Prevalence of diabetic peripheral neuropathy and its relation to glycaemic control and potential risk factors: the EURODIAB IDDM Complications Study

The association between renal function and neurological diseases in type 2 diabetes: a multicenter nationwide cross-sectional study

BACKGROUND

The evidence for an association between renal function and neurological diseases among type 2 diabetes mellitus (T2DM) patients, particularly in the Asian population, is limited. This study aimed to assess the association between glomerular filtration rate (GFR) and various neurological diseases among T2DM patients in Thailand using a nationwide patient sample.

METHODS

We conducted a nationwide cross-sectional study based on the DM/HT study of the Medical Research Network of the Consortium of Thai Medical Schools. This study evaluated adult T2DM patients receiving care at public Thailand hospitals in the year 2014. GFR was categorized into ≥60, 30-59, and < 30 mL/min/1.73 m². Neurological diseases studied included ischemic stroke/transient ischemic attack (TIA), hemorrhagic stroke, dementia, all cerebrovascular disease, and peripheral neuropathy. Multivariate logistic regression was performed to assess the association between GFR and neurological diseases.

RESULTS

A total of 30,423 T2DM patients with available GFR data were included in the analysis. The mean GFR was 68.18 ± 26.45 mL/min/1.73 m². The prevalence of ischemic stroke/TIA, hemorrhagic stroke, dementia, any cerebrovascular diseases and peripheral neuropathy were 2.9%, 0.3%, 0.1%, 3.2%, and 3.1%, respectively. Patients with GFR of 30-59 and <30 mL/min/1.73 m² were significantly associated with increased rates of ischemic stroke/TIA, any cerebrovascular diseases, and peripheral neuropathy when compared with patients with GFR of ≥60 mL/min/1.73 m². This association remained significant after adjustment for potential confounders.

CONCLUSION

Decreased GFR was associated with increased ischemic stroke/TIA, all cerebrovascular diseases, and peripheral neuropathy. GFR should be monitored in diabetic patients for neurological disease awareness and prevention.

Prevalence of Diabetic Neuropathy in Young Adults with Type 1 Diabetes and the Association with Insulin Pump Therapy

AIMS

The aim was to investigate the prevalence of diabetic sensorimotor polyneuropathy (DSPN) and cardiovascular autonomic neuropathy (CAN) in a Danish population of young adults with type 1 diabetes (T1D) using both established and novel measuring modalities. Furthermore, to investigate the association between continuous subcutaneous insulin infusion (CSII) treatment and these complications.

MATERIALS AND METHODS

CAN was assessed by cardiovascular autonomic reflex tests. DSPN was assessed not only by perception of light touch and pain, vibration perception threshold (VPT), Brief Pain Inventory (BPI), and Michigan Neuropathy Screening Instrument questionnaires but also by novel modalities: electrochemical skin conductance (ESC), sural nerve conduction velocity (SNCV), and sural nerve amplitude potential (SNAP).

RESULTS

The study comprised 156 young adults with a mean age of 22 years (standard deviation 1.6). The prevalence of CAN and early CAN was 9% and 28.1%, respectively. Subclinical DSPN was 55.1% and confirmed DSPN was 2.6%. Prevalence of abnormal SNAP was 23.8%, SNCV was 37.1%, ESC on the hands and feet was 4% and 8%, respectively, VPT was 1.3%, and BPI questionnaire was 1.9%. No association was found between CSII treatment and the measures of DSPN and CAN.

CONCLUSION

DSPN and CAN are prevalent in young adults with T1D with no association found with CSII treatment. The use of novel measuring modalities identified a higher number of subjects with DSPN compared with established measures. Screening for diabetic neuropathy in young adults may be beneficial to detect and prevent nerve damages at early stages.

Prostaglandin E1 plus methylcobalamin combination therapy versus prostaglandin E1 monotherapy for patients with diabetic peripheral neuropathy: A meta-analysis of randomized controlled trials

BACKGROUND

Prostaglandin E1 (P) or methylcobalamin (M) treatment has been suggested as a therapeutic approach for diabetic peripheral neuropathy (DPN) in many clinical trial reports. However, the combined effects of 2 drugs still remain dubious.

OBJECTIVE

The aim of this report was to evaluate the efficacy of M plus P (M + P) for the treatment of DPN compared with that of P monotherapy, in order to provide a reference resource for rational drug use.

METHODS

Randomized controlled trials (RCTs) of M + P for DPN published up to September 2017 were searched. Risk ratio (RR), mean difference (MD), and 95% confidence interval (CI) were calculated and heterogeneity was assessed with the I test. Subgroup and sensitivity analyses were also performed. The outcomes measured were as follows: the clinical efficacy, median motor nerve conduction velocities (MNCV), median sensory nerve conduction velocity (SNCV), peroneal MNCV, peroneal SNCV, and adverse effects.

RESULTS

Sixteen RCTs with 1136 participants were included. Clinical efficacy of M + P combination therapy was significantly better than P monotherapy (fifteen trials; RR 1.25, 95% CI 1.18-1.32, P < .00001, I = 27%). Compared with P monotherapy, the pooled effects of M + P combination therapy on nerve conduction velocity were (MD 6.29, 95% CI 4.63-7.94, P < .00001, I = 90%) for median MNCV, (MD 5.68, 95% CI 3.53-7.83, P < .00001, I = 94%) for median SNCV, (MD 5.36, 95% CI 3.86-6.87, P < .00001, I = 92%) for peroneal MNCV, (MD 4.62, 95% CI 3.48-5.75, P < .00001, I = 86%) for peroneal SNCV. There were no serious adverse events associated with drug intervention.

CONCLUSIONS

M + P combination therapy was superior to P monotherapy for improvement of neuropathic symptoms and NCVs in DPN patients. Moreover, no serious adverse events occur in combination therapy.

A new look at painful diabetic neuropathy

The prevalence of diabetes mellitus and its chronic complications continue to increase alarmingly. Consequently, the massive expenditure on diabetic distal symmetrical polyneuropathy (DSPN) and its sequelae, will also likely rise. Up to 50% of patients with diabetes develop DSPN, and about 20% develop neuropathic pain (painful-DSPN). Painful-DSPN can cast a huge burden on sufferers' lives with increased rates of unemployment, mental health disorders and physical co-morbidities. Unfortunately, due to limited understanding of the mechanisms leading to painful-DSPN, current treatments remain inadequate. Recent studies examining the pathophysiology of painful-DSPN have identified maladaptive alterations at the level of both the peripheral and central nervous systems. Additionally, genetic studies have suggested that patients with variants of voltage gated sodium channels may be more at risk of developing neuropathic pain in the presence of a disease trigger such as diabetes. We review the recent advances in genetics, skin biopsy immunohistochemistry and neuro-imaging, which have the potential to further our understanding of the condition, and identify targets for new mechanism based therapies.

Presence of chronic diabetic foot ulcers is associated with more frequent and more advanced retinopathy

AIMS

To clarify the frequency and severity of diabetic retinopathy in a group of people with Type 2 diabetes and chronic diabetic foot ulcers, and to compare visual acuity, levels of retinopathy and clinical significant macular oedema with a matched control group of people with Type 2 diabetes without a history of chronic diabetic foot ulcers.

METHODS

Visual acuity and fundus imaging were evaluated in 90 white people with at least 3 months' duration of full-thickness diabetic foot ulcers below the ankle and the results compared with those in 180 white people with Type 2 diabetes without a history of chronic diabetic foot ulcers (control group). Controls were matched for age, sex and duration of diabetes.

