Frequency of cognitive impairment dramatically increases during the first 5 years of multiple sclerosis

Cognitive impairment in multiple sclerosis: from phenomenology to neurobiological mechanisms

Multiple sclerosis (MS) is an autoimmune-mediated disease of the central nervous system characterized by inflammation, demyelination and chronic progressive neurodegeneration. Among its broad and unpredictable range of clinical symptoms, cognitive impairment (CI) is a common and disabling feature greatly affecting the patients' quality of life. Its prevalence is 20% up to 88% with a wide variety depending on the phenotype of MS, with highest frequency and severity in primary progressive MS. Involving different cognitive domains, CI is often associated with depression and other neuropsychiatric symptoms, but usually not correlated with motor and other deficits, suggesting different pathophysiological mechanisms. While no specific neuropathological data for CI in MS are available, modern research has provided evidence that it arises from the disease-specific brain alterations. Multimodal neuroimaging, besides structural changes of cortical and deep subcortical gray and white matter, exhibited dysfunction of fronto-parietal, thalamo-hippocampal, default mode and cognition-related networks, disruption of inter-network connections and involvement of the γ-aminobutyric acid (GABA) system. This provided a conceptual framework to explain how aberrant pathophysiological processes, including oxidative stress, mitochondrial dysfunction, autoimmune reactions and disruption of essential signaling pathways predict/cause specific disorders of cognition. CI in MS is related to multi-regional patterns of cerebral disturbances, although its complex pathogenic mechanisms await further elucidation. This article, based on systematic analysis of PubMed, Google Scholar and Cochrane Library, reviews current epidemiological, clinical, neuroimaging and pathogenetic evidence that could aid early identification of CI in MS and inform about new therapeutic targets and strategies.

Altered social cognition in early relapsing remitting multiple sclerosis

INTRODUCTION

People with multiple sclerosis (pwMS) may suffer from some degree of impaired social cognition (SC), the process that integrates the mental operations underlying social interactions. SC is still not clearly characterized in the early stages of MS, and it is not defined whether SC is independent of cognitive impairment.

METHODS

In this cross-sectional study, we aimed to compare SC measures in a population of early (≤5 years) relapsing-remitting MS (RRMS) with an age, sex, and education-matched control group. All participants performed a clinical and a comprehensive neuropsychological assessment. SC evaluation included assessment of facial emotion recognitionn by the Emotion Recognition Task, affective theory of mind (ToM) by the Reading the Mind in the eyes Test (RMET) and cognitive ToM by the Faux Pas test (FPT). Depression, anxiety, fatigue, and quality of life were also assessed. We included 38 pwMS (mean age 34.8 ± 8.7, 78.9% female sex, mean disease duration 1.9±1.3 years) and 38 healthy controls (mean age 34.9 ± 8.4, 81.6% female sex).

RESULTS

Altered social cognition was present in 34.2% of pwMS. Participants with MS performed worse than controls on measures of cognitive ToM, and affective ToM. There were no differences regarding FER. Cognitive ToM and FER correlated with cognitive functions, but no correlation was found between affective ToM and cognitive tests. The only clinical factor associated with altered SC was poor quality of life.

CONCLUSIONS

Social cognition impairment is already present in a significant percentage of early RRMS patients, namely ToM deficits. While cognitive ToM and FER appears to correlate with impaired cognitive results, affective ToM is likely independent of other cognitive functions.

Assessing cognitive changes in multiple sclerosis: criteria for a reliable decision

INTRODUCTION

Quantifying a significant cognitive change on a neuropsychological battery is essential to assess patients' decline or recovery and offer appropriate care. The reliability of change indices is particularly important in multiple sclerosis (MS), as the course of cognitive impairment is quite unpredictable, due at least in part to substantial interindividual variability. The main objective of this study was to compare six different methods for assessing cognitive change in an MS sample: the SD method, two reliable change indices, two standardized regression-based methods (SRB), and the generalized regression-based method (GSRB).

METHOD

One hundred and twenty-three patients with clinically definite MS and 89 healthy controls underwent a battery of standardized neuropsychological tests assessing cognitive functions that are frequently affected in this disease (i.e., verbal episodic memory, working memory, processing speed and verbal fluency).

RESULTS

We observed fairly similar proportions of improvement, decline or stability in the control group whatever the method. By contrast, in the MS sample, regression-based methods with one predictor (i.e., score at T1) and four predictors (i.e., score at T1 and demographic factors: age, sex, education level) detected a significant worsening more often than the reliable change indices while the GSRB method was more consistent with the RCI methods in tasks associated with ceiling effects.

CONCLUSIONS

The interpretation of a patient's cognitive changes depends on which method is used. The (G)SRB methods appear to be relevant indicators for assessing cognitive change in MS. The addition of demographic factors does not seem to play an important role in the prediction of significant worsening in the MS sample, regardless of cognitive domain. For clinicians, an easy-to-use free shiny app is provided.

The TRACK-MS Test Battery: A Very Brief Tool to Track Multiple Sclerosis-Related Cognitive Impairment

Tracking cognition in patients with multiple sclerosis (MS) is important for detection of disease progression but it is often not performed in routine settings due to time constraints. This exploratory cohort study aims to develop a very brief repeatable tracking tool with comparable test quality criteria to the current gold standard, the Brief International Cognitive Assessment for MS (BICAMS). The study included 88 participants (22 healthy controls, 66 MS patients) who were examined at baseline and at one-year follow-up. As a validity criterion for the six administered cognitive tests, we assessed the difference between MS patients and HC, and the correlation with MS-related disability. Combining the two tests with the highest validity-the Controlled Oral Word Association Test and Symbol Digit Modalities Test-yielded an administration time of 5 min. Comparing this new TRACK-MS test battery with the 15 min BICAMS indicated that TRACK-MS showed larger differences between MS patients and healthy controls, a higher correlation with MS-related disability, smaller practice effects, and a good test-retest reliability. We provide evidence that TRACK-MS, although faster to administer, showed at least comparable quality criteria as the BICAMS. As the study was exploratory, replication of these results is necessary.

Altered functional brain states predict cognitive decline 5 years after a clinically isolated syndrome

BACKGROUND

Cognitive impairment occurs in the earliest stages of multiple sclerosis (MS) together with altered functional connectivity (FC).

OBJECTIVE

The aim of this study was to investigate the evolution of dynamic FC states in early MS and their role in shaping cognitive decline.

METHODS

Overall, 32 patients were enrolled after their first neurological episode suggestive of MS and underwent cognitive evaluation and resting-state functional MRI (fMRI) over 5 years. In addition, 28 healthy controls were included at baseline.

RESULTS

Cognitive performance was stable during the first year and declined after 5 years.At baseline, the number of transitions between states was lower in MS compared to controls (p = 0.01). Over time, frequency of high FC states decreased in patients (p = 0.047) and increased in state with low FC (p = 0.035). Cognitive performance at Year 5 was best predicted by the mean connectivity of high FC state at Year 1.

CONCLUSION

Patients with early MS showed reduced functional network dynamics at baseline. Longitudinal changes showed longer time spent in a state of low FC but less time spent and more connectivity disturbance in more integrative states with high within- and between-network FC. Disturbed FC within this more integrative state was predictive of future cognitive decline.

