Neurological disorders throughout acute SARS-CoV2 infection: A comparative study between vaccinated and non-vaccinated patients.

BACKGROUND: The role of vaccination on Covid-19 severity in neurological patients is still unknown. We aim at describing clinical characteristics and outcomes of breakthrough and unvaccinated Covid-19 patients hospitalized for neurological disorders. METHODS: Two hundred thirty-two Covid-19 patients were admitted to a neuro-Covid Unit form March 1st 2021 to February 28th 2022. Out of the total sample, 74 (32%) were full vaccinated. The prevalence, clinical characteristics, disease severity, expressed by Brescia-COVID Respiratory Severity Scale (BCRSS) and National Early Warning Score 2 (NEWS2), and final outcomes of neurological syndromes were compared between vaccinated and unvaccinated cases. Cox regression analysis was implemented in order to investigate the combined effect of predictors of mortality. RESULTS: Breakthrough vaccinated cases were older (years 72.4 ± 16.3 vs 67.0 ± 18.9 years, p = 0.029), showed higher pre-admission comorbidity score and Clinical Frailty scale score (4.46 ± 1.6 vs 3.75 ± 2.0, p = 0.008) with no differences in terms of disease progression or mortality rate (16.2% vs 15.2%), compared to full-dose vaccinated patients. Cox-regression analysis showed age and NEWS2 score as the variables with a significant relation to mortality between the two groups, independently from pre-morbid conditions and inflammatory response. CONCLUSION: This study on breakthrough COVID-19 infection could help identify vulnerable neurological patients with higher risk of poor outcomes.

Incidence and Long-term Functional Outcome of Neurologic Disorders in Hospitalized Patients With COVID-19 Infected With Pre-Omicron Variants.

BACKGROUND AND OBJECTIVES: A variety of neurologic disorders have been reported as presentations or complications of coronavirus disease 2019 (COVID-19) infection. The objective of this study was to determine their incidence dynamics and long-term functional outcome. METHODS: The Neuro-COVID Italy study was a multicenter, observational, cohort study with ambispective recruitment and prospective follow-up. Consecutive hospitalized patients presenting new neurologic disorders associated with COVID-19 infection (neuro-COVID), independently from respiratory severity, were systematically screened and actively recruited by neurology specialists in 38 centers in Italy and the Republic of San Marino. The primary outcomes were incidence of neuro-COVID cases during the first 70 weeks of the pandemic (March 2020-June 2021) and long-term functional outcome at 6 months, categorized as full recovery, mild symptoms, disabling symptoms, or death. RESULTS: Among 52,759 hospitalized patients with COVID-19, 1,865 patients presenting 2,881 new neurologic disorders associated with COVID-19 infection (neuro-COVID) were recruited. The incidence of neuro-COVID cases significantly declined over time, comparing the first 3 pandemic waves (8.4%, 95% CI 7.9-8.9; 5.0%, 95% CI 4.7-5.3; 3.3%, 95% CI 3.0-3.6, respectively; p = 0.027). The most frequent neurologic disorders were acute encephalopathy (25.2%), hyposmia-hypogeusia (20.2%), acute ischemic stroke (18.4%), and cognitive impairment (13.7%). The onset of neurologic disorders was more common in the prodromic phase (44.3%) or during the acute respiratory illness (40.9%), except for cognitive impairment whose onset prevailed during recovery (48.4%). A good functional outcome was achieved by most patients with neuro-COVID (64.6%) during follow-up (median 6.7 months), and the proportion of good outcome increased throughout the study period (r = 0.29, 95% CI 0.05-0.50; p = 0.019). Mild residual symptoms were frequently reported (28.1%) while disabling symptoms were common only in stroke survivors (47.6%). DISCUSSION: Incidence of COVID-associated neurologic disorders decreased during the prevaccination phase of the pandemic. Long-term functional outcome was favorable in most neuro-COVID disorders, although mild symptoms commonly lasted more than 6 months after infection.

Predictors of "brain fog" 1 year after COVID-19 disease.

