Lipid Levels and Risk of Diabetic Polyneuropathy in 2 Danish Type 2 Diabetes Cohorts.

BACKGROUND AND OBJECTIVES: Reduction of blood lipids may aid in preventing diabetic polyneuropathy (DPN), but evidence remains conflicting. We investigated the association between lipid parameters and DPN risk in individuals with type 2 diabetes mellitus (T2DM). METHODS: We conducted a population-based cohort study of individuals with newly diagnosed T2DM and a cross-sectional study using a clinically recruited T2DM cohort. Triglycerides, high-density lipoprotein (HDL), low-density lipoprotein (LDL), and non-HDL cholesterol were measured in routine diabetes care. Each lipid parameter was categorized according to the latest cutoffs in clinical guidelines on dyslipidemia. DPN was assessed with validated hospital diagnosis codes in the population-based cohort and with the Michigan Neuropathy Screening Instrument questionnaire in the clinical cohort. We calculated hazard ratios (HRs) using Cox regression and prevalence ratios (PRs) using Poisson regression. RESULTS: We included 61,853 individuals in the population-based cohort (median age 63 [quartiles 54-72] years) and 4,823 in the clinical cohort (median age 65 [quartiles 57-72] years). The incidence rate of hospital-diagnosed DPN in the population-based cohort was 3.6 per 1000 person-years during a median follow-up of 7.3 years. Achieving guideline targets for HDL, LDL, and non-HDL cholesterol showed no association with DPN risk. By contrast, adjusted HRs (95% CI) for DPN were 1.02 (0.89-1.18) for triglyceride levels between 150 and 204 mg/dL (1.7-2.3 mmol/L) and 1.28 (1.13-1.45) for levels >204 mg/dL (2.3 mmol/L). In the clinical cohort with a DPN prevalence of 18%, DPN associated strongly with triglycerides >204 mg/dL (2.3 mmol/L) with an adjusted PR (95% CI) of 1.40 (1.21-1.62). The prevalence of DPN was modestly elevated for individuals with HDL cholesterol <39 mg/dL (1.0/1.3 mmol/L) in men and <50 mg/dL (1.3 mmol/L) in women (PR 1.13 [0.99-1.28]) and for individuals with non-HDL cholesterol >131 mg/dL (3.4 mmol/L) (PR 1.27 [1.05-1.52]). In both cohorts, spline models showed an increasing risk of DPN starting from triglyceride levels >124 mg/dL (1.4 mmol/L). All results were similar among statin users. DISCUSSION: High triglyceride levels are a strong DPN risk factor. Future intervention studies shall determine whether triglyceride reduction is more important for DPN prevention than reduction of other lipids.

Obesity-related neuropathy: the new epidemic.

PURPOSE OF REVIEW: To examine the evidence evaluating the association between obesity and neuropathy as well as potential interventions. RECENT FINDINGS: Although diabetes has long been associated with neuropathy, additional metabolic syndrome components, including obesity, are increasingly linked to neuropathy development, regardless of glycemic status. Preclinical rodent models as well as clinical studies are shedding light on the mechanisms of obesity-related neuropathy as well as challenges associated with slowing progression. Dietary and surgical weight loss and exercise interventions are promising, but more data is needed. SUMMARY: High-fat-diet rodent models have shown that obesity-related neuropathy is a product of excess glucose and lipid accumulation leading to inflammation and cell death. Clinical studies consistently demonstrate obesity is independently associated with neuropathy; therefore, likely a causal risk factor. Dietary weight loss improves neuropathy symptoms but not examination scores. Bariatric surgery and exercise are promising interventions, but larger, more rigorous studies are needed. Further research is also needed to determine the utility of weight loss medications and ideal timing for obesity interventions to prevent neuropathy.

Prevalence and Risk Factors of Distal Symmetric Polyneuropathy Among Predominantly Non-Hispanic Black, Low-Income Patients.

