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2.
Lupus ; 32(6): 737-745, 2023 May.
Article in English | MEDLINE | ID: mdl-37036020

ABSTRACT

OBJECTIVE: During the COVID-19 pandemic, many research studies were adapted, including our longitudinal study examining cognitive impairment (CI) in systemic lupus erythematosus (SLE). Cognitive testing was switched from in-person to virtual. This analysis aimed to determine if the administration method (in-person vs. virtual) of the ACR-neuropsychological battery (ACR-NB) affected participant cognitive performance and classification. METHODS: Data from our multi-visit, SLE CI study included demographic, clinical, and psychiatric characteristics, and the modified ACR-NB. Three analyses were undertaken for cognitive performance: (1) all visits, (2) non-CI group visits only and (3) intra-individual comparisons. A retrospective preferences questionnaire was given to participants who completed the ACR-NB both in-person and virtually. RESULTS: We analysed 328 SLE participants who had 801 visits (696 in-person and 105 virtual). Demographic, clinical, and psychiatric characteristics were comparable except for ethnicity, anxiety and disease-related damage. Across all three comparisons, six tests were consistently statistically significantly different. CI classification changed in 11/71 (15%) participants. 45% of participants preferred the virtual administration method and 33% preferred in-person. CONCLUSIONS: Of the 19 tests in the ACR-NB, we identified one or more problems with eight (42%) tests when moving from in-person to virtual administration. As the use of virtual cognitive testing will likely increase, these issues need to be addressed - potentially by validating a virtual version of the ACR-NB. Until then, caution must be taken when directly comparing virtual to in-person test results. If future studies use a mixed administration approach, this should be accounted for during analysis.


Subject(s)
COVID-19 , Lupus Erythematosus, Systemic , Rheumatology , Humans , United States , Lupus Erythematosus, Systemic/complications , Lupus Erythematosus, Systemic/psychology , Retrospective Studies , Longitudinal Studies , Pandemics , COVID-19/complications , Cognition
3.
Eur J Neurol ; 27(7): 1170-1177, 2020 07.
Article in English | MEDLINE | ID: mdl-32281206

ABSTRACT

BACKGROUND/OBJECTIVE: This study aimed to evaluate serum neurofilament light chain (NF-L) levels in former professional contact sports athletes with multiple concussions (ExPro) as a potential biomarker of neurodegeneration and predictor of white-matter (WM) abnormality progression. METHODS: Concentrations of NF-L in the serum of fifty-two cognitively normal ExPro and twenty-one healthy controls (HC) with no history of concussions were measured using single molecule array (Simoa) technology. Both groups underwent neuroimaging at the time of serum collection. Eighteen of the participants in the ExPro underwent follow-up imaging after 2 years. RESULTS: Levels of serum NF-L were not significantly different between the ExPro and HC. However, in the ExPro group, NF-L levels were positively correlated with the mean diffusivity (MD) of corpus callosum (CC) and fornix, and total ventricular volume. Moreover, NF-L levels in the ExPro group at the first visit were positively correlated with the amount of increase in CC MD at the 2-year follow-up. CONCLUSIONS: NF-L levels reflect neuronal changes in the ExPro group and predict the extent of decrease in white matter integrity over time. Serum NF-L might be a biomarker of neurodegeneration and WM abnormality progression in ExPro.


Subject(s)
Brain Concussion , Intermediate Filaments , Athletes , Biomarkers , Brain Concussion/diagnostic imaging , Diffusion Tensor Imaging , Humans , White Matter/diagnostic imaging
4.
Alzheimers Dement ; 16(1): 91-105, 2020 01.
Article in English | MEDLINE | ID: mdl-31914227

