Cognitive impairment in multiple sclerosis

The Effects of SARS-CoV-2 Infection on the Cognitive Functioning of Patients with Pre-Existing Dementia

Background

Cognitive postscripts of COVID-19, codenamed as 'cognitive COVID' or 'brain fog,' characterized by multidomain cognitive impairments, are now being reckoned as the most devastating sequelae of COVID-19. However, the impact on the already demented brain has not been studied.

Objective

We aimed to assess the cognitive functioning and neuroimaging following SARS-CoV-2 infection in patients with pre-existing dementia.

Methods

Fourteen COVID-19 survivors with pre-existing dementia (four with Alzheimer's disease, five with vascular dementia, three with Parkinson's disease dementia, and two with the behavioral variant of frontotemporal dementia) were recruited. All these patients had detailed cognitive and neuroimaging evaluations within three months before suffering from COVID-19 and one year later.

Results

Of the 14 patients, ten required hospitalization. All developed or increased white matter hyperintensities that mimicked multiple sclerosis and small vessel disease. There was a significant increase in fatigue (p = 0.001) and depression (p = 0.016) scores following COVID-19. The mean Frontal Assessment Battery (p < 0.001) and Addenbrooke's Cognitive Examination (p = 0.001) scores also significantly worsened.

Conclusion

The rapid progression of dementia, the addition of further impairments/deterioration of cognitive abilities, and the increase or new appearance of white matter lesion burden suggest that previously compromised brains have little defense to withstand a new insult (i.e., 'second hit' like infection/dysregulated immune response, and inflammation). 'Brain fog' is an ambiguous terminology without specific attribution to the spectrum of post-COVID-19 cognitive sequelae. We propose a new codename, i.e. 'FADE-IN MEMORY' (i.e., Fatigue, decreased Fluency, Attention deficit, Depression, Executive dysfunction, slowed INformation processing speed, and subcortical MEMORY impairment).

Remote administration of BICAMS measures and the Trail-Making Test to assess cognitive impairment in multiple sclerosis

Reliable remote cognitive testing could provide a safer assessment of cognitive impairment in multiple sclerosis (MS) during the COVID-19 pandemic and thereafter. Here we aimed to investigate the reliability and feasibility of administering Brief International Cognitive Assessment for MS (BICAMS) and the Trail-Making Test (TMT) to people with MS online. Between-group differences on BICAMS and the TMT were examined in a sample of 68 participants. Group 1 (N = 34) was tested in-person pre-pandemic. Group 2 was tested remotely. Within-group differences for in-person and virtual administrations were examined for Group 1. No significant differences between virtual and in-person administrations of the CVLT-II and SDMT were detected. BVMT-R scores were significantly higher for virtual administrations (M = 20.59, SD = 6.65) compared to in-person administrations (M = 16.35, SD = 6.05), possibly indicating inter-rater differences. Strong positive correlations were found for in-person and virtual scores within Group 1 on the CVLT-II (r = .84), SDMT (r = .85), TMT-A (r = .88), TMT-B (r = .76) and BVMT-R (r = .72). No significant differences between in-person and remote administrations of CVLT-II and SDMT in people living with MS were detected. Recommendations for future studies employing the TMT and BVMT-R online are provided.