RESULTS

Despite similar age and diabetes duration, severe non-proliferative or proliferative diabetic retinopathy was present in 41% of the people in the diabetic foot ulcer group as compared to 15% in the control group (P<0.001). Only 6% in the diabetic foot ulcer group was without any diabetic retinopathy as compared to 34% among controls. Proliferative diabetic retinopathy was more common in the diabetic foot ulcer group (31% vs 8%; P<0.001), but time-to-proliferative diabetic retinopathy did not differ between groups. Clinically significant macular oedema was more frequently present, and the diabetic foot ulcer group exhibited significantly worse results in best and worst eye visual acuity testing.

CONCLUSIONS

In this northern European setting almost all people with Type 2 diabetes and chronic diabetic foot ulcers had diabetic retinopathy. Almost one-third had proliferative diabetic retinopathy as compared to <10% in our matched control group. More advanced diabetic retinopathy was linked to worse visual acuity.

Diabetic Neuropathy Prevalence and Its Associated Risk Factors in Two Representative Groups of Type 1 and Type 2 Diabetes Mellitus Patients from Bihor County

BACKGROUND

Diabetic neuropathy has an important impact on the quality of life of affected individuals due to the presence of chronic symptoms like distal neuropathic pain, but it also influences the survival of diabetic patients, given that the clinical forms of diabetic neuropathy produce complications such as diabetic foot syndrome in distal peripheral neuropathy or life threatening arrhythmias in autonomic cardiac neuropathy. The prevalence of diabetic neuropathy in representative cohorts is very discordant in numerous studies, and our purpose was to evaluate the frequency of this microvascular complication in Bihor County and to determine some risk factors for its development in order to perform a more rigorous screening in certain risk groups.

MATERIAL AND METHODS

We formed two representative cohorts for type 1 and type 2 diabetes mellitus population in our county and applied a questionnaire with three subsets of questions for sensitive, motor and autonomic symptoms. Every patient was evaluated by using semi quantitative tests for distal neuropathy and two tests for determination of cardiac autonomic neuropathy.

RESULTS

The prevalence of diabetic neuropathy was 28.70% in patients with type 1 diabetes mellitus and 50.70% in those with type 2 diabetes mellitus. Distal neuropathy was the most frequent clinical form, autonomic neuropathy having a low prevalence. The same risk factors were associated (p<0.01) with an increased risk of diabetic neuropathy in both type 1 and type 2 diabetes mellitus: age, diabetes duration, HbA1 c, hypertension, dyslipidaemia, and other microvascular complications.

CONCLUSION

Screening for distal symmetric polyneuropathy can be easily done by using a symptom questionnaire and semi quantitative tests, and it is important to consider the fact that over 50% of type 2 diabetes patients in the representative cohort were affected by the complication. Control of modifiable risk factors can reduce the risk of neuropathy development considering the lower frequency of neuropathy in the groups with good glycaemic control, normal blood pressure and absence of dyslipidaemia.

Cognitive function in early and later life is associated with blood glucose in older individuals: analysis of the Lothian Birth Cohort of 1936

AIMS/HYPOTHESIS

The aim of this study was to examine whether cognitive function in early and later life, and decline in cognitive function from age 70 to 79 years, are associated with high blood glucose, as measured by HbA1c, at baseline (age 70), and changes in blood glucose from age 70 to 79.

METHODS

Participants (n = 1091) in the Lothian Birth Cohort of 1936 were examined. Fourteen tests were used to assess cognitive functions, grouped into four domains: visuospatial ability, processing speed, memory and crystallised ability. Test results, and measurements of HbA1c and other health variables, were collected at each of four waves of assessment: at the mean age of 70, 73, 76 and 79 years. Data on cognitive function at age 11 was also available for this cohort. Latent growth curve modelling was performed and statistical controls for known risk factors were introduced.

RESULTS

Higher age 11 cognitive function predicted lower HbA1c level at age 70 (p < 0.001). Higher cognitive function at age 70 was related to a comparatively smaller increase in HbA1c levels from age 70 to 79 (p < 0.001). HbA1c from age 70 to 79 did not have any consistent association with change in cognitive function from age 70 to 79. These associations survived adjustments for age, sex, education, APOE*ε4, smoking history, cardiovascular disease history, hypertension history, BMI and corrections for multiple testing.

CONCLUSIONS/INTERPRETATION

Our results show that, among older individuals, high blood glucose is consistently predicted by lower cognitive function. Clinical care that examines and tracks cognitive function, while also taking the positive effects of maintaining cognitive function and emulating healthy behaviours associated with higher cognitive function into account, may be one approach for protecting at-risk individuals from elevated blood glucose and subsequent type 2 diabetes mellitus.

Update on the Management of Diabetic Neuropathy

IN BRIEF Distal symmetric polyneuropathy (DSPN) and diabetic autonomic neuropathies, particularly cardiovascular autonomic neuropathy (CAN), are prevalent diabetes complications with high morbidity, mortality, and amputation risks. The diagnosis of DSPN is principally a clinical one based on the presence of typical symptoms combined with symmetrical, distal-to-proximal stocking-glove sensory loss. CAN is an independent risk factor for cardiovascular mortality, arrhythmia, silent ischemia, major cardiovascular events, and myocardial dysfunction. Screening for CAN in high-risk patients is recommended. Symptoms of gastroparesis are nonspecific and do not correspond with its severity. Diagnosis of gastroparesis should exclude other factors well documented to affect gastric emptying such as hyperglycemia, hypoglycemia, and certain medications. There is a lack of treatment options targeting the neuropathic disease state. Managing neuropathic pain also remains a challenge. Given the high risk of addiction, abuse, psychosocial issues, and mortality, opioids are not recommended as first-, second-, or third-line agents for treating painful DSPN.

Fasudil combined with methylcobalamin or lipoic acid can improve the nerve conduction velocity in patients with diabetic peripheral neuropathy: A meta-analysis

BACKGROUND

Fasudil (F) plus methylcobalamin (M) or lipoic acid (L) treatment has been suggested as a therapeutic approach for diabetic peripheral neuropathy (DPN) in numerous studies. However, the effect of the combined use still remains dubious.

OBJECTIVE

The aim of this report was to evaluate the efficacy of F plus M or L (F + M or F + L) for the treatment of DPN compared with that of M or L monotherapy, respectively, in order to provide the basis and reference for clinical rational drug use.

METHODS

Randomized controlled trials (RCTs) of F for DPN published up to September 2017 were searched. Relative risk (RR), mean difference (MD), and 95% confidence interval (CI) were calculated and heterogeneity was assessed with the I test. Sensitivity analyses were also performed. The outcomes measured were as follows: the clinical efficacy, median motor nerve conduction velocities (NCVs) (MNCVs), median sensory NCV (SNCV), peroneal MNCV, peroneal SNCV, and adverse effects.

RESULTS

Thirteen RCTs with 1148 participants were included. Clinical efficacy of F + M combination therapy was significantly better than M monotherapy (8 trials; RR 1.26, 95% CI 1.17-1.35, P < .00001, I = 0%), the efficacy of F + L combination therapy was also obviously better than L monotherapy (4 trials; RR 1.27, 95% CI 1.16-1.39, P < .00001, I = 0%). Compared with monotherapy, the pooled effects of combination therapy on NCV were (MD 6.69, 95% CI 4.74-8.64, P < .00001, I = 92%) for median MNCV, (MD 6.71, 95% CI 1.77-11.65, P = .008, I = 99%) for median SNCV, (MD 4.18, 95% CI 2.37-5.99, P < .00001, I = 94%) for peroneal MNCV, (MD 5.89, 95% CI 3.57-8.20, P < .00001, I = 95%) for peroneal SNCV. Furthermore, there were no serious adverse events associated with drug intervention.

