Executive Dysfunction in MCI: Subtype or Early Symptom

Mild cognitive impairment (MCI) may take several forms, and amnestic MCI (aMCI) has been recognized as an early stage of Alzheimer's Disease (AD). Impairment in executive functions including attention (eMCI) may be indicative of several neurodegenerative conditions. Executive impairment is frequently found in aMCI, it is significant for prognosis, and patients with eMCI may go on to develop AD. Recent studies have found changes in white matter integrity in patients with eMCI to be more sensitive than measures of cortical atrophy. Studies of genetic high-risk groups using sensitive cognitive neuroscience paradigms indicate that changes in executive function may be a cognitive marker useful for tracking development in an AD pathophysiological process

Self-reported cognitive and psychiatric symptoms at 3 months predict single-item measures of fatigue and daytime sleep 12 months after ischemic stroke

Introduction: Post-stroke fatigue and increased need for daytime sleep are multidimensional and insufficiently understood sequelae. Our aim was to study the relationships of self-reported cognitive and psychiatric symptoms at 3 months with fatigue and daytime sleep at 12 months post-stroke. Methods: Ischemic stroke patients without reported history of dementia or depression completed postal surveys 3- and 12-months post-stroke. At 3 months, psychiatric symptoms were assessed with the Hospital Anxiety and Depression Scale (HADS), and self-reported changes in cognitive symptoms (concentration and memory) compared to pre-stroke were assessed using single-item measures. At 12 months, single-item questions about changes in self-reported difficulties sleeping at night, fatigue and daytime sleep were included. First, we studied whether self-reported cognitive and/or psychiatric symptoms at 3 months were associated with daytime sleep and fatigue at 12 months using multiple logistic regression. Second, we fitted 2 structural equation models (SEMs) predicting fatigue and 2 models predicting daytime sleep. We compared a model where only age, sex, stroke severity (National Institutes of Health Stroke Scale; NIHSS), and difficulties sleeping at night predicted fatigue and daytime sleep at 12 months to a model where mental distress (i.e., a latent variable built of cognitive and psychiatric symptoms) was included as an additional predictor of fatigue and daytime sleep at 12 months. Results: Of 156 patients (NIHSS within 24 hours after admission (mean ± SD) = 3.6 ± 4.3, age = 73.0 ± 10.8, 41% female) 37.9% reported increased daytime sleep and 50.0% fatigue at 12 months. Increased psychiatric symptoms and worsened cognitive symptoms were associated with fatigue and daytime sleep at 12 months, after controlling for NIHSS, age, sex, and difficulties sleeping at night. SEM models including mental distress as predictor showed adequate model fit across 3 fit measures (highest RMSEA = 0.063, lowest CFI and TLI, both 0.975). Models without mental distress were not supported. Conclusion: Self-reported cognitive and psychiatric symptoms at 3 months predict increased daytime sleep and fatigue at 12 months. This highlights the relevance of monitoring cognitive and psychiatric symptoms in the subacute phase post-stroke. However, future research using validated measures of self-reported symptoms are needed to further explore these relationships.publishedVersio

Lesion topography and microscopic white matter tract damage contribute to cognitive impairment in symptomatic carotid artery disease

