White matter hyperintensities are a core feature of Alzheimer's disease: Evidence from the Dominantly Inherited Alzheimer Network
Objective. White matter hyperintensities(WMH) are areas of increased signal on magnetic resonance imaging(MRI) scans that most commonly reflect small vessel cerebrovascular disease. Increased WMH volume is associated with risk and progression of Alzheimer's disease(AD). These observations are typically interpreted as evidence that vascular abnormalities play an additive, independent role contributing to symptom presentation, but not core features of AD. We examined the severity and distribution of WMH in presymptomaticPSEN1, PSEN2, and APP mutation carriers to determine the extent to which WMH manifest in individuals genetically-determined to develop AD.
Methods. The study comprised participants(n=299, age=39.03±10.13) from the Dominantly Inherited Alzheimer Network, including 184(61.5%) with a mutation that results in AD and 115(38.5%) first-degree relatives who were non-carrier controls. We calculated the estimated years from expected symptom onset(EYO) by subtracting the affected parent's symptom onset age from the participant's age. Baseline MRI data were analyzed for total and regional WMH. Mixed effects piecewise linear regression was used to examine WMH differences between carriers and non-carriers with respect to EYO.
Results. Mutation carriers had greater total WMH volumes, which appeared to increase approximately 6 years prior to expected symptom onset. The effects were most prominent for the parietal and occipital lobe, which showed divergent effects as early as 22 years prior to estimated onset.
Interpretation. Autosomal dominant AD is associated with increased WMH well before expected symptom onset. The findings suggest the possibility that WMH are a core feature of AD, a potential therapeutic target, and a factor that should be integrated into pathogenic models of the disease.
Annals of Neurology 2016
Association of Antipsychotic Use With Mortality Risk in Patients With Parkinson Disease
Importance As many as 60% of patients with Parkinson disease (PD) experience psychosis, 80% develop dementia, and the use of antipsychotics (APs) in the population with PD is common. The use of APs by patients with dementia in the general population is associated with increased mortality, but whether this risk extends to patients with PD remains unknown.
Objective To determine whether AP use in patients with PD is associated with increased mortality.
Design, Setting, and Participants This retrospective matched-cohort study used data from a Veterans Health Administration database from fiscal years 1999 to 2010 to examine the risk associated with AP use in a cohort of patients with idiopathic PD and recent stable physical health. The rates of 180-day mortality were compared in 7877 patients initiating AP therapy and 7877 patients who did not initiate AP therapy (matched for age ±2.5 years, sex, race, index year, presence and duration of dementia, PD duration, delirium, hospitalization, Charlson Comorbidity Index, and new nonpsychiatric medications). Data were analyzed from October 19, 2012, to September 21, 2015.
Main Outcomes and Measures Mortality rates at 180 days in those patients who initiated AP therapy compared with matched patients who did not use APs. Cox proportional hazards regression models were used with intent-to-treat (ITT) and exposure-only analyses.
Results The study population included 7877 matched pairs of patients with PD (65 women [0.8%] and 7812 men [99.2%] in each cohort; mean [SD] age, 76.3 [7.7] years for those who initiated AP therapy and 76.4 [7.6] years for those who did not). Antipsychotic use was associated with more than twice the hazard ratio (HR) of death compared with nonuse (ITT HR, 2.35; 95% CI, 2.08-2.66; P < .001). The HR was significantly higher for patients who used typical vs atypical APs (ITT HR, 1.54; 95% CI, 1.24-1.91; P < .001). Among the atypical APs used, HRs relative to nonuse of APs in descending order were 2.79 (95% CI, 1.97-3.96) for olanzapine, 2.46 (95% CI, 1.94-3.12) for risperidone, and 2.16 (95% CI, 1.88-2.48) for quetiapine fumarate.
Conclusions and Relevance Use of APs is associated with a significantly increased mortality risk in patients with PD, after adjusting for measurable confounders. This finding highlights the need for cautious use of APs in patients with PD. Future studies should examine the role of nonpharmacologic strategies in managing psychosis in PD. In addition, new pharmacologic treatments that do not increase mortality in patients with neurodegenerative diseases need to be developed.
JAMA Neurology 2016
Exploring the Association Between Rosacea and Parkinson Disease A Danish Nationwide Cohort Study
Importance The pathogenesis of rosacea is unclear, but increased matrix metalloproteinase target tissue activity appears to play an important role. Parkinson disease and other neurodegenerative disorders also display increased matrix metalloproteinase activity that contribute to neuronal loss.