ABSTRACT

INTRODUCTION: Leisure activities impact brain aging and may be prevention targets. We characterized how physical and cognitive activities relate to brain health for the first time in autosomal dominant frontotemporal lobar degeneration (FTLD). METHODS: A total of 105 mutation carriers (C9orf72/MAPT/GRN) and 69 non-carriers reported current physical and cognitive activities at baseline, and completed longitudinal neurobehavioral assessments and brain magnetic resonance imaging (MRI) scans. RESULTS: Greater physical and cognitive activities were each associated with an estimated >55% slower clinical decline per year among dominant gene carriers. There was also an interaction between leisure activities and frontotemporal atrophy on cognition in mutation carriers. High-activity carriers with frontotemporal atrophy (-1 standard deviation/year) demonstrated >two-fold better cognitive performances per year compared to their less active peers with comparable atrophy rates. DISCUSSION: Active lifestyles were associated with less functional decline and moderated brain-to-behavior relationships longitudinally. More active carriers "outperformed" brain volume, commensurate with a cognitive reserve hypothesis. Lifestyle may confer clinical resilience, even in autosomal dominant FTLD.


Subject(s)
Cognition/physiology , Exercise , Frontotemporal Lobar Degeneration , Leisure Activities , Neuropsychological Tests/statistics & numerical data , Aged , Atrophy/pathology , Female , Frontotemporal Lobar Degeneration/genetics , Frontotemporal Lobar Degeneration/pathology , Humans , Longitudinal Studies , Magnetic Resonance Imaging , Male , Middle Aged
5.
Brain Struct Funct ; 221(4): 1911-25, 2016 05.
Article in English | MEDLINE | ID: mdl-25721800

ABSTRACT

The frontotemporal cortical network is associated with behaviours such as impulsivity and aggression. The health of the uncinate fasciculus (UF) that connects the orbitofrontal cortex (OFC) with the anterior temporal lobe (ATL) may be a crucial determinant of behavioural regulation. Behavioural changes can emerge after repeated concussion and thus we used MRI to examine the UF and connected gray matter as it relates to impulsivity and aggression in retired professional football players who had sustained multiple concussions. Behaviourally, athletes had faster reaction times and an increased error rate on a go/no-go task, and increased aggression and mania compared to controls. MRI revealed that the athletes had (1) cortical thinning of the ATL, (2) negative correlations of OFC thickness with aggression and task errors, indicative of impulsivity, (3) negative correlations of UF axial diffusivity with error rates and aggression, and (4) elevated resting-state functional connectivity between the ATL and OFC. Using machine learning, we found that UF diffusion imaging differentiates athletes from healthy controls with significant classifiers based on UF mean and radial diffusivity showing 79-84 % sensitivity and specificity, and 0.8 areas under the ROC curves. The spatial pattern of classifier weights revealed hot spots at the orbitofrontal and temporal ends of the UF. These data implicate the UF system in the pathological outcomes of repeated concussion as they relate to impulsive behaviour. Furthermore, a support vector machine has potential utility in the general assessment and diagnosis of brain abnormalities following concussion.


Subject(s)
Brain Concussion/pathology , Brain Concussion/physiopathology , Frontal Lobe/pathology , Frontal Lobe/physiopathology , Impulsive Behavior/physiology , Temporal Lobe/pathology , Temporal Lobe/physiopathology , Adult , Aged , Aggression/physiology , Athletes/psychology , Brain Concussion/diagnosis , Diffusion Tensor Imaging , Female , Football/injuries , Gray Matter/pathology , Gray Matter/physiopathology , Humans , Machine Learning , Magnetic Resonance Imaging , Male , Middle Aged , Neural Pathways/pathology , Neural Pathways/physiopathology , Neuropsychological Tests , Prefrontal Cortex/pathology , Prefrontal Cortex/physiopathology , Sensitivity and Specificity
6.
J Neurol ; 259(6): 1071-80, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22037958

