Thalamic atrophy predicts cognitive impairment in relapsing remitting multiple sclerosis. Effect on instrumental activities of daily living and employment status

The relationship between work difficulties and physical disability, cognitive and social cognitive impairment and subcortical gray matter atrophy in persons with multiple sclerosis

BACKGROUND

Multiple sclerosis (MS) is commonly associated with work difficulties. This study aimed to examine the relationship between work difficulties and physical disability, cognitive and social cognitive impairment, and subcortical gray matter (scGM) atrophy in pwMS.

METHODS

Thirty-three employees with MS underwent assessments with Multiple Sclerosis Work Difficulties Questionnaire-23 MSWDQ-23. Physical disability was measured using EDSS, Timed 25-Foot Walk (T25FW), 2-Minute Walking Test (2-MWT), the Nine-Hole Peg test (N-HPT), and 12-item Multiple Sclerosis Walking Scale (MSWS-12). Cognitive functions were evaluated with Brief International Cognitive Assessment in MS (BICAMS), social cognition with Facial Emotion Identification (FEI), Reading the Mind in the Eyes Test (RMET), and Empathy Quotient (EQ). Anxiety and depression were assessed using Hospital Anxiety and Depression Scale (HADS). The association between variables was analysed using Spearman's correlation coefficient. GM volumes were calculated from 3T MRI data using Freesurfer, their potential relationship with work difficulties were evaluated through a linear regression model.

RESULTS

MSWDQ-23 was strongly correlated with T25FW and MSWS-12 (p < 0.01), moderately correlated with EDSS, 2MWT, HAD, BICAMS, and EQ (p < 0.05). According to the linear regression model the decrease in volumes of total GM and scGM, bilateral Thalamus, bilateral Hippocampus, left Putamen, and right Caudate related with the severity of work difficulties (R²=0.815, p = 0.25).

CONCLUSION

This study provides valuable insights into the multifaceted nature of work difficulties experienced by pwMS. It suggests that not only physical disability but also other factors, such as mood, cognition, empathy, and cortical and subcortical gray matter atrophy may contribute to work difficulties among pwMS.

Reduced alpha2 power is associated with slowed information processing speed in multiple sclerosis

OBJECTIVE

Cognitive impairment is common in multiple sclerosis (MS), significantly impacts daily functioning, is time-consuming to assess, and is prone to practice effects. We examined whether the alpha band power measured with magnetoencephalography (MEG) is associated with the different cognitive domains affected by MS.

METHODS

Sixty-eight MS patients and 47 healthy controls underwent MEG, T1- and FLAIR-weighted magnetic resonance imaging (MRI), and neuropsychological testing. Alpha power in the occipital cortex was quantified in the alpha1 (8-10 Hz) and alpha2 (10-12 Hz) bands. Next, we performed best subset regression to assess the added value of neurophysiological measures to commonly available MRI measures.

RESULTS

Alpha2 power significantly correlated with information processing speed (p < 0.001) and was always retained in all multilinear models, whereas thalamic volume was retained in 80% of all models. Alpha1 power was correlated with visual memory (p < 0.001) but only retained in 38% of all models.

CONCLUSIONS

Alpha2 (10-12 Hz) power in rest is associated with IPS, independent of standard MRI parameters. This study stresses that a multimodal assessment, including structural and functional biomarkers, is likely required to characterize cognitive impairment in MS. Resting-state neurophysiology is thus a promising tool to understand and follow up changes in IPS.

The impact of disease modifying therapies on cognitive functions typically impaired in multiple sclerosis patients: a clinician's review

Objective

Over the last few decades clinicians have become aware that cognitive impairment might be a major cause of disability, loss of employment and poor quality of life in patients suffering from multiple sclerosis [MS].The impact of disease modifying therapies [DMTs] on cognition is still a matter of debate. Theoretically, DMTs could exert a substantial beneficial effect by means of reducing neuroinflammation and brain atrophy, which are established correlates of cognitive dysfunction. The aim of the study was to review the evidence concerning the effect of DMTs on cognitive functions.

Methods

PubMed, Scopus, and the European Committee for Treatment and Research in Multiple Sclerosis [ECTRIMS] Library were searched for articles concerning the pediatric and adult populations of patients with multiple sclerosis, including clinical trials and RWD, where psychometric results were analyzed as secondary or exploratory endpoints.

Results

We reviewed a total of 44 studies that were found by our search strategy, analyzed the psychological tests that were applied, the length of the follow-up, and possible limitations. We pointed out the difficulties associated with assessing of DMTs' effects on cognitive functions, and pitfalls in cognitive tools used for evaluating of MS patients.

Conclusion

There is a need to highlight this aspect of MS therapies, and to collect adequate data to make informed therapeutic decisions, to improve our understanding of MS-related cognitive dysfunction and provide new therapeutic targets.

Cognitive impairment in paediatric onset multiple sclerosis and its relation to thalamic volume and cortical thickness of temporal lobe by magnetic resonance imaging

Background

Pediatric onset multiple sclerosis (POMS), defined as an age at onset younger than 18 years, which occurs in 5% of patients with MS. cognitive dysfunction is one of the prominent disabling sequelae of Multiple sclerosis. Brain volumetric studies by magnetic resonance images revealed the decline of whole and regional brain volumes along the disease course. This work aimed to investigate the relationship between cognitive impairment in pediatric MS patients with thalamic atrophy and cortical thickness of temporal lobe. This study included 50 patients who were diagnosed as POMS and 50 healthy control participants matched for age and sex. Both groups were compared for volumetric measurements of thalamic volumes and temporal lobes cortical thickness using a computerized program called FreeSurfer.MS group was evaluated for cognitive dysfunction using Arabic version of fifth edition of Standford–Benit test. A correlation between volumetric results and neuropsychological evaluation of MS group was done.

