Prevalence of distal diabetic polyneuropathy using quantitative sensory methods in a population with diabetes of more than 10 years' disease duration

Prevalence of carpal tunnel syndrome in patients with long-term type 2 diabetes mellitus

Generally, Carpal tunnel syndrome (CTS) is more common in diabetes mellitus (DM), especially in subjects with coexisting diabetic polyneuropathy (DPN) and/or long-term DM. Based on the analysis of nerve conduction velocity (NCV), the prevalence of CTS and the features of nerve injury were retrospectively explored in type 2 diabetes mellitus (T2DM) patients. In this cohort, there were 353 T2DM patients who were hospitalized in Taiyuan Central Hospitalbetween January 2018 and January 2019. The pathological rates of NCVs between the left and right median nerves were compared, including the gender effect. The examinations were mainly directed to analyze the median nerve injury features. Among 353 patients, 139 patients (39.3%) presented with CTS. These 139 T2DM patients with CTS were then divided into groups based on the nerve injury location and injured nerve type. The prevalence of sensory nerve injury (SNI) was higher than that of motor nerve injury (MNI). The CTS patients had a significantly higher occurrence rate of SNI than MNI (P < 0.05). The abnormal rate of sensory nerve conduction velocity (SCV, P = 0.01) and motor nerve conduction velocity (MCV, P < 0.05) were higher in the right median nerve. No significant differences were detected for other nerves on either side. Significant differences in abnormal rates of SCV of the left (P = 0.04) and the right (P = 0.03) median nerves between the two genders were found. There were no significant abnormalities for other nerves on either side and either gender. Early screening of NCV is needed for T2DM patients to detect CTS with a high prevalence rate. This study suggests that early detection of NCV can identify CTS in the absence of clinical conditions and SNI may occur earlier in long-term T2DM patients with CTS.

Diabetic retinopathy as a predictor for peripheral compression neuropathies, a registry-based study

Diabetes is characterized by hyperglycaemia and entails many complications, including retinopathy and entrapment neuropathies, such as ulnar nerve entrapment (UNE) and carpal tunnel syndrome (CTS). Hyperglycaemia damages the nerves of the retina, as well as peripheral nerves. There is a correlation between entrapment neuropathies and retinopathy in patients with diabetes, but whether patients with diabetic retinopathy are more prone to develop CTS and UNE is uncertain. Hence, the aim was to investigate if retinopathy can be used as a factor predicting the development of CTS and UNE. Data from 95,437 individuals from the National Diabetes Registry were merged with data from the Skåne Healthcare Registry. The population was analysed regarding prevalence of CTS or UNE and retinopathy status. Population characteristics were analysed using the Chi2-test, Student's Independent T-test, and the Mann-Whitney U-test. Two logistic regression models were used to analyse the odds ratio (OR) for development of CTS and UNE depending on retinopathy status, adjusted for possible confounders. Both CTS and UNE were more frequent among those with retinopathy, compared to those without (CTS: 697/10,678 (6.5%) vs. 2756/83,151 (3.3%; p<0.001), (UNE: 131/10,678 (1.2%) vs. 579/83,151 (0.7%; p<0.001)). The OR for developing CTS for individuals with type 1 diabetes and retinopathy was 2.40 (95% CI 2.06-2.81; p<0.001) and of developing UNE was 1.53 (0.96-2.43; p = 0.08). The OR for developing CTS for individuals with type 2 diabetes and retinopathy was 0.93 (0.81-1.08; p = 0.34) and for UNE 1.02 (0.74-1.40; p = 0.90). Diabetic retinopathy is associated with a higher risk of developing CTS and UNE, but the association seems to be mediated by the duration of the diabetes. Higher HbA1c levels, longer diabetes duration and higher BMI are significant risk factors for developing CTS and UNE in type 1 and type 2 diabetes.

Clinical study of diabetic peripheral neuropathy screening by retinal vascular geometric parameters

To investigate the relationship between geometrical changes of retinal vessels and diabetic peripheral neuropathy (DPN), and to determine the effectiveness of retinal vascular geometry analysis and vibration perception threshold (VPT) for DPN assessment. Type 2 diabetes patients (n = 242) were categorized by stage of DPN. VPT and fundus photography was performed to obtain retinal vascular geometry parameters. The risk factors for DPN and the correlation between DPN stages were analyzed. The efficiency of the retinal vascular geometric parameters obtained with VPT as a diagnostic tool for DPN was examined. Stages of DPN showed a linear correlation with VPT (r = 0.818), central retinal vein equivalent (CRVE) (r = 0.716), and fractal dimension arterioles (DFa) (r = - 0.769). VPT, CRVE, DFa, and fractal dimension veins (DFv) showed high sensitivity (80%, 55%, 82%, and 67%, respectively) and specificity (92%, 93%, 82%, and 80%, respectively) for DPN diagnosis. Good agreement was observed between combined use of geometric parameters (CRVE, DFa and DFv) and VPT (Kappa value 0.430). The detection rate of DPN with combined use of geometric parameters of retinal vessels (64.88%) was significantly higher than that with use of VPT (47.52%). Retinal vascular geometry changes demonstrated significant correlation with DPN severity. VPT, CRVE, DFa, and DFv may provide insights for understanding DPN.