Grey-matter sodium concentration as an individual marker of multiple sclerosis severity

OBJECTIVE

Quantification of brain injury in patients with variable disability despite similar disease duration may be relevant to identify the mechanisms underlying disability in multiple sclerosis (MS). We aimed to compare grey-matter sodium abnormalities (GMSAs), a parameter reflecting neuronal and astrocyte dysfunction, in MS patients with benign multiple sclerosis (BMS) and non-benign multiple sclerosis (NBMS).

METHODS

We identified never-treated BMS patients in our local MS database of 1352 patients. A group with NBMS was identified with same disease duration. All participants underwent ²³Na magnetic resonance imaging (MRI). The existence of GMSA was detected by statistical analysis.

RESULTS

In total, 102 individuals were included (21 BMS, 25 NBMS and 56 controls). GMSA was detected in 10 BMS and 19 NBMS (11/16 relapsing-remitting multiple sclerosis (RRMS) and 8/9 secondary progressive multiple sclerosis (SPMS) patients) (p = 0.05). On logistic regression including the presence or absence of GMSA, thalamic volume, cortical grey-matter volume and T2-weighted lesion load, thalamic volume was independently associated with BMS status (odds ratio (OR) = 0.64 for each unit). Nonetheless, the absence of GMSA was independently associated when excluding patients with significant cognitive alteration (n = 7) from the BMS group (OR = 4.6).

CONCLUSION

Detection of GMSA in individuals and thalamic volume are promising to differentiate BMS from NBMS as compared with cortical or whole grey-matter atrophy and T2-weighted lesions.

Symptom Interconnectivity in Multiple Sclerosis: A Narrative Review of Potential Underlying Biological Disease Processes

Introduction

Fatigue, cognitive impairment, depression, and pain are highly prevalent symptoms in multiple sclerosis (MS). These often co-occur and may be explained by a common etiology. By reviewing existing literature, we aimed to identify potential underlying biological processes implicated in the interconnectivity between these symptoms.

Methods

A literature search was conducted to identify articles reporting research into the biological mechanisms responsible for the manifestation of fatigue, cognitive impairment, depression, and pain in MS. PubMed was used to search for articles published from July 2011 to July 2021. We reviewed and assessed findings from the literature to identify biological processes common to the symptoms of interest.

Results

Of 693 articles identified from the search, 252 were selected following screening of titles and abstracts and assessing reference lists of review articles. Four biological processes linked with two or more of the symptoms of interest were frequently identified from the literature: (1) direct neuroanatomical changes to brain regions linked with symptoms of interest (e.g., thalamic injury associated with cognitive impairment, fatigue, and depression), (2) pro-inflammatory cytokines associated with so-called ‘sickness behavior,’ including manifestation of fatigue, transient cognitive impairment, depression, and pain, (3) dysregulation of monoaminergic pathways leading to depressive symptoms and fatigue, and (4) hyperactivity of the hypothalamic–pituitary-adrenal (HPA) axis as a result of pro-inflammatory cytokines promoting the release of brain noradrenaline, serotonin, and tryptophan, which is associated with symptoms of depression and cognitive impairment.

Conclusion

The co-occurrence of fatigue, cognitive impairment, depression, and pain in MS appears to be associated with a common set of etiological factors, namely neuroanatomical changes, pro-inflammatory cytokines, dysregulation of monoaminergic pathways, and a hyperactive HPA axis. This association of symptoms and biological processes has important implications for disease management strategies and, eventually, could help find a common therapeutic pathway that will impact both inflammation and neuroprotection.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40120-022-00368-2.

Predominant domains and associated demographic and clinical characteristics in multiple sclerosis-related cognitive impairment in mildly disabled patients

Background

Cognitive impairment (CI) is a common finding in multiple sclerosis (MS); however, there is a limited information about its prevalence in mildly disabled cases. We aimed to determine the most affected domains, and also the relation between the demographic factors and cognitive outcomes in mildly disabled relapsing–remitting MS (RRMS).

Results

Ninety-one mildly disabled RRMS patients with expanded disability status scale (EDSS) < 4 and literacy level above 9 years, were recruited. Based on Minimal Assessment of Cognitive Function in MS (MACFIMS) battery, CI was observed in 19.8% of the patients while 40.60% of the patients had at least one failure in cognitive tests. The most common impaired cognitive domain was information processing speed and working memory (27.5%). There was no significant difference between men and women in terms of CI in our sample (p-values > 0.05). Disease duration (p = 0.01), EDSS (p = 0.01), and education (p < 0.01) were significantly different between CI and non-CI patients, while age (p = 0.72), sex (p = 0.50), diagnostic gap (p = 0.89), and frequency of relapses (p = 0.22), did not differ considerably.

Conclusions

RRMS patients experience some degrees of CI that may present even before the onset of remarkable physical disability; nevertheless, a higher EDSS score and longer disease duration increases the risk of CI. These findings suggest routine cognitive assessment of MS patients.

Medicolegal Implications of Mild Neurocognitive Disorder

INTRODUCTION

The syndromes of mild cognitive impairment (MCI) or mild neurocognitive disorder (MiND), often prodromal to dementia (Major Neurocognitive Disorder), are characterized by acquired clinically significant changes in one or more cognitive domains despite preserved independence. Mild impairment has significant medicolegal consequences for an affected person and their care system. We review the more common etiologies of MiND and provide a systematic review of its medicolegal implications.

METHODS

We conducted a systematic review of the peer-reviewed English literature on medicolegal aspects of MCI or MiND using comprehensive search terms and expanding our review to include sources cited by these reports.

RESULTS

Impairment of memory, executive function, social cognition, judgment, insight or abstraction can alter an individual's abilities in a variety of areas that include decision making, informed consent, designation of a surrogate decision-maker such as a health care proxy, understanding and management of financial affairs, execution of a will, or safe driving.

CONCLUSION

Even mild cognitive impairment can have significant behavioral consequences. Clinicians can assist care partners and persons with MCI or MiND by alerting them to the medicolegal concerns that often accompany cognitive decline. Early recognition and discussion can help a care system manage medicolegal risk more effectively and promote thoughtful advance planning.

[Supporting the adaptation to the announcement of multiple sclerosis]

Multiple sclerosis (MS) is a disease that most often begins in young adulthood. With at least 2,500 new cases diagnosed each year in France, it is the leading cause of severe non-traumatic disability among young adults. The announcement of MS constitutes a brutal intrusion into the life of the subject. The carers accompany the process of cognitive and emotional adjustment that is inevitable in order to learn to live with the disease.

Cognitive recovery in people with relapsing/remitting multiple sclerosis: A randomized clinical trial on virtual reality-based neurorehabilitation

BACKGROUND

Multiple sclerosis (MS) can adversely affect several domains of cognitive function, including attention, information processing, memory and learning, executive functions and visuospatial skills. In recent years, technological innovations have proven effective in improving motor and cognitive impairment in neurological patients, including those affected by MS.

OBJECTIVE

The study aims to evaluate cognitive outcomes after rehabilitation training with the Virtual Reality rehabilitation system (VRRS) in patients suffering from MS.

METHODS

All patients were randomized into either the control group (CG: 15 patients) receiving conventional cognitive rehab or the experimental group (EG) using virtual reality (VR) (15 patients). Both groups underwent the same amount of cognitive training, 3 times a week for 8 weeks. They were submitted to neuropsychological assessment before (T0) and after the rehabilitation treatment (T1).