Results

Our study showed that the MS group has the lowest value regarding their thalamic volumes and their cortical thickness of temporal lobes in relation to the healthy control group, while there was a significant relation between cognitive impairment and decrease in thalamic volume and specific areas in cortical thickness, such as superior temporal thickness, middle temporal thickness, inferior temporal thickness, fusiform thickness and para hippocampal thickness of temporal lobe in pediatric onset MS patients.

Conclusions

POMS affects specific brain areas such as thalamus and cortical thickness of temporal lobes regarding their volume and thickness which influence the neuropsychological evaluation detected by Standford–Benit test.

Predictive Value of the Third Ventricle Width for Neurological Status in Multiple Sclerosis

The third ventricle width (3VW) is an easily calculated measure of brain atrophy. The aim of this study was to evaluate the relation of 3VW to cognitive impairment with adjustment for demographic and clinical confounders, including depression, anxiety, and fatigue, as well as to disability in patients with multiple sclerosis (MS). Symbol Digit Modalities Test, California Verbal Learning Test, Brief Visuospatial Memory Test-Revised, Expanded Disability Status Scale (EDSS), Hospital Anxiety and Depression Scale, and Modified Fatigue Impact Scale (MFIS) were analysed in 93 patients with MS. Neuropsychological performance was compared to that of 150 healthy controls. Axial images from 3D FLAIR were used to measure 3VW. In total, 25% of MS patients were impaired in at least two neuropsychological tests. Cognitive impairment and EDSS were associated with 3VW. Age and 3VW were the strongest predictors of cognitive impairment. The multiple regression model including age, 3VW, education, EDSS, and MFIS explained 63% of the variance of neuropsychological tests results, whereas 3VW, age and duration of the disease were significant predictors of EDSS. This study confirms the predictive value of 3VW for neurological status of patients with MS, especially for cognitive impairment after adjustment for demographic and clinical confounders.

The Two Sides of Siponimod: Evidence for Brain and Immune Mechanisms in Multiple Sclerosis

Siponimod is a selective sphingosine 1-phosphate receptor subtype 1 (S1P₁) and 5 (S1P₅) modulator approved in the United States and the European Union as an oral treatment for adults with relapsing forms of multiple sclerosis (RMS), including active secondary progressive multiple sclerosis (SPMS). Preclinical and clinical studies provide support for a dual mechanism of action of siponimod, targeting peripherally mediated inflammation and exerting direct central effects. As an S1P₁ receptor modulator, siponimod reduces lymphocyte egress from lymph nodes, thus inhibiting their migration from the periphery to the central nervous system. As a result of its peripheral immunomodulatory effects, siponimod reduces both magnetic resonance imaging (MRI) lesion (gadolinium-enhancing and new/enlarging T2 hyperintense) and relapse activity compared with placebo. Independent of these effects, siponimod can penetrate the blood-brain barrier and, by binding to S1P₁ and S1P₅ receptors on a variety of brain cells, including astrocytes, oligodendrocytes, neurons, and microglia, exert effects to modulate neural inflammation and neurodegeneration. Clinical data in patients with SPMS have shown that, compared with placebo, siponimod treatment is associated with reductions in levels of neurofilament light chain (a marker of neuroaxonal damage) and thalamic and cortical gray matter atrophy, with smaller reductions in MRI magnetization transfer ratio and reduced confirmed disability progression. This review examines the preclinical and clinical data supporting the dual mechanism of action of siponimod in RMS.

The clinical and paraclinical correlates of employment status in multiple sclerosis

PURPOSE

To identify the clinical and paraclinical markers of employment status in multiple sclerosis (MS).

METHODS

This was a cross-sectional sub-study investigating 1226 MS patients. To minimalized confounding effect, two groups of patients, matched by sex, age, and education, were selected: 307 patients with full time employment and 153 unemployed patients receiving disability pension. We explored associations between employment status and Expanded Disability Status Scale (EDSS), 25 Foot Walk Test (25FWT), Nine Hole Peg Test (9HPT), Brief International Cognitive Assessment for MS (BICAMS), Paced Auditory Serial Addition Test (PASAT), Beck Depression Inventory (BDI), SLOAN charts (SLOAN), and brain volumetric MRI measures.

RESULTS

Both groups differed significantly on all variables of interest (p < 0.001). In the univariate analyses, EDSS, SDMT (Symbol Digit Modalities Test) adjusted for BDI, 25FWT, and 9HPT best explained variability in vocational status. In multivariate analyses, the combination of EDSS, 25FWT, SDMT, BDI, and corpus callosum fraction (CCF) explained the greatest variability. As a next step, after patients were matched by EDSS, differences in SDMT, 25FWT (both p < 0.001), 9HPT, CCF, and T2 lesion volume were still present (all p < 0.005) between both groups. The best multivariate model consisted of SDMT, BDI, and T2 lesion volume.

CONCLUSIONS

EDSS, walking ability, cognitive performance, and MRI volumetric parameters are independently associated with employment status.

Outcome measures assisting treatment optimization in multiple sclerosis

Objective

To review instruments used to assess disease stability or progression in persons with multiple sclerosis (pwMS) that can guide clinicians in optimizing therapy.

Methods

A non-systematic review of scientific literature was undertaken to explore modalities of monitoring symptoms and the disease evolution of MS.