A Review on Cellular and Molecular Mechanisms Linked to the Development of Diabetes Complications

Modern lifestyle, changing eating habits and reduced physical work have been known to culminate into making diabetes a global pandemic. Hyperglycemia during the course of diabetes is an important causative factor for the development of both microvascular (retinopathy, nephropathy and neuropathy) and macrovascular (coronary artery disease, stroke and peripheral artery disease) complications. In this article, we summarize several mechanisms accountable for the development of both microvascular and macrovascular complications of diabetes. Several metabolic and cellular events are linked to the augmentation of oxidative stress like the activation of advanced glycation end products (AGE) pathway, polyol pathway, Protein Kinase C (PKC) pathway, Poly-ADP Ribose Polymerase (PARP) and hexosamine pathway. Oxidative stress also leads to the production of reactive oxygen species (ROS) like hydroxyl radical, superoxide anion and peroxides. Enhanced levels of ROS rescind the anti-oxidant defence mechanisms associated with superoxide dismutase, glutathione and ascorbic acid. Moreover, ROS triggers oxidative damages at the level of DNA, protein and lipids, which eventually cause cell necrosis or apoptosis. These physiological insults may be related to the microvascular complications of diabetes by negatively impacting the eyes, kidneys and the brain. While underlying pathomechanism of the macrovascular complications is quite complex, hyperglycemia associated atherosclerotic abnormalities like changes in the coagulation system, thrombin formation, fibrinolysis, platelet and endothelial function and vascular smooth muscle are well proven. Since hyperglycemia also modulates the vascular inflammation, cytokines, macrophage activation and gene expression of growth factors, elevated blood glucose level may play a central role in the development of macrovascular complications of diabetes. Taken collectively, chronic hyperglycemia and increased production of ROS are the miscreants for the development of microvascular and macrovascular complications of diabetes.

Prevalence of neuropathy in patients with type 2 diabetes in Iran : A systematic review and meta-analysis

BACKGROUND

Diabetic neuropathy is one of the most common complications of diabetes, which leads to amputation and significant disability in patients. Studies conducted in this field show different prevalences and inconsistencies in the country. This study attempts to determine the overall prevalence of neuropathy in patients with type 2 diabetes in Iran with a meta-analysis.

METHODS

The present study was conducted using a meta-analysis method from January 2000 to December 2018. The papers related to the study subject were obtained from searching Scopus, ScienceDirect, Magiran, Barakat Knowledge Network, SID, Medline (PubMed), and Google Scholar databases. The heterogeneity of studies was examined using I² index and the data were analyzed using the software Comprehensive Meta-Analysis (version 3, Biostat, Englewood, NJ, USA).

RESULTS

The results of the systematic review showed regional differences in the prevalence of neuropathy in Iran. According to the meta-analysis and review of 10 studies and 2992 individuals between the ages of 5 years and 86 years, the overall prevalence of neuropathy in type 2 diabetes patients in Iran was 56.5% (95% confidence interval, CI 42.8-69.3%). The highest prevalence of neuropathy in type 2 diabetic patients was found in Mashhad with 87.2% (95% CI 77.9-92.3%) in 2012 and the lowest prevalence of neuropathy in type 2 diabetic patients was found in Ahvaz with 22.7% (95% CI 18.5-27.6%) in 2014. With the increase in years of research, the prevalence of neuropathy in type 2 diabetes in Iran was reduced, with statistically significant differences (P < 0.05).

CONCLUSION

Considering the high prevalence of neuropathy in patients with type 2 diabetes in the country, it is essential that health policy makers take effective measures to reduce this disease in diabetes patients.

Prevalence and associated factors of painful diabetic peripheral neuropathy among diabetic patients on follow up at Jimma University Medical Center

BACKGROUND

Despite having significant impact on the patient's quality of life, painful diabetic peripheral neuropathy (PDPN) is usually underdiagnosed. Screening for PDPN in patients with diabetes is needed in order to get timely identification and management. Hence, the purpose of this study was to assess the prevalence and determinants of PDPN among diabetes patients attending outpatient at Jimma University Medical Center from September 1 November 10, 2019.