CONCLUSION

Combination therapy with F plus M or L was superior to M or L monotherapy for improvement of neuropathic symptoms and NCVs in DPN patients, respectively. Moreover, no serious adverse events occur in combination therapy.

Feasibility and effectiveness of electrochemical dermal conductance measurement for the screening of diabetic neuropathy in primary care. DECODING Study (Dermal Electrochemical Conductance in Diabetic Neuropathy). Rationale and design

Diabetes mellitus is the leading cause of polyneuropathy in the Western world. Diabetic neuropathy is a frequent complication of diabetes and may have great clinical transcendence due to pain and possible ulceration of the lower extremities. It is also a relevant cause of morbidity and mortality in patients with diabetes. Although the cause of polyneuropathy in patients with diabetes is only partially known, it has been associated with chronic hyperglycemia suggesting the possible etiopathogenic implication of advanced glycosylation end products. The strategy of choice in the medical management of diabetic neuropathy is early detection since glycaemic control and the use of certain drugs may prevent or slow the development of this disease. Diabetic neuropathy most often presents with a dysfunction of unmyelinated C-fibers, manifested as an alteration of the sweat reflex of the eccrine glands. This dysfunction can now be demonstrated using a newly developed technology which measures dermal electrochemical conductivity. This noninvasive test is easy and cost-effective. The aim of the present study is to evaluate the feasibility and effectiveness of dermal electrochemical conductance measurement (quantitative expression of the sudomotor reflex) as a screening test for the diagnosis of diabetic neuropathy in patients in primary care.

Clinical correlates of sudomotor dysfunction in patients with type 2 diabetes and peripheral neuropathy

AIMS

To investigate the factors associated with abnormal electrochemical skin conductance (ESC) in patients with type 2 diabetes mellitus (T2D) and early diabetic peripheral neuropathy (DPN).

METHODS

We recruited 523 consecutive patients with T2D (median age: 50 [interquartile range: 16] years; median T2D duration: 4 [5] years). Sudomotor dysfunction was defined as an ESC <60 µS, and DPN as a neuropathy disability score (NDS) ≥6. Logistic regression was performed to determine the predictors of sudomotor dysfunction in patients with DPN.

RESULTS

The prevalence of sudomotor dysfunction was 29% for all patients and 84.5% for patients with DPN. A significant negative correlation was observed between the NDS and ESC measurements (r = -0.52, p < 0.0001). In the univariate analysis, abnormal ESC measures were associated with age, diabetes duration, glycated hemoglobin, diabetic retinopathy, insulin therapy, and foot abnormalities. In the multivariate analysis, ESC abnormalities were associated with age, diabetes duration, glycated hemoglobin levels, insulin therapy, and foot deformities. There was a robust association between foot deformities and abnormal ESC (p = 0.049; odds ratio = 16.02) in patients with DPN.

CONCLUSION

Sudomotor dysfunction is highly prevalent in patients with T2D, especially in those with DPN. Various diabetes-related factors were linked to lower ESC values, indicating an association between chronic hyperglycemia and sudomotor function. We also observed a strong relationship between foot deformities and ESC abnormalities. We conclude that the factors associated with DPN are also relevant to sudomotor dysfunction.

Expression of macrophage migration inhibitory factor in footpad skin lesions with diabetic neuropathy

Background

Diabetic neuropathy originating in distal lower extremities is associated with pain early in the disease course, overwhelming in the feet. However, the pathogenesis of diabetic neuropathy remains unclear. Macrophage migration inhibitory factor has been implicated in the onset of neuropathic pain and the development of diabetes. Objective of this study was to observe pain syndromes elicited in the footpad of diabetic neuropathy rat model and to assess the contributory role of migration inhibitory factor in the pathogenesis of diabetic neuropathy.

Methods

Diabetic neuropathy was made in Sprague Dawley rats by streptozotocin. Pain threshold was evaluated using von Frey monofilaments for 24 weeks. On comparable experiment time after streptozotocin injection, all footpads were prepared for following procedures; glutathione assay, terminal deoxynucleotidyl transferase-mediated biotinylated UTP nick end labeling staining, immunohistochemistry staining, real-time reverse transcription polymerase chain reaction, and Western blot. Additionally, human HaCaT skin keratinocytes were treated with methylglyoxal, transfected with migration inhibitory factor/control small interfering RNA, and prepared for real-time reverse transcription polymerase chain reaction and Western blot.

Results

As compared to sham group, pain threshold was significantly reduced in diabetic neuropathy group, and glutathione was decreased in footpad skin, simultaneously, cell death was increased. Over-expression of migration inhibitory factor, accompanied by low expression of glyoxalase-I and intraepidermal nerve fibers, was shown on the footpad skin lesions of diabetic neuropathy. But, there was no significance in expression of neurotransmitters and inflammatory mediators such as transient receptor potential vanilloid 1, mas-related G protein coupled receptor D, nuclear factor kappa B, tumor necrosis factor-alpha, and interleukin-6 between diabetic neuropathy group and sham group. Intriguingly, small interfering RNA-transfected knockdown of the migration inhibitory factor gene in methylglyoxal-treated skin keratinocytes increased expression of glyoxalase-I and intraepidermal nerve fibers in comparison with control small interfering RNA-transfected cells, which was decreased by induction of methylglyoxal.

Conclusions

Our findings suggest that migration inhibitory factor can aggravate diabetic neuropathy by suppressing glyoxalase-I and intraepidermal nerve fibers on the footpad skin lesions and provoke pain. Taken together, migration inhibitory factor might offer a pharmacological approach to alleviate pain syndromes in diabetic neuropathy.

Clustering of microvascular complications in Type 1 diabetes mellitus

AIMS

To describe to what extent microvascular complications exhibit clustering in persons with Type 1 diabetes, and to assess whether the presence of one complication modified the strength of the association between the other two.

METHODS

We conducted a cross-sectional analysis of the electronic medical records of 2276 persons with Type 1 diabetes treated in a specialized care hospital in Denmark in 2013. We used log-linear analysis to describe associations between diabetic kidney disease, neuropathy and retinopathy and logistic regression models to quantify the magnitude of associations adjusting for potential confounders.

RESULTS

The median duration of diabetes was 24 years and median HbA1c was 63 mmol/mol (7.9%). We found strong indication of clustering and found no evidence that presence of one complication modified the association between the other two. In models adjusted for diabetes duration and HbA_1c, persons with neuropathy had an OR of 2.15 (95% CI: 1.73-2.66) for concurrent diabetic kidney disease. Those with retinopathy had an OR of 2.49 (1.92-3.24) for diabetic kidney disease and of 2.66 (1.94-3.64) for neuropathy.

CONCLUSIONS

Microvascular complications in persons with Type 1 diabetes exhibit strong clustering. However, the association between any pair of complications is not modified by the presence of the third.

Glycaemic indices and haemoglobin A1c as predictors for non-healing ulcers

OBJECTIVE

Non-healing lower extremity ulcers (NHLU) are a common podiatric complication of diabetes, with poor glycaemic control as a risk factor for development. Glycaemic indices, such as haemoglobin A1c (HbA1c) and fasting plasma glucose (FPG), are used to diagnose and to monitor diabetes. Using a population-based, nationally representative sample, we evaluate the relationship between glycaemic indices and NHLU (as defined by the patient) to propose glycaemic thresholds for clinical suspicion of patient NHLU status.

METHOD

Using data from the 1999-2004 National Health and Nutrition Examination Surveys (NHANES), a total of 9769 adults (≥40 years old) with available self-reported diabetes and NHLU status were analysed. Glycaemic index markers, including FPG and HbA1c, were assessed via laboratory analysis from serum blood samples. Logistic regression models were fitted to determine optimal thresholds for FPG and HbA1c to predict NHLU status.