Results

Multiple outcome measures, or tools, have been developed for use in MS research as well as for the clinical management of pwMS. Beginning with the Expanded Disability Status Scale, introduced in 1983, clinicians and researchers have developed monitoring modalities to assess all aspects of MS and the neurological impairment it causes.

Conclusions

Much progress has been made in recent decades for the management of MS and for the evaluation of disease progression. New technology, such as wearable sensors, will provide new opportunities to better understand changes in function, dexterity, and cognition. Essential work over the decades since EDSS was introduced continues to improve our ability to treat this debilitating disease.

Cortical surface thickness, subcortical volumes and disability between races in relapsing-remitting multiple sclerosis

BACKGROUND

The interplay between cortical surface thickness (CTh), subcortical volumes (SCV) and disability in patients with relapsing remitting multiple sclerosis (RRMS) is still not clear.

OBJECTIVE

To examine the relationship between CTh, SCV, and disability and investigate differences in CTh, SCV and disability between African Americans (AA) and Caucasian Americans (CA).

METHODS

Sixty-five RRMS (33AA, 32 CA) participants underwent Expanded Disability Status Scale and Multiple Sclerosis Functional Composite (MSFC) assessments, including timed 25-foot walk (T25FW), nine-hole peg test (9HPT) on dominant (D) and non-dominant hand (ND) and paced auditory serial addition test (PASAT-3). Symbol digit modalities test (SDMT) was also administered. All participants underwent 3T brain MRI. CTh was measured in the Frontal (FA), Parietal (PA), Temporal (TA), Occipital (OA), Cingulate (CA), and Global (GA) cortical surface areas (CSA). SCV measurements included Thalamus (TV), Caudate (CV), Putamen (PV), Pallidum (PaV), Hippocampus (HV), Amygdala (AV), Accumbens (AcV), Brain Stem (BSV), and Deep Gray Matter Total Volume (DGMTV). A general linear model with multivariate analysis (MANOVA) was used to determine the differences between the two cohorts (SPSS vs 25). Spearman rank correlation analysis was performed to investigate the relationship between CTh and MSFC.

RESULTS

AA have significantly decreased FA, PA, TA, GA CTh compared to CA (p = 0.004, p = 0.018, p = 0.013, p = 0.015, respectively). SCV measurements were not significantly different. Only in CA, the MSFC measures correlate significantly with regional CSA CTh. In both races and in the entire group, T25FW correlates with TV, PV, AV, AcV and DGMTV (p < 0.05). Only in AA and the entire cohort, PASAT-3 correlates with TV and AcV(p = 0.041, p = 0.006, p = 0.006, p = 0.000 respectively).

CONCLUSIONS

Differences in CSA CTh reinforce the different disease pathobiology between AA and CA. Regional CTh may represent a useful biomarker related to multi-domain disability only in CA, while in AA DGM injury might be a more important contributor to disability. Longitudinal, large-scale studies are warranted to confirm our findings.

Early neuropsychological markers of cognitive involvement in multiple sclerosis

BACKGROUND

Cognitive impairment due to multiple sclerosis (MS) is common and often limits occupational functioning, contributes to disability, and reduces quality of life. Early detection of cognitive involvement in MS is critical for treatment planning and intervention, and frequent, regular cognitive monitoring may provide insight into subtle changes in disease progression.

OBJECTIVE

To compare the sensitivity and specificity of clinical, computer-based and experimental measures to early cognitive involvement in MS.

METHODS

Cognitive functioning was compared in MS participants early in the disease course to matched healthy controls using conventional, computer-based and functional assessments: the Brief International Cognitive Assessment in MS (BICAMS); the computer-based Cogstate Brief Battery (CBB); the Attention Network Test-Interaction (ANT-I), including intra-individual variability; and the Test of Everyday Cognitive Ability (TECA), a functional measure of instrumental activities of daily living.

RESULTS

MS participants (n = 25, mean disease duration= 5.82 ± 3.65 years) and demographically matched healthy controls (n = 29) completed the cognitive assessments. The Cogstate measure of choice reaction time (AUC = 0.73, p = .004), intra-individual variability on the ANT-I (AUC = 0.79, p = .001), and TECA (AUC = 0.78, p = .001) scores were the most sensitive and specific markers of cognitive involvement in MS.

CONCLUSIONS

Brief, repeatable, computer-based measures of reaction time and variability detect early MS associated cognitive involvement.

Memantine for Multiple Sclerosis: A Systematic Review and Meta-Analysis of Randomized Trials

Background: Multiple sclerosis (MS), a disabling demyelinating disease of the central nervous system, is associated with cognitive impairment, spasticity, and fatigue. There are still no established guidelines on the management of MS-related sequela. Memantine has the potential to reduce glutamate toxicity, thereby reducing consequent cognitive impairment, spasticity, and fatigue.

Objectives: This study aims to determine the efficacy and safety of memantine in preventing cognitive impairment, reducing spasticity and fatigue, and controlling disability in MS patients through a review of relevant randomized trials.

Methods: MEDLINE, CENTRAL, Scopus, Embase, LILACS, ClinicalTrials.gov, and HERDIN were searched from inception to May 2020 for relevant trials.

Results: The search yielded 203 articles; four studies were included in the analysis. Pooled evidence shows that memantine compared with placebo does not significantly improve PASAT, ASS, MFIS, and EDSS scores of patients with MS. Memantine is associated with mild adverse drug events such as dizziness, fatigue, and anxiety.