Digital Biomarkers in Multiple Sclerosis

For incurable diseases, such as multiple sclerosis (MS), the prevention of progression and the preservation of quality of life play a crucial role over the entire therapy period. In MS, patients tend to become ill at a younger age and are so variable in terms of their disease course that there is no standard therapy. Therefore, it is necessary to enable a therapy that is as personalized as possible and to respond promptly to any changes, whether with noticeable symptoms or symptomless. Here, measurable parameters of biological processes can be used, which provide good information with regard to prognostic and diagnostic aspects, disease activity and response to therapy, so-called biomarkers Increasing digitalization and the availability of easy-to-use devices and technology also enable healthcare professionals to use a new class of digital biomarkers-digital health technologies-to explain, influence and/or predict health-related outcomes. The technology and devices from which these digital biomarkers stem are quite broad, and range from wearables that collect patients' activity during digitalized functional tests (e.g., the Multiple Sclerosis Performance Test, dual-tasking performance and speech) to digitalized diagnostic procedures (e.g., optical coherence tomography) and software-supported magnetic resonance imaging evaluation. These technologies offer a timesaving way to collect valuable data on a regular basis over a long period of time, not only once or twice a year during patients' routine visit at the clinic. Therefore, they lead to real-life data acquisition, closer patient monitoring and thus a patient dataset useful for precision medicine. Despite the great benefit of such increasing digitalization, for now, the path to implementing digital biomarkers is widely unknown or inconsistent. Challenges around validation, infrastructure, evidence generation, consistent data collection and analysis still persist. In this narrative review, we explore existing and future opportunities to capture clinical digital biomarkers in the care of people with MS, which may lead to a digital twin of the patient. To do this, we searched published papers for existing opportunities to capture clinical digital biomarkers for different functional systems in the context of MS, and also gathered perspectives on digital biomarkers under development or already existing as a research approach.

Significance of the Diagnosis of Executive Functions in Patients with Relapsing-Remitting Multiple Sclerosis

Multiple sclerosis (MS) is a progressive chronic disease of the Central Nervous System (CNS). Cognitive decline occurs rather rarely in relapsing–remitting multiple sclerosis (RRMS) compared to other types. The present study aimed to assess executive functions (EF) in relation to clinical and demographic variables in patients with RRMS. The study involved 22 individuals with RRMS (aged 23 to 49 years) and 22 matching controls. All the individuals with RRMS were in the remission phase. The assessments were carried out using MoCA, BDI-II, Halstead Category Test, Porteus Maze Test, verbal fluency tasks and Stroop Colour-Word Interference Test. The findings show that the two groups differed significantly in all the tests. All patients with RRMS in the remission phase presented at least one cognitive deficit, observed in general cognitive functioning, abstract reasoning or other executive functions, i.e., fluency, interference suppression, planning, or ability to modify activity in response to feedback. The deficits in most cases (except for those measured with the MoCA, Category Tests and phonemic fluency), are not related to intensity of depression and duration of the disease. Findings suggest that the diagnostic process in the case of patients with RRMS may include psychological assessment focusing on potentially existing cognitive, mainly executive, deficits and their severity.

N-acetyl cysteine administration affects cerebral blood flow as measured by arterial spin labeling MRI in patients with multiple sclerosis

BACKGROUND

The purpose of this study was to explore if administration of N-acetyl-cysteine (NAC) in patients with multiple sclerosis (MS) resulted in altered cerebral blood flow (CBF) based on Arterial Spin Labeling (ASL) magnetic resonance imaging (MRI).

METHODS

Twenty-three patients with mild to moderate MS, (17 relapsing remitting and 6 primary progressive) were randomized to either NAC plus standard of care (N = 11), or standard of care only (N = 12). The experimental group received NAC intravenously (50 mg/kg) once per week and orally (500mg 2x/day) the other six days. Patients in both groups were evaluated initially and after 2 months (of receiving the NAC or waitlist control) with ASL MRI to measure CBF. Clinical symptom questionnaires were also completed at both time points.

RESULTS

The CBF data showed significant differences in several brain regions including the pons, midbrain, left temporal and frontal lobe, left thalamus, right middle frontal lobe and right temporal/hippocampus (p < 0.001) in the MS group after treatment with NAC, when compared to the control group. Self-reported scores related to cognition and attention were also significantly improved in the NAC group as compared to the control group.

CONCLUSIONS

The results of this study suggest that NAC administration alters resting CBF in MS patients, and this is associated with qualitative improvements in cognition and attention. Given these findings, large scale efficacy studies will be of value to determine the potential clinical impact of NAC over the course of illness in patients with MS, as well as the most effective dosages and differential effects across subpopulations.