METHODS

Hospital based cross-sectional study was conducted and douleur neuropathique-4 was used to identify the presence of PDPN. Data were collected using pretested structured questionnaire and entered into EPI data 3.1 and exported to SPSS version 20 for analysis. Both bivariate and multivariate binary logistic regression was employed to identify factors associated with PDPN. Variable having a p value of <0.25 in the bivariate model were considered as candidates for multivariable regression. Adjusted odds ratios were calculated at 95%CI and considered significant with a p value of <0.05.

RESULTS

A total of 366 diabetic patients were enrolled into the study and their mean duration of diabetes was 6.8 ± 5.3 years. The study finding showed that the prevalence of PDPN was 14.5%. According to the multivariate logistic regression analysis smoking [current smoker(AOR = 6.17; 95%CI:2.25,16.86),former smoker(AOR = 3.22;95%CI:1.29,8.03)],diabetes duration[5 to 10 years (AOR = 3.32;95%CI:1.29,8.53), ≥ 10 years (AOR = 8.86;95% CI: 3.49,22.5)] and comorbid hypertension [AOR = 2.54; 95%CI:1.17,5.49] were independent predictors of PDPN among study participants.

CONCLUSION

The overall prevalence of PDPN in this study was 14.5% and it was significantly associated with smoking, comorbid hypertension and diabetes duration of above 5 years. Early detection and appropriate interventions are important for high risk patients identified in the current study.

The Slipping Slipper Sign: A Poor Man's Test for Severe Diabetic Peripheral Neuropathy

BACKGROUND

Neuropathic feet are at very high risk for infection and amputation. The slipping slipper sign (SSS) is elicited by a simple questionnaire test reported to detect the presence of severe diabetic peripheral neuropathy. This test can be administered by non-medical staff. In this study, subjects with and without the SSS were evaluated by nerve conduction studies (NCS) and ultrasound measurements of the right sural nerve diameters as well as with traditional scoring systems for peripheral and autonomic neuropathy.

OBJECTIVE

To demonstrate that the Slipping Slipper Sign can be used as an index of severe diabetic peripheral neuropathyMethod:This was a prospective cross sectional study in which 74 patients with diabetes (38 positive and 36 negative for SSS) underwent ultrasonography and NCS of the right sural nerve by an examiner blinded to SSS status. Findings were evaluated against demography, clinical history, anthropometry as well as traditional clinical and autonomic neuropathic scores.

RESULTS

Patients without the SSS [median (IQR) = 10.0 years (4.0-20.3)] had a significantly shorter duration of diabetes compared with those with the SSS [median (IQR) = 15.0 years (8.5-25.0)], p = 0.028. The frequencies of retinopathy (36.8% vs 2.8%, p <  0.05) and cerebrovascular accidents (18.4% vs 13.9 %, p <  0.05) were higher among those with SSS compared with those without. Differences in nerve conduction characteristics were markedly significant. The amplitude of the sural sensory nerve action potential (SNAP) was ([median (IQR)] 0 microvolts vs 4.0 microvolts (0.0-10.8) p <  0.002) between those with and without SSS, respectively whilst none of patients with SSS had a recordable SNAP vs 78% without a SSS. Similarly, maximal thickness of the right sural nerve at the ankle 3.0 mm (2.3-3.4) vs 3.5 mm (3.0-3.9), and leg 3.4 mm (2.7-3.8) vs 3.9 mm (3.3-4.2) was reduced, p <  0.01 in patients with the SSS compared with those with a negative SSS.

CONCLUSION

The SSS identifies feet with objective neurophysiological and imaging characteristics of severe neuropathy.

Association between alterations of corneal sub-basal nerve plexus analyzed with in vivo confocal microscopy and long-term glycemic variability

Purpose:

The effect of long-term glycemic variability upon corneal sub-basal nerve plexus (CSNP) morphology analyzed by in vivo confocal microscopy (IVCM) has been poorly investigated in the setting of type 1 diabetes mellitus (T1DM). Our purpose was to analyze the association between morphometric parameters of CSNP and new markers of glycemic variability in a population of patients with T1DM.

Methods:

Forty patients with T1DM underwent: assessment of diabetic neuropathy (DN); analysis of subcutaneous advanced glycated end-products; IVCM scans of CSNP. The fully automated software ACCMetrics was employed to analyze IVCM images and calculate seven corneal nerve parameters. Data of diabetes duration, mean and standard deviation (SD) of either last-year and all-time glycated hemoglobin (HbA1C) were retrieved.