RESULTS

Compared with those without NHLU, NHLU patients were older, male, had higher rates of diabetes, were more likely to take insulin, and had lower total cholesterol. Youden's Index for NHLU identified the optimal FPG threshold as 117.7mg/dl (sensitivity: 33.5%; specificity: 82.6%). The optimal HbA1c threshold was 5.9% (sensitivity: 43.2%; specificity: 77.3%). HbA1c (Odds ratio (OR) 2.44, 95% Confidence Interval (CI) 1.96-3.05; Area under curve (AUC) 0.62) was a stronger discriminator of NHLU compared to FPG (OR 2.19; 95%CI 1.57-3.05; AUC 0.60).

CONCLUSION

This study identified glycaemic thresholds for suspicion of NHLU development that are lower than the glucose goal levels recommended as optimal by the American Diabetes Association. Health professionals should be aware of these glycaemic indices when screening patients with diabetes for NHLU. Future longitudinal and validation studies are necessary to better discern the ideal glycaemic index thresholds to identify NHLU.

Genetic studies of human neuropathic pain conditions: a review

Numerous studies have shown associations between genetic variants and neuropathic pain disorders. Rare monogenic disorders are caused by mutations of substantial effect size in a single gene, whereas common disorders are likely to have a contribution from multiple genetic variants of mild effect size, representing different biological pathways. In this review, we survey the reported genetic contributors to neuropathic pain and submit them for validation in a 150,000-participant sample of the U.K. Biobank cohort. Successfully replicated association with a neuropathic pain construct for 2 variants in IL10 underscores the importance of neuroimmune interactions, whereas genome-wide significant association with low back pain (P = 1.3e-8) and false discovery rate 5% significant associations with hip, knee, and neck pain for variant rs7734804 upstream of the MAT2B gene provide evidence of shared contributing mechanisms to overlapping pain conditions at the molecular genetic level.

Factors associated with distal symmetric polyneuropathies in adult Zambians: A cross-sectional, observational study of the role of HIV, non-antiretroviral medication exposures, and nutrition

BACKGROUND

Non-antiretroviral (ART) drug exposures and poor nutrition may be important modifiable risk factors for distal symmetric polyneuropathies (DSP) in sub-Saharan Africa.

METHODS

We conducted a cross-sectional study of DSP prevalence and factors associated with DSP among clinic attendees in urban and rural Zambia. All participants underwent neurologist-performed examination. Laboratory investigations seeking comorbid risk factors for DSP were performed for DSP cases.

RESULTS

We identified 31/137 (22.6%) HIV+ and 21/177 (11.9%) HIV- DSP cases. DSP prevalence did not differ by urbanicity, although rural participants were significantly more likely to have one asymptomatic DSP sign. Low dietary diversity, history of syphilis, history of tuberculosis, and prior metronidazole and ciprofloxacin use were associated with DSP amongst HIV+ cases, while age and education were associated with DSP in HIV- participants (all p-values < 0·05). In a multivariate logistic regression model, HIV (p = 0·0001) and age (p < 0·0001), and ciprofloxacin exposure (p = 0·01) remained independently associated with DSP. While diabetes was rare, supoptimal micronutrients levels were common among DSP cases regardless of HIV status.

CONCLUSIONS

While HIV infection is strongly associated with DSP in Zambia, history of non-ART drug exposures and low dietary diversity are also important determinants of DSP in HIV+ individuals. Treatable micronutrient deficiencies were common.

[Alpha-lipoic acid in the treatment of diabetic polyneuropathy]

The issues of classification, pathogenesis, pathomorphology and treatment of diabetic polyneuropathy (DPN) are addressed. Pathogenetic mechanisms of the action of alpha-lipoic acid in treatment of DPN are justified. The authors present the results of randomized placebo-controlled trials of alpha-lipoic acid that revealed the high clinical efficacy and absence of side-effects even during the long-term treatment.

Lower gastrointestinal symptoms are associated with worse glycemic control and quality of life in type 1 diabetes mellitus

OBJECTIVES

Lower gastrointestinal symptoms are not well characterized in people with type 1 diabetes, and the effects on quality of life and glycemic control are unknown. This study aimed to determine the prevalence of lower gastrointestinal symptoms and the effects on glycemic control and quality of life, and to investigate for underlying causes.

RESEARCH DESIGN AND METHODS

This is a prospective, cohort study in secondary care. Patients with type 1 diabetes completed a gastrointestinal symptom questionnaire and the Short Form 36 V.2 quality of life questionnaire and had their hemoglobin A1c measured. Patients with diarrhea were offered reassessment and investigation as per the national guidelines. Controls without diabetes were used to compare symptom prevalence and quality of life scores.

RESULTS

706 with type 1 diabetes (mean age 41.9 years) and 604 controls (mean age 41.9 years) were enrolled. Gastrointestinal symptoms were significantly more frequent in type 1 diabetes compared with controls, in particular constipation (OR 2.4), diarrhea (OR 2.5), alternating bowel habit (OR 2.1), abdominal pain (OR 1.4), floating stools (OR 2.7), bloating (OR 1.4) and flatulence (OR 1.3) (all p<0.05). Previous pancreatitis was more frequent in type 1 diabetes (OR 4.6), but other gastrointestinal conditions were not. Gastrointestinal symptoms were associated with poorer glycemic control (p<0.01) and worse quality of life particularly in those with diarrhea. Investigation of those with diarrhea, including those with alternating bowel habit, (n=105), identified a cause in 72.3% with subsequent change in management.

CONCLUSIONS

Gastrointestinal symptoms are twice as common in type 1 diabetes and associated with poorer quality of life and glycemic control. Investigation of diarrhea in people with type 1 diabetes leads to a high yield of treatable conditions and a change in management in about three-quarters.

Identifying Patterns of Lifestyle Behaviors among People with Type 2 Diabetes in Tianjin, China: A Latent Class Analysis

INTRODUCTION

Lifestyle behaviors are essential elements of diabetes care. The aims of this study were to identify distinct subgroups of people with type 2 diabetes based on personal levels of lifestyle behaviors and explore the different characteristics across these subgroups.

METHODS

In 2015 and 2016, 1504 outpatients with a diagnosis of type 2 diabetes were selected via two-stage simple random sampling from 10 municipal district hospitals in Tianjin. Participants accepted an invitation by experienced physicians to complete a questionnaire containing demographic and lifestyle content. Clinical data were collected by reviewing medical records. Latent class analysis was applied to identify patterns of lifestyle behaviors. Multinomial logistic regression was used to investigate the characteristics of the subgroups.

RESULTS

The final model yielded a four-class solution: the healthy behavioral group, unhealthy diet and less activity group, smoking and drinking group, and sedentary and extremely inactive group. Further analysis found that variables, including age, sex, general/central obesity, treatment modalities, glycemic control, diabetes duration, and diabetes-related complications and comorbidities, were disproportionately distributed across the four latent classes (P < 0.05). Participants in the unhealthy diet and less activity group were more likely to have a longer duration of diabetes, poor glycemic control and more diabetes-related diseases relative to the other three latent classes.

CONCLUSIONS

Identification and characterization of subgroups based on lifestyle behaviors in individuals with type 2 diabetes can help health care providers to shift to targeted intervention strategies.

The association between pulse wave velocity and peripheral neuropathy in patients with type 2 diabetes mellitus

AIMS

Diabetic peripheral neuropathy (DPN) is the most common diabetic complication, affecting up to half of the patients with type 2 diabetes mellitus (T2DM). Increased aortic stiffness, measured with the carotid-femoral pulse wave velocity (PWV), has been associated with incidence of cardiovascular disease independently of traditional risk factors. Previous data showed associations between risk factors for macroangiopathy and DPN in diabetes. However, the association between PWV and DPN is not well known. In this study we examined the association between PWV and presence as well as severity of DPN in subjects with T2DM.