ABSTRACT

Cognitive deficits in behavioral-variant frontotemporal dementia (bvFTD) and AD are linked to frontal and temporal lobe gray matter (GM) pathology. The aim of this study was to assess the relative contribution of white (WM) and GM abnormalities to cognitive dysfunction in bvFTD and AD. Fractional anisotropy (FA) for the corpus callosum, cingulum (Cg), and uncinate fasciculus (Unc) was determined in 17 bvFTD and 10 AD patients who underwent neuropsychological testing. Regressions were performed to assess the relative contribution of WM and GM abnormalities to cognitive deficits. Multiple regression analysis revealed that in bvFTD, the left anterior Cg FA was related to executive function, the right anterior Cg FA to visual-spatial attention and working memory, the right posterior Cg to visual-constructional abilities and the left Unc FA to Modified Trails Errors. After adding corresponding GM volumes, the left anterior Cg FA, the right anterior cingulate FA, the right posterior cingulate FA and the left uncinate FA remained significant predictors of the cognitive tasks. In the AD group, the left posterior Cg FA and right descending Cg FA were related to visual recall performance but did not remain significant predictors when GM volumes were added to the regression. These results suggest that reduced integrity of specific WM tracts contribute to cognitive deficits observed in bvFTD after accounting for GM atrophy. In AD, memory impairment was related to WM tract injury but this relationship was no longer observed when GM volumes were included.


Subject(s)
Cognition Disorders/pathology , Executive Function/physiology , Frontal Lobe/pathology , Frontotemporal Dementia/pathology , Nerve Fibers, Myelinated/pathology , Adult , Aged , Aged, 80 and over , Cognition Disorders/physiopathology , Cognition Disorders/psychology , Corpus Callosum/pathology , Diffusion Tensor Imaging/methods , Female , Frontotemporal Dementia/physiopathology , Frontotemporal Dementia/psychology , Humans , Male , Middle Aged , Neuropsychological Tests
8.
Neurology ; 72(14): 1236-41, 2009 Apr 07.
Article in English | MEDLINE | ID: mdl-19349603

ABSTRACT

BACKGROUND: Primary lateral sclerosis (PLS) is an idiopathic upper motor neuron degenerative disorder. The aim of this study was to compare brain volumes in patients with PLS and controls and determine whether differences were due to loss of gray matter (GM), white matter (WM), or both. METHODS: T1-weighted images were acquired in patients with PLS and controls. Freesurfer was used for volumetric segmentation of whole brain, cortical GM, precentral and postcentral cortex, WM, corpus callosum, basal ganglia, thalamus, cerebellum, and CSF. Relationships were sought between disease severity, disease duration, age and brain volumes. RESULTS: Eleven patients with PLS and 10 age-matched healthy controls were included in this study. Compared to control subjects, patients with PLS had significantly smaller whole brain (p = 0.043), frontal lobe (p = 0.036), precentral cortex (p = 0.016), and corpus callosum (p = 0.036) volumes. There was a trend toward a smaller thalamus (p = 0.051). Disease severity correlated with ventricular CSF volume (rho = -0.604, p = 0.025) and precentral cortex volume loss (rho = 0.599, p = 0.026). Disease duration tended to correlate with a loss of WM (rho = -0.636, p = 0.063). CONCLUSIONS: Our results suggest that there is focal atrophy in patients with primary lateral sclerosis compared with controls especially in the precentral cortex and the corpus callosum, specifically where there is transfer of motor fibers.


Subject(s)
Brain/pathology , Motor Neuron Disease/pathology , Aged , Atrophy , Cerebral Cortex/pathology , Corpus Callosum/pathology , Disease Progression , Electromyography , Female , Humans , Image Processing, Computer-Assisted , Magnetic Resonance Imaging , Male , Middle Aged , Motor Neurons/pathology
10.
Eur J Neurol ; 15(4): 413-9, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18353127

ABSTRACT

Fatigue is one of the most disabling symptoms in multiple sclerosis (MS) and there is increasing evidence it has a central origin. Our aim was to assess the impact of mental fatigue on motor task-related cerebral activation. Ten relapsing-remitting MS patients with fatigue were recruited and compared with seven controls. Functional magnetic resonance imaging (fMRI) data were acquired while subjects performed a finger-thumb apposition task. The Paced-Auditory-Serial Addition Task (PASAT) was administered to induce fatigue and the fMRI motor paradigm was then repeated. Our results revealed that the PASAT altered the MS patients' activation patterns on the motor task. After the mentally fatiguing PASAT task, repeating the motor task was associated with patients recruiting significantly more of their brain including bilateral cingulate gyri and left primary sensory cortex, while activating less of the left premotor and supplementary motor area. The control subjects decreased their level of activation after the PASAT. Our current results reveal that a challenging mental task can alter the pattern and increase the volume of cerebral activation on an unrelated motor task in fatigued MS patients. These data support the hypothesis that a substrate for MS fatigue could be a generally elevated demand placed on functioning neural circuits.