RESULTS

Our data showed that both conventional and VR cognitive rehabilitation approaches improved mood (p < 0.001) and visuospatial skills. However, only in the EG a significant improvement in specific cognitive domains (p < 0.001), including learning ability, short-term verbal memory, lexical access ability, as well as quality of life related to mental states, was found.

CONCLUSIONS

The present study demonstrated that VR can be a motivational and effective tool for cognitive recovery in MS patients.

Neurocognitive impairment and social cognition in multiple sclerosis

PURPOSE/AIM OF THE STUDY

The impairment of neurocognitive functions occurs in all subtypes of multiple sclerosis, even from the earliest stages of the disease. Commonly reported manifestations of cognitive impairment include deficits in attention, conceptual reasoning, processing efficiency, information processing speed, memory (episodic and working), verbal fluency (language), and executive functions. Multiple sclerosis patients also suffer from social cognition impairment, which affects their social functioning. The objective of the current paper is to assess the effect of neurocognitive impairment and its potential correlation with social cognition performance and impairment in multiple sclerosis patients.

MATERIALS AND METHODS

An overview of the available-to-date literature on neurocognitive impairment and social cognition performance in multiple sclerosis patients by disease subtype was performed.

RESULTS

It is not clear if social cognition impairment occurs independently or secondarily to neurocognitive impairment. There are associations of variable strengths between neurocognitive and social cognition deficits and their neural basis is increasingly investigated.

CONCLUSIONS

The prompt detection of neurocognitive predictors of social cognition impairment that may be applicable to all multiple sclerosis subtypes and intervention are crucial to prevent further neural and social cognition decline in multiple sclerosis patients.

Identifying Early Neuropsychological Indicators of Cognitive Involvement in Multiple Sclerosis

Multiple sclerosis (MS) is a debilitating disease of the central nervous system that is most commonly seen in early to middle adulthood, although it can be diagnosed during childhood or later in life. While cognitive impairment can become more prevalent and severe as the disease progresses, signs of cognitive involvement can be apparent in the early stages of the disease. In this review, we discuss the prevalence and types of cognitive impairment seen in early MS, including the specific measures used to identify them, as well as the challenges in characterizing their frequency and progression. In addition to examining the progression of early cognitive involvement over time, we explore the clinical factors associated with early cognitive involvement, including demographics, level of physical disability, disease modifying therapy use, vocational status, and psychological and physical symptoms. Given the prevalence and functional impact these impairments can have for persons with MS, considerations for clinicians are provided, such as the role of early cognitive screenings and the importance of comprehensive neuropsychological assessments.

Structural constraints of functional connectivity drive cognitive impairment in the early stages of multiple sclerosis

BACKGROUND

The relationship between structural and functional deficits in multiple sclerosis (MS) is unclear.

OBJECTIVE

This study explored structure-function relationships during the 5 years following a clinically isolated syndrome and their role in cognitive performance.

METHODS

Thirty-two patients were enrolled after their first neurological episode suggestive of MS and followed for 5 years, along with 10 matched healthy controls. We assessed structural (using diffusion tensor imaging) and functional (using resting-state functional magnetic resonance imaging (fMRI)) brain network metrics, clinical and cognitive scores at each follow-up visit. Structural-functional coupling, calculated as the correlation coefficient between strengths of structural and functional networks, was used to assess structure-function relationships.

RESULTS

Structural clustering coefficient was significantly increased after 5 years, whereas characteristic path length decreased. Structural connections decreased after 1 year and increased after 5 years. Functional connections and related path lengths were decreased after 5 years. Structural-functional coupling had increased significantly after 5 years. This structural-functional coupling was associated with cognitive and clinical evolution, with stronger coupling associated with a decline in both domains.

CONCLUSION

Our findings provide novel biological evidence that MS leads to a more constrained anatomical-dependant functional connectivity. The collapse of this network seems to lead to both cognitive worsening and clinical disability.

Time matters: Early-phase multiple sclerosis is accompanied by considerable impairments across multiple domains

Impairments across multiple domains are a disabling consequence of multiple sclerosis (MS). Originating from preventive medical strategies, the “time matters”-perspective has become a focal point when treating MS. In particular, early detection of physical and cognitive deficits, along with deficits in patient-reported outcomes seems crucial to further optimize both pharmacological and non-pharmacological MS treatment strategies. Therefore, this topical review investigates the level of impairments across multiple domains (physical function, cognitive function, and patient-reported outcomes) in the early stage of MS (⩽5 years since diagnosis, including clinically isolated syndrome (CIS)), when compared to matched healthy controls. Even at early disease stages, studies show impairments corresponding to 8%–34% and small-to-large numerical effect sizes (0.35–2.85) in MS/CIS patients across domains. This evidence call for early screening programs along with early interventions targeting the multiple impaired domains. This further highlights the importance of preventive initiatives preserving and/or restoring physical and cognitive reserve capacity if possible.

Cognitive Dysfunction in the Early Stages of Multiple Sclerosis-How Much and How Important?

Purpose of Review

Multiple sclerosis (MS) is a demyelinating disease of the central nervous system that mainly affects young adults and that is one of the leading causes of disability in this age group, with cognitive impairment occurring early in the course of the disease. This article summarizes the current knowledge about cognitive dysfunction in the early phase of MS, including biomarkers, MRI correlates, and its value as a prognostic marker.

Recent Findings

New sets of neuropsychological tests have been established to screen for cognitive dysfunction more easily and accurately. Moreover, structural changes detected by brain MRI and several biomarkers found in cerebrospinal fluid and blood serum have been recently correlated with decreased cognitive performance. Additionally, factors influencing cognition in MS, such as disease-modifying therapy, mood disorders, and lifestyle, are better described.

Summary

Cognitive impairment early in the course of MS is suggested as a prognostic factor for disease progression. However, clear-cut definitions of the early stage of MS as well as unified criteria for the diagnosis of cognitive impairment are still lacking. New and more reliable tools for evaluating cognition in MS patients should be developed and introduced into everyday practice to facilitate the implementation of effective disease-modifying therapy, cognitive rehabilitation, and lifestyle management.

Neuropsychiatric Symptoms of Multiple Sclerosis: State of the Art

Multiple Sclerosis (MS) is a chronic disabling neuroinflammatory disease. Psychiatric manifestations have a high prevalence in MS patients and may worsen the illness progression and the patients' quality of life (QoL). Depression is a highly prevalent condition in MS patients, associated with poorer adherence to treatment, decreased functional status and QoL, and increased suicide risk. Diagnosis and treatment of this disorder is challenging because of symptom overlap. Other prevalent psychiatric comorbidities are anxiety disorders, bipolar disorder, psychotic disorders, substance misuse and personality disorders. As the illness progresses, personality changes can happen, as well as affect abnormalities. Cognitive changes occur frequently in MS patients, and affect features like processing speed, attention, learning, memory, visual spatial capabilities, and some language deficits. Disease-modifying treatments may reduce cognitive impairment because of their container action on the brain's lesion burden. Other QoL determinants such as fatigue, pain, sexual dysfunction, exercise, resilience and social support should be taken into account, in order to promote the individuals' well-being. Further studies are needed in order to elucidate the effectiveness of pharmacotherapy and more neuroimaging studies are required to clarify the relationship between structural changes and psychiatric comorbidities.