MATERIAL AND METHODS

A total of 381 patients with T2DM were recruited. Participants were classified as having DPN and not having DPN. PWV was measured at the carotid-femoral segment with a non-invasive method using applanation tonometry. DPN was assessed by determination of the Neuropathy Symptom Score (NSS) and the Neuropathy Disability Score (NDS).

RESULTS

A hundred and seven participants (28.1%) had DPN. Patients with DPN were significantly more often male and older, had longer diabetes duration, higher height, larger waist circumference, higher systolic arterial blood pressure (SBP) and higher PWV (all P<0.05). Furthermore, participants with DPN were treated more often with statins and had lower low density lipoprotein cholesterol; in addition, they were treated more often with antiplatelets, b-blockers and insulin than those without DPN. Univariative logistic regression analysis demonstrated that presence of DPN was significantly associated with age, male gender, longer diabetes duration, height, waist circumference, SBP, PWV, dyslipidemia, HbA1c, retinopathy, nephropathy and peripheral arterial disease. Multivariate logistic regression analysis, after adjustment for age, gender, waist circumference, SBP, nephropathy and use of b-blockers, demonstrated that the odds [OR (95% confidence intervals)] of peripheral neuropathy were associated significantly and independently only with diabetes duration [1.044 (1.009-1.081), P=0.013], height [1.075 (1.041-1.110), P<0.001], HbA1c [1.468 (1.164-1.851), P<0.001], PWV [1.174 (1.054-1.309), P=0.004], dyslipidemia [1.941 (1.015-3.713), P=0.045], retinopathy [4.426 (2.217-8.837), P<0.001] and peripheral arterial disease [4.658 (2.264-9.584), P<0.001]. In addition, multivariate linear regression analysis, after controlling for age, gender, diabetes duration, SBP, HbA1c and nephropathy, demonstrated that an increased NDS was significantly and independently associated with height [standardized regression coefficient (beta=0.229, P<0.001)], PWV (beta=0.197, P<0.001), retinopathy (beta=0.268, P<0.001) and peripheral arterial disease (beta=0.374, P<0.001).

CONCLUSION

Increased PWV is associated strongly and independently not only with the presence but also with the severity of DPN in patients with T2DM, irrespective of known risk factors.

Using Random Forest Models to Identify Correlates of a Diabetic Peripheral Neuropathy Diagnosis from Electronic Health Record Data

Objective

To identify variables correlated with a diagnosis of diabetic peripheral neuropathy (DPN) using random forest modeling applied to electronic health records.

Design

Retrospective analysis.

Setting

Humedica de-identified electronic health records database.

Subjects

Subjects ≥ 18 years old with type 2 diabetes from January 1, 2008-September 30, 2013 having continuous data for 1 year pre- and postindex with DPN (n = 35,050) and without DPN (n = 288,328) were identified.

Methods

Demographic, clinical, and health care resource utilization variables (e.g., inpatient and outpatient encounters, medications, and procedures) were input into a random forest model to identify the most important correlates of a DPN diagnosis. Random forest modeling is a computationally extensive, robust data mining technique that accommodates large sets of variables to identify associated factors using an ensemble of classifications trees. Accuracy of the model was evaluated using receiver operating characteristic curves (ROC).

Results

The final random forest model consisted of the following variables (importance) associated with a DPN diagnosis: Charlson Comorbidity Index score (100%), age (37.1%), number of pre-index procedures and services (29.7%), number of pre-index outpatient prescriptions (24.2%), number of pre-index outpatient visits (18.3%), number of pre-index laboratory visits (16.9%), number of pre-index outpatient office visits (12.1%), number of inpatient prescriptions (5.9%), and number of pain-related medication prescriptions (4.4%). ROC analysis confirmed model performance, with an area under the curve of 0.824 and accuracy of 89.6% (95% confidence interval 89.4%, 89.8%).

Conclusions

Random forest modeling can determine likelihood of a DPN diagnosis. Further validation of the random forest model may help facilitate earlier diagnosis and enhance management strategies.

Yang-warming method in the treatment of diabetic peripheral neuropathy: an updated systematic review and meta-analysis

BACKGROUND

Various studies have suggested the effectiveness of Chinese medicine in the treatment of diabetic peripheral neuropathy (DPN). There are several principles and methods in Chinese medicine for the treatment of DPN and yang-warming method is one of them. The purpose of this meta-analysis was to review the effectiveness and safety of yang-warming method using yang-warming Chinese medicine (YCM) in the treatment of DPN.

METHODS

A computer-based search of the articles from January 2001 to April 2016 with Chinese and English databases such as CNKI, CBM, Wanfang, VIP, Medline, Embase and Cochrane central register of controlled trials as well as manual search of the related articles was conducted. Randomized Controlled Trials (RCTs) comparing yang-warming Chinese medicines with western medicines in the treatment of DPN were considered for the study. The outcome measures were change in the sensory or motor nerve conduction velocity, total efficacy rate evaluated by clinical symptoms improvement, and adverse events. Two authors independently assessed the methodological quality of the included articles using Jadad scale and the twelve criteria recommended by Cochrane Back Review Group. Data were analyzed using RevMan 5.3 software provided by Cochrane collaboration.

RESULTS

A total of 25 articles were taken for the study. Meta-analysis results showed that yang-warming Chinese medicines used in the formula alone or in combination with western medicines improved the nerve conduction velocity (NCV) in comparison to western medicines alone (p < 0.001). There was also a significant difference in the total efficacy rate between the two groups (p < 0.001). Most of the included studies did not clearly report the adverse events.

CONCLUSIONS

Yang-warming Chinese medicines alone or in combination with western medicines were apparently better than conventional western medicines in the treatment of DPN. Because of the poor quality of the reported works that were available for the present meta-analysis, it is earlier to claim the superiority of yang-warming method using YCM to western medicines for the treatment of DPN. To support these early findings, further standardized and rigorous RCTs are required.

Diabetic foot syndrome in elderly patients

In elderly patients with diabetes mellitus and mild deterioration of the lower extremities, peripheral artery disease and diabetic peripheral neuropathy may contribute to the development of a diabetic foot syndrome. Early diagnosis and intervention can help to preserve the foot and thus significantly increase quality of life with diagnostic and therapeutic procedures being the same in elderly and in young patients.

Non-invasive diagnosis is possible in most bed-ridden patients and should take into account reasonable therapeutic options against the background of overall morbidity, physical performance and quality of life, which should be discussed with the patient and his relatives. Multidisciplinary care structures facilitate treatment and might lead to reduced amputation rates and an improved well-being.

Perceptions of Painful Diabetic Peripheral Neuropathy in South-East Asia: Results from Patient and Physician Surveys

There are no data on physician-patient communication in painful diabetic peripheral neuropathy (pDPN) in the Asia-Pacific region. The objective of this study was to examine patient and physician perceptions of pDPN and clinical practice behaviors in five countries in South-East Asia. Primary care physicians and practitioners, endocrinologists, diabetologists, and patients with pDPN completed separate surveys on pDPN diagnosis, impact, management, and physician-patient interactions in Hong Kong, Malaysia, the Philippines, Taiwan, and Thailand. Data were obtained from 100 physicians and 100 patients in each country. The majority of physicians (range across countries, 30-85%) were primary care physicians and practitioners. Patients were mostly aged 18-55 years and had been diagnosed with diabetes for >5 years. Physicians believed pDPN had a greater impact on quality of life than did patients (ranges 83-92% and 39-72%, respectively), but patients believed pDPN had a greater impact on items such as sleep, anxiety, depression, and work than physicians. Physicians considered the diagnosis and treatment of pDPN a low priority, which may be reflected in the generally low incidence of screening (range 12-65%) and a lack of awareness of pDPN. Barriers to treatment included patients' lack of awareness of pDPN. Both physicians and patients agreed that pain scales and local language descriptions were the most useful tools in helping to describe patients' pain. Most patients were monitored upon diagnosis of pDPN (range 55-97%), but patients reported a shorter duration of monitoring compared with physicians. Both physicians and patients agreed that it was patients who initiated conversations on pDPN. Physicians most commonly referred to guidelines from the American Diabetes Association or local guidelines for the management of pDPN. This study highlights important differences between physician and patient perceptions of pDPN, which may impact on its diagnosis and treatment. For a chronic and debilitating complication like pDPN, the physician-patient dialogue is central to maximizing patient outcomes. Strategies, including education of both groups, need to be developed to improve communication.