INTRODUCTION: Brain fog has been described up to 1 year after SARS-CoV-2 infection, notwithstanding the underlying mechanisms are still poorly investigated. In this study, we aimed to evaluate the prevalence of cognitive complaints at 1-year follow-up and to identify the factors related to persistent brain fog in COVID-19 patients. METHODS: Out of 246 COVID patients, hospitalized from March 1st to May 31st, a sample of 137 patients accepted to be evaluated at 1 year from discharge, through a full clinical, neurological, and psychological examination, including the Montreal Cognitive Assessment (MoCA), impact of event scale-revised (IES-R), Zung self-rating depression scale (SDS), Zung self-rating anxiety scale (SAS), and fatigue severity scale (FSS). Subjects with prior cognitive impairment and/or psychiatric disorders were excluded. RESULTS: Patients with cognitive disorders exhibited lower MoCA score (22.9 ± 4.3 vs. 26.3 ± 3.1, p = 0.002) and higher IES-R score (33.7 ± 18.5 vs. 26.4 ± 16.3, p = 0.050), SDS score (40.9 ± 6.5 vs. 35.5 ± 8.6, p = 0.004), and fatigue severity scale score (33.6 ± 16.1 vs. 23.7 ± 12.5, p = 0.001), compared to patients without cognitive complaints. Logistic regression showed a significant correlation between brain fog and the self-rating depression scale values (p = 0.020), adjusted for age (p = 0.445), sex (p = 0.178), premorbid Cumulative Illness Rating Scale (CIRS) (p = 0.288), COVID-19 severity (BCRSS) (p = 0.964), education level (p = 0.784) and MoCA score (p = 0.909). CONCLUSIONS: Our study showed depression as the strongest predictor of persistent brain fog, adjusting for demographic and clinical variables. Wider longitudinal studies are warranted to better explain cognitive difficulties after COVID-19.

Neurological and Mental Health Symptoms Associated with Post-COVID-19 Disability in a Sample of Patients Discharged from a COVID-19 Ward: A Secondary Analysis.

Recent studies suggest that COVID-19 survivors may experience long-term health consequences: in particular, neurological and mental health symptoms might be associated with long-term negative outcomes. This study is a secondary analysis of a larger cohort study and aims to determine the extent to which neurological and mental health sequelae are associated with survivors' disability. Participants include COVID-19 survivors, with no pre-morbid brain conditions, who were discharged from the COVID-19 Unit of the ASST Spedali Civili Hospital between February and April 2020. At an average of 3.5 months after discharge, they were submitted to a neurological examination and completed the WHO Disability Assessment Schedule (WHODAS-12), the Hospital Anxiety and Depression Score, the Pittsburgh Sleep Quality Index and the Montreal Cognitive Assessment. Multivariable regression analysis was carried out to analyze variables that explain WHODAS-12 variation. In total, 83 patients (63 males, average age 66.9, 95% CI: 64.2-69.7) were enrolled; average WHODAS-12 was 13.2 (95% CI: 9.7-16.6). Cognitive dysfunction, anxiety, fatigue, and hyposmia/hypogeusia explained 28.8% of WHODAS-12 variation. These findings underline the importance and need for longitudinal follow-up assessments after recovery from COVID-19 and suggest the need for early rehabilitation of residual symptoms to enhance patients' functioning.

Clinical outcome of neurological patients with COVID-19: the impact of healthcare organization improvement between waves.

OBJECTIVE: The aim of this study is to evaluate the differences in clinical presentations and the impact of healthcare organization on outcomes of neurological COVID-19 patients admitted during the first and second pandemic waves. METHODS: In this single-center cohort study, we included all patients with SARS-CoV-2 infection admitted to a Neuro-COVID Unit. Demographic, clinical, and laboratory data were compared between patients admitted during the first and second waves of the COVID-19 pandemic. RESULTS: Two hundred twenty-three patients were included, of whom 112 and 111 were hospitalized during the first and second pandemic waves, respectively. Patients admitted during the second wave were younger and exhibited pulmonary COVID-19 severity, resulting in less oxygen support (n = 41, 36.9% vs n = 79, 70.5%, p < 0.001) and lower mortality rates (14.4% vs 31.3%, p = 0.004). The different healthcare strategies and early steroid treatment emerged as significant predictors of mortality independently from age, pre-morbid conditions and COVID-19 severity in Cox regression analyses. CONCLUSIONS: Differences in healthcare strategies during the second phase of the COVID-19 pandemic probably explain the differences in clinical outcomes independently of disease severity, underlying the importance of standardized early management of neurological patients with SARS-CoV-2 infection.

