Older age of childhood type 1 diabetes onset is associated with islet autoantibody positivity >30 years later: the Pittsburgh Epidemiology of Diabetes Complications Study.

AIMS: To examine the association between islet autoantibody positivity and clinical characteristics, residual ß-cell function (C-peptide) and prevalence of complications in a childhood-onset (age <17 years), long-duration (≥32 years) type 1 diabetes cohort. METHODS: Islet autoantibodies (glutamic acid decarboxylase, insulinoma-associated protein 2 and zinc transporter-8 antibodies) were measured in the serum of participants who attended the 2011-2013 Pittsburgh Epidemiology of Diabetes Complications study follow-up examination (n=177, mean age 51 years, diabetes duration 43 years). RESULTS: Prevalences of islet autoantibodies were: glutamic acid decarboxylase, 32%; insulinoma-associated protein 2, 22%; and zinc transporter-8, 4%. Positivity for each islet autoantibody was associated with older age at diabetes onset (glutamic acid decarboxylase antibodies, P=0.03; insulinoma-associated protein 2 antibodies, P=0.001; zinc transporter-8 antibodies, P<0.0001). Older age at onset was also associated with an increasing number of autoantibodies (P = 0.001). Glutamic acid decarboxylase antibody positivity was also associated with lower HbA1c (P = 0.02), insulinoma-associated protein 2 antibody positivity was associated with lower prevalence of severe hypoglycaemic episodes (P=0.02) and both distal and autonomic neuropathy (P=0.04 for both), and zinc transporter-8 antibody positivity was associated with higher total and LDL cholesterol (P=0.01). No association between autoantibody positivity and C-peptide was observed. CONCLUSIONS: The strong association between islet autoantibody positivity and older age at type 1 diabetes onset supports the hypothesis of a less aggressive, and thus more persistent, immune process in those with older age at onset. This observation suggests that there may be long-term persistence of heterogeneity in the underlying autoimmune process.

Predictors of early renal function decline in adults with Type 1 diabetes: the Coronary Artery Calcification in Type 1 Diabetes and the Pittsburgh Epidemiology of Diabetes Complications studies.

AIM: Diabetic kidney disease is one of the leading complications of Type 1 diabetes, but its prediction remains a challenge. We examined predictors of rapid decline in estimated GFR (eGFR) in two Type 1 diabetes cohorts: the Coronary Artery Calcification in Type 1 Diabetes (CACTI) and the Pittsburgh Epidemiology of Diabetes Complications (EDC). METHODS: A select subset of participants (CACTI: n = 210 and EDC: n = 98) diagnosed before 17 years of age with Type 1 diabetes duration ≥ 7 years, and follow-up data on eGFR by CKD-EPI creatinine for up to 8 years were included in the analyses. Early renal function decline was defined as annual decline in eGFR ≥ 3 ml/min/1.73 m2 , and normal age-related decline as eGFR ≤ 1 ml/min/1.73 m2 . Parallel logistic regression models were constructed in the two cohorts. RESULTS: Early renal function decline incidence was 36% in CACTI and 41% in EDC. In both cohorts, greater baseline eGFR (CACTI: OR 3.12, 95% CI 1.97-5.05; EDC: OR 1.92, 95% CI 1.17-3.15 per 10 ml/min/1.73 m2 ) and log albumin-to-creatinine (ACR) (CACTI: OR 3.24, 95% CI 1.80-5.83; EDC: OR 1.87, 95% CI 1.18-2.96 per 1 unit) predicted greater odds of early renal function decline in fully adjusted models. Conversely, ACE inhibition predicted lower odds of early renal function decline in women in CACTI, but similar relationships were not observed in women in EDC. CONCLUSIONS: A substantial proportion of people with Type 1 diabetes in the EDC and CACTI cohorts experienced early renal function decline over time. ACE inhibition appeared to be protective only in women in CACTI where the prevalence of its use was twofold higher compared with the EDC.

Modulation of the CO2 fixation in dinickel azacryptands.

While bimetallic azacryptands are known to selectively coordinate CO2, there is little knowledge on how different substitution patterns of the azacryptand cage structure influence CO2 coordination. Stopped-flow UV-vis spectroscopy, electrochemical analysis and DFT calculations were performed on a series of dinickel azacryptands and showed different rates of CO2 coordination to the complexes. We herein present data showing that the different flexibility of the azacryptands is directly responsible for the difference in the CO2 uptake capability of dinickel azacryptand complexes.