Purpose: To investigate associations between neuroimaging markers of cerebrovascular disease, including lesion topography and extent and severity of strategic and global cerebral tissue injury, and cognition in carotid artery disease (CAD). Materials and Methods: All participants gave written informed consent to undergo brain magnetic resonance imaging and the Addenbrooke’s Cognitive Examination–Revised. One hundred eight patients with symptomatic CAD but no dementia were included, and a score less than 82 represented cognitive impairment. Group comparison and interrelations between global cognitive and fluency performance, lesion topography, and ultrastructural damage were assessed with voxel-based statistics. Associations between cognition, medial temporal lobe atrophy (MTA), lesion volumes, and global white matter ultrastructural damage indexed as increased mean diffusivity were tested with regression analysis by controlling for age. Diagnostic accuracy of imaging markers selected from a multivariate prediction model was tested with receiver operating characteristic analysis. Results: Cognitively impaired patients (n = 53 [49.1%], classified as having probable vascular cognitive disorder) were older than nonimpaired patients (P = .027) and had more frequent MTA (P<.001), more cortical infarctions (P = .016), and larger volumes of acute (P = .028) and chronic (P = .009) subcortical ischemic lesions. Lesion volumes did not correlate with global cognitive performance (lacunar infarctions, P = .060; acute lesions, P = .088; chronic subcortical ischemic lesions, P = .085). In contrast, cognitive performance correlated with presence of chronic ischemic lesions within the interhemispheric tracts and thalamic radiation (P< .05, false discovery rate corrected). Skeleton mean diffusivity showed the closest correlation with cognition (R2 = 0.311, P< .001) and promising diagnostic accuracy for vascular cognitive disorder (area under the curve, 0.82 [95% confidence interval: 0.75, 0.90]). Findings were confirmed in subjects with a low risk of preclinical Alzheimer disease indexed by the absence of MTA (n = 85). Conclusion: Subcortical white matter ischemic lesion locations and severity of ultrastructural tract damage contribute to cognitive impairment in symptomatic CAD, which suggests that subcortical disconnection within large-scale cognitive neural networks is a key mechanism of vascular cognitive disorder

Imaging and neuropsychological correlates of white matter lesions in different subtypes of Mild Cognitive Impairment: A systematic review

BACKGROUND:White matter lesions (WML) are prevalent in older adults. The association between WML and cognition in different subtypes of Mild Cognitive Impairment (MCI) is inconsistent in the literature.OBJECTVES:We aim to provide a systematic review on the impact of WML in different subtypes of MCI, and discuss the recent findings on white matter plasticity.METHODS:We reviewed peer-reviewed articles from January 2011 to August 2016 and identified 12 studies investigating the association between WML and subtypes of MCI with both neuroimaging and cognitive measures.RESULTS:Our review shows that 1) WM abnormality was identified between different subtypes of MCI and healthy controls on diffusion imaging; 2) neither visual ratings of WML nor its volumetry differentiate different subtypes of MCI or its prognosis to dementia; and 3) cognitive correlates of WML were evident in the Amnestic-type MCI in the domains of memory, language, psychomotor speed, attention and executive functions.CONCLUSION:Cognitive reserve and the plasticity of white matter may modulate the impact of WML on the manifestation of the neurodegenerative disease. Further research is needed to study the plasticity of white matter in the MCI population to evaluate its potential clinical application

La déduction en matière de taxe sur la valeur ajoutée : étude en droit franco-lituanien

La comparaison entre des systèmes civilistes et, plus particulièrement, la France et la Lituanie, permet de confronter des expériences diverses au service de la construction de l’Union européenne. La méthode comparatiste peut, dans une approche régulatrice, permettre de réaliser une véritable intégration commune pour une matière comme le droit fiscal et d’appréhender les modalités du droit à déduction de la TVA relatives à l’exercice régulier et abusif d’un tel droit. Depuis la création de la TVA, comme instrument majeur pour financer le budget des États, le moment est venu de porter un regard critique sur le système de la TVA. Le droit à déduction de la TVA est fondamental pour le système de la TVA et sa neutralité. La taxe sur la valeur ajoutée a une incidence considérable sur chaque citoyen de l'Union européenne et il faut se donner les moyens en vue d’améliorer le mécanisme d’application de la déduction et créer des méthodes supplémentaires de lutte contre la fraudeThe comparison between civil law systems and, more particularly, between France and Lithuania, allows to confront diverse experiences in favour of the European Union’s construction. The comparative method allows, in a regulating approach, to realize a real common integration of a subject like tax law and better understand the conditions of VAT deduction related to the deduction practise in the regular or abusive way. Since the establishment of VAT, as a major instrument to fund the State’s budget, it is the time to take a critical look on the VAT system. The right to deduct VAT is fundamental composant of VAT system and of its neutrality. The value added tax has a significant impact on each citizen of the European Union and we must give ourselves the means to improve the application of the deduction mechanism and develop the additional methods to fight against frau