BACKGROUND AND OBJECTIVES: Distal symmetric polyneuropathy (DSP) is a disabling, often painful condition associated with falls and reduced quality of life. Non-Hispanic Black people and people with low income are underrepresented in existing DSP studies; therefore, it is unknown whether data accurately reflect the prevalence, risk factors, and burden of disease in these populations. METHODS: Patients older than 40 years presenting to an outpatient internal medicine clinic predominantly serving Medicaid patients in Flint, Michigan, were enrolled in a cross-sectional study. Demographics, clinical characteristics, including medication use, anthropomorphic measurements, fasting lipids, and hemoglobin A1c were collected. DSP was defined using the modified Toronto Clinical Neuropathy Score (mTCNS). Multivariable logistic regression was performed to model DSP and undiagnosed DSP as a function of potential risk factors age, metabolic syndrome, and race. DSP burden was measured using Peripheral Neuropathy Quality of Life Instrument-97. RESULTS: Two hundred participants were enrolled, and 169 (85%) completed all data collection. The population was 55% female of mean age (SD) 58.2 years (10.4) and 69% non-Hispanic Black. Among the population, 50% had diabetes, 67% had metabolic syndrome, and 47% had a household income <$20,000. DSP was present in 73% of the population, of which 75% were previously undiagnosed. Neuropathic pain was documented in 57% of participants with DSP. DSP based on mTCNS criteria was associated with older age (odds ratio [OR] 1.1 [95% confidence interval (CI) 1.03-1.2]) and metabolic syndrome (OR 4.4 [1.1-18.1]). Non-Hispanic Black participants had lower odds of DSP (OR 0.1 [0.01-0.4]) than non-Hispanic White and Hispanic participants. DSP burden was high, including increased pain, health-related worry, and poorer quality of life (all p < 0.001). DISCUSSION: DSP is extremely common and often underrecognized in this predominantly non-Hispanic Black, low-income population and leads to substantial disease burden. Metabolic syndrome is a highly prevalent, modifiable risk factor in this population that should be managed to lower DSP prevalence.

Burden of Neurologic Health Care and Incident Neurologic Diagnoses in the Year After COVID-19 or Influenza Hospitalization.

BACKGROUND AND OBJECTIVE: Following the outbreak of viral infections from the severe acute respiratory syndrome coronavirus 2 virus in 2019 (coronavirus disease 2019 [COVID-19]), reports emerged of long-term neurologic sequelae in survivors. To better understand the burden of neurologic health care and incident neurologic diagnoses in the year after COVID-19 vs influenza, we performed an analysis of patient-level data from a large collection of electronic health records (EMR). METHODS: We acquired deidentified data from TriNetX, a global health research network providing access to EMR data. We included individuals aged 18 years or older during index event, defined as hospital-based care for COVID-19 (from April 1, 2020, until November 15, 2021) or influenza (from 2016 to 2019). The study outcomes were subsequent health care encounters over the following year for 6 neurologic diagnoses including migraine, epilepsy, stroke, neuropathy, movement disorders, and dementia. We also created a composite of the 6 diagnoses as an incident event, which we call "incident neurologic diagnoses." We performed a 1:1 complete case nearest-neighbor propensity score match on age, sex, race/ethnicity, marital status, US census region patient residence, preindex years of available data, and Elixhauser comorbidity score. We fit time-to-event models and reported hazard ratios for COVID-19 vs influenza infection. RESULTS: After propensity score matching, we had a balanced cohort of 77,272 individuals with COVID-19 and 77,272 individuals with influenza. The mean age was 51.0 ± 19.7 years, 57.7% were female, and 41.5% were White. Compared with patients with influenza, patients with COVID-19 had a lower risk of subsequent care for migraine (HR 0.645, 95% CI 0.604-0.687), epilepsy (HR 0.783, 95% CI 0.727-0.843), neuropathies (HR 0.567, 95% CI 0.532-0.604), movement disorders (HR 0.644, 95% CI 0.598-0.693), stroke (HR 0.904, 95% CI 0.845-0.967), or dementia (HR 0.931, 95% CI 0.870-0.996). Postinfection incident neurologic diagnoses were observed in 2.79% of the COVID-19 cohort vs 4.91% of the influenza cohort (HR 0.618, 95% CI 0.582-0.657). DISCUSSION: Compared with a matched cohort of adults with a hospitalization or emergency department visit for influenza infection, those with COVID-19 had significantly fewer health care encounters for 6 major neurologic diagnoses over a year of follow-up. Furthermore, we found that COVID-19 infection was associated with a lower risk of an incident neurologic diagnosis in the year after infection.