Conclusion: There is not enough evidence to support the efficacy of memantine in preventing cognitive decline, controlling spasticity, reducing fatigue, and preventing disability. Future researches should consider the different MS subtypes, effect of co-administration of disease-modifying therapies, longer duration of administration, and more sensitive outcome measures to evaluate the potential benefit of memantine in MS.

The association between MRI brain volumes and computerized cognitive scores of people with multiple sclerosis

BACKGROUND

Computerized cognitive assessment facilitates the incorporation of multi-domain cognitive monitoring into routine clinical care. The predictive validity of computerized cognitive assessment among people with multiple sclerosis (PwMS) has scarcely been investigated.

OBJECTIVE

To explore the associations between brain volumes and cognitive scores from a computerized cognitive assessment battery (CAB, NeuroTrax) among PwMS.

METHODS

PwMS were evaluated with the CAB and underwent brain MRI within 40 days. Cognitive assessment yielded age- and education-adjusted scores in 9 cognitive domains: memory, executive function, attention, information processing speed, visual spatial, verbal function, motor skills, problem solving, and working memory. The global cognitive score (GCS) is the average of all domain scores. MRI brain and lesion volumes were assessed with icobrain ms, a fully automated tissue and lesion segmentation and quantification software.

RESULTS

91 PwMS were included [Age: 52.1 ± 11.7 years, 64 (70%) female, EDSS: 3.4 ± 2.0, 79 (87%) with a relapsing remitting course]. Significant correlations were found between the GCS and whole brain, white matter, grey matter, thalamic, lateral ventricles, hippocampal and lesion volumes (Correlation coefficients: 0.46, 0.40, 0.25, 0.42, -0.36, 0.21, -0.3, respectively). Regression analysis revealed that lateral ventricles and thalamic volumes were the most consistent predictors of all cognitive domain scores.

CONCLUSION

Computerized cognitive scores were significantly associated with quantified MRI. These findings support the predictive validity of multi-domain computerized cognitive assessment for people with multiple sclerosis.

Beyond Alzheimer's disease: Can bilingualism be a more generalized protective factor in neurodegeneration?

Bilingualism has been argued to have an impact on cognition and brain structure. Effects have been reported across the lifespan: from healthy children to ageing adults, including clinical (ageing) populations. It has been argued that active bilingualism may significantly contribute to the delaying of the expression of Alzheimer's disease symptoms. If bilingualism plays an ameliorative role against the expression of neurodegeneration in dementia, it is possible that it could have similar effects for other neurodegenerative disorders, including Multiple Sclerosis, Parkinson's and Huntington's Diseases. To date, however, direct relevant evidence remains limited, not least because the necessary scientific motivations for investigating this with greater depth have not yet been fully articulated. Herein, we provide a roadmap that reviews the relevant literatures, highlighting potential links across neurodegenerative disorders and bilingualism more generally.

The impact of deep grey matter volume on cognition in multiple sclerosis

BACKGROUND

Cognitive dysfunctions are very frequent in people living with multiple sclerosis (MS). Several studies have previously indicated grey matter (GM) atrophy as useful predictor of patients' cognitive impairment. However, considerable uncertainty exists about the possible impact of deep grey matter volumes on cognition. This study aimed to evaluate the relationship of the subcortical (sc) GM volumes with the presence and severity of global and selective cognitive impairment in MS.

METHODS

A group of MS patients with relapsing remitting course were enrolled. Patients underwent a neuropsychological evaluation by using the Brief Repeatable Battery of Neuropsychological Tests (BRBN) and the Delis-Kaplan Executive Function System Sorting Test (D-KEFST); z scores were estimated and items with z score below 2 standard deviation were considered failed. Thus, brain MRIs images were acquired and measurements of whole brain (WB), white matter (WM), and cortical grey matter (GM) were obtained by SIENAX. After FIRST tool segmentation, volumes of subcortical GM structures were also estimated.

RESULTS

The sample included 50 MS patients, of which 16/50 (32%) subjects were cognitively impaired. Multiple regression analyses found a significant association of severity of cognitive impairment, defined as number of failed neuropsychological tests, with lower volumes of cortex (p=0.003), thalamus (p=0.009), caudate (p=0.011), putamen (p=0.020), pallidus (p=0.012) and hippocampus (p=0.045), independently from other MS features. In addition, an association between accumbens volume and D-KEFS ST FSC and D-KEFS ST FSD z scores was observed (p<0.03).

CONCLUSIONS

Our results indicated that volumes of several scGM structures, and in particular of thalamus, contribute to determine cognitive dysfunctions in MS, mainly influencing the executive functioning. Further investigations in larger MS cohorts with cognitive impairment are necessary to better understand the structural brain damage underlying this "invisible disability".

Cognitive processing speed in multiple sclerosis clinical practice: association with patient-reported outcomes, employment and magnetic resonance imaging metrics

BACKGROUND AND PURPOSE

To analyze the relationship between cognitive processing speed, patient-reported outcome measures (PROMs), employment and magnetic resonance imaging (MRI) metrics in a large multiple sclerosis cohort.

METHODS

Cross-sectional clinical data, PROMs, employment and MRI studies within 90 days of completion of the Processing Speed Test (PST), a technology-enabled adaptation of the Symbol Digit Modalities Test, were collected. MRI was analyzed using semi-automated methods. Correlations of PST score with PROMs and MRI metrics were examined using Spearman's rho. Wilcoxon rank sum testing compared MRI metrics across PST score quartiles and linear regression models identified predictors of PST performance. Effects of employment and depression were also investigated.