Objective To investigate the risk of incident (new-onset) Parkinson disease in patients with rosacea.
Design, Setting, and Participants A nationwide cohort study of the Danish population was conducted using individual-level linkage of administrative registers. All Danish citizens 18 years or older from January 1, 1997, to December 31, 2011 (N = 5 472 745), were included. Data analysis was conducted from June 26 to July 27, 2015.
Main Outcomes and Measures The main outcome was a diagnosis of Parkinson disease. Incidence rates (IRs) per 10 000 person-years were calculated, and incidence rate ratios (IRRs) adjusted for age, sex, socioeconomic status, smoking, alcohol abuse, medication, and comorbidity were estimated by Poisson regression models.
Results A total of 5 404 692 individuals were included in the reference population; of these, 22 387 individuals (9812 [43.8%] women; mean [SD] age at diagnosis, 75.9 [10.2] years) received a diagnosis of Parkinson disease during the study period and 68 053 individuals (45 712 [67.2%] women; mean age, 42.2 [16.5] years) were registered as having rosacea. The IRs of Parkinson disease per 10 000 person-years were 3.54 (95% CI, 3.49-3.59) in the reference population and 7.62 (95% CI, 6.78-8.57) in patients with rosacea. The adjusted IRR of Parkinson disease was 1.71 (95%, CI 1.52-1.92) in patients with rosacea compared with the reference population. There was a 2-fold increased risk of Parkinson disease in patients classified as having ocular rosacea (adjusted IRR, 2.03 [95% CI, 1.67-2.48]), and tetracycline therapy appeared to reduce the risk of Parkinson disease (adjusted IRR, 0.98 [95% CI, 0.97-0.99]).
Conclusions and Relevance Rosacea constitutes an independent risk factor for Parkinson disease. This association could be due to shared pathogenic mechanisms involving elevated matrix metalloproteinase activity. The clinical consequences of this association require further study.
JAMA Neurology 2016
Imaging Parameters and Recurrent Cerebrovascular Events in Patients With Minor Stroke or Transient Ischemic Attack
Importance Neurological worsening and recurrent stroke contribute substantially to morbidity associated with transient ischemic attacks and strokes (TIA-S).
Objective To determine predictors of early recurrent cerebrovascular events (RCVEs) among patients with TIA-S and National Institutes of Health Stroke Scale scores of 0 to 3.
Design, Setting, and Participants A retrospective cohort study was conducted at 2 tertiary care centers (Columbia University Medical Center, New York, New York, and Tulane University Medical Center, New Orleans, Louisiana) between January 1, 2010, and December 31, 2014. All patients with neurologist-diagnosed TIA-S with a National Institutes of Health Stroke Scale score of 0 to 3 who presented to the emergency department were included.
Main Outcomes and Measures The primary outcome (adjudicated by 3 vascular neurologists) was RCVE: neurological deterioration in the absence of a medical explanation or recurrent TIA-S during hospitalization.
Results Of the 1258 total patients, 1187 had no RCVEs and 71 had RCVEs; of this group, 750 patients (63.2%) and 39 patients (54.9%), respectively, were aged 60 years or older. There were 505 patients with TIA-S at Columbia University; 31 (6.1%) had RCVEs (15 patients had neurological deterioration only, 11 had recurrent TIA-S only, and 5 had both). The validation cohort at Tulane University consisted of 753 patients; 40 (5.3%) had RCVEs (24 patients had neurological deterioration only and 16 had both). Predictors of RCVE in multivariate models in both cohorts were infarct on neuroimaging (computed tomographic scan or diffusion-weighted imaging sequences on magnetic resonance imaging) (Columbia University: not applicable and Tulane University: odds ratio, 1.75; 95% CI, 0.82-3.74; P = .15) and large-vessel disease etiology (Columbia University: odds ratio, 6.69; 95% CI, 3.10-14.50 and Tulane University: odds ratio, 8.13; 95% CI, 3.86-17.12; P < .001). There was an increase in the percentage of patients with RCVEs when both predictors were present. When neither predictor was present, the rate of RCVE was extremely low (up to 2%). Patients with RCVEs were less likely to be discharged home in both cohorts.
Conclusions and Relevance In patients with minor stroke, vessel imaging and perhaps neuroimaging parameters, but not clinical scores, were associated with RCVEs in 2 independent data sets. Prospective studies are needed to validate these predictors.