Streamlining Prior Authorization to Improve Care.

This Viewpoint addresses the challenges of prior authorization: decreased access, delayed care, decreased patient satisfaction and outcomes, and increased clinician burnout.

Cost and utilization of healthcare services for persons with diabetes.

AIMS: Describe and compare healthcare costs and utilization for insured persons with type 1 diabetes (T1D), type 2 diabetes (T2D), and without diabetes in the United States. METHODS: Using a nationally representative healthcare claims database, we identified matched persons with T1D, T2D, and without diabetes using a propensity score quasi-randomization technique. In each year between 2009 and 2018, we report costs (total and out-of-pocket) and utilization for all healthcare services and those specific to medications, diabetes-related supplies, visits to providers, hospitalizations, and emergency department visits. RESULTS: In 2018, we found out-of-pocket costs and total costs were highest for persons with T1D (out-of-pocket: $2,037.2, total: $25,652.0), followed by T2D (out-of-pocket: $1,543.3, total: $22,408.1), and without diabetes (out-of-pocket: $1,122.7, total: $14,220.6). From 2009 to 2018, out-of-pocket costs were increasing for persons with T1D(+6.5 %) but decreasing for T2D (-7.5 %) and without diabetes (-2.3 %). Medication costs made up the largest proportion of out-of-pocket costs regardless of diabetes status (T1D: 51.4 %, T2D: 55.4 %,without diabetes: 51.1 %). CONCLUSIONS: Given the substantial out-of-pocket costs for people with diabetes, especially for those with T1D, providers should screen all persons with diabetes for financial toxicity (i.e., wide-ranging problems stemming from healthcare costs). In addition, policies that aim to lower out-of-pocket costs of cost-effective diabetes related healthcare are needed with a particular focus on medications.

Diabetic Neuropathies.

OBJECTIVE: This article provides an up-to-date review of the diagnosis and management of the most common neuropathies that occur in patients with diabetes. LATEST DEVELOPMENTS: The prevalence of diabetes continues to grow worldwide and, as a result, the burden of diabetic neuropathies is also increasing. Most diabetic neuropathies are caused by hyperglycemic effects on small and large fiber nerves, and glycemic control in individuals with type 1 diabetes reduces neuropathy prevalence. However, among people with type 2 diabetes, additional factors, particularly metabolic syndrome components, play a role and should be addressed. Although length-dependent distal symmetric polyneuropathy is the most common form of neuropathy, autonomic syndromes, particularly cardiovascular autonomic neuropathy, are associated with increased mortality, whereas lumbosacral radiculoplexus neuropathy and treatment-induced neuropathy cause substantial morbidity. Recent evidence-based guidelines have updated the recommended treatment options to manage pain associated with distal symmetric polyneuropathy of diabetes. ESSENTIAL POINTS: Identifying and appropriately diagnosing the neuropathies of diabetes is key to preventing progression. Until better disease-modifying therapies are identified, management remains focused on diabetes and metabolic risk factor control and pain management.

Patient Travel Distance to Neurologist Visits.