Results:

Diabetes duration and all-time SD of HbA1C were independently associated with CNFD (R = –0.26, p = 0.01; R = –0.27, p = 0.047 respectively), CNFL (R = –0.12; p = 0.01; R = –0.17, p = 0.01 respectively) and CNFrD (R = –0.001, p = 0.009; R = –0.002, p = 0.007 respectively). The analysis of the association among IVCM parameters and specific subtypes of DN showed that altered cold sensitivity was independently associated with CNFD (B = –0.24, p = 0.01), CNFL (B = –0.46, p = 0.01) and CNFrD (B = –28.65, p = 0.03).

Conclusions:

All-time SD of HbA1C and disease duration were found to be independent predictors of damage to CSNP in patients with T1DM.

Diagnosis Accuracy of Carpal Tunnel Syndrome in Diabetic Neuropathy

Background and objectives: Carpal tunnel syndrome (CTS) is a common pathology, but sometimes the diagnosis is delayed in patients with diabetic neuropathy (DN). The aim of the study is twofold: first, to compare the accuracy of ultrasound (US) with that of electroneurography (ENG) in the diagnosis of CTS associated with DN, using the clinical diagnosis as a reference standard, and second, to investigate the correlation between morphological US parameters and electrodiagnosis (EDX) measurements in patients with CTS and DN. Materials and Methods: This study included patients with DN. They were divided into two groups: Control (patients without CTS) and Cases (patients with CTS). We performed US and ENG in both hands, totaling 56 wrists, with 28 wrists in each group. Results: We found that the difference in the sensory distal latencies between the median and the ulnar nerves (ring finger) exhibited the highest diagnostic accuracy of all the US and ENG parameters, areas under the receiver operating characteristic (AUC) = 0.99 (95% CI 0.97–1), and it was significantly different from the best US diagnostic method. The wrist cross-sectional area (CSA) had the most accurate US diagnosis, while the wrist-to-forearm ratio had the worst AUC. Moreover, in the group of CTS and DN patients, the wrist CSA enlargement was statistically directly proportional to the median compound muscle action potential (CMAP) distal latency and inversely proportional to the antidromic median nerve conduction study (NCS) and the orthodromic median palm–wrist NCS. Conclusions: Both examinations can be used with confidence in the diagnosis of CTS overlapping with DN, but the EDX examination seems to be more accurate. Furthermore, we found a positive correlation between the US and EDX parameters.

Augmented Corneal Nerve Fiber Branching in Painful Compared With Painless Diabetic Neuropathy

CONTEXT

The factors that determine the development of diabetic sensorimotor polyneuropathy (DSPN) as a painful or painless entity are unknown.

OBJECTIVE

We hypothesized that corneal nerve pathology could be more pronounced in painful DSPN, indicating predominant small nerve fiber damage.

DESIGN AND METHODS

In this cross-sectional study, we assessed 53 patients with painful DSPN, 63 with painless DSPN, and 46 glucose-tolerant volunteers by corneal confocal microscopy (CCM), nerve conduction (NC), and quantitative sensory testing. DSPN was diagnosed according to modified Toronto Consensus criteria. A cutoff at 4 points on the 11-point rating scale was used to differentiate between painful and painless DSPN.

RESULTS

After adjustment for age, sex, body mass index, and smoking, corneal nerve fiber density, corneal nerve fiber length, and corneal nerve branch density (CNBD) were reduced in both DSPN types compared with the control group (P < 0.05). Only CNBD differed between the groups; it was greater in patients with painful DSPN compared with those with painless DSPN [55.8 (SD, 29.9) vs 43.8 (SD, 28.3) branches/mm2; P < 0.05]. Several CCM measures were associated with NC and cold perception threshold in patients with painless DSPN (P < 0.05) but not those with painful DSPN.

CONCLUSION

Despite a similarly pronounced peripheral nerve dysfunction and corneal nerve fiber loss in patients with painful and painless DSPN, corneal nerve branching was enhanced in those with painful DSPN, pointing to some susceptibility of corneal nerve fibers toward regeneration in this entity, albeit possibly not to a sufficient degree.