JAMA Neurology 2016
Motor neuron degeneration in spastic paraplegia 11 mimics amyotrophic lateral sclerosis lesions
The most common form of autosomal recessive hereditary spastic paraplegia is caused by mutations in the SPG11/KIAA1840 gene on chromosome 15q. The nature of the vast majority of SPG11 mutations found to date suggests a loss-of-function mechanism of the encoded protein, spatacsin. The SPG11 phenotype is, in most cases, characterized by a progressive spasticity with neuropathy, cognitive impairment and a thin corpus callosum on brain MRI. Full neuropathological characterization has not been reported to date despite the description of >100 SPG11 mutations. We describe here the clinical and pathological features observed in two unrelated females, members of genetically ascertained SPG11 families originating from Belgium and Italy, respectively. We confirm the presence of lesions of motor tracts in medulla oblongata and spinal cord associated with other lesions of the central nervous system. Interestingly, we report for the first time pathological hallmarks of SPG11 in neurons that include intracytoplasmic granular lysosome-like structures mainly in supratentorial areas, and others in subtentorial areas that are partially reminiscent of those observed in amyotrophic lateral sclerosis, such as ubiquitin and p62 aggregates, except that they are never labelled with anti-TDP-43 or anti-cystatin C. The neuropathological overlap with amyotrophic lateral sclerosis, associated with some shared clinical manifestations, opens up new fields of investigation in the physiopathological continuum of motor neuron degeneration.
Lancet Neurology 2016
Neurological prognostication of outcome in patients in coma after cardiac arrest
Summary
Management of coma after cardiac arrest has improved during the past decade, allowing an increasing proportion of patients to survive, thus prognostication has become an integral part of post-resuscitation care. Neurologists are increasingly confronted with raised expectations of next of kin and the necessity to provide early predictions of long-term prognosis. During the past decade, as technology and clinical evidence have evolved, post-cardiac arrest prognostication has moved towards a multimodal paradigm combining clinical examination with additional methods, consisting of electrophysiology, blood biomarkers, and brain imaging, to optimise prognostic accuracy. Prognostication should never be based on a single indicator; although some variables have very low false positive rates for poor outcome, multimodal assessment provides resassurance about the reliability of a prognostic estimate by offering concordant evidence.
Lancet Neurology 2016
Deletions at 22q11.2 in idiopathic Parkinson's disease: a combined analysis of genome-wide association data
Background
Parkinson's disease has been reported in a small number of patients with chromosome 22q11.2 deletion syndrome. In this study, we screened a series of large, independent Parkinson's disease case-control studies for deletions at 22q11.2.
Methods
We used data on deletions spanning the 22q11.2 locus from four independent case-control Parkinson's disease studies (UK Wellcome Trust Case Control Consortium 2, Dutch Parkinson's Disease Genetics Consortium, US National Institute on Aging, and International Parkinson's Disease Genomics Consortium studies), which were independent of the original reports of chromosome 22q11.2 deletion syndrome. We did case-control association analysis to compare the proportion of 22q11.2 deletions found, using the Fisher's exact test for the independent case-control studies and the Mantel-Haenszel test for the meta-analyses. We retrieved clinical details of patients with Parkinson's disease who had 22q11.2 deletions from the medical records of these patients.
Findings
We included array-based copy number variation data from 9387 patients with Parkinson's disease and 13 863 controls. Eight patients with Parkinson's disease and none of the controls had 22q11.2 deletions (p=0·00082). In the 8451 patients for whom age at onset data were available, deletions at 22q11.2 were associated with Parkinson's disease age at onset (Mann-Whitney U test p=0·001). Age at onset of Parkinson's disease was lower in patients carrying a 22q11.2 deletion (median 37 years, 95% CI 32·0–55·5; mean 42·1 years [SD 11·9]) than in those who did not carry a deletion (median 61 years, 95% CI 60·5–61·0; mean 60·3 years [SD 12·8]). A 22q11.2 deletion was present in more patients with early-onset (p<0·0001) and late-onset Parkinson's disease (p=0·016) than in controls, and in more patients with early-onset than late-onset Parkinson's disease (p=0·005).
Interpretation
Clinicians should be alert to the possibility of 22q11.2 deletions in patients with Parkinson's disease who have early presentation or features associated with the chromosome 22q11.2 deletion syndrome, or both.
Lancet Neurology 2016
Mutations in Subunits of the Activating Signal Cointegrator 1 Complex Are Associated with Prenatal Spinal Muscular Atrophy and Congenital Bone Fractures.