BACKGROUND AND OBJECTIVES: The density of neurologists within a given geographic region varies greatly across the United States. We aimed to measure patient travel distance and travel time to neurologist visits, across neurologic conditions and subspecialties. Our secondary goal was to identify factors associated with long-distance travel for neurologic care. METHODS: We performed a cross-sectional analysis using a 2018 Medicare sample of patients with at least 1 outpatient neurologist visit. Long-distance travel was defined as driving distance ≥50 miles 1-way to the visit. Travel time was measured as driving time in minutes. Multilevel generalized linear mixed models with logistic link function, which accounted for clustering of patients within hospital referral region and allowed modeling of region-specific random effects, were used to determine the association of patient and regional characteristics with long-distance travel. RESULTS: We identified 563,216 Medicare beneficiaries with a neurologist visit in 2018. Of them, 96,213 (17%) traveled long distance for care. The median driving distance and time were 81.3 (interquartile range [IQR]: 59.9-144.2) miles and 90 (IQR: 69-149) minutes for patients with long-distance travel compared with 13.2 (IQR: 6.5-23) miles and 22 (IQR: 14-33) minutes for patients without long-distance travel. Comparing across neurologic conditions, long-distance travel was most common for nervous system cancer care (39.6%), amyotrophic lateral sclerosis [ALS] (32.1%), and MS (22.8%). Many factors were associated with long-distance travel, most notably low neurologist density (first quintile: OR 3.04 [95% CI 2.41-3.83] vs fifth quintile), rural setting (4.89 [4.79-4.99]), long-distance travel to primary care physician visit (3.6 [3.51-3.69]), and visits for ALS and nervous system cancer care (3.41 [3.14-3.69] and 5.27 [4.72-5.89], respectively). Nearly one-third of patients bypassed the nearest neurologist by 20+ miles, and 7.3% of patients crossed state lines for neurologist care. DISCUSSION: We found that nearly 1 in 5 Medicare beneficiaries who saw a neurologist traveled ≥50 miles 1-way for care, and travel burden was most common for lower-prevalence neurologic conditions that required coordinated multidisciplinary care. Important potentially addressable predictors of long-distance travel were low neurologist density and rural location, suggesting interventions to improve access to care such as telemedicine or neurologic subspecialist support to local neurologists. Future work should evaluate differences in clinical outcomes between patients with long-distance travel and those without.

Association between brain health outcomes and metabolic risk factors in persons with diabetes.

We performed a cross-sectional study to determine associations between cognition and MRI-derived brain outcomes, with obesity, diabetes duration, and metabolic risk factors in 51 Pima American Indians with longstanding type 2 diabetes (T2d) (mean [SD] age: 48.4 [11.3] years, T2d duration: 20.1 [9.1] years). Participants had similar cognition (NIH Toolbox Cognition Battery composite: 45.3 [9.8], p = 0.64, n = 51) compared to normative data. T2d duration, but not other metabolic risk factors, associated with decreased cortical thickness (Point Estimate (PE): -0.0061, 95%CI: -0.0113, -0.0009, n = 45), gray matter volume (PE: -830.39, 95%CI: -1503.14, -157.64, n = 45), and increased white matter hyperintensity volume (PE: 0.0389, 95%CI: 0.0049, 0.0729, n = 45).

Prescription Opioid Initiation for Neuropathy, Headache, and Low Back Pain: A US Population-based Medicare Study.