Neurological involvement associated with COVID-19 disease: a study on psychosocial factors.

BACKGROUND: Several people affected by COVID-19 experienced neurological manifestations, altered sleep quality, mood disorders, and disability following hospitalization for a long time. OBJECTIVE: To explore the impact of different neurological symptoms on sleep quality, mood, and disability in a consecutive series of patients previously hospitalized for COVID-19 disease. METHODS: We evaluated 83 patients with COVID-19 around 3 months after hospital discharge. They were divided into 3 groups according to their neurological involvement (i.e., mild, unspecific, or no neurological involvement). Socio-demographic, clinical data, disability level, emotional distress, and sleep quality were collected and compared between the three groups. RESULTS: We found that higher disability, depressive symptoms, and lower sleep quality in patients with mild neurological involvement compared to patients with unspecific and no neurological involvement. Differences between groups were also found for clinical variables related to COVID-19 severity. CONCLUSION: After 3 months from hospital discharge, patients with more severe COVID-19 and mild neurological involvement experienced more psychosocial alterations than patients with unspecific or no neurological involvement. Both COVID-19 and neurological manifestations' severity should be considered in the clinical settings to plain tailored interventions for patients recovering from COVID-19.

Premorbid vulnerability and disease severity impact on Long-COVID cognitive impairment.

BACKGROUND: Cognitive deficits have been increasingly reported as possible long-term manifestations after SARS-CoV-2 infection. AIMS: In this study we aimed at evaluating the factors associated with cognitive deficits 6 months after hospitalization for Coronavirus Disease 2019 (COVID-19). METHODS: One hundred and six patients, discharged from a pneumology COVID-19 unit between March 1 and May 30 2020, accepted to be evaluated at 6 months according to an extensive neurological protocol, including the Montreal Cognitive Assessment (MoCA). RESULTS: Abnormal MoCA scores at 6 months follow-up were associated with higher pre-hospitalization National Health System (NHS) score (Duca et al. in Emerg Med Pract 22:1-2, 2020) (OR 1.27; 95% CI 1.05-1.6; p = 0.029) and more severe pulmonary disease expressed by the Brescia-COVID Respiratory Severity Scale (Duca et al. in Emerg Med Pract 22:1-2, 2020) (BCRSS > 1OR 4.73; 95% CI 1.53-14.63; p = 0.003) during the acute phase of the disease. DISCUSSION: This longitudinal study showed that the severity of COVID-19, indicated by BCRSS, and a complex score given by age and premorbid medical conditions, expressed by NHS, play a major role in modulating the long-term cognitive consequences of COVID-19 disease. CONCLUSIONS: These findings indicate that the association of age and premorbid factors might identify people at risk for long-term neurological consequences of COVID-19 disease, thus deserving longer and proper follow-up.

Long-term neurological manifestations of COVID-19: prevalence and predictive factors.

BACKGROUND: Clinical investigations have argued for long-term neurological manifestations in both hospitalised and non-hospitalised COVID-19 patients. It is unclear whether long-term neurological symptoms and features depend on COVID-19 severity. METHODS: From a sample of 208 consecutive non-neurological patients hospitalised for COVID-19 disease, 165 survivors were re-assessed at 6 months according to a structured standardised clinical protocol. Prevalence and predictors of long-term neurological manifestations were evaluated using multivariate logistic regression analyses. RESULTS: At 6-month follow-up after hospitalisation due to COVID-19 disease, patients displayed a wide array of symptoms; fatigue (34%), memory/attention (31%) and sleep disorders (30%) were the most frequent. At neurological examination, 40% of patients exhibited neurological abnormalities, such as hyposmia (18.0%), cognitive deficits (17.5%), postural tremor (13.8%) and subtle motor/sensory deficits (7.6%). Older age, premorbid comorbidities and severity of COVID-19 were independent predictors of neurological manifestations in logistic regression analyses. CONCLUSIONS: Premorbid vulnerability and severity of SARS-CoV-2 infection impact on prevalence and severity of long-term neurological manifestations.