Prevalence and Determinants of Painful and Painless Neuropathy in Type 1 Diabetes Mellitus

Aims: To evaluate (1) the prevalence of diabetic distal symmetrical sensory-motor polyneuropathy (DSPN) and painful DSPN among patients with type 1 diabetes mellitus (DM1) aged over 18 years and (2) the determinant factors of neuropathy and pain in those patients. Materials and Methods: An epidemiological, cross-sectional, observational study was performed; 330,386 people were included, and a total of 444 people were diagnosed with DM1. After exclusion of possible confounders, 360 patients were assessed for painless and painful DSPNs using neurological examination and questionnaires for neuropathy and pain. Odds ratio (OR) and confidence intervals (95% CI) were estimated using multinomial logistic regression models. The analysis was based on a framework with four conceptual levels that consider feasible pathways between several risk factors: (1) socio-demographic factors and diabetes duration, (2) patient habits, (3) co-morbidities, and (4) metabolic factors and disease complications. Results: The prevalence of DSPN and painful DSPN were 42.8 and 18.9%, respectively. Diabetes duration was positively associated with painful (OR = 1.107, 95% CI: 1.107-1.139) and painless DSPN (OR = 1.069, 95% CI: 1.043-1.096). Education level was negatively associated with painful DSPN (OR = 0.889, 95% CI: 0.826-0.957). Sex (female) was positively associated only with painless DSPN (OR = 1.769, 95% CI: 1.007-3.107). Being a current or former smoker was positively associated only with painless DSPN (OR = 1.940, 95% CI: 1.069-3.518). Hypertension was positively associated with painful DSPN (OR = 2.474, 95% CI: 1.110-5.512) and painless DSPN (OR = 2.565, 95% CI: 1.252-5.256). Glycated hemoglobin (HbA1c) was positively associated only with painless DSPN (OR = 1.193, 95% CI: 1.018-1.399). Conclusions: Diabetes duration and hypertension have a direct impact on the development of painful and painless DSPN. However, female sex and HbA1c have a direct effect only on the development of painless DSPN, and education level has an indirect effect on the development of painful DSPN. Therefore, it can be concluded that different etiological factors have different contributions to the development of neuropathy and pain.

Association Between Overactive Bladder and Polyneuropathy in Diabetic Patients

Purpose

Diabetes mellitus (DM) is a chronic metabolic disorder that often leads to complications. We aimed to correlate two complications of DM, polyneuropathy and hyperactive bladder syndrome, using noninvasive measures, such as screening tests.

Methods

We included 80 female and 40 male type 2 diabetic patients in this prospective study. Diabetic polyneuropathy evaluations were conducted using the Douleur Neuropathique 4 Questions (DN4), and overactive bladder (OAB) evaluations were performed using the Overactive Bladder Questionnaire (OAB-V8). The patients were also evaluated for retinopathy and nephropathy. The diabetic male and female patients with or without OAB were chosen and compared for microvascular complications (polyneuropathy, retinopathy, and nephropathy).

Results

There were no significant correlations between OAB and retinopathy as well as between OAB and nephropathy among diabetic patients (female patients, P>0.05; male patients, P>0.05). However, the patients with OAB were significantly more likely to develop polyneuropathy (female patients, P<0.05; male patients, P<0.05).

Conclusions

In diabetic patients, OAB and diabetic peripheral neuropathy are significantly correlated. These correlations were demonstrated using short, understandable, valid, and reliable disease-specific tests without invasive measures. Using these screening tests, both neurologists and urologists can easily diagnose these complications.

Validation and Reliability of the Portuguese Version of the Michigan Neuropathy Screening Instrument

BACKGROUND

Diabetic peripheral neuropathy is very common in the diabetic population. Early screening for foot pathology is of the utmost importance. The Michigan Neuropathy Screening Instrument (MNSI) is an easy, brief, and noninvasive screening tool. The aim of this study was to validate the semantics and characteristics of both sections of the Portuguese translation of the MNSI for Portuguese diabetic patients.

METHODS

A cross-sectional study was performed on 87 type 1 and 2 diabetic patients at our outpatient endocrinology department. The final sample was composed of 76 patients. Nerve conduction studies were requested, but only a subsample of 42 patients agreed to participate in them.

RESULTS

The scale was internally consistent (Cronbach's alpha > 0.70 in section A, or a clinical history questionnaire and a physical examination [section B]), and the scores of both sections were positively correlated (r = 0.70; P < 0.001). With regard to stability, MNSI scores between test/retest showed high stability (intraclass correlation coefficient = 0.91). The receiver-operating characteristic (ROC) demonstrated its validity, with ROC curve values for section A, section B, and sections A + B of 0.913, 0.798, and 0.906 respectively. Considering a cut off of ≥ 3 in section A and of ≥ 2 in section B, we obtained a sensitivity of 100% and 86%; a specificity of 64% and 61%; a positive predictive value of 80% and 73%; and a negative predictive value of 100% and 79%, respectively.

CONCLUSIONS

The Portuguese MNSI is a reliable and valid tool for screening diabetic neuropathy.