Resolving the cognitive clinico-radiological paradox - Microstructural degeneration of fronto-striatal-thalamic loops in early active multiple sclerosis

BACKGROUND

Associations between cognitive impairment (CI) and both global and regional brain volumes can be weak in early multiple sclerosis (MS), a dilemma known as cognitive clinico-radiological paradox. We hypothesized that white-matter (WM) integrity within fronto-striatal-thalamic networks may be a sensitive marker for impaired performance in speed-dependent tasks, typical for early MS.

METHODS

Twenty-seven patients with early active relapsing-remitting MS (RRMS) received comprehensive neuropsychological assessment and underwent structural and diffusion-weighted brain magnetic resonance imaging (MRI). Global and regional brain volumes were obtained using FreeSurfer software. Fractional anisotropy (FA) was computed from diffusion tensor images to assess microstructural alterations within three anatomically predefined fronto-striatal-thalamic loops known to be relevant for speed-dependent attention and executive functions.

RESULTS

Overall cognitive performance (Spearman's ρ = .51) and performance in the domains processing speed (ρ = .44) and executive functions (ρ = .41) were correlated with patients' mean FA within the right dorsolateral-prefrontal loop. In addition, overall cognitive performance correlated with mean FA within the right lateral orbitofrontal loop (ρ = .39) - but only before controlling for WM lesion count. In contrast, regional volumes of grey-matter structures within these fronto-striatal-thalamic loops (including the thalamus) were not significantly related to CI. The total brain volume was associated with performance in the domain verbal memory (ρ = .43) only.

CONCLUSIONS

Microstructural degeneration within specific fronto-striatal-thalamic WM networks, previously characterized as crucial for task-monitoring, better accounts for speed-dependent CI in patients with early active RRMS than global or regional brain volumes. Our findings may advance our understanding of the neural substrates underlying CI characteristic for early RRMS.

Do people with multiple sclerosis benefit from PC-based neurorehabilitation? A pilot study

Multiple Sclerosis (MS) is an inflammatory degenerative disease of the central nervous system. Cognitive impairment is a frequent feature of MS at both the earlier and later stages of the disease, and it tends to worsen over time. Cognitive rehabilitation (CR) is becoming a standard component of neurorehabilitation in patients with MS. The aim of this study is to evaluate the effect of computerized CR, by using the Italian software ERICA, on cognitive and daily life performance in MS patients with mild to moderate cognitive impairment. We studied 40 individuals affected by MS, randomized into either traditional CR group (TCRG: n = 20), which performed a conventional cognitive training, or the computer-assisted CR group (CCRG: n = 20), which performed PC-based CR. The cognitive dysfunctions were investigated through a complete neuropsychological battery, administered before (T0) and after (T1) each different training. Both the trainings were well-tolerated and led to improvement in cognitive function. Notably, the CCRG had a significant effect in improving memory, attention, and processing speed, as compared to TCRG. ERICA training could be a valuable tool for the CR in patients affected by MS. Further studied are needed to confirm these promising results and evaluate the long-term effects.

Identifying risk factors for cognitive issues in multiple sclerosis

INTRODUCTION

Cognitive impairment (CI) in Multiple Sclerosis (MS) has progressively regained clinical and research interest and is currently recognized as a debilitating and burdensome problem for these patients. Studying risk and protecting factors that may influence the development and course of CI is currently an area of increasing interest, due to the potential for preventive strategies. Areas covered: In this narrative review the authors briefly addressed the physiopathologic basis, assessment and management of CI in MS and then focused on identifying modifiable and not modifiable risk factors for CI in MS, providing an overview of the current knowledge in the field and indicating avenues for future research. Expert opinion: Improving our understanding of potentially modifiable environmental and lifestyle risk factors or protective factors for CI is important in order to prompt preventive strategies and orient patient counselling and clinical management. To this aim, we need to enhance the current level of evidence linking lifestyle factors to cognition and evaluate some factors that were only preliminary addressed in research. Moreover, we need to explore the role of each factor into the subject cognitive outcome, next to the possible interactions between different environmental factors as well as between environmental and genetic factors.

Differentiation of Cognitive Deficit Profiles in Multiple Sclerosis Patients: Latent Profile Analysis

OBJECTIVE

The purpose of this study was to ascertain whether the application of the Audio Recorded Cognitive Screen (ARCS) in cognitive functioning screening of persons with multiple sclerosis (MS) differentiates profiles of existing cognitive deficits (CDs) and whether this instrument can discriminate accurately between subjects who are cognitively intact (CI) and those with a cognitive disorder.

SUBJECTS AND METHODS

The research was conducted on a sample of 359 subjects, with two subsets of participants: 108 persons with a relapsing-remitting form of MS and 251 persons from the general population.

RESULTS

We labeled the three profiles obtained by applying the ARCS questionnaire: the CI profile, the profile of CI with visuospatial difficulties, and the profile of persons with CD.

CONCLUSION

ARCS has the ability to differentiate persons with a CD from those without, both in a sample of persons suffering from MS and in a sample of persons from the general population. This finding indicates that this instrument is well suited for profiling the cognitive status into specific categories, which puts it among the instruments with a wide range of implementation.

Can we predict cognitive decline after initial diagnosis of multiple sclerosis? Results from the German National early MS cohort (KKNMS)

BACKGROUND

Cognitive impairment (CI) affects approximately one-third of the patients with early multiple sclerosis (MS) and clinically isolated syndrome (CIS). Little is known about factors predicting CI and progression after initial diagnosis.

METHODS

Neuropsychological screening data from baseline and 1-year follow-up of a prospective multicenter cohort study (NationMS) involving 1123 patients with newly diagnosed MS or CIS were analyzed. Employing linear multilevel models, we investigated whether demographic, clinical and conventional MRI markers at baseline were predictive for CI and longitudinal cognitive changes.

RESULTS

At baseline, 22% of patients had CI (impairment in ≥2 cognitive domains) with highest frequencies and severity in processing speed and executive functions. Demographics (fewer years of academic education, higher age, male sex), clinical (EDSS, depressive symptoms) but no conventional MRI characteristics were linked to baseline CI. At follow-up, only 14% of patients showed CI suggesting effects of retesting. Neither baseline characteristics nor initiation of treatment between baseline and follow-up was able to predict cognitive changes within the follow-up period of 1 year.

CONCLUSIONS

Identification of risk factors for short-term cognitive change in newly diagnosed MS or CIS is insufficient using only demographic, clinical and conventional MRI data. Change-sensitive, re-test reliable cognitive tests and more sophisticated predictors need to be employed in future clinical trials and cohort studies of early-stage MS to improve prediction.

Alemtuzumab Improves Cognitive Processing Speed in Active Multiple Sclerosis-A Longitudinal Observational Study

Background

Several disease-modifying drugs have shown promising effects on cognitive impairment in multiple sclerosis (MS). Alemtuzumab, a humanized monoclonal antibody, is effective in controlling disease activity, however, has not been evaluated for its effects on cognition in detail so far.

Objective

To explore the influence of alemtuzumab on cognitive impairment in active relapsing–remitting MS (RRMS) as well as possible clinical and neuroimaging predictors of cognitive changes during the first year of therapy.

Methods

Extensive neuropsychological assessment was administered to 21 patients with active RRMS at baseline and again after the second treatment with alemtuzumab (mean time span: 15.05 months). Clinical and routine structural neuroimaging markers were explored for their capacity to predict individual courses of cognitive change.