Antivibration gloves: effects on vascular and sensorineural function, an animal model.

Anti-vibration gloves have been used to block the transmission of vibration from powered hand tools to the user, and to protect users from the negative health consequences associated with exposure to vibration. However, there are conflicting reports as to the efficacy of gloves in protecting workers. The goal of this study was to use a characterized animal model of vibration-induced peripheral vascular and nerve injury to determine whether antivibration materials reduced or inhibited the effects of vibration on these physiological symptoms. Rats were exposed to 4 h of tail vibration at 125 Hz with an acceleration 49 m/s(2). The platform was either bare or covered with antivibrating glove material. Rats were tested for tactile sensitivity to applied pressure before and after vibration exposure. One day following the exposure, ventral tail arteries were assessed for sensitivity to vasodilating and vasoconstricting factors and nerves were examined histologically for early indicators of edema and inflammation. Ventral tail artery responses to an α2C-adrenoreceptor agonist were enhanced in arteries from vibration-exposed rats compared to controls, regardless of whether antivibration materials were used or not. Rats exposed to vibration were also less sensitive to pressure after exposure. These findings are consistent with experimental findings in humans suggesting that antivibration gloves may not provide protection against the adverse health consequences of vibration exposure in all conditions. Additional studies need to be done examining newer antivibration materials.

Femoral-gluteal adiposity is not associated with insulin sensitivity in type 1 diabetes.

AIMS: To quantify and compare associations between femoral-gluteal adiposity and insulin sensitivity in adults with Type 1 diabetes mellitus with adults with normal glucose tolerance. METHODS: Individuals with Type 1 diabetes (n = 28) were recruited from the Pittsburgh Epidemiology of Diabetes Complication study, a 24-year prospective study of childhood-onset diabetes, and compared cross-sectionally with individuals with normal glucose tolerance (n = 56) of similar age, sex and BMI. Insulin sensitivity was defined as whole-body glucose disposal measured by hyperinsulinaemic-euglycaemic clamps. Adiposity was quantified by dual energy X-ray absorptiometry. RESULTS: Individuals with Type 1 diabetes exhibited lower insulin sensitivity (5.8 vs. 8.2 mg min(-1) kg fat-free mass(-1), P < 0.01), lower total fat mass (20.1 vs. 29.0 kg, P < 0.001) and lower proportional leg fat mass (36.0 vs.37.7%, P = 0.03), but similar proportional trunk fat (% trunk fat mass) compared with individuals with normal glucose tolerance. Overall, results from linear regression demonstrated that higher % leg fat mass (P < 0.01) and lower % trunk fat mass (P < 0.01) were independently associated with lower insulin sensitivity after adjustments for age, sex, height, total fat mass (kg) and diabetes status. Higher % leg fat mass was independently associated with higher insulin sensitivity in individuals with normal glucose tolerance (P < 0.01) after similar adjustment; significant associations were not observed in Type 1 diabetes. CONCLUSIONS: Reduced insulin sensitivity is a prominent feature of Type 1 diabetes and is associated with total and abdominal adiposity. Compared with adults with normal glucose tolerance, leg fat mass does not show any positive association with insulin sensitivity in Type 1 diabetes.

Phase II screening trial of lithium carbonate in amyotrophic lateral sclerosis: examining a more efficient trial design.

OBJECTIVE: To use a historical placebo control design to determine whether lithium carbonate slows progression of amyotrophic lateral sclerosis (ALS). METHODS: A phase II trial was conducted at 10 sites in the Western ALS Study Group using similar dosages (300-450 mg/day), target blood levels (0.3-0.8 mEq/L), outcome measures, and trial duration (13 months) as the positive trial. However, taking riluzole was not a requirement for study entry. Placebo outcomes in patients matched for baseline features from a large database of recent clinical trials, showing stable rates of decline over the past 9 years, were used as historical controls. RESULTS: The mean rate of decline of the ALS Functional Rating Scale-Revised was greater in 107 patients taking lithium carbonate (-1.20/month, 95% confidence interval [CI] -1.41 to -0.98) than that in 249 control patients (-1.01/month, 95% CI -1.11 to -0.92, p = 0.04). There were no differences in secondary outcome measures (forced vital capacity, time to failure, and quality of life), but there were more adverse events in the treated group. CONCLUSIONS: The lack of therapeutic benefit and safety concerns, taken together with similar results from 2 other recent trials, weighs against the use of lithium carbonate in patients with ALS. The absence of drift over time and the availability of a large database of patients for selecting a matched historical control group suggest that use of historical controls may result in more efficient phase II trials for screening putative ALS therapeutic agents. CLASSIFICATION OF EVIDENCE: This study provided Class IV evidence that lithium carbonate does not slow the rate of decline of function in patients with ALS over 13 months.