The Diagnostic Value of Neuropathy Symptom and Change Score, Neuropathy Impairment Score and Michigan Neuropathy Screening Instrument for Diabetic Peripheral Neuropathy

AIMS

This study aims to evaluate the diagnostic capabilities of neuropathy symptom and change (NSC) score, neuropathy impairment score (NIS) and Michigan neuropathy screening instrument (MNSI) in diagnosing diabetic peripheral neuropathy (DPN).

METHODS

A total of 131 patients with type II diabetes received NSC, NIS and MNSI scoring systems. Electromyography/nerve conduction velocity (EMG/NCV) test was taken as gold standard. Correlations between EMG/NCV test and the 3 scorings, and their sensitivity, specificity, positive and negative predictive values, accuracy and kappa (x03BA;) value were analyzed.

RESULTS

The prevalence of DPN was 43.5% according to EMG/NCV findings. EMG/NCV test was significantly positive correlated with all the 3 scorings, highest with NIS scoring (r = 0.653, p < 0.001). Compared with EMG/NCV test, NSC score was most sensitive (85.96%) but least specific (77.03%); NIS score had lower sensitivity (59.65%) but best specificity (98.65%) and accuracy (81.68%). Both had high concordance with EMG/NCV test (x03BA; = 0.61). Sensitivity, specificity and accuracy of MNSI were highest (70.18, 98.65 and 80.15%) at the cutoff values of >1.0, >2.5 and >1.5, respectively (x03BA; = 0.58).

CONCLUSIONS

Both NSC and NIS were accurate and reliable diagnostic methods for DPN. The combined application of NSC and NIS was recommended in DPN diagnosis.

Assessment for ease of use and preference of a new prefilled insulin pen (FlexTouch Degludec U100/U200) versus the SoloSTAR insulin pen by patients with diabetes and healthcare professionals

OBJECTIVE

FlexTouch® (FT) is a new prefilled insulin pen with no push-button extension and a low injection force used to deliver several basal insulins, including insulin degludec across a wide dose range (1 - 80 units with FT 100 IU/ml [FT100] and 2 - 160 units with 200 IU/ml [FT200]). This study was carried out to evaluate whether the novel features of FT affect the preferences of the device among patients with diabetes and healthcare professionals compared with the widely used SoloSTAR® pen.

RESEARCH DESIGN AND METHODS

A multicenter, randomized, open-label, crossover study compared FT100 and FT200 with SoloSTAR. The study included patients with either type 1 (n = 22) or type 2 diabetes (n = 42), nurses (n = 32) and physicians (n = 32). Subjects were randomized to test each of the FT100, FT200 and SoloSTAR pens in a crossover set up. Subjects performed injections into a foam cushion at 4 - 6 different doses per device (2, 20, 40, 80, 120 and 160 IU).

RESULTS

Overall, a significantly higher proportion of subjects, including dexterity-impaired and pen-naive patients, preferred to use FT100 (93.0%; 119/128) and FT200 (91.4%; 117/128) compared with 2.3% (3/128) and 3.9% (5/128) who preferred SoloSTAR (p < 0.001), respectively.

CONCLUSION

FT100 and FT200 were preferred over SoloSTAR by nurses, physicians and patients with diabetes. This may be due to the novel design of FT, which improves ease of use, preference and confidence in delivering a complete, accurate dose of insulin, even at high doses.

Lower leg muscle strengthening does not redistribute plantar load in diabetic polyneuropathy: a randomised controlled trial

Background

Higher plantar pressures play an important role in the development of plantar foot ulceration in diabetic polyneuropathy and earlier studies suggest that higher pressures under the forefoot may be related to a decrease in lower leg muscle strength. Therefore, in this randomised controlled trial we evaluated whether lower-extremity strength training can reduce plantar pressures in diabetic polyneuropathy.

Methods

This study was embedded in an unblinded randomised controlled trial. Participants had diabetes and polyneuropathy and were randomly assigned to the intervention group (n = 48) receiving strength training during 24 weeks, or the control group (n = 46) receiving no intervention. Plantar pressures were measured in both groups at 0, 12, 24 and 52 weeks. A random intercept model was applied to evaluate the effects of the intervention on peak pressures and pressure–time-integrals, displacement of center-of-pressure and the forefoot to rearfoot pressure–time-integral-ratio.

Results

Plantar pressure patterns were not affected by the strength training. In both the intervention and control groups the peak pressure and the pressure–time-integral under the forefoot increased by 55.7 kPa (95% CI: 14.7, 96.8) and 2.0 kPa.s (95% CI: 0.9, 3.2) over 52 weeks, respectively. Both groups experienced a high number of drop-outs, mainly due to deterioration of health status and lower-extremity disabilities.