Subject(s)
Cerebral Cortex/physiopathology , Mental Fatigue/pathology , Multiple Sclerosis/pathology , Adult , Brain Mapping , Cerebral Cortex/blood supply , Female , Humans , Image Processing, Computer-Assisted/methods , Magnetic Resonance Imaging/methods , Male , Mental Fatigue/complications , Middle Aged , Motor Activity , Multiple Sclerosis/complications , Neuropsychological Tests , Oxygen/blood , Task Performance and Analysis
11.
Can J Neurol Sci ; 35(5): 583-7, 2008 Nov.
Article in English | MEDLINE | ID: mdl-19235441

ABSTRACT

OBJECTIVES: The current management of acute ischemic stroke is intravenous (IV) recombinant tissue plasminogen activator (rtPA). The presence of a hyperdense middle cerebral artery sign (HMCAS) on pre-treatment head computed tomogram (CT) is considered a poor prognostic sign. We compared the clinical outcome in IV rtPA-treated patients with and without a HMCAS. DESIGN: Retrospective analysis of prospectively collected cases treated with IV rtPA within three hours. Inclusion criteria were the presence of: i) an anterior circulation stroke; ii) a pre-treatment CT available; iii) a pre-treatment National Institutes of Health (NIH) stroke scale (NIHSS) score; and iv) a modified Rankin Score (mRS) at three months. RESULTS: One hundred and thirty patients were eligible for the analysis, 64 (49%) had a HMCAS. The HMCAS group had a trend toward a higher mean (+/-SD) pre-treatment NIHSS score compared to the non-HMCAS group (13.9+/-6 vs. 12.2+/-6; p=0.12). Accordingly, there were more patients with severe strokes (NIHSS>10) in the HMCAS group compared to the non-HMCAS one (48/64=75% vs. 35/66=53%; p=0.009). The mean (+/-SD) NIHSS score 24 hours after treatment was 10.6 (+/-8) in the HMCAS group and 8.3 (+/-7) in the non-HMCAS group (p=0.08). In a multiple logistic regression analysis, the only independent predictor of poor outcome (mRS 3-6) was pre-treatment NIHSS score (p<0.001). CONCLUSION: Patients with a HMCAS receiving IV rtPA did not fare worse at three months despite a greater proportion of patients with more severe strokes. Based on the current knowledge, IV rtPA remains a good treatment for patients with a HMCAS within three hours of symptom onset.


Subject(s)
Emergency Medical Services/methods , Fibrinolytic Agents/administration & dosage , Infarction, Middle Cerebral Artery/drug therapy , Middle Cerebral Artery/drug effects , Stroke/drug therapy , Tissue Plasminogen Activator/administration & dosage , Acute Disease/therapy , Aged , Aged, 80 and over , Disability Evaluation , Emergency Medical Services/statistics & numerical data , Female , Humans , Infarction, Middle Cerebral Artery/pathology , Infarction, Middle Cerebral Artery/physiopathology , Injections, Intravenous/statistics & numerical data , Logistic Models , Male , Middle Aged , Middle Cerebral Artery/pathology , Middle Cerebral Artery/physiopathology , Recombinant Fusion Proteins/administration & dosage , Retrospective Studies , Stroke/pathology , Stroke/physiopathology , Time , Treatment Outcome
12.
Mult Scler ; 13(8): 985-95, 2007 Sep.
Article in English | MEDLINE | ID: mdl-17468448