Neuropathy, headache, and low back pain (LBP) are common conditions requiring pain management. Yet little is known regarding whether access to specialists impacts opioid prescribing. We aimed to identify factors associated with opioid initiation among opioid-naïve older adults and evaluate how access to particular specialists impacts prescribing. This retrospective cohort study used a 20% Medicare sample from 2010 to 2017. Opioid initiation was defined as a first opioid prescription filled within 12 months after a diagnosis encounter. Disease-related opioid initiation was defined as a first opioid prescription filled within 7 days following a disease-specific claim. Logistic regression using generalized estimating equations was used to determine the association of patient demographics, provider types, and regional physician specialty density with disease-related opioid initiation, accounting for within-region correlation. We found opioid initiation steadily declined from 2010 to 2017 (neuropathy: 26-19%, headache: 31-20%, LBP: 45-32%), as did disease-related opioid initiation (4-3%, 12-7%, 29-19%) and 5 to 10% of initial disease-related prescriptions resulted in chronic opioid use within 12 months of initiation. Certain specialist visits were associated with a lower likelihood of disease-related opioid initiation compared with primary care. Residence in high neurologist density regions had a lower likelihood of disease-related opioid initiation (headache odds ratio [OR] .76 [95% CI: .63-.92]) and LBP (OR .7 [95% CI: .61-.81]) and high podiatrist density regions for neuropathy (OR .56 [95% CI: .41-.78]). We found that specialist visits and greater access to specialists were associated with a lower likelihood of disease-related opioid initiation. These data could inform strategies to perpetuate reductions in opioid use for these common pain conditions. PERSPECTIVE: This article presents how opioid initiation for opioid-naïve patients with newly diagnosed neuropathy, headache, and LBP varies across providers. Greater access to certain specialists decreased the likelihood of opioid initiation. Future work may consider interventions to support alternative treatments and better access to specialists in low-density regions.

The Prevalence of Polyneuropathy in Type 2 Diabetes Subgroups Based on HOMA2 Indices of ß-Cell Function and Insulin Sensitivity.

OBJECTIVE: Metabolic syndrome components may cumulatively increase the risk of diabetic polyneuropathy (DPN) in type 2 diabetes mellitus (T2DM) patients, driven by insulin resistance and hyperinsulinemia. We investigated the prevalence of DPN in three T2DM subgroups based on indices of ß-cell function and insulin sensitivity. RESEARCH DESIGN AND METHODS: We estimated ß-cell function (HOMA2-B) and insulin sensitivity (HOMA2-S) in 4,388 Danish patients with newly diagnosed T2DM. Patients were categorized into subgroups of hyperinsulinemic (high HOMA2-B, low HOMA2-S), classical (low HOMA2-B, low HOMA2-S), and insulinopenic (low HOMA2-B, high HOMA2-S) T2DM. After a median follow-up of 3 years, patients filled the Michigan Neuropathy Screening Instrument questionnaire (MNSIq) to identify DPN (score ≥ 4). We used Poisson regression to calculate adjusted prevalence ratios (PRs) for DPN, and spline models to examine the association with HOMA2-B and HOMA2-S. RESULTS: A total of 3,397 (77%) patients filled in the MNSIq. The prevalence of DPN was 23% among hyperinsulinemic, 16% among classical, and 14% among insulinopenic patients. After adjusting for demographics, diabetes duration and therapy, lifestyle behaviors, and metabolic syndrome components (waist circumference, triglycerides, HDL cholesterol, hypertension, and HbA1c), the PR of DPN was 1.35 (95% CI 1.15-1.57) for the hyperinsulinemic compared with the classical patients. In spline analyses, we observed a linear relation of higher DPN prevalence with increasing HOMA2-B, independent of both metabolic syndrome components and HOMA2-S. CONCLUSIONS: Hyperinsulinemia marked by high HOMA2-B is likely an important risk factor for DPN beyond metabolic syndrome components and insulin resistance. This should be considered when developing interventions to prevent DPN.

The effect of surgical weight loss on diabetes complications in individuals with class II/III obesity.