Comprehensive Approach to Management of Multiple Sclerosis: Addressing Invisible Symptoms-A Narrative Review

Multiple sclerosis (MS) is a chronic autoimmune inflammatory disease of the central nervous system, leading to neurodegeneration and manifesting as a variety of symptoms. These can include "invisible" symptoms, not externally evident to others, such as fatigue, mood disorders, cognitive impairments, pain, bladder/bowel dysfunction, sexual dysfunction, and vision changes. Invisible symptoms are highly prevalent in people living with MS, with multifactorial etiology and potential to impact the disease course. Patient experiences of these symptoms include both physical and psychosocial elements, which when unaddressed negatively influence many aspects of quality of life and perception of health. Despite the high impact on patient lives, gaps persist in awareness and management of these hidden symptoms. The healthcare provider and patient author experiences brought together here serve to raise the profile of invisible symptoms and review strategies for a team-based approach to comprehensive MS care. We summarize the current literature regarding the prevalence and etiology of invisible symptoms to convey the high likelihood that a person living with MS will contend with one or more of these concerns. We then explore how open communication between people living with MS and their care team, stigma mitigation, and shared decision-making are key to comprehensive management of invisible symptoms. We recommend validated screening tools and technological advancements that may be incorporated into MS care to regularly monitor these symptoms, offering insight into how healthcare providers can both educate and listen to patients, with the goal of improved patient quality of life. By pairing clinical knowledge with an understanding and consideration of the patient perspective, providers will be equipped to foster a patient-centered dialogue that encourages shared decision-making. Invisible symptoms of MS.

Vision, attention, and driving

Safe driving demands the coordination of multiple sensory and cognitive functions, such as vision and attention. Patients with neurologic or ophthalmic disease are exposed to selective pathophysiologic insults to driving-critical systems, placing them at a higher risk for unsafe driving and restricted driving privileges. Here, we evaluate how vision and attention contribute to unsafe driving across different patient populations. In ophthalmic disease, we focus on macular degeneration, glaucoma, diabetic retinopathy, and cataract; in neurologic disease, we focus on Alzheimer's disease, Parkinson's disease, and multiple sclerosis. Unsafe driving is generally associated with impaired vision and attention in ophthalmic and neurologic patients, respectively. Furthermore, patients with ophthalmic disease experience some degree of impairment in attention. Similarly, patients with neurologic disease experience some degree of impairment in vision. While numerous studies have demonstrated a relationship between impaired vision and unsafe driving in neurologic disease, there remains a dearth of knowledge regarding the relationship between impaired attention and unsafe driving in ophthalmic disease. In summary, this chapter confirms-and offers opportunities for future research into-the contribution of vision and attention to safe driving.

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.

Cognitive disturbances in the cuprizone model of multiple sclerosis

Cognitive problems frequently accompany neurological manifestations of multiple sclerosis (MS). However, during screening of preclinical candidates, assessments of behaviour in mouse models of MS typically focus on locomotor activity. In the present study, we analysed cognitive behaviour of 9 to 10-week-old female C57Bl/6J mice orally administered with the toxin cuprizone that induces demyelination, a characteristic feature of MS. Animals received 400 mg/kg cuprizone daily for 2 or 4 weeks, and their performance was compared with that of vehicle-treated mice. Cuprizone-treated animals showed multiple deficits in short touchscreen-based operant tasks: they responded more slowly to visual stimuli, rewards and made more errors in a simple rule-learning task. In contextual/cued fear conditioning experiments, cuprizone-treated mice showed significantly lower levels of contextual freezing than vehicle-treated mice. Diffusion tensor imaging showed treatment-dependent changes in fractional anisotropy as well as in axial and mean diffusivities in different white matter areas. Lower values of fractional anisotropy and axial diffusivity in cuprizone-treated mice indicated developing demyelination and/or axonal damage. Several diffusion tensor imaging measurements correlated with learning parameters. Our results show that translational touchscreen operant tests and fear conditioning paradigms can reliably detect cognitive consequences of cuprizone treatment. The suggested experimental approach enables screening novel MS drug candidates in longitudinal experiments for their ability to improve pathological changes in brain structure and reverse cognitive deficits.