RESULTS

In 721 patients (mean age 47.6 ± 11.4 years), PST scores were significantly correlated with all MRI metrics, including cord atrophy and deep gray matter volumes. Linear regression demonstrated self-reported physical disability, cognitive function, fatigue and social domains (adjusted R²  = 0.44, P < 0.001) as the strongest clinical predictors of PST score, whereas that of MRI variables included T2 lesion volume, whole-brain fraction and cord atrophy (adjusted R²  = 0.42, P < 0.001). An inclusive model identified T2 lesion volume, whole-brain fraction, self-reported upper extremity function, cognition and social participation as the strongest predictors of PST score (adjusted R²  = 0.51, P < 0.001). There was significant effect modification by depression on the relationship between self-reported cognition and PST performance. Employment status was associated with PST scores independent of age and physical disability.

CONCLUSION

The PST score correlates with PROMs, MRI measures of focal and diffuse brain injury, and employment. The PST score is a feasible and meaningful measure for routine multiple sclerosis care.

Early putamen hypertrophy and ongoing hippocampus atrophy predict cognitive performance in the first ten years of relapsing-remitting multiple sclerosis

BACKGROUND

The first years of relapsing-remitting multiple sclerosis (RRMS) constitute the most vulnerable phase for the progression of cognitive impairment (CImp), due to a gradual decrease of compensatory mechanisms. In the first 10 years of RRMS, the temporal volumetric changes of deep gray matter structures must be clarified, since they could constitute reliable cognitive biomarkers for diagnostic, prognostic, and therapeutic purposes.

METHODS

Forty-five cognitively asymptomatic patients with RRMS lasting ≤ 10 years, and with a brain MRI performed in a year from the neuropsychological evaluation (Te-MRI), were included. They performed the Brief International Cognitive Assessment battery for MS. Thirty-one brain MRIs performed in the year of diagnosis (Td-MRI) and 13 brain MRIs of age- and sex-matched healthy controls (HCs) were also included in the study. The relationships between clinical features, cognitive performances, and Te- and Td-MRI volumes were statistically analyzed.

RESULTS

Cognitively preserved (CP) patients had significantly increased Td-L-putamen (P = 0.035) and Td-R-putamen volume (P = 0.027) with respect to cognitively impaired (CI) ones. CI patients had significantly reduced Te-L-hippocampus (P = 0.019) and Te-R-hippocampus volume (P = 0.042) compared, respectively, with Td-L-hippocampus and Td-R-hippocampus volume. Td-L-putamen volume (P = 0.011) and Te-L-hippocampus volume (P = 0.023) were independent predictors of the Symbol Digit Modalities Test score in all patients (r2 = 0.31, F = 6.175, P = 0.001).

CONCLUSION

In the first years of RRMS, putamen hypertrophy and hippocampus atrophy could represent promising indices of cognitive performance and reserve, and become potentially useful tools for diagnostic, prognostic, and therapeutic purposes.

Brain atrophy and employment in multiple sclerosis patients: a 10-year follow-up study

Background

Multiple sclerosis is often associated with unemployment. The contribution of grey matter atrophy to unemployment is unclear.

Objectives

To identify magnetic resonance imaging biomarkers of grey matter and clinical symptoms associated with unemployment in multiple sclerosis patients.

Methods

Demographic, clinical data and 1.5 T magnetic resonance imaging scans were collected in 81 patients at the time of inclusion and after 5 and 10 years. Global and tissue-specific volumes were calculated at each time point. Statistical analysis was performed using a mixed linear model.

Results

At baseline 31 (38%) of the patients were unemployed, at 5-year follow-up 44 (59%) and at 10-year follow-up 34 (81%) were unemployed. The unemployed patients had significantly lower subcortical deep grey matter volume (P < 0.001), specifically thalamus, pallidus, putamen and hippocampal volumes, and cortical volume (P = 0.011); and significantly greater T1 (P < 0.001)/T2 (P < 0.001) lesion volume than the employed patient group at baseline. Subcortical deep grey matter volumes, and to a lesser degree cortical volume, were significantly associated with unemployment throughout the follow-up.

Conclusion

We found significantly greater atrophy of subcortical deep grey matter and cortical volume at baseline and during follow-up in the unemployed patient group. Atrophy of subcortical deep grey matter showed a stronger association to unemployment than atrophy of cortical volume during the follow-up.

Brain atrophy in multiple sclerosis: mechanisms, clinical relevance and treatment options

Multiple sclerosis (MS) is an immune-mediated disease of the central nervous system characterized by focal or diffuse inflammation, demyelination, axonal loss and neurodegeneration. Brain atrophy can be seen in the earliest stages of MS, progresses faster compared to healthy adults, and is a reliable predictor of future physical and cognitive disability. In addition, it is widely accepted to be a valid, sensitive and reproducible measure of neurodegeneration in MS. Reducing the rate of brain atrophy has only recently been incorporated as a critical endpoint into the clinical trials of new or emerging disease modifying drugs (DMDs) in MS. With the advent of easily accessible neuroimaging softwares along with the accumulating evidence, clinicians may be able to use brain atrophy measures in their everyday clinical practice to monitor disease course and response to DMDs. In this review, we will describe the different mechanisms contributing to brain atrophy, their clinical relevance on disease presentation and course and the effect of current or emergent DMDs on brain atrophy and neuroprotection.