AIMS/HYPOTHESIS: The aim of this study was to determine the effect of bariatric surgery on diabetes complications in individuals with class II/III obesity (BMI > 35 kg/m2). METHODS: We performed a prospective cohort study of participants with obesity who underwent bariatric surgery. At baseline and 2 years following surgery, participants underwent metabolic phenotyping and diabetes complication assessments. The primary outcomes for peripheral neuropathy (PN) were a change in intra-epidermal nerve fibre density (IENFD, units = fibres/mm) at the distal leg and proximal thigh, the primary outcome for cardiovascular autonomic neuropathy (CAN) was a change in the expiration/inspiration (E/I) ratio, and the primary outcome for retinopathy was a change in the mean deviation on frequency doubling technology testing. RESULTS: Among 127 baseline participants, 79 completed in-person follow-up (age 46.0 ± 11.3 years [mean ± SD], 73.4% female). Participants lost a mean of 31.0 kg (SD 18.4), and all metabolic risk factors improved except for BP and total cholesterol. Following bariatric surgery, one of the primary PN outcomes improved (IENFD proximal thigh, +3.4 ± 7.8, p<0.01), and CAN (E/I ratio -0.01 ± 0.1, p=0.89) and retinopathy (deviation -0.2 ± 3.0, p=0.52) were stable. Linear regression revealed that a greater reduction in fasting glucose was associated with improvements in retinopathy (mean deviation point estimate -0.7, 95% CI -1.3, -0.1). CONCLUSIONS/INTERPRETATION: Bariatric surgery may be an effective approach to reverse PN in individuals with obesity. The observed stability of CAN and retinopathy may be an improvement compared with the natural progression of these conditions; however, controlled trials are needed.

Limited diagnostic utility of serologic testing for neurologic manifestations of systemic disease in the evaluation of suspected multiple sclerosis: A single-center observational study.

BACKGROUND: The clinical evaluation of a new diagnosis of MS typically includes serologic testing to evaluate for its many mimics, yet there is little data to guide approaches to such testing. OBJECTIVE: To evaluate for the frequency and clinical significance of serologic testing for MS diagnostic evaluations. METHODS: In a single MS subspeciality center retrospective study, new patient evaluations for MS over the course of a year were identified, and the results of serologic testing and diagnostic evaluation extracted. Retrospective longitudinal diagnostic assessment was performed to confirm the accuracy of initial serological testing assessments. RESULTS: 150 patients had 823 serologic tests. 40 (5%) tests were positive, and resulted in 117 additional serologic tests, 10 radiographs, and 2 biopsies. 77 (51%) patients were diagnosed with a non-demyelinating disorder. Serologic testing results did not change any diagnosis, yet in some patients, it resulted in unnecessary additional testing and diagnostic delay. CONCLUSIONS: Serologic testing in the clinical assessment for routine MS resulted in unnecessary diagnostic delay, additional testing, and considerable healthcare cost.

Costs and Utilization of New-to-Market Neurologic Medications.

BACKGROUND AND OBJECTIVES: The objective of this study was to compare the utilization and costs (total and out-of-pocket) of new-to-market neurologic medications with existing guideline-supported neurologic medications over time. METHODS: We used a healthcare pharmaceutical claims database (from 2001 to 2019) to identify patients with both a diagnosis of 1 of 11 separate neurologic conditions and either a new-to-market medication or an existing guideline-supported medication for that condition. Neurologic conditions included orthostatic hypotension, spinal muscular atrophy, Duchenne disease, Parkinson disease, multiple sclerosis, amyotrophic lateral sclerosis, myasthenia gravis, Huntington disease, tardive dyskinesia, transthyretin amyloidosis, and migraine. New-to-market medications were defined as all neurologic medications approved by the US Food and Drug Administration (FDA) between 2014 and 2018. In each year, we determined the median out-of-pocket and standardized total costs for a 30-day supply of each medication. We also measured the proportion of patients receiving new-to-market medications compared with all medications specific for the relevant condition. RESULTS: We found that the utilization of most new-to-market medications was small (<20% in all but 1 condition), compared with existing, guideline-supported medications. The out-of-pocket and standardized total costs were substantially larger for new-to-market medications. The median (25th percentile, 75th percentile) out-of-pocket costs for a 30-day supply in 2019 were largest for edaravone ($712.8 [$59.8-$802.0]) and eculizumab ($91.1 [$3.0-$3,216.4]). For new-to-market medications, the distribution of out-of-pocket costs was highly variable and the trends over time were unpredictable compared with existing guideline-supported medications. DISCUSSION: Despite the increasing number of FDA-approved neurologic medications, utilization of newly approved medications in the privately insured population remains small. Given the high costs and similar efficacy for most of the new medications, limited utilization may be appropriate. However, for new medications with greater efficacy, future studies are needed to determine whether high costs are a barrier to utilization.