Results

Overall cognitive functioning remained stable or improved during the observational period of alemtuzumab treatment on average. Scores on two neuropsychological tests of processing speed significantly improved and clinically relevant individual gains of processing speed were seen in the majority of patients. Linear regression models showed that clinical and routine neuroimaging measures of disease activity could not fully account for these cognitive changes.

Conclusion

Results suggest that alemtuzumab treatment in active RRMS stabilizes overall cognitive functioning and furthermore positively affects cognitive processing speed. Changes in processing speed were independent from clinical and structural neuroimaging parameters of disease activity and may thus represent an underrated and independent outcome measure to evaluate treatment effects.

Imaging markers of multiple sclerosis prognosis

PURPOSE OF REVIEW

Studies of large longitudinal cohorts of patients with multiple sclerosis (MS) have emphasized the prognostic value of conventional MRI markers, at least during early stages. Advanced imaging metrics derived from quantitative MRI and PET provide relevant information about microstructural damage within and outside visible lesions that may be more sensitive to predict long-term disability. Here, we summarize the most recent findings regarding the prognostic value of imaging markers throughout MS stages.

RECENT FINDINGS

In clinically isolated syndrome, the presence of at least one brain or spinal cord T2 lesion strongly increases the risk of conversion to clinically definite MS (hazard ratio ranging from 5 to 11). Similarly, the occurrence of new white matter lesions is strongly predictive of subsequent relapse rate and response to current disease modifying therapies. Beyond white matter lesions, volumetric changes in the grey matter and normal-appearing tissue damage are more sensitive prognostic markers for physical and cognitive disability, especially in progressive MS.

SUMMARY

Although white matter lesion number and volume still remains the imaging metric used in daily clinical practice, further development of advanced imaging predictors of long-term disability should allow a better stratification of patients in future clinical trials aimed at promoting repair or neuroprotection.

New brain lesions with no impact on physical disability can impact cognition in early multiple sclerosis: A ten-year longitudinal study

OBJECTIVE

In early multiple sclerosis, although brain T2 lesions accrual are hallmark of the disease, only weak correlations were found between T2 lesions accrual and EDSS progression, the disability scale commonly used in multiple sclerosis studies. This may be related to the very poor sensitivity of EDSS to cognitive dysfunctions that may occur and progress from the first stage of the disease. In the present study, we aimed to demonstrate that cognitive deficits progress during the first ten years of MS and are significantly impacted by new T2 lesions.

METHODS

EDSS and extensive neuropsychological battery (22 measures) exploring memory, attention/speed of information processing and executive functions were assessed at baseline, Year 1 and Year 10 in 26 patients enrolled after their first clinical attack. To limit the bias of test-retest effect, only measures obtained at Year 1 and Year 10 were reported in the analysis. Raw scores of patients were transformed into z-scores using published normative data when available or scores of matched controls. Lesion probability mapping was used to assess the potential relationships between T2 lesions accumulation, cognitive decline and EDSS progression (P<0.05, FWE-corrected).

RESULTS

At Year 1, 27% of patients showed attention/speed of information processing deficits, 11.5% executive dysfunction and 11.5% memory impairment. During the follow-up, frequency and severity of executive dysfunction increased (from 11.5% of patients at Year 1 to 42% at Year 10, p<0.01) while no significant changes were evidenced for the other cognitive domains. Median EDSS increased from 0.5 [range: 0-3] at Year 1 to 2.5 [range: 0-6.5] at Year 10 (p<0.001). During the ten-year follow-up, lesions accumulation in the left cerebellum and semi-ovale centers was associated with EDSS progression. In contrast, most lesions accumulation in the frontal, parietal and temporal lobes were associated with cognitive decline but had no effect on EDSS progression.

CONCLUSION

The present study provides strong evidence that clinically silent T2 lesions impact cognition in early MS. In daily practice, early prevention of T2 lesions accrual may be useful to limit cognitive decline.

Can fibrinolytic system components explain cognitive impairment in multiple sclerosis?

BACKGROUND

The fibrinolytic system is capable of modulating inflammatory and degenerative events within the central nervous system. Specifically, the plasminogen activator inhibitor-1 (PAI-1) has been associated with different pathological conditions in multiple sclerosis (MS) and its role in cognitive functioning is also known.

OBJECTIVES AND METHODS

To study the association between plasma levels and the polymorphic variants of the PAI-1 gene and cognitive performance in MS. 176 patients were studied. Neuropsychological evaluation was performed with the Brief Repeatable Battery of Neuropsychological Tests (BRB-N). A Polymerase Chain Reaction (PCR) was used to determine PAI-1 4G/5G polymorphisms and quantification was performed using an Enzyme-Linked ImmunoSorbent Assay (ELISA).

RESULTS

Participants were categorized as not cognitively impaired (NCI; n=114) and cognitively impaired (CI; n=62). The NCI group had a higher percentage of heterozygous subjects but no statistical differences were found between the CI and NCI group. Neuropsychological functioning did not correlate with plasma levels of PAI-1 or its genetic polymorphism. It is noteworthy that PAI-1 plasma levels were related to neurological impairment.

DISCUSSION

Cognitive impairment in MS is due to strategic focal lesions affecting regions and tracts involved in cognitive processes and to diffuse damage in the white and gray matter. This complex etiology could explain the absence of a relationship between the cognitive functioning and PAI-1 in patients with MS that has been found in vascular dementia or Alzheimer's disease. Plasma curves of PAI-1 and its measures in cerebrospinal fluid could help elucidate the role of PAI-1 in MS.

Efficacy of a short cognitive training program in patients with multiple sclerosis

BACKGROUND

Cognitive impairment is a common feature in multiple sclerosis (MS) and may have a substantial impact on quality of life. Evidence about the effectiveness of neuropsychological rehabilitation is still limited, but current data suggest that computer-assisted cognitive training improves cognitive performance.

OBJECTIVE

The objective of this study was to evaluate the efficacy of combined computer-assisted training supported by home-based neuropsychological training to improve attention, processing speed, memory and executive functions during 3 consecutive months.

METHODS

In this randomized controlled study blinded for the evaluators, 62 MS patients with clinically stable disease and mild-to-moderate levels of cognitive impairment were randomized to receive a computer-assisted neuropsychological training program (n=30) or no intervention (control group [CG]; n=32). The cognitive assessment included the Brief Repeatable Battery of Neuropsychological Test. Other secondary measures included subjective cognitive impairment, anxiety and depression, fatigue and quality of life measures.

RESULTS

The treatment group (TG) showed significant improvements in measures of verbal memory, working memory and phonetic fluency after intervention, and repeated measures analysis of covariance revealed a positive effect in most of the functions. The control group (CG) did not show changes. The TG showed a significant reduction in anxiety symptoms and significant improvement in quality of life. There were no improvements in fatigue levels and depressive symptoms.

CONCLUSION

Cognitive intervention with a computer-assisted training supported by home training between face-to-face sessions is a useful tool to treat patients with MS and improve functions such as verbal memory, working memory and phonetic fluency.

Increased total sodium concentration in gray matter better explains cognition than atrophy in MS

OBJECTIVE

To investigate whether brain total sodium accumulation assessed by ²³Na MRI is associated with cognitive deficit in relapsing-remitting multiple sclerosis (RRMS).