Gray matter integrity predicts white matter network reorganization in multiple sclerosis

Multiple sclerosis (MS) is a chronic inflammatory and neurodegenerative disease leading to gray matter atrophy and brain network reconfiguration as a response to increasing tissue damage. We evaluated whether white matter network reconfiguration appears subsequently to gray matter damage, or whether the gray matter degenerates following alterations in white matter networks. MRI data from 83 patients with clinically isolated syndrome and early relapsing-remitting MS were acquired at two time points with a follow-up after 1 year. White matter network integrity was assessed based on probabilistic tractography performed on diffusion-weighted data using graph theoretical analyses. We evaluated gray matter integrity by computing cortical thickness and deep gray matter volume in 94 regions at both time points. The thickness of middle temporal cortex and the volume of deep gray matter regions including thalamus, caudate, putamen, and brain stem showed significant atrophy between baseline and follow-up. White matter network dynamics, as defined by modularity and distance measure changes over time, were predicted by deep gray matter volume of the atrophying anatomical structures. Initial white matter network properties, on the other hand, did not predict atrophy. Furthermore, gray matter integrity at baseline significantly predicted physical disability at 1-year follow-up. In a sub-analysis, deep gray matter volume was significantly related to cognitive performance at baseline. Hence, we postulate that atrophy of deep gray matter structures drives the adaptation of white matter networks. Moreover, deep gray matter volumes are highly predictive for disability progression and cognitive performance.

Virtual reality in multiple sclerosis rehabilitation: A review on cognitive and motor outcomes

Multiple sclerosis (MS) is a demyelinating neurodegenerative disease with lesions involving the central nervous system. Clinical symptoms consist of disturbances in motor activity (e.g., weakness, spasticity, and tremor), sensory functioning (e.g., pain), visual functions (e.g., diplopia and optic neuritis), besides different cognitive (attention deficit and executive dysfunction) and behavioral abnormalities. This review aims to evaluate the role of VR tools in cognitive and motor rehabilitation of MS patients. Studies performed between 2010 and 2017 and fulfilling the selected criteria were searched on PubMed, Scopus, Cochrane and Web of Sciences databases, by combining the terms "VR rehabilitation" and "MS". Our findings showed that, following the use of VR training, MS patients presented a significant improvement in motor (especially gait and balance) and cognitive function (with regard to executive and visual-spatial abilities, attention and memory skills). This review supports the idea that rehabilitation through new VR tools could positively affect MS patients' outcomes, by boosting motivation and participation with a better response to treatment.

Aerobic Fitness and Instrumental Activities of Daily Living in People with Multiple Sclerosis: A Cross-sectional Study

Background

There is ample evidence that aerobic fitness is reduced in people with multiple sclerosis (MS), and this may yield a reduction in independence in instrumental activities of daily living (IADLs). This study examined the association between aerobic fitness and self-reported IADLs in persons with MS.

Methods

Sixty-two adults with MS completed an incremental exercise test as a measure of aerobic fitness (peak oxygen consumption), a demographic questionnaire, and an IADL scale and underwent a neurologic examination for characterization of disability level (ie, Expanded Disability Status Scale) in a single session.

Results

The analysis revealed a weak but significant association between aerobic fitness and total IADL score (r = 0.28 [95% CI, 0.03-0.49], P = .033). Those reporting dependence in different IADL categories (eg, shopping, food preparation, housekeeping, laundry, and responsibility for own medication) presented with lower aerobic fitness compared with those reporting independence, although the difference was not statistically significant.

Conclusions

These findings extend previous studies on activities of daily living in people with MS and underscore the need for studies examining the potential effect of aerobic exercise interventions on independence regarding IADLs in this population.

Identification of Cortical and Subcortical Correlates of Cognitive Performance in Multiple Sclerosis Using Voxel-Based Morphometry

Objective: Cognitive impairment is an important feature in multiple sclerosis (MS) and has been associated to several Magnetic Resonance Imaging (MRI) markers, but especially brain atrophy. However, the relationship between specific neuropsychological tests examining several cognitive functions and brain volumes has been little explored. Furthermore, because MS frequently damage subcortical regions, it may be an interesting model to examine the role of subcortical areas in cognitive functioning. Our aim was to identify correlations between specific brain regions and performance in neuropsychological tests evaluating different cognitive functions in a large series of patients with MS.

Methods: A total of 375 patients were evaluated with a comprehensive neuropsychological battery and with MRI. Voxel-based morphometry was conducted to analyse the correlation between cognitive performance and gray matter damage, using Statistical Parametric Mapping with the toolboxes VBM8 and Lesion Segmentation Tool.

Results: The following correlations were found: Corsi block-tapping test with right insula; Trail Making Test with caudate nucleus, thalamus, and several cortical regions including the posterior cingulate and inferior frontal gyrus; Symbol Digit Modalities Test with caudate nucleus, thalamus, posterior cingulate, several frontal regions, insula, and cerebellum; Stroop Color and Word Test with caudate nucleus and putamen; Free and Cued Selective Reminding Test and Rey-Osterrieth Complex Figure with thalamus, precuneus, and parahippocampal gyrus; Boston Naming Test with thalamus, caudate nucleus, and hippocampus; semantic verbal fluency with thalamus and phonological verbal fluency with caudate nucleus; and Tower of London test with frontal lobe, caudate nucleus, and posterior cingulate.

Conclusion: Our study provides valuable data on the cortical and subcortical basis of cognitive function in MS. Neuropsychological tests mainly assessing attention and executive function showed a stronger association with caudate volume, while tests primarily evaluating memory were more strongly correlated with the thalamus. Other relevant regions were the posterior cingulate/precuneus, which were associated with attentional tasks, and several frontal regions, which were found to be correlated with planning and higher order executive functioning. Furthermore, our study supports the brain vertical organization of cognitive functioning, with the participation of the cortex, thalamus, basal ganglia, and cerebellum.