Abstract
Clinical Implications of Neuroscience Research Intrinsic circuits of the striatum. Complexity and clinical correlations
The striatum is the input component of the basal ganglia circuits. It provides a hub for the interaction among multiple afferents and local intrastriatal networks that regulate basal ganglia function. Via their distinct cortical connections, different components of the striatum are key elements for control of different aspects of behavior: the nucleus accumbens is primarily involved in reward-based action learning, the caudate nucleus in goal-based action selection, and the putamen in habit formation and action sequencing.
Neurology 2016
Neurology 2016
Statins and risk of poststroke hemorrhagic complications
Objective: To assess whether statin treatment before or after acute ischemic stroke (AIS) affects the risk of acute intracerebral hemorrhage (ICH), postacute ICH, and mortality within 90 days.
Methods: Data were sought from the Virtual International Stroke Trials Archive, an international repository of clinical trials data. Using propensity score matching, we retrospectively compared patients with prior statin treatment and newly initiated statin within 3 days after AIS to patients without statin exposure. Outcomes of interest were acute symptomatic ICH (sICH), any acute ICH, postacute ICH, and mortality during follow-up of 3 months.
Results: A total of 8,535 patients (mean age 70 years, 54% male, median baseline NIH Stroke Scale score 13) were analyzed. After propensity score matching, prior statin use was not strongly associated with sICH (adjusted odds ratio [OR] 1.33, 95% confidence interval [CI] 0.83–2.14) or any ICH (adjusted OR 1.35, 95% CI 0.92–1.98). There was no evidence of an interaction between prior statin use and thrombolysis. New initiation of statins was not associated with postacute ICH (adjusted hazard ratio [HR] 1.60, 95% CI 0.70–3.65). There was a signal towards lower 90-day mortality in patients with prior statin use (adjusted HR 0.84, 95% CI 0.70–1.00) and especially early initiation of statins (adjusted HR 0.67, 95% CI 0.46–0.97).
Conclusions: Statin use prior to AIS was not associated with early hemorrhagic complications, irrespective of treatment with thrombolysis. New initiation of statin treatment early after AIS did not affect risk of postacute ICH, but might be associated with reduced mortality.
Neurology 2016
sabato 19 marzo 2016
Small fiber neuropathy: Getting bigger!
Etiological and clinical heterogeneity of small fiber neuropathy (SFN) precludes a unifying approach and necessitates reliance on recognizable clinical syndromes. Symptoms of SFN arise from dysfunction in nociception, temperature, and autonomic modalities. This review focuses on SFN involving nociception and temperature, examining epidemiology, etiology, clinical presentation, diagnosis, pathophysiology, and management. Prevalence of SFN is 52.95 per 100,000 population, and diabetes and idiopathic are the most common etiologies. Dysesthesia, allodynia, pain, burning, and coldness sensations frequently present in a length-dependent pattern. Additional autonomic features in gastrointestinal, urinary, or cardiovascular systems are frequent but poorly objectified. SFN is diagnosed by intraepidermal nerve fiber density and quantitative sensory and autonomic tests in combination with normal nerve conduction. Pathophysiological understanding centers on sodium channel dysfunction, and genetic forms are beginning to be understood. Treatment is directed at the underlying etiology supported by symptomatic treatment using antidepressants and anticonvulsants. Little is known about long-term outcomes, and systematic cohort studies are needed.
Muscle Nerve, 2016
Reverse fiber type disproportion: A distinct metabolic myopathy
Introduction
In this investigation we characterized the physiological and metabolic responses to incremental exercise in 13 subjects with a predominance of type II fibers on muscle biopsy.
Methods
Subjects underwent incremental exercise testing with measures of maximum oxygen uptake ( 
O2 max), maximum heart rate (fc max), chronotropic index (fc/ 
O2 slope), maximum ventilation ( 
emax), blood lactate, ammonia, and creatine kinase (CK) levels. Muscle fiber type was determined by myosin ATPase histochemistry.
O2 max), maximum heart rate (fc max), chronotropic index (fc/ O2 slope), maximum ventilation ( emax), blood lactate, ammonia, and creatine kinase (CK) levels. Muscle fiber type was determined by myosin ATPase histochemistry.Results
Muscle biopsies showed more type II fibers (75%) in subjects compared with normal individuals (P < 0.01). Subjects exhibited normal 
O2max and end-exercise lactate, whereas ammonia and CK levels at maximum exercise were significantly higher.