FUNDING

Pfizer.

Association between diabetic foot ulcer and diabetic retinopathy

PURPOSE

We aimed to investigate the prevalence of diabetic retinopathy (DR) in patients with diabetic foot ulcer (DFU) and elucidate the association between DR and DFU severities and their shared risk factors.

METHODS

A retrospective review was conducted on DFU patients who underwent ophthalmic and vascular examinations within 6 months; 100 type 2 diabetic patients with DFU were included. The medical records of 2496 type 2 diabetic patients without DFU served as control data. DR prevalence and severity were assessed in DFU patients. DFU patients were compared with the control group regarding each clinical variable. Additionally, DFU patients were divided into two groups according to DR severity and compared.

RESULTS

Out of 100 DFU patients, 90 patients (90%) had DR and 55 (55%) had proliferative DR (PDR). There was no significant association between DR and DFU severities (R = 0.034, p = 0.734). A multivariable analysis comparing type 2 diabetic patients with and without DFUs showed that the presence of DR [OR, 226.12; 95% confidence interval (CI), 58.07-880.49; p < 0.001] and proliferative DR [OR, 306.27; 95% CI, 64.35-1457.80; p < 0.001), higher HbA1c (%, OR, 1.97, 95% CI, 1.46-2.67; p < 0.001), higher serum creatinine (mg/dL, OR, 1.62, 95% CI, 1.06-2.50; p = 0.027), older age (years, OR, 1.12; 95% CI, 1.06-1.17; p < 0.001), higher pulse pressure (mmHg, OR, 1.03; 95% CI, 1.00-1.06; p = 0.025), lower cholesterol (mg/dL, OR, 0.94; 95% CI, 0.92-0.97; p < 0.001), lower BMI (kg/m2, OR, 0.87, 95% CI, 0.75-1.00; p = 0.044) and lower hematocrit (%, OR, 0.80, 95% CI, 0.74-0.87; p < 0.001) were associated with DFUs. In a subgroup analysis of DFU patients, the PDR group had a longer duration of diabetes mellitus, higher serum BUN, and higher serum creatinine than the non-PDR group. In the multivariable analysis, only higher serum creatinine was associated with PDR in DFU patients (OR, 1.37; 95% CI, 1.05-1.78; p = 0.021).

CONCLUSIONS

Diabetic retinopathy is prevalent in patients with DFU and about half of DFU patients had PDR. No significant association was found in terms of the severity of these two diabetic complications. To prevent blindness, patients with DFU, and especially those with high serum creatinine, should undergo retinal examinations for timely PDR diagnosis and management.

Risk Factors Associated With Corneal Nerve Alteration in Type 1 Diabetes in the Absence of Neuropathy: A Longitudinal In Vivo Corneal Confocal Microscopy Study

PURPOSE

The aim of this study was to determine alterations to the corneal subbasal nerve plexus (SNP) over 4 years using in vivo corneal confocal microscopy in participants with type 1 diabetes and to identify significant risk factors associated with these alterations.

METHODS

A cohort of 108 individuals with type 1 diabetes and no evidence of peripheral neuropathy at enrollment underwent laser-scanning in vivo corneal confocal microscopy, ocular screening, and health and metabolic assessment at baseline, and the examinations continued for 4 subsequent annual visits. At each annual visit, 8 central corneal images of the SNP were selected and analyzed to quantify corneal nerve fiber density, corneal nerve branch density and corneal nerve fiber length. Linear mixed model approaches were fitted to examine the relationship between risk factors and corneal nerve parameters.

RESULTS

A total of 96 participants completed the final visit and 91 participants completed all visits. No significant relationships were found between corneal nerve parameters and time, sex, duration of diabetes, smoking, alcohol consumption, blood pressure, or body mass index. However, corneal nerve fiber density was negatively associated with glycated hemoglobin (β = -0.76, P < 0.01) and age (β = -0.13, P < 0.01) and positively related to high-density lipids (β = 2.01, P = 0.03). Higher glycated hemoglobin (β = -1.58, P = 0.04) and age (β = -0.23, P < 0.01) also negatively impacted corneal nerve branch density. Corneal nerve fiber length was only affected by higher age (β = -0.06, P < 0.01).

CONCLUSIONS

Glycemic control, high-density lipid, and age have significant effects on SNP structure. These findings highlight the importance of diabetic management to prevent corneal nerve damage and the capability of in vivo corneal confocal microscopy for monitoring subclinical alterations in the corneal SNP in diabetes.

Footboards: Indigenous and Novel Method of Screening for Diabetes Peripheral Neuropathy - A Pilot Study

BACKGROUND

To validate the effectiveness of indigenously designed "footboard (FB)" in early diagnosis of diabetic peripheral neuropathy (PNP) by comparing it with Semmes-Weinstein monofilament (SWM) and vibration perception (VP).

MATERIALS AND METHODS

Two hundred and forty-four patients with diabetes were examined for PNP using SWM and 128 Hz tuning fork. The findings were compared with indigenously designed FBs with 1, 2, and 3 mm elevations.

RESULTS

Out of 108 patients who did not have protective sensation as per SWM, only 10 (9.2%) felt 1 mm board bearings, and out of 72 patients who did not feel vibration, only 8 (11.1%) felt 1 mm board bearings. Out of 136 patients who had protective sensation, 128 (94.11%) felt 2 mm elevated board bearings, and out of 172 patients who had VP, only 152 patients (88.3%) felt 2 mm board bearings. With SWM as standard, the sensitivities and specificities, respectively, were 63% and 90% (1 mm board), and 94% and 60% (2 mm board). With VP, the sensitivities and specificities, respectively, were 59% and 90% (1 mm board), and 88% and 61% (2 mm board).

CONCLUSIONS

FB, which simultaneously tests touch and pressure sensation, shows a high level of performance in detecting at-risk feet. FB may be simple, time-efficient, and inexpensive test for detection of neuropathy and needs further validation in a larger study.

Surgical Equinus Correction for the Diabetic Charcot Foot: What the Evidence Reveals

Triceps surae contracture, or equinus, is a known deforming force in the foot and ankle. Biomechanical studies have shown that ankle equinus significantly alters gait and plantar pressures, and in the diabetic neuropathic patient population, this can propagate plantar ulceration and/or Charcot neuroarthropathy (CN). Surgical correction of equinus is globally and frequently used to aid in plantar wound healing in the neuropathic diabetic patient, with and without CN. Treatment guidelines for equinus correction in this medically complex population are undefined and lack evidence from high-quality published peer-reviewed studies.

[Clinical features and diagnosis of diabetic polyneuropathy]

Diabetic polyneuropathy (DPN) is a serious complication of diabetes that leads to early disability in patients if late diagnosed. There has been a lot of research into pathophysiological mechanisms of nerve fiber damage and risk factors for neurological complications of diabetes. Early diagnosis of the latter is quite a challenge and, thus, the problem of finding more reliable diagnostic modalities is rather pressing. In this review, an interdisciplinary approach to the said problem, high-end diagnostic methods, and clinical features of DPN are described.