METHODS

Eighty-nine participants were enrolled in the study (58 patients with RRMS with a disease duration ≤10 years and 31 matched healthy controls). Patients were classified as cognitively impaired if they failed at least 2 tasks on the Brief Repeatable Battery. MRI was performed at 3T using ²³Na MRI to obtain total sodium concentration (TSC) in the different brain compartments (lesions, normal-appearing white matter [NAWM], gray matter [GM]) and ¹H- magnetization-prepared rapid gradient echo to assess GM atrophy (GM fraction).

RESULTS

The mean disease duration was 3.1 years and the median Expanded Disability Status Scale score was 1 (range 0-4.5). Thirty-seven patients were classified as cognitively preserved and 21 as cognitively impaired. TSC was increased in GM and NAWM in cognitively impaired patients compared to cognitively preserved patients and healthy controls. Voxel-wise analysis demonstrated that sodium accumulation was mainly located in the neocortex in cognitively impaired patients. Regression analysis evidenced than the 2 best independent predictors of cognitive impairment were GM TSC and age. Receiver operating characteristic analyses demonstrated that sensitivity and specificity of the GM TSC to classify patients according to their cognitive status were 76% and 71%, respectively.

CONCLUSIONS

This study provides 2 main findings. (1) In RRMS, total sodium accumulation in the GM is better associated with cognitive impairment than GM atrophy; and (2) total sodium accumulation in patients with cognitive impairment is mainly located in the neocortex.

Cognition and fatigue in patients with relapsing multiple sclerosis treated by subcutaneous interferon β-1a: an observational study SKORE

BACKGROUND

Multiple sclerosis (MS) is a chronic autoimmune disease of the central nervous system, which often causes progressive neurological disability. In addition to motor and sensory dysfunction, cognitive decline and fatigue are frequent manifestations of the disease. Fatigue is probably the most common symptom, with up to 90% of MS individuals reporting fatigue at some point. Cognitive impairment affects about 50% of patients and may be present at all MS stages. The aim of this observational study was to evaluate changes in cognition, fatigue, and disability status in 300 relapsing-remitting MS (RRMS) patients, treated with subcutaneous (sc) interferon (IFN) β-1a over 2 years.

METHODS

The study was designed as an observational, multicentre, prospective, single-arm, phase IV study carried out in 13 MS centres in the Czech Republic. Cognition status was assessed using the Paced Auditory Serial Addition Task (PASAT), fatigue using the Fatigue Descriptive Scale (FDS), and disability using the Expanded Disability Status Scale (EDSS), at baseline, and after 6, 12 and 24 months. The percentage of patients with changed versus stable cognition, fatigue status and disability was calculated at each time point and the changes in these scores were evaluated.

RESULTS

The proportion of patients with cognitive improvement was higher compared with those with a stable or decreased PASAT scores at all time points, and the average cognitive performance improved during the follow-up period. Also the proportion of patients with stable or improved fatigue and EDSS scores was higher compared with those in which FDS or EDSS scores declined, this was found at all time points of the analysed sample. However, the direct effect of IFN β-1a on cognition and fatigue cannot be concluded from this study.

CONCLUSIONS

The results of this observational study have demonstrated a stable or improved cognitive performance, fatigue status, and disability level in the majority of RRMS patients treated with sc IFN β-1a over a two-year follow-up period, in a real life setting, in the Czech Republic.

Low Prevalence of Sleep Disorders in Demyelinating Disease in a Northern Tenerife Population

STUDY OBJECTIVES

Sleep disorders are seen in patients with demyelinating disease (DD) more often than in the general population. Combination of physical and psychological factors such as pain, spasms, nocturia, depression, anxiety, or medication effects could contribute to sleep disruption. Frequently, these disturbances have a major impact on health and quality of life of patients. The aim of this study was to estimate the prevalence of sleep disorders in patients seen in the DD consultation.

METHODS

240 patients; mean age 43 years, 187 women; 163 patients with multiple sclerosis (MS): 144 relapsing-remitting, 19 progressive forms, 36 clinically isolated syndrome, 26 radiological isolated syndrome, and 15 patients with others DD. All participants completed questionnaires: Pittsburgh, Epworth, and Stanford scales, indirect symptoms of RLS and Obstructive Sleep Apnea, Fatigue Severity Scale, and Multiple Sclerosis Quality of Life-54.

RESULTS

Moderate/severe insomnia 12.5%, OSA 5.8%, RLS 9.6% (confirmed 3 cases), narcolepsy 0, fatigue (> 4) 24.6%. Physical QoL 66.6 ± 19.6, Mental QoL 66.1 ± 21.9. Patients with an established diagnosis showed higher scores on insomnia compared to the group of CIS and RIS (F = 3.85; p = 0.023), no differences were in the other parameters. Fatigue showed high correlation with insomnia (r = 0.443; p < 0.001), RLS (r = 0.513; p < 0.001), and sleepiness (r = 0.211; p = 0.001). None of the variables included in the regression model were shown to be predictors of Physical and Mental QoL.

CONCLUSIONS

A high percentage of our sample sleeps well. Emphasize the low prevalence of sleep disorders (insomnia, fatigue, RLS, etc). We detected an overestimation in the RLS questionnaire and the low QoL recorded.

Cognitive status in patients with multiple sclerosis in Lanzarote

OBJECTIVES

Cognitive impairment is a common feature in multiple sclerosis affecting ~43%-72% of patients, which involves cognitive functions such as memory, processing speed, attention, and executive function. The aim of this study was to describe the extent and pattern of the involvement of cognitive impairment and psychological status in all patients with multiple sclerosis on a small Spanish island.

PATIENTS AND METHODS

In all, 70 patients and 56 healthy controls were included in the study between February 2013 and May 2013. All participants were assessed using the Brief Repeatable Battery of Neuropsychological Test. The patients also completed instruments to evaluate the presence of fatigue, perceived cognitive dysfunction, and symptoms of anxiety and depression. All procedures were performed in a single session.

RESULTS

Cognitive impairment, defined as a score <1.5 standard deviation on two subtests of the battery, was present in 35% of the participants. The most frequently affected domain was working memory, followed by verbal memory and processing speed. Disease duration showed a moderate correlation with visuospatial memory and processing speed. The Expanded Disability Status Scale score correlated with verbal and processing speed. Verbal memory was correlated with depression symptoms and fatigue.

CONCLUSION

Cognitive impairment was present in 35% of the study population. The most affected domains were working memory and verbal memory. Working memory and verbal fluency deficit are independent factors of disease evolution. Cognitive decline is related to clinical variables and psychological measures such as fatigue or depression but not to anxiety.