ABSTRACT

We determined biopsychosocial correlates of general, physical, and mental fatigue in MS patients, by evaluating the additional contribution of potentially modifiable factors after accounting for non-modifiable disease-related factors. Fifty-three ambulatory MS patients, along with 28 normal controls were recruited for a cross-sectional study. Subjects completed the Multidimensional Fatigue Inventory (MFI) and Fatigue Severity Scale. Potential correlates evaluated were: disease-related factors (disease duration and type, immunomodulating treatment, muscle strength, pain, forced vital capacity (FVC), respiratory muscle strength, body mass index, disability, fibromyalgia), behavioural factors (physical activity, sleep quality) and psychosocial factors (depression, stress, self-efficacy). Multivariate models were calculated for MFI General, Physical, and Mental Fatigue. Age-adjusted multivariate models with non-modifiable factors included the following predictors (P < or = 0.10) of 1) MFI General and Mental Fatigue: none; and 2) MFI Physical Fatigue: FVC and disability. The following potentially modifiable predictors (P < or = 0.10) made an additional contribution to the models 1) MFI General Fatigue: sleep quality, self-efficacy, pain; 2) MFI Physical Fatigue: self-efficacy, physical activity; and 3) MFI Mental Fatigue: stress, self-efficacy. Fatigue in MS is multidimensional. Correlates of general and physical fatigue are disease-related, behavioural and psychosocial factors. Correlates of mental fatigue are psychosocial factors. Potentially modifiable factors account for a considerable portion of fatigue.


Subject(s)
Attitude to Health , Multiple Sclerosis/physiopathology , Multiple Sclerosis/psychology , Adult , Aged , Cross-Sectional Studies , Fatigue/physiopathology , Female , Humans , Male , Middle Aged , Multiple Sclerosis, Chronic Progressive/physiopathology , Multiple Sclerosis, Chronic Progressive/psychology , Multiple Sclerosis, Relapsing-Remitting/physiopathology , Multiple Sclerosis, Relapsing-Remitting/psychology , Reference Values , Self Efficacy
13.
J Neurol ; 249(10): 1382-90, 2002 Oct.
Article in English | MEDLINE | ID: mdl-12382153

ABSTRACT

OBJECTIVE: Our aim was to determine if the resonance intensity of choline-containing compounds (Cho) measured using proton magnetic resonance spectroscopy (MRS) was increased in pre-lesional normal appearing white matter (NAWM) in patients with multiple sclerosis (MS) relative to NAWM that remained stable in subsequent scans. BACKGROUND: The Cho peak in MR spectra is associated with membrane phospholipids and increases in acute MS plaques, possibly even before the appearance of MRI-visible MS lesions. METHODS: Three combined proton MRI and MRS imaging examinations of the corpus callosum and adjacent periventricular white matter were performed on 12 MS patients at intervals of 6 months. Proton density (PD) images were visually matched across 3 time points and the lesion volume in each voxel of the volume of interest was determined. The voxels were subdivided into four groups based on the presence or absence of lesion at baseline and change or no change in lesion volume on the subsequent scan. RESULTS: We found a significantly higher baseline Cho/Creatine (Cr) ratio in NAWM voxels that displayed MRI visible lesions 6 months later than NAWM voxels that remained unchanged (1.57 +/- 0.30 and 1.37 +/- 0.33, respectively, p < 0.001). The 12-month interval data revealed similar pre-lesional elevated Cho/Cr, (1.51 +/- 0.29 versus 1.39 +/- 0.32, p = 0.009). Voxels that contained lesion at baseline and increased in lesion volume at 6 months also showed a significantly higher Cho/Cr ratio than those whose lesion volume did not change (1.60 +/- 0.32 and 1.49 +/- 0.36, respectively, p = 0.043). CONCLUSIONS: The results of this study are consistent with focal pre-lesional myelin membrane pathology in the NAWM at least 12 months before lesions become visible on conventional MRI. This could reflect altered myelin chemistry or the presence of inflammation as seen in experimental allergic encephalomyelitis.