From COVID-19 to Green Recovery with natural capital accounting.

The COVID-19 pandemic and related social and economic emergencies induced massive public spending and increased global debt. Economic recovery is now an opportunity to rebuild natural capital alongside financial, physical, social and human capital, for long-term societal benefit. Yet, current decision-making is dominated by economic imperatives and information systems that do not consider society's dependence on natural capital and the ecosystem services it provides. New international standards for natural capital accounting (NCA) are now available to integrate environmental information into government decision-making. By revealing the effects of policies that influence natural capital, NCA supports identification, implementation and monitoring of Green Recovery pathways, including where environment and economy are most positively interlinked.

Diagnostic characteristics of nerve conduction study parameters for vasculitic neuropathy.

INTRODUCTION/AIMS: In vasculitic neuropathy (VN), a 50% side-to-side difference in the amplitude of compound muscle action potentials and sensory nerve action potentials is considered meaningful, but unequivocal evidence is lacking. The aim of this study is to characterize electrodiagnostic features that best distinguish VN from other axonal polyneuropathies. METHODS: We conducted a case-control study between January 2000 and April 2021. We reviewed the records of patients with VN who had bilateral nerve conduction studies (NCS) and evaluated different electrodiagnostic models to help distinguish VN from non-inflammatory axonal polyneuropathies. RESULTS: We identified 82 cases, and 174 controls with non-inflammatory axonal neuropathies. The amplitude percent difference Z-score model showed the best discriminatory capability between cases and controls (area under the curve [AUC] 0.87; 95% confidence interval [CI] 0.82, 0.93), and the number of nerves tested did not significantly influence the model. Individually, the ulnar motor nerve (AUC 0.86; 95% CI 0.77, 0.94) and median motor nerve (AUC 0.85; 95% CI 0.77, 0.94) showed the best discriminatory capability. A 50% amplitude difference between at least two bilateral nerves, either in the upper (AUC 0.85; 95% CI 0.77, 0.93) or lower (AUC 0.79; 95% CI 0.71, 0.87) extremity showed good discriminatory threshold for detecting VN. DISCUSSION: The best electrodiagnostic criteria for VN utilizes z-scores of percent differences in nerve amplitudes, but this approach may be difficult to implement at the bedside. Alternately, a 50% amplitude difference in at least two nerves is a reasonable approximation.

Patient and health care provider knowledge of diabetes and diabetic microvascular complications: a comprehensive literature review.

Diabetic retinopathy, neuropathy, and nephropathy occur in more than 50% of people with diabetes, contributing substantially to morbidity and mortality. Patient understanding of these microvascular complications is essential to ensure early recognition and treatment of these sequalae as well as associated symptoms, yet little is known about patient knowledge of microvascular sequalae. In this comprehensive literature review, we provide an overview of existing knowledge regarding patient knowledge of diabetes, retinopathy, neuropathy, and nephropathy. We also discuss health care provider's knowledge of these sequalae given that patients and providers must work together to achieve optimal care. We evaluated 281 articles on patient and provider knowledge of diabetic retinopathy, neuropathy, and nephropathy as well as predictors of improved knowledge and screening practices. Results demonstrated that patient and provider knowledge of microvascular sequalae varied widely between studies, which may reflect sociocultural or methodologic differences. Knowledge assessment instruments varied between studies with limited validation data and few studies controlled for confounding. Generally, improved patient knowledge was associated with greater formal education, longer diabetes duration, and higher socioeconomic status. Fewer studies examined provider knowledge of sequalae, yet these studies identified multiple misconceptions regarding appropriate screening practices for microvascular complications and the need to screen patients who are asymptomatic. Further investigations are needed that use well validated measures, control for confounding, and include diverse populations. Such studies will allow identification of patients and providers who would benefit from interventions to improve knowledge of microvascular complications and, ultimately, improve patient outcomes.