Optimizing the initial choice and timing of therapy in relapsing-remitting multiple sclerosis

With 12 available US Food and Drug Administration approved medications for the treatment of relapsing multiple sclerosis (MS), choosing an initial therapy is no longer a straightforward task. Each disease-modifying therapy (DMT) has a distinct risk-benefit profile and each patient is an individual. Therefore, the development of a simple algorithm to apply in selecting initial therapy is not feasible. Instead, the prescribing physician must consider many factors related to the treatments themselves, such as efficacy, safety, and tolerability, while also taking into account a particular patient's disease characteristics, personal preferences, comorbid illnesses and reproductive plans. The efficacy of each drug may be assessed through clinical trial data, although these data are limited by scarcity of direct comparisons among the different agents and lack of availability of biomarkers to predict an individual patient's response. Differences in safety profiles help to distinguish the various DMTs and influence selection of agent; both the known safety concerns, which can be addressed with risk mitigation and monitoring strategies, and the potential for yet undiscovered safety issues must be assessed, and an individual patient's comfort level with the risks and ability to comply with monitoring must be determined. Potential issues related to tolerability, which largely relate to matters of patient personal preference and lifestyle, should also be factored into the decision-making process. With regard to the timing of therapy initiation, it must be acknowledged that long-term benefits of early DMT have not yet been definitively demonstrated. Nonetheless, starting DMT early in the MS disease course has been shown to have a beneficial effect on relapse prevention, and appears to curtail the atrophy and neurodegenerative changes that are now known to begin at disease onset. Although under certain circumstances there are acceptable reasons for deferring treatment, it is generally recommended that DMT is initiated early in the disease course.

Symptomatic management in multiple sclerosis

Multiple sclerosis (MS) is the commonest cause of disability in young adults. While there is increasing choice and better treatments available for delaying disease progression, there are still, very few, effective symptomatic treatments. For many patients such as those with primary progressive MS (PPMS) and those that inevitably become secondary progressive, symptom management is the only treatment available. MS related symptoms are complex, interrelated, and can be interdependent. It requires good understanding of the condition, a holistic multidisciplinary approach, and above all, patient education and empowerment.

Neurophysiological Evidence of Compensatory Brain Mechanisms in Early-Stage Multiple Sclerosis

Multiple sclerosis (MS) is a chronic central nervous system disorder characterized by white matter inflammation, demyelination and neurodegeneration. Although cognitive dysfunction is a common manifestation, it may go unnoticed in recently-diagnosed patients. Prior studies suggest MS patients develop compensatory mechanisms potentially involving enhanced performance monitoring. Here we assessed the performance monitoring system in early-stage MS patients using the error-related negativity (ERN), an event-related brain potential (ERP) observed following behavioral errors. Twenty-seven early-stage MS patients and 31 controls were neuropsychologically assessed. Electroencephalography recordings were obtained while participants performed: a) a stop task and b) an auditory oddball task. Behavior and ERP measures were assessed. No differences in performance were found between groups in most neuropsychological tests or in behavior or ERP components in the auditory oddball task. However, the amplitude of the ERN associated with stop errors in the stop task was significantly higher in patients. ERN amplitude correlated positively with scores on the Expanded Disability Status Scale and the Multiple Sclerosis Severity Score, and negatively with the time since last relapse. Patients showed higher neuronal recruitment in tasks involving performance monitoring. Results suggest the development of compensatory brain mechanisms in early-stage MS and reflect the sensitivity of the ERN to detect these changes.

Prevalence and incidence of cognitive impairment in multiple sclerosis: a population-based survey in Catania, Sicily

Cognitive impairment (CIm) is a frequent finding in multiple sclerosis (MS) affecting up to 65% of patients. The aim of this study was to evaluate the prevalence and incidence of CIm in a population-based cohort of MS patients identified in the city of Catania from 1995 to 2004. One-hundred and twenty-five patients experiencing the onset of MS during 1995-2004 were enrolled. Cognitive performance was assessed through the Brief Repeatable Battery (BRB) of neuropsychological tests and the Stroop word-color task (ST). CIm was defined as the failure on at least three tests involving at least two different domains. Patients without CIm at baseline were followed up after over 3 years. The most impaired tests were the Symbol Digit Modalities Test (36%) and the Paced Auditory Serial Addition Test 3 (35%). At baseline the prevalence of CIm was 44% (95% CI 35.2-53.1). An almost sixfold increased risk of developing CIm was found among MS patients aged 40 and above at the time of the NPS examination (OR 5.84; 95% CI 2.57-13.2; p value <0.0001) and a threefold increased risk for patients with an EDSS score >3 (OR 3.51; 95% CI 1.30-9.46, p value 0.01). At the follow-up out of the 70 MS patients without CIm at baseline evaluation, 26 (37.1 %) developed CIm. The total person-years at risk was 269 person-years giving an incidence rate of CIm of 96.6/1,000 person-year (95% CI 57.3-128.7). The overall prevalence of CIm in MS is 44% and the incidence after 4 years is 37.1%. CIm affects more frequently patients older than 40 years and with a higher EDSS score.

School performance as a marker of cognitive decline prior to diagnosis of multiple sclerosis

Background:

For many years, cognitive impairment has been established as a well-known symptom of multiple sclerosis. Moreover, we know that it was present even at the beginning of the disease.

Objective:

In this case-control study, we decided to evaluate whether there is an impairment of cognitive functions even before onset in those patients who will eventually suffer from multiple sclerosis.

Methods:

We evaluated the overall school performance, and particularly school performance in math and language in a group of patients who would later develop the disease and we compared our findings with a control group.

Results:

We found that school performance was poorer in subjects who were to become patients. And we found that the later the start of the first symptom, the better the qualifications.

Conclusion:

Testing a premorbid cognitive deficit by a validated indirect evaluation method allowed us to verify that there was evidence of neurological compromise even before a clinical diagnosis or the completion of the first magnetic resonance imaging in patients who would then suffer from multiple sclerosis.

There is still a role for the blink reflex in the diagnosis and follow-up of multiple sclerosis

OBJECTIVE

The evolution of the diagnostic criteria for multiple sclerosis (MS) has essentially evolved to clinical manifestations and magnetic resonance imaging. Inexpensive, quick to apply, non-invasive, quantitative and reliable neurophysiological tests are rare in daily practice and absent in clinical trials.

METHOD

The blink reflex was assessed in 50 patients with remitting-relapsing MS (RRMS) and 100 matched controls.

RESULTS

Patients with RRMS had abnormalities in the blink reflex waves in relation to controls. If only RRMS patients were considered, these abnormalities were more pronounced in patients with longer disease duration, higher disability and for those with clinical or image lesions in the brainstem.

CONCLUSION

Neurophysiological tests, such as the blink reflex, can be used for helping the diagnosis and follow-up of patients with RRMS, since the reflex can identify dissemination in time and in space in a clear and quantitative manner.

SIGNIFICANCE

Potential good methods for diagnosis and follow-up of MS should be considered for clinical trials and daily practice.

Brain networks disconnection in early multiple sclerosis cognitive deficits: an anatomofunctional study

Severe cognitive impairment involving multiple cognitive domains can occur early during the course of multiple sclerosis (MS). We investigated resting state functional connectivity changes in large-scale brain networks and related structural damage underlying cognitive dysfunction in patients with early MS. Patients with relapsing MS (3-5 years disease duration) were prospectively assigned to two groups based on a standardized neuropsychological evaluation: (1) cognitively impaired group (CI group, n = 15), with abnormal performances in at least 3 tests; (2) cognitively preserved group (CP group, n = 20) with normal performances in all tests. Patients and age-matched healthy controls underwent a multimodal 3T magnetic resonance imaging (MRI) including anatomical T1 and T2 images, diffusion imaging and resting state functional MRI. Structural MRI analysis revealed that CI patients had a higher white matter lesion load compared to CP and a more severe atrophy in gray matter regions highly connected to networks involved in cognition. Functional connectivity measured by integration was increased in CP patients versus controls in attentional networks (ATT), while integration was decreased in CI patients compared to CP both in the default mode network (DMN) and ATT. An anatomofunctional study within the DMN revealed that functional connectivity was mostly altered between the medial prefrontal cortex (MPFC) and the posterior cingulate cortex (PCC) in CI patients compared to CP and controls. In a multilinear regression model, functional correlation between MPFC and PCC was best predicted by PCC atrophy. Disconnection in the DMN and ATT networks may deprive the brain of compensatory mechanisms required to face widespread structural damage.