Conclusions

Plantar pressures under the forefoot increase progressively over time in people with diabetic polyneuropathy, but in this study were not affected by strength training. Future intervention studies should take this increase of plantar pressure into account and alternative interventions should be developed to reduce the progressive lower extremity problems in these patients.

Trial registration

This study was embedded in a clinical trial with trial number NCT00759265.

Painful and painless diabetic neuropathy: one disease or two?

Painful diabetic polyneuropathy (PDPN) is generally considered a variant of diabetic polyneuropathy (DPN) but the identification of distinctive aspects that characterize painful compared with painless DPN has however been addressed in many studies, mainly with the purpose of better understanding the mechanisms of neuropathic pain in the scenario of peripheral nerve damage of DPN, of determining risk markers for pain development, and also of recognizing who might respond to treatments. This review is aimed at examining available literature dealing with the issue of similarities and differences between painful and painless DPN in an attempt to respond to the question of whether painful and painless DPN are the same disease or not and to address the conundrum of why some people develop the insensate variety of DPN whilst others experience distressing pain. Thus, from the perspective of comparing painful with painless forms of DPN, this review considers the clinical correlates of PDPN, its distinctive framework of symptoms, signs, and nerve functional and structural abnormalities, the question of large and small fiber involvement, the peripheral pain mechanisms, the central processing of pain and some new insights into the pathogenesis of pain in peripheral polyneuropathies and PDPN.

Comparison of efficiencies of michigan neuropathy screening instrument, neurothesiometer, and electromyography for diagnosis of diabetic neuropathy

Aim. This study compares the effectiveness of Michigan Neuropathy Screening Instrument (MNSI), neurothesiometer, and electromyography (EMG) in detecting diabetic peripheral neuropathy in patients with diabetes type 2. Materials and Methods. 106 patients with diabetes type 2 treated at the outpatient clinic of Ankara Numune Education and Research Hospital Department of Endocrinology between September 2008 and May 2009 were included in this study. Patients were evaluated by glycemic regulation tests, MNSI (questionnaire and physical examination), EMG (for detecting sensorial and motor defects in right median, ulnar, posterior tibial, and bilateral sural nerves), and neurothesiometer (for detecting alterations in cold and warm sensations as well as vibratory sensations). Results. According to the MNSI score, there was diabetic peripheral neuropathy in 34 (32.1%) patients (score ≥2.5). However, when the patients were evaluated by EMG and neurothesiometer, neurological impairments were detected in 49 (46.2%) and 79 (74.5%) patients, respectively. Conclusion. According to our findings, questionnaires and physical examination often present lower diabetic peripheral neuropathy prevalence. Hence, we recommend that in the evaluation of diabetic patients neurological tests should be used for more accurate results and thus early treatment options to prevent neuropathic complications.

Diabetic neuropathy: clinical manifestations and current treatments

Diabetic peripheral neuropathy is a prevalent, disabling disorder. The most common manifestation is distal symmetrical polyneuropathy (DSP), but many patterns of nerve injury can occur. Currently, the only effective treatments are glucose control and pain management. While glucose control substantially decreases the development of neuropathy in those with type 1 diabetes, the effect is probably much smaller in those with type 2 diabetes. Evidence supports the use of specific anticonvulsants and antidepressants for pain management in patients with diabetic peripheral neuropathy. However, the lack of disease-modifying therapies for diabetic DSP makes the identification of new modifiable risk factors essential. Growing evidence supports an association between components of the metabolic syndrome, including prediabetes, and neuropathy. Studies are needed to further explore this association, which has implications for the development of new treatments for this common disorder.

Contribution of mitochondria to pain in diabetic neuropathy

Diabetes is a metabolic disease affecting approximately 300 million people worldwide. Neuropathy is one of its frequent complications, and may affect sensory, motor, and autonomic nerves. Its pathophysiology has not fully been elucidated. Several hypotheses have been proposed, and mitochondria have been suggested to play a significant role. This article reviews the mechanisms involved in mitochondrial dysfunction and development of diabetic neuropathy, consisting mainly of oxidative and inflammatory stress, changes in intracellular calcium regulation, apoptotic processes, and changes in mitochondrial structure and function that may lead to development of diabetic neuropathy.

Validation of DN4 as a screening tool for neuropathic pain in painful diabetic polyneuropathy

AIMS

DN4 (Douleur Neuropathique en 4 Questions) is a screening tool for neuropathic pain consisting of interview questions (DN4-interview) and physical tests. It has not formally been validated in diabetes. We evaluated the validity and diagnostic accuracy of DN4 and DN4-interview in identifying neuropathic pain of painful diabetic polyneuropathy.