In the absence of renal disease, 20 year mortality risk in type 1 diabetes is comparable to that of the general population: a report from the Pittsburgh Epidemiology of Diabetes Complications Study.

AIMS/HYPOTHESIS: The FinnDiane Study has reported that mortality in type 1 diabetes is not increased over a 7 year follow-up in the absence of renal disease (RD). Using the Pittsburgh Epidemiology of Diabetes Complications (EDC) Study population (n = 658) of childhood-onset type 1 diabetes (age <17 years), the present study sought to replicate and expand these findings to a 20 year follow-up (as of 1 January 2008) and examine cause of death by renal status. METHODS: At baseline (1986-1988), mean age and duration of diabetes were 28 and 19 years, respectively. RD was defined as an albumin excretion rate ≥20 µg/min from multiple samples and grouped as microalbuminuria (MA; 20-200 µg/min), overt nephropathy (ON; >200 µg/min), or end stage renal disease (ESRD; dialysis or renal transplantation). RESULTS: At baseline, 311 (47.3%) individuals had RD (MA 21.3%, ON 22.2% and ESRD 3.8%). During a median 20 year follow-up, there were 152 deaths (23.1%). Mortality was 6.2 (95% CI 5.2-7.2) times higher than expected, with standardised mortality ratios of 2.0 (1.2-2.8) for normoalbuminuria (NA); 6.4 (4.4-8.4) for MA; 12.5 (9.5-15.4) for ON; and 29.8 (16.8-42.9) for ESRD. Excluding those (n = 64) with NA who later progressed to RD, no significant excess mortality was observed in the remaining NA group (1.2, 0.5-1.9), whose deaths were largely unrelated to diabetes. CONCLUSIONS/INTERPRETATION: These data confirm the importance of RD, including persistent microalbuminuria, as a marker of mortality risk and suggest that type 1 diabetes patients without renal disease achieve long-term survival comparable to the general population.

Temporal patterns in overweight and obesity in Type 1 diabetes.

AIMS: Time trends in overweight and obesity in the general population have been well documented; however, temporal patterns in Type 1 diabetes (T1DM) have not been thoroughly investigated. We therefore assessed temporal patterns in overweight and obesity and predictors of weight change in 589 individuals from the Pittsburgh Epidemiology of Diabetes Complications Study, a cohort of childhood-onset T1DM. METHODS: Participants were first seen in 1986-1988, when mean age and diabetes duration were 29 and 20 years, respectively, and biennially thereafter for 18 years. Overweight was defined as 25.0or=30.0 kg/m2. RESULTS: At baseline, the prevalence of overweight and obesity were 28.6% and 3.4%, respectively. After 18 years' follow-up, the prevalence of overweight increased by 47% while the prevalence of obesity increased sevenfold. Seven per cent were on intensive insulin therapy (>or=3 insulin injections per day or on insulin pump) at baseline; by 2004-2007, this was 82%. Predictors of weight change were a higher baseline HbA1c, symptomatic autonomic neuropathy (inversely), overt nephropathy (inversely), and going onto intensive insulin therapy during follow-up. CONCLUSIONS: These data demonstrate dramatic weight gain in T1DM and underscore the complexity of weight change in this disease.

Practice parameter update: the care of the patient with amyotrophic lateral sclerosis: drug, nutritional, and respiratory therapies (an evidence-based review): report of the Quality Standards Subcommittee of the American Academy of Neurology.