[Brain atrophy and perfusion changes in patients with remitting and secondary progressive multiple sclerosis]

AIM

To study the relationship of brain atrophy and changes in perfusion with an increase in the level of disability in patients with multiple sclerosis (MS).

MATERIAL AND METHODS

Twenty patients with remitting MS, 20 patients with secondary progressive multiple sclerosis (SPMS) and 20 healthy people were studied. The level of neurological deficit was assessed with EDSS and cognitive status with PASAT. MRI of the brain (standard impulse sequences and 3D-T1-MPR for voxel MRI-morphometry) and perfusion computed tomography with the assessment of visually intact white matter (VIWM) and thalamus were performed.

RESULTS

Compared to the control group, patients with MS had a significant atrophy of subcortical gray matter. Patients with SPMS in addition had an atrophy of some cortical areas which was correlated with EDSS scores (p<0.05). The correlation between cognitive impairment and the volume of the left inferior parietal lobule (r=0.677; p=0.011) and worsening of perfusion of VIWM of frontal and parietal lobes, thalamus on both sides was observed in patients with SPMS compared to those with remitting MS. That was correlated with cognitive performance assessed by PASAT.

CONCLUSION

Patterns of atrophy distribution in different types of MS were determined. The level of disability is correlated with the severity of brain atrophy. Hypoperfusion of VIWM that was correlated with cognitive impairment was found in patients with SPMS.

Functional Connectivity Alterations Reveal Complex Mechanisms Based on Clinical and Radiological Status in Mild Relapsing Remitting Multiple Sclerosis

Resting state functional MRI (rs-fMRI) has provided important insights into functional reorganization in subjects with Multiple Sclerosis (MS) at different stage of disease. In this cross-sectional study we first assessed, by means of rs-fMRI, the impact of overall T2 lesion load (T2LL) and MS severity score (MSSS) on resting state networks (RSNs) in 62 relapsing remitting MS (RRMS) patients with mild disability (MSSS < 3). Independent Component Analysis (ICA) followed by dual regression analysis confirmed functional connectivity (FC) alterations of many RSNs in RRMS subjects compared to healthy controls. The anterior default mode network (DMNa) and the superior precuneus network (PNsup) showed the largest areas of decreased FC, while the sensory motor networks area M1 (SMNm1) and the medial visual network (MVN) showed the largest areas of increased FC. In order to better understand the nature of these alterations as well as the mechanisms of functional alterations in MS we proposed a method, based on linear regression, that takes into account FC changes and their correlation with T2LL and MSSS. Depending on the sign of the correlation between FC and T2LL, and furthermore the sign of the correlation with MSSS, we suggested the following possible underlying mechanisms to interpret altered FC: (1) FC reduction driven by MS lesions, (2) "true" functional compensatory mechanism, (3a) functional compensation attempt, (3b) "false" functional compensation, (4a) neurodegeneration, (4b) pre-symptomatic condition (damage precedes MS clinical manifestation). Our data shows areas satisfying 4 of these 6 conditions (i.e., 1,2,3b,4b), supporting the suggestion that increased FC has a complex nature that may exceed the simplistic assumption of an underlying compensatory mechanism attempting to limit the brain damage caused by MS progression. Exploring differences between RRMS subjects with short disease duration (MS_short) and RRMS with similar disability but longer disease duration (MS_long), we found that MS_short and MS_long were characterized by clearly distinct pattern of FC, involving predominantly sensory and cognitive networks respectively. Overall, these results suggest that the analysis of FC alterations in multiple large-scale networks in relation to radiological (T2LL) and clinical (MSSS, disease duration) status may provide new insights into the pathophysiology of relapse onset MS evolution.

Future Brain and Spinal Cord Volumetric Imaging in the Clinic for Monitoring Treatment Response in MS

PURPOSE OF REVIEW

Volumetric analysis of brain imaging has emerged as a standard approach used in clinical research, e.g., in the field of multiple sclerosis (MS), but its application in individual disease course monitoring is still hampered by biological and technical limitations. This review summarizes novel developments in volumetric imaging on the road towards clinical application to eventually monitor treatment response in patients with MS.

RECENT FINDINGS

In addition to the assessment of whole-brain volume changes, recent work was focused on the volumetry of specific compartments and substructures of the central nervous system (CNS) in MS. This included volumetric imaging of the deep brain structures and of the spinal cord white and gray matter. Volume changes of the latter indeed independently correlate with clinical outcome measures especially in progressive MS. Ultrahigh field MRI and quantitative MRI added to this trend by providing a better visualization of small compartments on highly resolving MR images as well as microstructural information. New developments in volumetric imaging have the potential to improve sensitivity as well as specificity in detecting and hence monitoring disease-related CNS volume changes in MS.

Combining clinical and magnetic resonance imaging markers enhances prediction of 12-year employment status in multiple sclerosis patients

BACKGROUND

Multiple sclerosis (MS) is frequently diagnosed in the most productive years of adulthood and is often associated with worsening employment status. However, reliable predictors of employment status change are lacking.

OBJECTIVE

To identify early clinical and brain magnetic resonance imaging (MRI) markers of employment status worsening in MS patients at 12-year follow-up.