Alterations of frontal-temporal gray matter volume associate with clinical measures of older adults with COVID-19.

COVID-19, the infectious disease caused by the most recently discovered severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), has become a global pandemic. It dramatically affects people's health and daily life. Neurological complications are increasingly documented for patients with COVID-19. However, the effect of COVID-19 on the brain is less studied, and existing quantitative neuroimaging analyses of COVID-19 were mainly based on the univariate voxel-based morphometry analysis (VBM) that requires corrections for a large number of tests for statistical significance, multivariate approaches that can reduce the number of tests to be corrected have not been applied to study COVID-19 effect on the brain yet. In this study, we leveraged source-based morphometry (SBM) analysis, a multivariate extension of VBM, to identify changes derived from computed tomography scans in covarying gray matter volume patterns underlying COVID-19 in 120 neurological patients (including 58 cases with COVID-19 and 62 patients without COVID-19 matched for age, gender and diseases). SBM identified that lower gray matter volume (GMV) in superior/medial/middle frontal gyri was significantly associated with a higher level of disability (modified Rankin Scale) at both discharge and six months follow-up phases even when controlling for cerebrovascular diseases. GMV in superior/medial/middle frontal gyri was also significantly reduced in patients receiving oxygen therapy compared to patients not receiving oxygen therapy. Patients with fever presented significant GMV reduction in inferior/middle temporal gyri and fusiform gyrus compared to patients without fever. Patients with agitation showed GMV reduction in superior/medial/middle frontal gyri compared to patients without agitation. Patients with COVID-19 showed no significant GMV differences from patients without COVID-19 in any brain region. Results suggest that COVID-19 may affect the frontal-temporal network in a secondary manner through fever or lack of oxygen.

Clinical characteristics and outcomes of inpatients with neurologic disease and COVID-19 in Brescia, Lombardy, Italy.

OBJECTIVE: To report clinical and laboratory characteristics, treatment, and clinical outcomes of patients admitted for neurologic diseases with and without coronavirus disease 2019 (COVID-19). METHODS: In this retrospective, single-center cohort study, we included all adult inpatients with confirmed COVID-19 admitted to a neuro-COVID unit beginning February 21, 2020, who had been discharged or died by April 5, 2020. Demographic, clinical, treatment, and laboratory data were extracted from medical records and compared (false discovery rate corrected) to those of neurologic patients without COVID-19 admitted in the same period. RESULTS: One hundred seventy-three patients were included in this study, of whom 56 were positive and 117 were negative for COVID-19. Patients with COVID-19 were older (77.0 years, interquartile range [IQR] 67.0-83.8 years vs 70.1 years, IQR 52.9-78.6 years, p = 0.006), had a different distribution regarding admission diagnoses, including cerebrovascular disorders (n = 43, 76.8% vs n = 68, 58.1%), and had a higher quick Sequential Organ Failure Assessment (qSOFA) score on admission (0.9, IQR 0.7-1.1 vs 0.5, IQR 0.4-0.6, p = 0.006). In-hospital mortality rates (n = 21, 37.5% vs n = 5, 4.3%, p < 0.001) and incident delirium (n = 15, 26.8% vs n = 9, 7.7%, p = 0.003) were significantly higher in the COVID-19 group. Patients with COVID-19 and without COVID with stroke had similar baseline characteristics, but patients with COVID-19 had higher modified Rankin Scale scores at discharge (5.0, IQR 2.0-6.0 vs 2.0, IQR 1.0-3.0, p < 0.001), with a significantly lower number of patients with a good outcome (n = 11, 25.6% vs n = 48, 70.6%, p < 0.001). In patients with COVID-19, multivariable regressions showed increasing odds of in-hospital death associated with higher qSOFA scores (odds ratio [OR] 4.47, 95% confidence interval [CI] 1.21-16.5, p = 0.025), lower platelet count (OR 0.98, 95% CI 0.97-0.99, p = 0.005), and higher lactate dehydrogenase (OR 1.01, 95% CI 1.00-1.03, p = 0.009) on admission. CONCLUSIONS: Patients with COVID-19 admitted with neurologic disease, including stroke, have a significantly higher in-hospital mortality and incident delirium and higher disability than patients without COVID-19.