OBJECTIVE: To systematically review evidence bearing on the management of patients with amyotrophic lateral sclerosis (ALS). METHODS: The authors analyzed studies from 1998 to 2007 to update the 1999 practice parameter. Topics covered in this section include slowing disease progression, nutrition, and respiratory management for patients with ALS. RESULTS: The authors identified 8 Class I studies, 5 Class II studies, and 43 Class III studies in ALS. Important treatments are available for patients with ALS that are underutilized. Noninvasive ventilation (NIV), percutaneous endoscopic gastrostomy (PEG), and riluzole are particularly important and have the best evidence. More studies are needed to examine the best tests of respiratory function in ALS, as well as the optimal time for starting PEG, the impact of PEG on quality of life and survival, and the effect of vitamins and supplements on ALS. RECOMMENDATIONS: Riluzole should be offered to slow disease progression (Level A). PEG should be considered to stabilize weight and to prolong survival in patients with ALS (Level B). NIV should be considered to treat respiratory insufficiency in order to lengthen survival (Level B) and to slow the decline of forced vital capacity (Level B). NIV may be considered to improve quality of life (Level C) [corrected].Early initiation of NIV may increase compliance (Level C), and insufflation/exsufflation may be considered to help clear secretions (Level C).

Practice parameter update: the care of the patient with amyotrophic lateral sclerosis: multidisciplinary care, symptom management, and cognitive/behavioral impairment (an evidence-based review): report of the Quality Standards Subcommittee of the American Academy of Neurology.

OBJECTIVE: To systematically review evidence bearing on the management of patients with amyotrophic lateral sclerosis (ALS). METHODS: The authors analyzed studies from 1998 to 2007 to update the 1999 practice parameter. Topics covered in this section include breaking the news, multidisciplinary clinics, symptom management, cognitive and behavioral impairment, communication, and palliative care for patients with ALS. RESULTS: The authors identified 2 Class I studies, 8 Class II studies, and 30 Class III studies in ALS, but many important areas have been little studied. More high-quality, controlled studies of symptomatic therapies and palliative care are needed to guide management and assess outcomes in patients with ALS. RECOMMENDATIONS: Multidisciplinary clinic referral should be considered for managing patients with ALS to optimize health care delivery and prolong survival (Level B) and may be considered to enhance quality of life (Level C). For the treatment of refractory sialorrhea, botulinum toxin B should be considered (Level B) and low-dose radiation therapy to the salivary glands may be considered (Level C). For treatment of pseudobulbar affect, dextromethorphan and quinidine should be considered if approved by the US Food and Drug Administration (Level B). For patients who develop fatigue while taking riluzole, withholding the drug may be considered (Level C). Because many patients with ALS demonstrate cognitive impairment, which in some cases meets criteria for dementia, screening for cognitive and behavioral impairment should be considered in patients with ALS (Level B). Other management strategies all lack strong evidence.

Practice parameter: the evaluation of distal symmetric polyneuropathy: the role of laboratory and genetic testing (an evidence-based review). Report of the American Academy of Neurology, the American Association of Neuromuscular and Electrodiagnostic Medicine, and the American Academy of Physical Medicine and Rehabilitation.

BACKGROUND: Distal symmetric polyneuropathy (DSP) is the most common variety of neuropathy. Since the evaluation of this disorder is not standardized, the available literature was reviewed to provide evidence-based guidelines regarding the role of laboratory and genetic tests for the assessment of DSP. METHODS: A literature review using MEDLINE, EMBASE, Science Citation Index and Current Contents was performed to identify the best evidence regarding the evaluation of polyneuropathy published between 1980 and March 2007. Articles were classified according to a four-tiered level of evidence scheme and recommendations were based upon the level of evidence. RESULTS AND CONCLUSIONS: 1. Screening laboratory tests may be considered for all patients with polyneuropathy (Level C). Those tests that provide the highest yield of abnormality are blood glucose, serum B12 with metabolites (methylmalonic acid with or without homocysteine) and serum protein immunofixation electrophoresis (Level C). If there is no definite evidence of diabetes mellitus by routine testing of blood glucose, testing for impaired glucose tolerance may be considered in distal symmetric sensory polyneuropathy (Level C). 2. Genetic testing is established as useful for the accurate diagnosis and classification of hereditary neuropathies (Level A). Genetic testing may be considered in patients with cryptogenic polyneuropathy who exhibit a hereditary neuropathy phenotype (Level C). Initial genetic testing should be guided by the clinical phenotype, inheritance pattern, and electrodiagnostic (EDX) features and should focus on the most common abnormalities which are CMT1A duplication/HNPP deletion, Cx32 (GJB1), and MFN2 mutation screening. There is insufficient evidence to determine the usefulness of routine genetic testing in patients with cryptogenic polyneuropathy who do not exhibit a hereditary neuropathy phenotype (Level U).