METHODS

A total of 145 patients with early relapsing-remitting MS from the original Avonex-Steroids-Azathioprine (ASA) study were included in this prospective, longitudinal, observational cohort study. Cox models were conducted to identify MRI and clinical predictors (at baseline and during the first 12 months) of worsening employment status (patients either (1) working full-time or part-time with no limitations due to MS and retaining this status during the course of the study, or (2) patients working full-time or part-time with no limitations due to MS and switching to being unemployed or working part-time due to MS).

RESULTS

In univariate analysis, brain parenchymal fraction, T1 and T2 lesion volume were the best MRI predictors of worsening employment status over the 12-year follow-up period. MS duration at baseline (hazard ratio (HR) = 1.10, 95% confidence interval (CI) 1.03-1.18; p = 0.040) was the only significant clinical predictor. Having one extra milliliter of T1 lesion volume was associated with a 53% greater risk of worsening employment status (HR = 1.53, 95% CI 1.16-2.02; p = 0.018). A brain parenchymal fraction decrease of 1% increased the risk of worsening employment status by 22% (HR = 0.78, 95% CI 0.65-0.95; p = 0.034).

CONCLUSION

Brain atrophy and lesion load were significant predictors of worsening employment status in MS patients. Using a combination of clinical and MRI markers may improve the early prediction of an employment status change over long-term follow-up.

Cognitive impairment in multiple sclerosis - a review of current knowledge and recent research

Multiple sclerosis (MS) is a chronic, progressive disease of the central nervous system that is characterised by inflammatory damage to the myelin sheath. Though often neglected, cognitive impairment is a common feature of MS that affects 43-70% of patients. It has a sophisticated neuroanatomic and pathophysiologic background and disturbs such vital cognitive domains as speed of information processing, memory, attention, executive functions and visual perceptual functions. In recent years there has been growing interest in neuroimaging findings with regard to cognitive impairment in MS. The possible options of managing cognitive dysfunction in MS are pharmacologic interventions, cognitive rehabilitation and exercise training; however, not enough evidence has been presented in this field. The aim of our article is to provide current knowledge on cognitive impairment in MS based on the most recent scientific results and conclusions with regard to affected cognitive domains, neuropsychological assessment, underlying mechanisms of this disturbance, neuroimaging findings and therapeutic options.

Structural MRI correlates of cognitive function in multiple sclerosis

BACKGROUND

Cognitive impairment (CI) has been associated with numerous magnetic resonance imaging (MRI) indices in multiple sclerosis (MS) patients. In this study we investigated the association of a large set of 2D and 3D MRI markers with cognitive function in MS.

METHODS

A sample of 61 RRMS patients (mean age 41.8 ± 10.6 years old, 44 women, mean disease duration 137.9 ± 83.9 months) along with 51 age and gender matched healthy controls was used in this cross-sectional study. Neuropsychological and other tests, along with a large set of 2D/3D MRI evaluations were made.

RESULTS

44.3% of patients had CI. CI patients had more disability, physical fatigue than non-CI patients and more psychological distress than non-CI patients and HCs. Also, CI patients had significantly larger third ventricle width and volume, smaller coprus callosum index and larger lesion volume than non-CI patients. These MRI markers also significantly predicted cognitive scores after adjusting for age and education, explaining about 30.6% of the variance of the total cognitive score.

CONCLUSIONS

Selected linear and volumetric MRI indices predict cognitive function in MS. Future studies should expand these results by exploring longitudinal changes and producing normative data.

Repetitive Transcranial Magnetic Stimulation, Cognition, and Multiple Sclerosis: An Overview

Multiple sclerosis (MS) affects cognition in the majority of patients. A major aspect of the disease is brain volume loss (BVL), present in all phases and types (relapsing and progressive) of the disease and linked to both motor and cognitive disabilities. Due to the lack of effective pharmacological treatments for cognition, cognitive rehabilitation and other nonpharmacological interventions such as repetitive transcranial magnetic stimulation (rTMS) have recently emerged and their potential role in functional connectivity is studied. With recently developed advanced neuroimaging and neurophysiological techniques, changes related to alterations of the brain's functional connectivity can be detected. In this overview, we focus on the brain's functional reorganization in MS, theoretical and practical aspects of rTMS utilization in humans, and its potential therapeutic role in treating cognitively impaired MS patients.

Efficacy of a Computer-Assisted Cognitive Rehabilitation Intervention in Relapsing-Remitting Multiple Sclerosis Patients: A Multicenter Randomized Controlled Trial

Cognitive impairment is frequently encountered in multiple sclerosis (MS) affecting between 40-65% of individuals, irrespective of disease duration and severity of physical disability. In the present multicenter randomized controlled trial, fifty-eight clinically stable RRMS patients with mild to moderate cognitive impairment and relatively low disability status were randomized to receive either computer-assisted (RehaCom) functional cognitive training with an emphasis on episodic memory, information processing speed/attention, and executive functions for 10 weeks (IG; n = 32) or standard clinical care (CG; n = 26). Outcome measures included a flexible comprehensive neuropsychological battery of tests sensitive to MS patient deficits and feedback regarding personal benefit gained from the intervention on four verbal questions. Only the IG group showed significant improvements in verbal and visuospatial episodic memory, processing speed/attention, and executive functioning from pre - to postassessment. Moreover, the improvement obtained on attention was retained over 6 months providing evidence on the long-term benefits of this intervention. Group by time interactions revealed significant improvements in composite cognitive domain scores in the IG relative to the demographically and clinically matched CG for verbal episodic memory, processing speed, verbal fluency, and attention. Treated patients rated the intervention positively and were more confident about their cognitive abilities following treatment.