Expanding the role of education in frontotemporal dementia: a functional dynamic connectivity (the chronnectome) study.

In the present study, we aim at investigating whether education modulates dynamical properties of time-varying whole-brain network connectivity (the chronnectome) in frontotemporal dementia (FTD) at a given level of symptom severity. Dynamic connectivity parameters were evaluated in 128 patients with FTD using independent component analysis, sliding-time window correlation, and k-means approach to resting state-magnetic resonance imaging data. We evaluated the relationship between education, a proxy measure of cognitive reserve, and 4 indexes of metastate dynamic connectivity: (1) the number of distinct metastates a patient passes through, (2) the number of switches from one metastate to another, (3) the span of the realized metastates, and (4) the total distance traveled in the state space. We found a significant inverse correlation between years of education and the 4 indexes of metastate dynamic fluidity (all p-values ≤ 0.03, false discovery rate-corrected). This study suggests that patients with FTD with higher education but comparable clinical severity show more global functional brain impairment, suggesting that patients with higher cognitive reserve can cope with more global brain fluidity reduction.

Brain Connectivity and Information-Flow Breakdown Revealed by a Minimum Spanning Tree-Based Analysis of MRI Data in Behavioral Variant Frontotemporal Dementia.

Brain functional disruption and cognitive shortfalls as consequences of neurodegeneration are among the most investigated aspects in current clinical research. Traditionally, specific anatomical and behavioral traits have been associated with neurodegeneration, thus directly translatable in clinical terms. However, these qualitative traits, do not account for the extensive information flow breakdown within the functional brain network that deeply affect cognitive skills. Behavioural variant Frontotemporal Dementia (bvFTD) is a neurodegenerative disorder characterized by behavioral and executive functions disturbances. Deviations from the physiological cognitive functioning can be accurately inferred and modeled from functional connectivity alterations. Although the need for unbiased metrics is still an open issue in imaging studies, the graph-theory approach applied to neuroimaging techniques is becoming popular in the study of brain dysfunction. In this work, we assessed the global connectivity and topological alterations among brain regions in bvFTD patients using a minimum spanning tree (MST) based analysis of resting state functional MRI (rs-fMRI) data. Whilst several graph theoretical methods require arbitrary criteria (including the choice of network construction thresholds and weight normalization methods), MST is an unambiguous modeling solution, ensuring accuracy, robustness, and reproducibility. MST networks of 116 regions of interest (ROIs) were built on wavelet correlation matrices, extracted from 41 bvFTD patients and 39 healthy controls (HC). We observed a global fragmentation of the functional network backbone with severe disruption of information-flow highways. Frontotemporal areas were less compact, more isolated, and concentrated in less integrated structures, respect to healthy subjects. Our results reflected such complex breakdown of the frontal and temporal areas at both intra-regional and long-range connections. Our findings highlighted that MST, in conjunction with rs-fMRI data, was an effective method for quantifying and detecting functional brain network impairments, leading to characteristic bvFTD cognitive, social, and executive functions disorders.

Autoimmunity and Frontotemporal Dementia.