Practice parameter: the evaluation of distal symmetric polyneuropathy: the role of autonomic testing, nerve biopsy, and skin biopsy (an evidence-based review). Report of the American Academy of Neurology, the American Association of Neuromuscular and Electrodiagnostic Medicine, and the American Academy of Physical Medicine and Rehabilitation.

BACKGROUND: Distal symmetric polyneuropathy (DSP) is the most common variety of neuropathy. Since the evaluation of this disorder is not standardized, the available literature was reviewed to provide evidence-based guidelines regarding the role of autonomic testing, nerve biopsy and skin biopsy for the assessment of polyneuropathy. METHODS: A literature review using MEDLINE, EMBASE, Science Citation Index and Current Contents was performed to identify the best evidence regarding the evaluation of polyneuropathy published between 1980 and March 2007. Articles were classified according to a four-tiered level of evidence scheme and recommendations were based upon the level of evidence. RESULTS AND CONCLUSIONS: 1. Autonomic testing may be considered in the evaluation of patients with polyneuropathy to document autonomic nervous system dysfunction (Level B). Such testing should be considered especially for the evaluation of suspected autonomic neuropathy (Level B) and distal small fiber sensory polyneuropathy (SFSN) (Level C). A battery of validated tests is recommended to achieve the highest diagnostic accuracy (Level B). 2. Nerve biopsy is generally accepted as useful in the evaluation of certain neuropathies as in patients with suspected amyloid neuropathy, mononeuropathy multiplex due to vasculitis, or with atypical forms of chronic inflammatory demyelinating polyneuropathy (CIDP). However, the literature is insufficient to provide a recommendation regarding when a nerve biopsy may be useful in the evaluation of DSP (Level U). 3. Skin biopsy is a validated technique for determining intraepidermal nerve fiber (IENF) density and may be considered for the diagnosis of DSP, particularly SFSN (Level C). There is a need for additional prospective studies to define more exact guidelines for the evaluation of polyneuropathy.

Adiposity and mortality in type 1 diabetes.

BACKGROUND: In the general population, adiposity exhibits a J- or U-shaped relationship with mortality; however, in catabolic states this relationship is often inversely linear. We have recently documented an age-independent increase in overweight/obesity in the Pittsburgh Epidemiology of Diabetes Complications Study (EDC) of type 1 diabetes (T1D). As intensified insulin therapy (IIT) may promote weight gain, the impact of weight gain in T1D is of importance. We therefore assessed the association of adiposity with mortality in 655 EDC participants during 20 years of follow-up. METHODS: Individuals were categorized as underweight (body mass index (BMI)<20), normal (20< or = BMI <25), overweight (25< or = BMI <30), or obese (BMI > or =30). Cox models were constructed using BMI and covariates at baseline, updated means during follow-up, time variation (reflecting most recent status), and change during adulthood as predictors of mortality. RESULTS: The prevalence of IIT (3+ insulin shots daily and/or pump) increased from 7 to 82%. Overweight increased by 47% and obesity increased sevenfold. There were 146 deaths. In unadjusted models, BMI (modeled continuously) showed a quadratic relationship with mortality (P=0.002, <0.0001 <0.0001 for baseline, updated mean and time-varying models, respectively). However, only in the time-varying model were the obese significantly different from the normal weight, whereas the baseline model showed no differences by BMI category. In both the updated mean and time-varying models, the underweight were at greater risk than were the normal weight (P<0.0001 both models). The nonlinear relationship of adiposity with mortality remained after adjustment for diabetes complications and for biological or socioeconomic/lifestyle risk factors, with the exception of baseline socioeconomic/lifestyle risk factors, in which a linear association emerged. Adjustment for waist circumference eliminated risk in the obese. Finally, weight gain during follow-up was protective. CONCLUSION: The relationship of adiposity with mortality in T1D now seems to resemble that of the general population, albeit with a marked increased risk in those who are underweight.