A Novel, Integrative Approach for Evaluating Progression in Multiple Sclerosis: Development of a Scoring Algorithm

Background

There is an unmet need for a tool that helps to evaluate patients who are at risk of progressing from relapsing-remitting multiple sclerosis to secondary progressive multiple sclerosis (SPMS). A new tool supporting the evaluation of early signs suggestive of progression in multiple sclerosis (MS) has been developed. In the initial stage, concepts relevant to progression were identified using a mixed method approach involving regression on data from a real-world observational study and qualitative research with patients and physicians. The tool was drafted in a questionnaire format to assess these variables.

Objective

This study aimed to develop the scoring algorithm for the tool, using both quantitative and qualitative research methods.

Methods

The draft scoring algorithm was developed using two approaches: quantitative analysis of real-world data and qualitative analysis based on physician interviews and ranking and weighting exercises. Variables that were included in the draft tool and regarded as most clinically relevant were selected for inclusion in a multiple logistic regression. The analyses were run using physician-reported data and patient-reported data. Subsequently, a ranking and weighting exercise was conducted with 8 experienced neurologists as part of semistructured interviews. Physicians were presented with the variables included in the draft tool and were asked to rank them in order of strength of contribution to progression and assign a weight by providing a percentage of the overall contribution. Physicians were also asked to explain their ranking and weighting choices. Concordance between physicians was explored.

Results

Multiple logistic regression identified age, MS disease activity, and Expanded Disability Status Scale score as the most significant physician-reported predictors of progression to SPMS. Patient age, mobility, and self-care were identified as the strongest patient-reported predictors of progression to SPMS. In physician interviews, the variables ranked and weighted as most important were stability or worsening of symptoms, intermittent or persistent symptoms, and presence of ambulatory and cognitive symptoms. Across all physicians, the level of concordance was 0.278 (P<.001), indicating a low to moderate, but statistically significant, level of agreement. Variables were categorized as high (n=8), moderate (n=8), or low (n=10) importance based on the findings from the different approaches described above. Accordingly, the respective questions in the tool were assigned a weight of “three,” “two,” or “one” to inform the draft scoring algorithm.

Conclusions

This study further confirms the need for a tool to provide a consistent, comprehensive approach across physicians to support the early evaluation of signs indicative of progression to SPMS. The novel and comprehensive approach to develop the draft scoring algorithm triangulates data obtained from ranking and weighting exercises, qualitative interviews, and a real-world observational study. Variables that go beyond the clinically most obvious impairment in lower limbs have been identified as relevant subtle/sensitive signs suggestive of progressive disease.

The immediate effect of stroboscopic visual training on information-processing time in people with multiple sclerosis: an exploratory study

Stroboscopic visual training (SVT) is a form of training aimed at improving visual and perceptual performance by having individuals perform activities under conditions of intermittent vision. The efficacy of SVT has never been examined in people with multiple sclerosis (PwMS), therefore, our aim was to examine the immediate effect of SVT on cognitive function, gait and static balance performance in PwMS. This assessor-blinded, randomized crossover study included 26 PwMS, 16 females, mean age 47.9 and median EDSS score 4.5. Participants attended two sessions: SVT and control training. Exercises for both the SVT and control sessions were based on ball-catching tasks. Training sessions were identical in length (40-50 min) and type of exercise drills. The difference between the two practice regimes was that the SVT session was performed wearing stroboscopic glasses and the control training was performed with similar glasses without lenses. Cognition was evaluated by a computerized software (Mindstreams^®, NeuroTrax Corp., NY). Gait and balance were evaluated via wearable accelerometers (APDM, Oregon, USA). Outcome measures were collected twice during a single session, prior to training and immediately afterward. Information processing speed (p = 0.003) increased at the post-evaluation compared with baseline, solely in the SVT session. No differences between pre-post evaluations were observed for other cognitive scores following the SVT session. No differences between pre-post measurements were noted for gait and balance following the SVT session. The present study's results justify performing future RCT studies to examine the effects of a longer SVT program on cognition in PwMS.