Subject(s)
Brain/metabolism , Choline/metabolism , Magnetic Resonance Spectroscopy , Multiple Sclerosis/metabolism , Adult , Brain/pathology , Female , Humans , Image Processing, Computer-Assisted , Male , Middle Aged , Multiple Sclerosis/pathology , Time Factors
14.
Arch Neurol ; 58(1): 65-70, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11176938

ABSTRACT

OBJECTIVE: To assess axonal damage and its contribution to disability at different stages of multiple sclerosis (MS). BACKGROUND: Recent in vivo imaging and in situ pathologic studies have demonstrated that substantial axonal damage accompanies the inflammatory lesions of MS. However, the relation of axonal damage to the duration of MS and its contribution to disability at different stages of the disease remain poorly defined. DESIGN: We performed proton magnetic resonance spectroscopic imaging in 88 patients with a wide range of clinical disability and disease duration to measure N-acetylaspartate (NAA, an index of axonal integrity) relative to creatine (Cr) in a large central brain volume that included mostly normal-appearing white matter on magnetic resonance imaging. RESULTS: We observed that the NAA/Cr values were abnormally low in the early stages of MS, even before significant disability (measured using the Expanded Disability Status Scale [EDSS]) was evident clinically, and declined more rapidly with respect to EDSS at lower than at higher EDSS scores (P<.001). The correlation of NAA/Cr values with EDSS score was significantly (P<.03) stronger in patients with mild disability (EDSS score <5, Spearman rank order correlation = -0.54, P<.001) than in patients with more severe disability (EDSS score >/=5, Spearman rank order correlation = -0.1, P<.9). When similar analyses were performed in patients with MS grouped for duration of disease, the subgroup with early disease duration (<5 years) also showed central brain NAA/Cr resonance intensity ratios significantly lower than healthy controls (P<.001). CONCLUSION: Cerebral axonal damage begins and contributes to disability from the earliest stages of the disease.


Subject(s)
Aspartic Acid/analogs & derivatives , Axons/pathology , Brain/pathology , Multiple Sclerosis/diagnosis , Adult , Aspartic Acid/metabolism , Atrophy/pathology , Brain/metabolism , Chromatography, High Pressure Liquid , Creatine/metabolism , Disability Evaluation , Disease Progression , Female , Humans , Magnetic Resonance Imaging , Magnetic Resonance Spectroscopy , Male , Middle Aged , Multiple Sclerosis/metabolism , Severity of Illness Index , Spinal Cord/pathology , Time Factors
15.
Muscle Nerve ; 23(2): 175-81, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10639607

ABSTRACT

The purpose of this study was to assess the effect of physical deconditioning on skeletal muscle's oxidative metabolism as evaluated by phosphorus-31 magnetic resonance spectroscopy ((31)P MRS). Twenty-seven subjects without muscle disease, representing a wide range of fitness levels, were evaluated with (31)P MRS. Spectra were obtained at rest and during recovery from in-magnet exercise. The data show a significant correlation between maximum resting metabolic equivalent (MET) score and the following (31)P MRS recovery indices: adenosine diphosphate and phosphocreatine recovery half-time; initial phosphocreatine resynthesis rate; calculated estimation of mitochondrial capacity; pH at end of exercise; and phosphocreatine depletion. In addition, significant differences between the deconditioned and conditioned group were found for all of the aforementioned recovery indices. At rest, only the inorganic phosphate concentration was significantly different between the two groups. These data indicate that physical activity level should be taken into account when assessing patients' oxidative metabolism with (31)P MRS.


Subject(s)
Muscle, Skeletal/physiology , Phosphorus/physiology , Physical Fitness/physiology , Adenosine Diphosphate/metabolism , Adult , Exercise/physiology , Female , Humans , Magnetic Resonance Spectroscopy , Male , Middle Aged , Mitochondria, Muscle/metabolism , Muscle, Skeletal/metabolism , Oxidation-Reduction , Phosphates/metabolism , Phosphocreatine/biosynthesis , Phosphocreatine/metabolism , Phosphorus/metabolism , Phosphorus Radioisotopes , Rest/physiology
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