Aspergillus nidulans as a biological system to detect the genotoxic effects of mercury fumes on eukaryotes.

Mercury (Hg) pollution is one of the most serious environmental problems. Due to public concern prompted by the symptoms displayed by people who consumed contaminated fish in Minamata, Japan in 1956, Hg pollution has since been kept under constant surveillance. However, despite considerable accumulation of knowledge on the noxious effects of ingested or inhaled Hg, especially for humans, there is virtually nothing known about the genotoxic effects of Hg. Because increased mitotic crossing over is assumed to be the first step leading to carcinogenesis, we used a sensitive short-term test (homozygotization index) to look for DNA alterations induced by Hg fumes. In one Aspergillus nidulans diploid strain (UT448//UT184), the effects of the Hg fumes appeared scattered all over the DNA, causing 3.05 times more recombination frequencies than the mean for other strains. Another diploid (Dp II-I//UT184) was little affected by Hg. This led us to hypothesize that a genetic factor present in the UT184 master strain genome, close to the nicB8 genetic marker, is responsible for this behavior. These findings corroborate our previous findings that the homozygotization index can be used as a bioassay for rapid and efficient assessment of ecotoxicological hazards.

Evaluation of distal symmetric polyneuropathy: the role of laboratory and genetic testing (an evidence-based review).

Distal symmetric polyneuropathy (DSP) is the most common variety of neuropathy. Since the evaluation of this disorder is not standardized, the available literature was reviewed to provide evidence-based guidelines regarding the role of laboratory and genetic tests for the assessment of DSP. A literature review using MEDLINE, EMBASE, Science Citation Index, and Current Contents was performed to identify the best evidence regarding the evaluation of polyneuropathy published between 1980 and March 2007. Articles were classified according to a four-tiered level of evidence scheme and recommendations were based on the level of evidence. (1) Screening laboratory tests may be considered for all patients with polyneuropathy (Level C). Those tests that provide the highest yield of abnormality are blood glucose, serum B(12) with metabolites (methylmalonic acid with or without homocysteine), and serum protein immunofixation electrophoresis (Level C). If there is no definite evidence of diabetes mellitus by routine testing of blood glucose, testing for impaired glucose tolerance may be considered in distal symmetric sensory polyneuropathy (Level C). (2) Genetic testing is established as useful for the accurate diagnosis and classification of hereditary neuropathies (Level A). Genetic testing may be considered in patients with cryptogenic polyneuropathy who exhibit a hereditary neuropathy phenotype (Level C). Initial genetic testing should be guided by the clinical phenotype, inheritance pattern, and electrodiagnostic (EDX) features and should focus on the most common abnormalities, which are CMT1A duplication/HNPP deletion, Cx32 (GJB1), and MFN2 mutation screening. There is insufficient evidence to determine the usefulness of routine genetic testing in patients with cryptogenic polyneuropathy who do not exhibit a hereditary neuropathy phenotype (Level U).

Evaluation of distal symmetric polyneuropathy: the role of autonomic testing, nerve biopsy, and skin biopsy (an evidence-based review).

Distal symmetric polyneuropathy (DSP) is the most common variety of neuropathy. Since the evaluation of this disorder is not standardized, the available literature was reviewed to provide evidence-based guidelines regarding the role of autonomic testing, nerve biopsy, and skin biopsy for the assessment of polyneuropathy. A literature review using MEDLINE, EMBASE, Science Citation Index, and Current Contents was performed to identify the best evidence regarding the evaluation of polyneuropathy published between 1980 and March 2007. Articles were classified according to a four-tiered level of evidence scheme and recommendations were based on the level of evidence. (1) Autonomic testing may be considered in the evaluation of patients with polyneuropathy to document autonomic nervous system dysfunction (Level B). Such testing should be considered especially for the evaluation of suspected autonomic neuropathy (Level B) and distal small fiber sensory polyneuropathy (SFSN) (Level C). A battery of validated tests is recommended to achieve the highest diagnostic accuracy (Level B). (2) Nerve biopsy is generally accepted as useful in the evaluation of certain neuropathies as in patients with suspected amyloid neuropathy, mononeuropathy multiplex due to vasculitis, or with atypical forms of chronic inflammatory demyelinating polyneuropathy (CIDP). However, the literature is insufficient to provide a recommendation regarding when a nerve biopsy may be useful in the evaluation of DSP (Level U). (3) Skin biopsy is a validated technique for determining intraepidermal nerve fiber (IENF) density and may be considered for the diagnosis of DSP, particularly SFSN (Level C). There is a need for additional prospective studies to define more exact guidelines for the evaluation of polyneuropathy.