Factors affecting employment among informal caregivers assisting people with multiple sclerosis

The objective of this study was to identify characteristics of informal caregivers, caregiving, and the people with multiple sclerosis (MS) receiving assistance that are associated with reduced caregiver employment. Data were collected during telephone interviews with 530 MS caregivers, including 215 employed caregivers, with these survey data analyzed using logistic regression. Poorer cognitive ability by the care recipient to make decisions about daily tasks and more caregiving hours per week predicted reduced caregiver employment. Better physical health domains of caregiver quality of life were associated with significantly lower odds of reduced employment. Health professionals treating informal caregivers, as well as those treating people with MS, need to be aware of respite, support, and intervention programs available to MS caregivers and refer them to these programs, which could reduce the negative impact of caregiving on employment.

Use of Magnetic Resonance Imaging as Well as Clinical Disease Activity in the Clinical Classification of Multiple Sclerosis and Assessment of Its Course: A Report from an International CMSC Consensus Conference, March 5-7, 2010

It has recently been suggested that the Lublin-Reingold clinical classification of multiple sclerosis (MS) be modified to include the use of magnetic resonance imaging (MRI). An international consensus conference sponsored by the Consortium of Multiple Sclerosis Centers (CMSC) was held from March 5 to 7, 2010, to review the available evidence on the need for such modification of the Lublin-Reingold criteria and whether the addition of MRI or other biomarkers might lead to a better understanding of MS pathophysiology and disease course over time. The conference participants concluded that evidence of new MRI gadolinium-enhancing (Gd+) T1-weighted lesions and unequivocally new or enlarging T2-weighted lesions (subclinical activity, subclinical relapses) should be added to the clinical classification of MS in distinguishing relapsing inflammatory from progressive forms of the disease. The consensus was that these changes to the classification system would provide more rigorous definitions and categorization of MS course, leading to better insights as to the evolution and treatment of MS.

Subcutaneous interferon β-1a may protect against cognitive impairment in patients with relapsing-remitting multiple sclerosis: 5-year follow-up of the COGIMUS study

OBJECTIVE

To assess the effects of subcutaneous (sc) interferon (IFN) -1a on cognition over 5 years in mildly disabled patients with relapsing-remitting multiple sclerosis (RRMS).

METHODS

Patients aged 18-50 years with RRMS (Expanded Disability Status Scale score ≤4.0) who had completed the 3-year COGIMUS study underwent standardized magnetic resonance imaging, neurological examination, and neuropsychological testing at years 4 and 5. Predictors of cognitive impairment at year 5 were identified using multivariate analysis.

RESULTS

Of 331 patients who completed the 3-year COGIMUS study, 265 participated in the 2-year extension study, 201 of whom (75.8%; sc IFN β-1a three times weekly: 44 µg, n = 108; 22 µg, n = 93) completed 5 years' follow-up. The proportion of patients with cognitive impairment in the study population overall remained stable between baseline (18.0%) and year 5 (22.6%). The proportion of patients with cognitive impairment also remained stable in both treatment groups between baseline and year 5, and between year 3 and year 5. However, a significantly higher proportion of men than women had cognitive impairment at year 5 (26.5% vs 14.4%, p = 0.046). Treatment with the 22 versus 44 µg dose was predictive of cognitive impairment at year 5 (hazard ratio 0.68; 95% confidence interval 0.48-0.97).

CONCLUSIONS

This study suggests that sc IFN β-1a dose-dependently stabilizes or delays cognitive impairment over a 5-year period in most patients with mild RRMS. Women seem to be more protected against developing cognitive impairment, which may indicate greater response to therapy or the inherently better prognosis associated with female sex in MS.

Ask the Experts: Cognitive impairment in multiple sclerosis: progress, prevalence and management

Aurelie Ruet is part of Bruno Brochet’s team. She received her MD from the University Bordeaux-Segalen (Bordeaux, France), and completed her internship and residency in Neurology in the University Hospital of Bordeaux (France). She completed a PhD in Neuroscience at the University Bordeaux-Segalen. She has focused her research on identifying diagnostic and prognostic predictors in the early stages of multiple sclerosis and she has published papers on cognition in multiple sclerosis.

Bruno Brochet is Professor of Neurology at University Bordeaux-Segalen (Bordeaux, France) and Head of the Department of Neurology at the University Hospital of Bordeaux (France). He is a multiple sclerosis (MS) specialist and he created the MS Clinic of Bordeaux (France). He leads a clinical research group on MS, cognition and imagery.

Contribution of cortical lesion subtypes at 7T MRI to physical and cognitive performance in MS

OBJECTIVES

Evaluate cross-sectionally the contribution of focal cortical lesion (CL) subtypes at ultra-high-field MRI and traditional MRI metrics of brain damage to neurologic disability and cognitive performance in a heterogeneous multiple sclerosis (MS) cohort.

METHODS

Thirty-four patients with early or established disease including clinically isolated syndrome, relapsing-remitting MS, and secondary progressive MS were scanned on a human 7-tesla (7T) (Siemens) scanner to acquire fast low-angle shot (FLASH) T2*-weighted images for characterization of white matter and deep gray matter lesion volume, and CL types. Patients also underwent anatomical 3T MRI for cortical thickness estimation, and neuropsychological testing within 1 week of the 7T scan. Twenty-seven patient scans were acceptable for further analysis. Neurologic disability was measured using the Expanded Disability Status Scale.

RESULTS

Type III-IV CLs had the strongest relationship to physical disability (ρ = 0.670, p < 0.0001). White matter lesion volume and type I CLs are each significantly associated with 6 of 11 neuropsychological test variables. Type III-IV CLs significantly correlate with 4 of 11 neuropsychological test variables whereas type II CLs, deep gray matter lesion volume, and cortical thickness metrics are less frequently associated with cognitive performance.

CONCLUSIONS

Leukocortical (type I) and subpial (III-IV) CLs identified on 7T FLASH-T2* sequences are potential cortical biomarkers of cognitive and neurologic status in MS.

Cognitive impairment in multiple sclerosis

Cognitive impairment (CI) is a serious complication of multiple sclerosis (MS), and the domains affected are well established, but new affected domains such as theory of mind are still being identified. The evidence that disease-modifying therapies (DMTs) improve and prevent the development of CI in MS is not solid. Recent studies on the prevalence of CI in MS among people treated with DMT, although not as solid as studies completed prior to DMT introduction, suggest that CI remains a problem even among people on DMTs and that CI occurs frequently even at the very earliest stages of MS. Functional MRI studies and studies using diffusion tractography show that the impact of lesions on cognition depends on the particular cortical networks affected and their plasticity. Cognitive rehabilitation and L-amphetamine appear promising symptomatic treatments for CI in MS, while, cholinesterase inhibitors and memantine have failed, and data on Ginkgo and exercise are limited. We need more work to understand better CI in MS and develop treatments for this serious complication of MS.