BACKGROUND: Frontotemporal Dementia (FTD) is a neurodegenerative disorder which asymmetrically affects the frontotemporal lobe, characterized by behavioural abnormalities, language impairment, and deficits of executive functions. Genetic studies identified mutations causing the disease, namely Microtubule Associated Protein Tau (MAPT), Granulin (GRN) and chromosome 9 open reading frame 72 (C9orf72) mutations, which contributed to elucidate the molecular pathways involved in brain depositions of either Tau or TAR DNA-binding protein 43 (TDP43) inclusions. However, in the majority of sporadic FTD patients, the mechanisms triggering Tau or TDP43 protein deposition are still to be uncovered. OBJECTIVE: We aimed to present an extensive evaluation of literature data on immune homeostasis in FTD, in order to provide potentially evidence-based approaches for a disease still orphan of any treatment. METHODS: A structured search of bibliographic databases from peer-reviewed literature was pursued focusing on autoimmunity in the brain and FTD. RESULTS: One-hundred-fourteen papers were included in this review. The majority of studies (32) were represented by extensive literature revision on immunity, central nervous system (CNS) and autoimmunity; neuroimaging papers (11) in autoimmune diseases were evaluated, and immunomodulatory approaches (25) were revised. Six papers were found specifically related to FTD and autoimmune hypothesis, the other papers referring to current state of art on FTD. CONCLUSION: Overall this review contribute to expand the knowledge of a possible immune hypothesis in FTD, suggesting therapeutic perspectives in autoimmune related neurodegeneration, to reduce or revert the disease.

Neuroanatomical Correlates of Transcranial Magnetic Stimulation in Presymptomatic Granulin Mutation Carriers.

Frontotemporal dementia (FTD) is characterized by behavioural and language impairment, accompanied by atrophic changes in fronto-temporo-insular cortices. In the presymptomatic phases of genetic FTD, subtle or no volumetric changes have been reported. Transcranial magnetic stimulation (TMS) represents an approach to explore cortical connectivity, and some TMS measures have been demonstrated to be impaired in Granulin (GRN) mutation carriers. We aimed at exploring cross-sectional changes in cortical thickness (CT) and surface area (SA) in the presymptomatic phases of GRN-related FTD, and their relationship with TMS parameters. Nineteen presymptomatic GRN mutation carriers and seventeen age and sex-matched non-carriers underwent 3T MRI scanning and a paired-pulse TMS protocol. The surface-based pipeline of FreeSurfer was applied in order to obtain cortical volumes (CVs), CT and SA measures. Then, between groups differences and correlation with TMS parameters were assessed. GRN carriers showed increased CT and decreased SA of the right parietal lobe, without significant volume changes. TMS parameters of intracortical inhibition and facilitation, which were significantly impaired in presymptomatic GRN mutation carriers, correlated with reduced SA and CV of the right insula. Our results suggest that splitting CV into its two main components could improve the sensitivity when exploring structural brain changes in presymptomatic or early phases of neurodegenerative conditions. TMS parameters might reflect damage within cortical regions reported to be affected early in the conversion to the symptomatic phase of the disease.

Natural history and predictors of survival in progressive supranuclear palsy.

BACKGROUND: Progressive supranuclear palsy is a neurodegenerative disorder characterized by high functional disability and rapidly progressive dependency. The predictors of survival are still unclear. METHODS: The predictors of survival were evaluated in a group of clinically diagnosed PSP patients, focusing primarily on extensive cognitive assessment. RESULTS: The mean survival time from symptom onset was 8.25±3.0years. Sex, age at onset, education, occupation and severity of extrapyramidal symptoms did not correlate with survival. The only factor associated with a shorter life expectancy in our cohort was the presence of dementia at diagnosis. Impairment of executive functions was the best predictor of an unfavorable outcome. CONCLUSIONS: Our findings suggest that dementia and executive functions need to be evaluated in order to define survival probability in PSP patients.

Mild Cognitive Impairment and Progression to Dementia in Progressive Supranuclear Palsy.