Integrated Tobacco Cessation Counseling in a Diabetes Self-management Training Program

Purpose

The purpose of this study was to evaluate the impact of a tobacco cessation intervention using motivational interviewing on smoking cessation rates during diabetes self-management training (DSMT).

Methods

A randomized controlled trial was conducted with subjects recruited from an ongoing type 2 diabetes adult education program at a large diabetes center. A total of 114 subjects were randomized to intervention (n = 57; face-to-face motivational interviewing plus telephone counseling and offering of medication) or standard care (n = 57). Outcome measures included tobacco cessation rates, mean number of cigarettes smoked, A1C, weight, blood pressure, and lipids.

Results

Intensive intervention using motivational interviewing integrated into a standard DSMT program resulted in a trend toward greater abstinence at 3 months of follow-up in those receiving the intervention. However, this same trend was not observed at 6 months. The addition of this structured smoking cessation intervention did not negatively affect either diabetes education or other measures of diabetes management, including A1C values.

A 10-yr follow-up study for the detection of peripheral neuropathy in young patients with type 1 diabetes

OBJECTIVE

The main objective of this work was to follow-up the development of diabetic neuropathy (DN) and its severity in patients with type 1 diabetes over 10 yr. Our intention was also to observe risk factor changes and verify which of them influence the development of neuropathy. The other objective was longitudinal study of electrophysiological parameters, focusing on the early diagnosis of DN.

METHODS

The prospective study comprised of 62 young patients with type 1 diabetes mellitus (DM) aged 13.9 ± 5.89 yr, with diabetes duration of 5.56 ± 5.11 yr, treated with an intensified insulin regimen. All patients underwent a detailed clinical neurological examination, nerve conduction study (NCS) and biothesiometry three times (baseline, after 5 yr, after 10 yr).

RESULTS

During the follow-up there was an increase in DN prevalence from 24.2% to 62.9% (p < 0.001). The proportion of patients with subclinical neuropathy increased from 17.7% to 46.8% (p < 0.001) and patients with clinical neuropathy from 6.5% to 16.1% (p < 0.001). The main contribution factors for rapid growth of the DN prevalence were poor glycaemic control, diabetes duration and patient's age. Regarding the conduction parameters, the most significant changes were observed in sural nerve SNAP amplitude (-5.2 m/s, p < 0.001) and sural nerve conduction velocity (-8.2 uV, p < 0.001). In contrast, the least significant changes were in peroneal nerve CMAP amplitude (-0.65 mV, p = 0.008).

CONCLUSIONS

The results of the study demonstrated a progressive increase in the DN prevalence over time, in particular its subclinical stages. The long-term poor glycaemic control was a determining factor in the rapid DN development. The sensory conduction parameters deteriorated faster than the motor parameters. The present study is one of few of those in type 1 DM, which in relation to risk factors assess not only the presence of neuropathy, but also its severity. The results support the necessity of a regular diagnostic search for DN in diabetic children.

Glycated albumin indicates peripheral diabetic neuropathy

AIMS

We investigated associations between serum levels of glycated albumin (GA) and glycated hemoglobin (HbA1c) and the presence of diabetic peripheral neuropathy (DPN) in patients with type 1 diabetes mellitus (T1DM).

METHODS

Between September 2009 and April 2015, we evaluated 314 patients with T1DM in the Endocrinology Department of Shengjing Hospital of China Medical University. We divided the patients into the DPN group (n = 72) and the non-DPN group (n = 242), on the basis of the presence of DPN.

RESULTS

The DPN group had significantly higher GA values than the non-DPN group. After univariate logistic regression, we selected several factors for further analysis: HbA1c, GA, duration of T1DM, body mass index, smoking, hypertension, and the presence of diabetic complications, including nephropathy, retinopathy, and cardiovascular disease. We performed a multivariate logistic regression analysis to examine the association between the presence of DPN and each of these variables. We identified GA, HbA1c, hypertension, smoking, retinopathy, and cardiovascular disease as independent variables for indicating the presence of DPN. Results of a receiver operating characteristic curve analysis revealed that the area under the curve of GA (0.771) was larger than that of HbA1c (0.629). We defined the cutoff value of GA as 23.5 % (sensitivity 0.764, specificity 0.661) and the cutoff value of HbA1c as 8.45 % (sensitivity 0.667, specificity 0.595) for predicting DPN in patients with T1DM.

CONCLUSIONS

GA may be a better indicative marker of DPN in patients with T1DM than HbA1c.

Diabetic peripheral neuropathy: Correlation between nerve cross-sectional area on ultrasound and clinical features

BACKGROUND AND OBJECTIVE

To evaluate the correlations of the cross-sectional area (CSA) of peripheral nerves in diabetic peripheral neuropathy (DPN) patients based on ultrasound (US) with clinical and demographic characteristics.

METHODS

A DPN patient group (n= 53) and a matched healthy control group (n= 53) underwent US imaging of the sciatic, tibial and median nerves. The CSAs of these nerves were recorded, and their associations with pain intensity according to the visual analog scale (VAS) score and the Leeds Assessment of Neuropathic Symptoms and Signs (LANSS) pain scale score, diabetes mellitus (DM) duration, body mass index (BMI), HbA1c level and blood glucose levels were evaluated.

RESULTS

The CSAs of the examined nerves in diabetic patients were larger than those in healthy individuals (p< 0.05). No correlations were detected between the CSAs of the examined nerves and the parameters of interest (p> 0.05), including the VAS and LANSS pain scale scores (p= 0.32 and p= 0.31, respectively).

CONCLUSIONS

US is a sensitive diagnostic technique for detecting DPN; however, it does not indicate disease severity.

Targeting glucose metabolism for healthy aging

Advancing age is the greatest single risk factor for numerous chronic diseases. Thus, the ability to target the aging process can facilitate improved healthspan and potentially lifespan. Lack of adequate glucoregulatory control remains a recurrent theme accompanying aging and chronic disease, while numerous longevity interventions result in maintenance of glucoregulatory control. In this review, we propose targeting glucose metabolism to enhance regulatory control as a means to ameliorate the aging process. We highlight that calorie restriction improves glucoregulatory control and extends both lifespan and healthspan in model organisms, but we also indicate more practical interventions (i.e., calorie restriction mimetics) are desirable for clinical application in humans. Of the calorie restriction mimetics being investigated, we focus on the type 2 diabetes drug acarbose, an α-glucosidase inhibitor that when taken with a meal, results in reduced enzymatic degradation and absorption of glucose from complex carbohydrates. We discuss alternatives to acarbose that yield similar physiologic effects and describe dietary sources (e.g., sweet potatoes, legumes, and berries) of bioactive compounds with α-glucosidase inhibitory activity. We indicate future research should include exploration of how non-caloric compounds like α-glucosidase inhibitors modify macronutrient metabolism prior to disease onset, which may guide nutritional/lifestyle interventions to support health and reduce age-related disease risk.

Diabetic peripheral neuropathy may not be as its name suggests: evidence from magnetic resonance imaging

Diabetic peripheral neuropathy (DPN) affects up to 50% of patients with diabetes and is a major cause of morbidity and increased mortality. Its clinical manifestations include distressing painful neuropathic symptoms and insensitivity to trauma that result in foot ulcerations and amputations. Several recent studies have implicated poor glycemic control, duration of diabetes, hyperlipidemia (particularly hypertryglyceridaemia), elevated albumin excretion rates, and obesity as risk factors for the development of DPN. However, similar data are not available for painful DPN. Moreover, although there is now strong evidence for the importance of peripheral nerve microvascular disease in the pathogenesis of DPN, peripheral structural biomarkers of painful DPN are lacking. However, there is now emerging evidence for the involvement of the central nervous system in both painful and painless DPN afforded by magnetic resonance imaging. This review will focus on this emerging evidence for central changes in DPN, hitherto considered a peripheral nerve disease only.