Practice Parameter: evaluation of distal symmetric polyneuropathy: role of laboratory and genetic testing (an evidence-based review). Report of the American Academy of Neurology, American Association of Neuromuscular and Electrodiagnostic Medicine, and American Academy of Physical Medicine and Rehabilitation.

BACKGROUND: Distal symmetric polyneuropathy (DSP) is the most common variety of neuropathy. Since the evaluation of this disorder is not standardized, the available literature was reviewed to provide evidence-based guidelines regarding the role of laboratory and genetic tests for the assessment of DSP. METHODS: A literature review using MEDLINE, EMBASE, and Current Contents was performed to identify the best evidence regarding the evaluation of polyneuropathy published between 1980 and March 2007. Articles were classified according to a four-tiered level of evidence scheme and recommendations were based upon the level of evidence. RESULTS AND RECOMMENDATIONS: 1) Screening laboratory tests may be considered for all patients with polyneuropathy (Level C). Those tests that provide the highest yield of abnormality are blood glucose, serum B12 with metabolites (methylmalonic acid with or without homocysteine), and serum protein immunofixation electrophoresis (Level C). If there is no definite evidence of diabetes mellitus by routine testing of blood glucose, testing for impaired glucose tolerance may be considered in distal symmetric sensory polyneuropathy (Level C). 2) Genetic testing should be conducted for the accurate diagnosis and classification of hereditary neuropathies (Level A). Genetic testing may be considered in patients with cryptogenic polyneuropathy who exhibit a hereditary neuropathy phenotype (Level C). Initial genetic testing should be guided by the clinical phenotype, inheritance pattern, and electrodiagnostic features and should focus on the most common abnormalities which are CMT1A duplication/HNPP deletion, Cx32 (GJB1), and MFN2 mutation screening. There is insufficient evidence to determine the usefulness of routine genetic testing in patients with cryptogenic polyneuropathy who do not exhibit a hereditary neuropathy phenotype (Level U).

Practice Parameter: evaluation of distal symmetric polyneuropathy: role of autonomic testing, nerve biopsy, and skin biopsy (an evidence-based review). Report of the American Academy of Neurology, American Association of Neuromuscular and Electrodiagnostic Medicine, and American Academy of Physical Medicine and Rehabilitation.

BACKGROUND: Distal symmetric polyneuropathy (DSP) is the most common variety of neuropathy. Since the evaluation of this disorder is not standardized, the available literature was reviewed to provide evidence-based guidelines regarding the role of autonomic testing, nerve biopsy, and skin biopsy for the assessment of polyneuropathy. METHODS: A literature review using MEDLINE, EMBASE, and Current Contents was performed to identify the best evidence regarding the evaluation of polyneuropathy published between 1980 and March 2007. Articles were classified according to a four-tiered level of evidence scheme and recommendations were based upon the level of evidence. RESULTS AND RECOMMENDATIONS: 1) Autonomic testing should be considered in the evaluation of patients with polyneuropathy to document autonomic nervous system dysfunction (Level B). Such testing should be considered especially for the evaluation of suspected autonomic neuropathy (Level B) and distal small fiber sensory polyneuropathy (SFSN) (Level C). A battery of validated tests is recommended to achieve the highest diagnostic accuracy (Level B). 2) Nerve biopsy is generally accepted as useful in the evaluation of certain neuropathies as in patients with suspected amyloid neuropathy, mononeuropathy multiplex due to vasculitis, or with atypical forms of chronic inflammatory demyelinating polyneuropathy (CIDP). However, the literature is insufficient to provide a recommendation regarding when a nerve biopsy may be useful in the evaluation of DSP (Level U). 3) Skin biopsy is a validated technique for determining intraepidermal nerve fiber density and may be considered for the diagnosis of DSP, particularly SFSN (Level C). There is a need for additional prospective studies to define more exact guidelines for the evaluation of polyneuropathy.