Evaluating the feasibility and preliminary efficacy of a Cognitive Occupation-Based programme for people with Multiple Sclerosis (COB-MS): protocol for a feasibility cluster-randomised controlled trial

BACKGROUND

Cognitive difficulties experienced by people with multiple sclerosis (MS) impact their quality of life and daily functioning, from childcare and work, to social and self-care activities. Despite the high prevalence of cognitive difficulties seen in MS, there is a lack of developed programmes that target cognition, while also supporting patients by helping them to function well in everyday life. The Cognitive Occupation-Based programme for people with MS (COB-MS) was developed as a holistic, individualised cognitive rehabilitation intervention. It addresses the wide-ranging symptoms and functional difficulties that present in MS, including the ability to maintain employment, social activities, home management and self-care. The aim of the current research is to evaluate the feasibility and preliminary efficacy of COB-MS for people with MS. The focus is on feasibility outcomes as well as functioning associated with cognitive difficulty and secondary outcomes related to cognition, fatigue and quality of life.

METHODS

One hundred and twenty people with MS will be assigned to participate in either the COB-MS programme or a treatment as usual, wait-list control group as part of this single-blind, cluster-randomised controlled feasibility and preliminary efficacy trial of the COB-MS programme. The COB-MS group will participate in an eight-session occupational-based cognitive rehabilitation programme over 9 weeks. The primary outcome measure is the goal attainment scaling at 12 weeks. Participants will be assessed pre-intervention, post-intervention and at 12 weeks post-intervention and 6 months post-intervention. Qualitative evaluations of participants' perspectives will also be examined as part of the feasibility study.

DISCUSSION

Results will provide recommendations for a future definitive trial of COB-MS, with respect to both feasibility and preliminary, clinical efficacy. In the event that results indicate efficacy, study findings will suggest that COB-MS requires consideration as a means of enhancing cognitive and daily functioning in people living with MS.

TRIAL REGISTRATION

ISRCTN: ISRCTN11462710. Registered on 9 September 2019.

N-acetyl Cysteine Administration Is Associated With Increased Cerebral Glucose Metabolism in Patients With Multiple Sclerosis: An Exploratory Study

Background: Multiple Sclerosis (MS) is an autoimmune disease marked by progressive neurocognitive injury. Treatment options affording neuroprotective effects remain largely experimental. The purpose of this proof of concept study was to explore the effects of N-acetyl-cysteine (NAC) on cerebral glucose metabolism (CMRGlu) and symptoms in patients with multiple sclerosis (MS).

Methods: Twenty-four patients with MS were randomized to either NAC plus standard of care, or standard of care only (waitlist control). The experimental group received NAC intravenously once per week and orally the other 6 days. Patients in both groups were evaluated at baseline and after 2 months (of receiving the NAC or waitlist control period) with an integrated Position Emission Tomography (PET)/ Magnetic Resonance Imaging (MRI) scanner, using 18F Fluorodeoxyglucose (FDG) to measure cerebral glucose metabolism. Following imaging evaluation at 2 months, subjects initially attributed to the standard of care arm were eligible for treatment with NAC. Clinical and symptom questionnaires were also completed initially and after 2 months.

Results: The FDG PET data showed significantly increased cerebral glucose metabolism in several brain regions including the caudate, inferior frontal gyrus, lateral temporal gyrus, and middle temporal gyrus (p < 0.05) in the MS group treated with NAC, as compared to the control group. Self-reported scores related to cognition and attention were also significantly improved in the NAC group as compared to the control group.

Conclusions: The results of this study suggest that NAC positively affects cerebral glucose metabolism in MS patients, which is associated with qualitative, patient reported improvements in cognition and attention. Larger scale studies may help to determine the clinical impact of NAC on measures of functioning over the course of illness, as well as the most effective dosage and dosage regimen.