Entrapment neuropathies in diabetes mellitus

Neuropathy is a common complication of diabetes mellitus (DM) with a wide clinical spectrum that encompasses generalized to focal and multifocal forms. Entrapment neuropathies (EN), which are focal forms, are so frequent at any stage of the diabetic disease, that they may be considered a neurophysiological hallmark of peripheral nerve involvement in DM. Indeed, EN may be the earliest neurophysiological abnormalities in DM, particularly in the upper limbs, even in the absence of a generalized polyneuropathy, or it may be superimposed on a generalized diabetic neuropathy. This remarkable frequency of EN in diabetes is underlain by a peculiar pathophysiological background. Due to the metabolic alterations consequent to abnormal glucose metabolism, the peripheral nerves show both functional impairment and structural changes, even in the preclinical stage, making them more prone to entrapment in anatomically constrained channels. This review discusses the most common and relevant EN encountered in diabetic patient in their epidemiological, pathophysiological and diagnostic features.

Cardiovascular Autonomic Neuropathy, Sexual Dysfunction, and Urinary Incontinence in Women With Type 1 Diabetes

OBJECTIVE

This study evaluated associations among cardiovascular autonomic neuropathy (CAN), female sexual dysfunction (FSD), and urinary incontinence (UI) in women with type I diabetes mellitus (T1DM).

RESEARCH DESIGN AND METHODS

We studied 580 women with T1DM in the Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications Study (DCCT/EDIC). CAN was defined as: 1) R-R variation <15 with deep breathing or 2) R-R variation of 15-19.9 plus Valsalva ratio ≤1.5 or a supine-to-standing drop of 10 mmHg in diastolic blood pressure. A Sandvik Severity Index of 3-12 defined UI, and a Female Sexual Function Index (FSFI-R) score ≥22.75 defined FSD. Multivariable models estimated associations among CAN, FSD, and UI.

RESULTS

At EDIC year 17, FSD was observed in 41% of women and UI in 30%. No statistically significant associations were observed between measures of CAN at DCCT closeout and subsequent report of FSD or UI. At EDIC year 16/17, there was a 53% increased odds of having UI with a Valsalva ratio ≤1.5. At both EDIC year 13/14 and EDIC year 16/17, a 5-unit increase in R-R variation was associated with a 1.11 greater odds of having FSD.

CONCLUSIONS

In women with T1DM in the DCCT/EDIC, we found significant increased odds of FSD and UI with specific measures of CAN. In long-standing T1DM, CAN may predict development of FSD and may be a useful surrogate for generalized diabetic autonomic neuropathy.

Painful diabetic neuropathy — current understanding and management for the primary care team

Primary care has an increasing role in the diagnosis and treatment of painful diabetic neuropathy (PDN), and early accurate diagnosis and intervention can greatly improve the prognosis. With the incidence of diabetes predicted to increase dramatically, the number of patients with PDN is set to soar. PDN can have a serious impact on quality of life, leading to severe depression and even suicide. The evolution of a schematic approach to the diagnosis and treatment of PDN can offer new hope to many patients. This review focuses on PDN and current treatment strategies. Many leading pain clinics have adopted a multidisciplinary approach to the pharmacological and non-pharmacological management of PDN.

Diabetic neuropathy: achieving best practice

Peripheral neuropathy is one of the commonest complications of diabetes and the commonest form of neuropathy in the developed world.1 Diabetic polyneuropathy encompasses several neuropathic syndromes, and the commonest presentation is chronic distal symmetrical neuropathy (DSP). DSP, often associated with autonomic neuropathy, has two clinical consequences: namely neuropathic pain and foot ulceration. Both often occur in the same individual, and cause severe curtailment of quality of life. The other, less common presentations of diabetic polyneuropathy include acute painful neuropathies, and focal neuropathies (amyotrophy, pressure palsies, truncal radiculopathies, mononeuropathies and mononeuritis multiplex).2 Table 1 shows a recent classification of diabetic polyneuropathy based upon the natural history of the various syndromes.3

Insights into the pathogenesis and treatment of painful diabetic neuropathy

Painful diabetic distal symmetrical polyneuropathy (painful DPN) is a puzzle with two important missing pieces: Firstly we still do not understand why only some patients with neuropathy experience painful symptoms; Secondly we still do not have a complete understanding of how nociception generated in the peripheral nervous system is processed by the central nervous system (CNS). Available treatments offer only symptom relief and there is currently no effective treatment based on arresting or reversing the progression of disease. Therefore the management of painful DPN remains less than optimal because the complex pathophysiology of nociception and pain perception in health and disease is incompletely understood. Studies of the peripheral nervous system are investigating the molecular processes involved in signal transduction that have the potential to be interrupted or modified to ease pain. Magnetic resonance imaging techniques are helping to elucidate central pain processing pathways and describe the translation of nociception to pain. Combining the knowledge from these two streams of enquiry we will soon be able to predict accurately who will develop painful DPN, how we can halt or reverse the condition, or who will respond to symptomatic treatments. Future developments in the treatment of painful DPN will be underpinned by decoding the peripheral and central mechanisms of pain. Research is focusing on these areas of enquiry in the hope that answers will lead to effective treatments to alleviate pain and reverse pathology for those suffering from painful DPN.

Updates in diabetic peripheral neuropathy

Diabetes has become one of the largest global health-care problems of the 21 ^st century. According to the Centers for Disease Control and Prevention, the population prevalence of diabetes in the US is approaching 10% and is increasing by 5% each year. Diabetic neuropathy is the most common complication associated with diabetes mellitus. Diabetes causes a broad spectrum of neuropathic complications, including acute and chronic forms affecting each level of the peripheral nerve, from the root to the distal axon. This review will focus on the most common form, distal symmetric diabetic polyneuropathy. There has been an evolution in our understanding of the pathophysiology and the management of diabetic polyneuropathy over the past decade. We highlight these new perspectives and provide updates from the past decade of research.

Cardiovascular Autonomic Dysfunction Predicts Diabetic Foot Ulcers in Patients With Type 2 Diabetes Without Diabetic Polyneuropathy

We investigated the factors that might influence the development of diabetic foot ulcers (DFUs) in type 2 diabetes patients without diabetic polyneuropathy (DPN).From January 2000 to December 2005, a total of 595 patients who had type 2 diabetes without DPN between the ages of 25 and 75 years, and had no prior history of DFUs were consecutively enrolled in the study. A cardiovascular autonomic function test was performed to diagnose cardiovascular autonomic neuropathy (CAN) using heart rate variability parameters.The median follow-up time was 13.3 years. Among the 449 (75.4%) patients who completed the follow-up evaluation, 22 (4.9%) patients developed new ulcers, and 6 (1.3%) patients underwent the procedure for lower extremity amputations. The patients in the DFUs group had a longer duration of diabetes, higher baseline HbA1c levels, higher rates of nephropathy, and CAN. A Cox hazard regression analysis results revealed that the development of DFUs was significantly associated with the presence of CAN (normal vs definite CAN; HR, 4.45; 95% confidence interval, 1.29-15.33) after adjusting for possible confounding factors.The development of DFUs was independently associated with CAN in patients with type 2 diabetes without DPN. We suggested the importance of CAN as a predictor of DFUs even in the patients without DPN, and the need to pay attention to patients with definite CAN and type 2 diabetes.