Changes in glycaemic control and risk of coronary artery disease in type 1 diabetes mellitus: findings from the Pittsburgh Epidemiology of Diabetes Complications Study (EDC).

AIMS/HYPOTHESIS: To complete a comparative analysis of studies that have examined the relationship between glycaemia and cardiovascular disease (CVD)/coronary artery disease (CAD) and perform a prospective analysis of the effect of change in glycosylated Hb level on CAD risk in the Pittsburgh Epidemiology of Diabetes Complications Study (EDC) of childhood-onset type 1 diabetes mellitus (n = 469) over 16 years of two yearly follow-up. METHODS: Measured values for HbA(1) and HbA(1c) from the EDC were converted to the DCCT-standard HbA(1c) for change analyses and the change in HbA(1c) was calculated (final HbA(1c) minus baseline HbA(1c)). CAD was defined as EDC-diagnosed angina, myocardial infarction, ischaemia, revascularisation or fatal CAD after medical record review. RESULTS: The comparative analysis suggested that glycaemia may have a stronger effect on CAD in patients without, than in those with, albuminuria. In EDC, the change in HbA(1c) differed significantly between CAD cases (+0.62 +/- 1.8%) and non-cases (-0.09 +/- 1.9%) and was an independent predictor of CAD. CONCLUSIONS/INTERPRETATION: Discrepant study results regarding the relationship of glycaemia with CVD/CAD may, in part, be related to the prevalence of renal disease. Measures of HbA(1c) change over time show a stronger association with CAD than baseline values.

Riluzole for amyotrophic lateral sclerosis (ALS)/motor neuron disease (MND).

BACKGROUND: Riluzole has been approved for treatment of patients with amyotrophic lateral sclerosis in most countries. Questions persist about its clinical utility because of high cost and modest efficacy. OBJECTIVES: To examine the efficacy of riluzole in prolonging survival, and in delaying the use of surrogates (tracheostomy and mechanical ventilation) to sustain survival. SEARCH STRATEGY: We searched the Cochrane Neuromuscular Disease Group Register for randomized trials in December 2004 and made enquiries of authors of trials, Aventis (manufacturer of riluzole) and other experts in the field. We searched MEDLINE (January 1966 to August 25 2006) and EMBASE (January 1980 to September 30th 2006). SELECTION CRITERIA: Types of studies: randomized trials. TYPES OF PARTICIPANTS: adults with a diagnosis of amyotrophic lateral sclerosis. Types of interventions: treatment with riluzole or placebo. Types of outcome measures: Primary: pooled hazard ratio of tracheostomy-free survival over all time points with riluzole 100 mg. Secondary: per cent mortality with riluzole 50, 100 and 200 mg; neurologic function, muscle strength and adverse events. DATA COLLECTION AND ANALYSIS: We identified four eligible randomized trials. MAIN RESULTS: The four trials examining tracheostomy-free survival included a total of 974 riluzole treated patients and 503 placebo treated patients. The methodological quality was acceptable and three trials were easily comparable, although one trial included older patients in more advanced stages of amyotrophic lateral sclerosis and one had multiple primary endpoints. Riluzole 100 mg per day provided a benefit for the homogeneous group of patients in the first two trials (P value = 0.042, hazard ratio 0.80, 95% confidence interval 0.64 to 0.99) and there was no evidence of heterogeneity (P value = 0.33). When the third trial (which included older and more seriously affected patients) was added, there was evidence of heterogeneity (P value < 0.0001) and the random effects model, which takes this into account, resulted in the overall treatment effect estimate falling just short of significance (P value = 0.056, hazard ratio 0.84, 95% confidence interval 0.70 to 1.01). This represented a 9% gain in the probability of surviving one year (57% in the placebo and 66% in the riluzole group). There was a small beneficial effect on both bulbar and limb function, but not on muscle strength. A threefold increase in serum alanine transferase was more frequent in riluzole treated patients than controls (weighted mean difference 2.62, 95% confidence interval 1.59 to 4.31). AUTHORS' CONCLUSIONS: Riluzole 100 mg daily is reasonably safe and probably prolongs median survival by about two to three months in patients with amyotrophic lateral sclerosis.