METHODS

In 158 patients with diabetes, the presence of diabetic polyneuropathy and neuropathic pain was assessed using scoring system for symptoms and signs, quantitative sensory testing, nerve conduction studies, pain history, numerical rating scale, and Short-Form McGill Pain Questionnaire. Painful diabetic polyneuropathy was defined as the presence of diabetic polyneuropathy plus chronic neuropathic pain in the same area as neuropathic deficits. A blinded investigator performed DN4.

RESULTS

The DN4 score was significantly related to all the neurological and electrophysiological measurements and to Short-Form McGill Pain Questionnaire (ρ = 0.58, P < 0.0001). DN4 and DN4-interview scores showed a high diagnostic accuracy for painful diabetic polyneuropathy with areas under the receiver operating characteristic curve of 0.94 and 0.93, respectively. At the cut-off of 4, DN4 displayed sensitivity of 80%, specificity of 92%, positive predictive value (PPV) of 82%, negative predictive value (NPV) of 91%, and likelihood ratio for a positive result (LR(+) ) of 9.6. At the cut-off of 3, DN4-interview showed sensitivity and specificity of 84%, PPV of 71%, NPV of 92%, and LR(+) of 5.3.

CONCLUSIONS

This is the first validation study of DN4 for painful diabetic polyneuropathy, which supports its usefulness as both a screening tool for neuropathic pain in diabetes and a reliable component of the diagnostic work up for painful diabetic polyneuropathy.

Comparison of clinically relevant technical attributes of five insulin injection pens

BACKGROUND

Insulin injection pens are the predominant devices for insulin delivery in Europe and Japan because of their ease of use and convenience. This study compared clinically relevant technical attributes of durable insulin pens that are important to people with diabetes, specifically functions relating to cartridge-fitting, dose-setting, and dose-delivery on NovoPen® 4, ClikStar®, HumaPen Luxura®, Itango®, and Biosulin® Pen.

METHODS

Frequency components and duration of audible clicks on dose setting and injection were measured using audio equipment when setting and delivering 20 IU of insulin. To assess cartridge-fitting torque, each pen was attached to a torque gauge via the attached needle, and torque was measured with each 180° turn as the cartridge was screwed into the body of the pen. Rotary torque of the dose-setting dial was measured when setting the dose to the maximum dose unit of the pen. Injection force was measured when delivering 20 IU at 5 mm/s in a vertical position and at a tilt of 14.7° from vertical.

RESULTS

Audible clicks on dose-setting and dose-delivery were most distinguishable on NovoPen 4, while NovoPen 4 and ClikStar had generally lower cartridge-fitting torque and injection (both vertical and angled) force values.

CONCLUSION

Overall, the results showed that durable insulin pens such as NovoPen 4 have useful features related to assembly, dose-setting, and injection, which may facilitate ease of use for diabetes patients, particularly elderly patients and those with visual and/or manual dexterity impairments.

Needle with a novel attachment versus conventional screw-thread needles: a preference and usability test among adults with diabetes and impaired manual dexterity

BACKGROUND

NovoTwist(®) (Novo Nordisk A/S, Bagsværd, Denmark) is an insulin pen needle that features a novel attachment and detachment system. The aim of this test was to assess overall preference and handling of NovoTwist compared with conventional screw-thread needles in people with type 1 or type 2 diabetes.

METHODS

One hundred twenty adults with type 1 or type 2 diabetes and manual dexterity dysfunction who were currently self-injecting with an insulin pen were included in this open-label, randomized, crossover test. Participants were stratified according to the impact that manual dexterity problems had on their ability to inject insulin (1 = no effect at all; 4 = a lot), and those rated as 1 were excluded from subanalyses because of low numbers. Following instruction, participants attached the needle to Next Generation FlexPen(®) (Novo Nordisk A/S), made an injection into a foam cushion, and detached the needle; this process was repeated three times with NovoTwist and the participant's current screw-thread needle (or NovoFine(®) [Novo Nordisk A/S]) in a random order. Responses to questions on user experience with each needle were subsequently recorded on a 6-point rating scale (1 = very difficult; 6 = very easy).

RESULTS

Significantly more respondents had a preference for NovoTwist (79%) compared with the conventional screw-thread needles (21%, P < 0.001). Significantly more respondents preferred NovoTwist for both ease of attachment (80%, P < 0.001) and ease of detachment (74%, P < 0.001). Most respondents found NovoTwist the most appropriate needle for performing everyday injections (71%, P < 0.001).

CONCLUSIONS

Such preference by patients has a positive impact on the treatment of diabetes as NovoTwist may alleviate the burden of performing everyday injections through its ease of use.