropathy (p = 0.668).

CONCLUSIONS

This meta-analysis suggests that patients with diabetic neuropathy have a significantly increased chance of developing osteoporosis, even fragility fracture. The clinicians should pay more attention to the patients with diabetic neuropathy. Further studies were still needed to explore the confounding factors among studies and to elucidate the underlying biological mechanisms.

Impact of lower limb muscle strength on walking function beyond aging and diabetes

Objective

This study was performed to investigate the influence of lower limb muscle strength on the walking function of advanced-age patients with diabetes.

Methods

In this cross-sectional descriptive study, data were collected from 202 advanced-age patients with diabetes. All patients completed questionnaires, the one-leg stance test, the timed up-and-go test, the 30-s sit-to-stand test, and plantar pressure platform measurements. The patients were divided in two groups according to their lower limb muscle strength: those with declining muscle strength and those with normal muscle strength.

Results

Walking function was significantly abnormal in the patients with declining lower limb muscle strength. The gait trajectories were abnormal, mainly with respect to a shortage of driving force.

Conclusion

The lower limb muscle strength can affect the static balance and dynamic balance in advanced-age patients with declining lower limb muscle strength.

Linear mixed-effects models for the analysis of high-density electromyography with application to diabetic peripheral neuropathy

This article demonstrates the power and flexibility of linear mixed-effects models (LMEMs) to investigate high-density surface electromyography (HD-sEMG) signals. The potentiality of the model is illustrated by investigating the root mean squared value of HD-sEMG signals in the tibialis anterior muscle of healthy (n = 11) and individuals with diabetic peripheral neuropathy (n = 12). We started by presenting the limitations of traditional approaches by building a linear model with only fixed effects. Then, we showed how the model adequacy could be increased by including random effects, as well as by adding alternative correlation structures. The models were compared with the Akaike information criterion and the Bayesian information criterion, as well as the likelihood ratio test. The results showed that the inclusion of the random effects of intercept and slope, along with an autoregressive moving average correlation structure, is the one that best describes the data (p < 0.01). Furthermore, we demonstrate how the inclusion of additional variance structures can accommodate heterogeneity in the residual analysis and therefore increase model adequacy (p < 0.01). Thus, in conclusion, we suggest that adopting LMEM to repeated measures such as electromyography can provide additional information from the data (e.g. test for alternative correlation structures of the RMS value), and hence provide new insights into HD-sEMG-related work.

Association of sarcopenia and muscle mass with both peripheral neuropathy and nerve function in patients with type 2 diabetes

AIM

This study aimed to investigate the association of sarcopenia and muscle mass with both peripheral neuropathy and nerve function in type 2 diabetes mellitus.

METHODS

A total of 1794 patients (937 men and 857 women) with type 2 diabetes, with a mean age of 60.22 years, were enrolled for a cross-sectional study; of these, 183 patients were enrolled for a follow-up study with a median follow-up of 2.7 years. All participants underwent nerve conduction studies and muscle mass index (ASM/HT²) measurements. The composite Z scores for the sensory nerve conduction velocity (SCV) and the motor nerve conduction velocity (MCV) were calculated. The changes in ASM/HT², SCV, and MCV were calculated from the measurements nearly 2 years apart and classified into three groups: a decrease in ASM/HT² of >3%, a minor change within ±3%, and an increase in ASM/HT² of >3%.

RESULTS

The ASM/HT² of men was positively associated with the composite Z scores of MCV and SCV, and sarcopenia highly correlated with DPN after adjusting for confounding factors. The optimal cutoff point for ASM/HT² that indicated DPN was 7.09 kg/m². Furthermore, increases in ASM/HT² independently predicted a greater benefit of MCV and SCV increment outcomes, whereas a minor change in ASM/HT² only significantly associated with lower benefit in terms of SCV increment. However, this phenomenon was not observed in women.

CONCLUSIONS

Sarcopenia and DPN exhibited a close association. The increased muscle mass improved the partial MCVs and SCVs. However, a sex-related discrepancy was observed in this phenomenon.

Hand and foot exercises for diabetic peripheral neuropathy: A randomized controlled trial

Exercises for diabetic peripheral neuropathy remain controversial, especially with regard to recommended precautions and weightbearing exercises for individuals. We aimed to investigate the effect of 8 weeks of simple hand, finger, and foot exercises in patients with diabetic peripheral neuropathy. After randomization, exercise (n = 51) and control (n = 53) groups received usual care and diabetic foot care education; only the exercise group performed exercises. Primary outcomes, including activities of daily living (assessed using the Patient Neurotoxicity Questionnaire), neuropathy severity (monofilament and vibration test), and pain (behavioral rating scale and Visual Analog Scale), and secondary outcomes, including physical function of the hand and foot (grip, pinch, finger counting time, and Timed Up and Go tests), were assessed at baseline, after the 8-week intervention, and at the 16-week follow-up. The exercise group showed significantly stronger improvements in motor score and specific activities of daily living, such as climbing stairs and performing work or chores. Our exercises can be used to improve limb function in patients with diabetic neuropathy.

Quantification of Mitochondrial Oxidative Phosphorylation in Metabolic Disease: Application to Type 2 Diabetes

Type 2 diabetes (T2D) is a growing health concern with nearly 400 million affected worldwide as of 2014. T2D presents with hyperglycemia and insulin resistance resulting in increased risk for blindness, renal failure, nerve damage, and premature death. Skeletal muscle is a major site for insulin resistance and is responsible for up to 80% of glucose uptake during euglycemic hyperglycemic clamps. Glucose uptake in skeletal muscle is driven by mitochondrial oxidative phosphorylation and for this reason mitochondrial dysfunction has been implicated in T2D. In this review we integrate mitochondrial function with physiologic function to present a broader understanding of mitochondrial functional status in T2D utilizing studies from both human and rodent models. Quantification of mitochondrial function is explained both in vitro and in vivo highlighting the use of proper controls and the complications imposed by obesity and sedentary lifestyle. This review suggests that skeletal muscle mitochondria are not necessarily dysfunctional but limited oxygen supply to working muscle creates this misperception. Finally, we propose changes in experimental design to address this question unequivocally. If mitochondrial function is not impaired it suggests that therapeutic interventions and drug development must move away from the organelle and toward the cardiovascular system.

Peripheral Neuropathy as a Component of Skeletal Disease in Diabetes

PURPOSE OF REVIEW

The goal of this review is to explore clinical associations between peripheral neuropathy and diabetic bone disease and to discuss how nerve dysfunction may contribute to dysregulation of bone metabolism, reduced bone quality, and fracture risk.

RECENT FINDINGS

Diabetic neuropathy can decrease peripheral sensation (sensory neuropathy), impair motor coordination (motor neuropathy), and increase postural hypotension (autonomic neuropathy). Together, this can impair overall balance and increase the risk for falls and fractures. In addition, the peripheral nervous system has the potential to regulate bone metabolism directly through the action of local neurotransmitters on bone cells and indirectly through neuroregulation of the skeletal vascular supply. This review critically evaluates existing evidence for diabetic peripheral neuropathy as a risk factor or direct actor on bone disease. In addition, we address therapeutic and experimental considerations to guide patient care and future research evaluating the emerging relationship between diabetic neuropathy and bone health.