O2max and end-exercise lactate, whereas ammonia and CK levels at maximum exercise were significantly higher.Conclusions
Subjects with type II muscle fiber predominance exhibited exaggerated increases in ammonia and elevated CK levels during exercise. Predominance of type II fibers on muscle biopsy is the opposite finding of congenital fiber type disproportion; we suggest these patients be referred to as having “reverse fiber type disproportion.”
Muscle Nerve, 2016
The semiology of psychogenic nonepileptic seizures revisited: Can video alone predict the diagnosis? Preliminary data from a prospective feasibility study
Objective
To investigate if, when, and to what extent visual information contained in a video-recorded event allows experienced epileptologists to predict the diagnosis of psychogenic nonepileptic seizures (PNES) without the aid of electroencephalography (EEG).
Methods
Five neurologists actively practicing in epilepsy centers in Italy and the United States were asked to review 23 videos capturing representative events of 21 unselected consecutive patients admitted for long-term video-EEG monitoring (VEM). Four raters were blind to EEG and clinical information; one rater was not. They were requested to (1) rate the videos for quality and content; (2) choose among four diagnoses: (a) epileptic seizures (ES); (b) PNES; (c) Other nonepileptic seizures (NES; (syncope, movement disorder, migraine, etc.); (d) “Cannot Say”; and (3) explain in their own words the main reasons leading to the diagnosis of choice.
Results
All raters predicted the diagnosis correctly in 7 of 23 videos (all ES or PNES) (30.4%), whereas all raters failed in 5 of 23 cases (three Other NES, one PNES, one Cannot Say) (21.7%). The conditions that facilitate, and those that interfere with, a confident diagnosis were predictable. Degree of accuracy among raters was not uniform and was consistently better in three raters. Two among the four blind raters were as accurate as the rater who was not blinded. Interrater agreement was “moderate” (k = 0.52) for the overall group; “moderate” for ES (k = 0.53); “substantial” for PNES (k = 0.63); “fair” for Other NES (k = 0.21)—similar to the results obtained in a previous study evaluating the reliability of combined video-EEG.
Significance
In about one third of cases, a confident diagnosis of PNES/ES can be established on clinical grounds based on video data alone. Our results benefit all affected patients, particularly those with no access to video-EEG monitoring units.
Epilepsia 2016
A Placebo-Controlled Trial of AQW051 in Patients With Moderate to Severe Levodopa-Induced Dyskinesia
This phase 2 randomized, double-blind, placebo-controlled study evaluated the efficacy and safety of the nicotinic acetylcholine receptor α7 agonist AQW051 in patients with Parkinson's disease and levodopa-induced dyskinesia.
Methods
Patients with idiopathic Parkinson's disease and moderate to severe levodopa-induced dyskinesia were randomized to AQW051 10 mg (n = 24), AQW051 50 mg (n = 24), or placebo (n = 23) once daily for 28 days. Coprimary end points were change in Modified Abnormal Involuntary Movement Scale and Unified Parkinson's Disease Rating Scale part III scores. Secondary outcomes included pharmacokinetics.
Results
In total, 67 patients completed the study. AQW051-treated patients experienced no significant improvements in Modified Abnormal Involuntary Movement Scale or Unified Parkinson's Disease Rating Scale part III scores by day 28. AQW051 was well tolerated; the most common adverse events were dyskinesia, fatigue, nausea, and falls.
Conclusions
AQW051 did not significantly reduce dyskinesia or parkinsonian severity.
Movement Disorders 2016
EMA reviewing gadolinium contrast agents used in MRI scans
Review to consider evidence on gadolinium accumulation in brain tissue
The European Medicines Agency (EMA) has started a review of the risk of gadolinium deposition in brain tissue following the use of gadolinium contrast agents in patients having magnetic resonance imaging (MRI) scans.
Gadolinium contrast agents are diagnostic products that may be given to patients before or during MRI scans to help doctors obtain better images of organs and tissues. After administration, gadolinium agents are mostly eliminated via the kidneys but studies indicate that deposits can build up in some body tissues, including in the liver, kidney, muscle, skin and bone.
Recently, a number of publications have reported that gadolinium contrast agents also accumulate in brain tissue1-7. In January 2016, EMA’s Pharmacovigilance Risk Assessment Committee (PRAC) reviewed these publications. Although no adverse effects relating to gadolinium brain deposition have been reported to date, the PRAC will carry out an in-depth review of the risk of brain deposits and of the overall safety of these products.
The PRAC’s recommendations will be sent to Committee for Medicinal Products for Human Use (CHMP), which will issue the Agency’s final opinion.