BACKGROUND: Cognitive deficits are common in progressive supranuclear palsy (PSP), but their relevance and the progression to dementia are still poorly described. The recently revised criteria for PSP consider cognitive dysfunction in the diagnostic work-up. METHODS: The study retrospectively evaluated a series of 99 PSP patients with Richardson syndrome (PSP-RS), subgrouped according to cognitive and behavioural performances into PSP with normal cognition (PSP-NC), PSP with mild cognitive impairment (PSP-MCI), and PSP with dementia (PSP-D). The progression to dementia at the 3-year follow-up was assessed. RESULTS: At baseline, 15.2% of patients were classified as PSP-NC, 43.4% as PSP-MCI, and 41.4% as PSP-D. During the 3-year follow-up, 21 out of 29 patients, previously classified as PSP-NC or PSP-MCI, converted to dementia, with an incidence rate of 241 per 1,000 patients/year. Nineteen out of 21 PSP patients (90%) developed the behavioural variant frontotemporal dementia phenotype. The only factor associated with conversion to dementia was MCI diagnosis at baseline (p = 0.023). CONCLUSION: Cognitive decline occurs in a great proportion of PSP-RS patients early during the disease course. In the absence of a specific phenotype, the diagnosis of MCI might identify PSP patients at greatest risk of developing dementia and should be considered further in the diagnostic assessment.

Neuropsychological assessment in different King's clinical stages of amyotrophic lateral sclerosis.

Emerging evidence shows that cognitive deficits associated with frontal lobe dysfunction occur from early stages of amyotrophic lateral sclerosis (ALS). We aimed to assess neuropsychological functioning at different stages of ALS to further delineate the occurrence of cognitive impairment alongside the trajectory of ALS as defined by standard assessment procedures. We investigated several cognitive domains in 74 ALS patients classified into four different clinical stages of disease, according to a recently validated staging system for ALS (known as 'King's' system), and evaluated and compared the corresponding cognitive profiles. We found that data derived from global cognitive assessment and several executive (i.e. Frontal Assessment Battery and Trail Making Test B-A) and long-term memory (i.e. memory prose) tests were significantly different among the subsets of ALS patients, showing poorer performances with increasing clinical disability. In conclusion, our preliminary results support the notion that mainly frontotemporal abilities may be impaired during the ALS course and suggest that neuropsychological information could supplement the current clinical staging of patients. However, ALS-specific multi-domain screening instruments, which allow to correct neuropsychological scores for physical disability, should be validated in larger populations worldwide and routinely introduced in clinical practice.

Microstructural changes across different clinical milestones of disease in amyotrophic lateral sclerosis.

Neurodegenerative process in amyotrophic lateral sclerosis (ALS) has been proven to involve several cortical and subcortical brain regions within and beyond motor areas. However, how ALS pathology spreads progressively during disease evolution is still unknown. In this cross-sectional study we investigated 54 ALS patients, divided into 3 subsets according to the clinical stage, and 18 age and sex-matched healthy controls, by using tract-based spatial statistics (TBSS) diffusion tensor imaging (DTI) and voxel-based morphometry (VBM) analyses. We aimed to identify white (WM) and gray matter (GM) patterns of disease distinctive of each clinical stage, corresponding to specific clinical milestones. ALS cases in stage 2A (i.e., at diagnosis) were characterized by GM and WM impairment of left motor and premotor cortices and brainstem at ponto-mesenchephalic junction. ALS patients in clinical stage 2B (with impairment of two functional regions) exhibited decreased fractional anisotropy (FA) (p<0.001, uncorrected) and increased mean (MD) and radial diffusivity (RD) (p<0.001, uncorrected) in the left cerebellar hemisphere and brainstem precerebellar nuclei, as well as in motor areas, while GM atrophy (p<0.001, uncorrected) was detected only in the left inferior frontal gyrus and right cuneus. Finally, ALS patients in stage 3 (with impairment of three functional regions) exhibited decreased FA and increased MD and RD (p<0.05, corrected) within WM underneath bilateral pre and postcentral gyri, corpus callosum midbody, long associative tracts and midbrain, while no significant clusters of GM atrophy were observed. Our findings reinforce the hypothesis that the neurodegenerative process propagates along the axonal pathways and develops beyond motor areas from early stages, involving progressively several frontotemporal regions and their afferents and efferents, while the detection of GM atrophy in earlier stages and its disappearance in later stages may be the result of reactive gliosis.