Cognitive Efficacy of Pharmacologic Treatments in Multiple Sclerosis: A Systematic Review

INTRODUCTION

Cognitive impairment is prevalent and debilitating among persons with multiple sclerosis (MS). While many pharmacologic treatments have shown good efficacy in reducing clinical relapses, brain lesions, and improving certain physical symptoms, their efficacy for improving cognitive function is not well understood.

OBJECTIVES

The current systematic review aimed to evaluate the efficacy of pharmacologic treatments for improving cognitive function among persons with MS.

METHODS

A literature search was conducted through the PubMed and PsycINFO databases. Two independent reviewers assessed each paper, and a third reviewer weighed in if the two reviewers could not reach a consensus. Classification of evidence was determined using the 2017 American Academy of Neurology (AAN) criteria for therapeutic trials. Standardized effect sizes (Cohen's d) were calculated to compare across studies.

RESULTS

Eighty-seven journal articles published between 1990 and January 2020 were included in the current review. Overall, there is insufficient evidence to support the use of pharmacologic treatments to improve cognitive function in persons with MS. There were many contradictory findings observed in this review, which may be due to possible unidentified moderating treatment response variables and/or lack of standardization in assessment procedures. There was also an overreliance on statistical significance (most papers did not provide sizes of treatment effects), which may not be clinically meaningful.

CONCLUSIONS

Higher-quality randomized controlled trials are needed to establish the cognitive efficacy of pharmacologic treatments for MS-related cognitive dysfunction, with cognition as the primary endpoint. Researchers are urged to use standardized criteria (such as the AAN criteria) to guide their research designs. Clinicians should consider effect sizes of studies before deciding whether to prescribe certain medications to ameliorate cognitive symptoms.

Computer Aided Diagnosis System for multiple sclerosis disease based on phase to amplitude coupling in covert visual attention

BACKGROUND AND OBJECTIVE

Computer Aided Diagnosis (CAD) techniques have widely been used in research to detect the neurological abnormalities and improve the consistency of diagnosis and treatment in medicine. In this study, a new CAD system based on EEG signals was developed. The motivation for the development of the CAD system was to diagnose multiple sclerosis (MS) disease during covert visual attention tasks. It is worth noting that research of this kind on the efficacy of attention tasks is limited in scope for MS patients; therefore, it is vital to develop a feature of EEG to characterize the patient's state with high sensitivity and specificity.

METHODS

We evaluated the use of phase-amplitude coupling (PAC) of EEG signals to diagnose MS. It is assumed that the role of PAC for information encoding during visual attention in MS is greatly unknown; therefore, we made an attempt to investigate it via CAD systems. The EEG signals were recorded from healthy and MS patients while performing new visual attention tasks. Machine learning algorithms were also used to identify the EEG signals as to whether the disease existed or not. The challenge regarding the dimensionality of the extracted features was addressed through selecting the relevant and efficient features using T-test and Bhattacharyya distance criteria, and the validity of the system was assessed through leave-one-subject-out cross-validation method.

RESULTS

Our findings indicated that online sequential extreme learning machine (OS-ELM) classifier with T-test feature selection method yielded peak accuracy, sensitivity and specificity in both color and direction tasks. These values were 91%, 83% and 96% for color task, and 90%, 82% and 96% for the direction task.

CONCLUSIONS

Based on the results, it can be concluded that this procedure can be used for the automatic diagnosis of early MS, and can also facilitate the treatment assessment in patients.

Uncovering the association between fatigue and fatigability in multiple sclerosis using cognitive control

BACKGROUND

Fatigue and cognitive dysfunction are two common symptoms experienced by patients with multiple sclerosis (MS). The relationship between subjective and objective fatigue (fatigability) in MS is poorly understood. Cognitive control tasks might be more conducive to fatigability and more likely to show associations between subjective and objective cognitive fatigue in MS.

OBJECTIVE

To study the association between objective fatigability, as induced by a cognitive control task called the Blocked Cyclic Naming Task (BCNT), subjective fatigue and baseline cognitive functioning in patients with MS.

METHODS

Twenty-one patients with MS completed baseline questions about their disease, the Montreal Cognitive Assessment (MoCA) battery and self-reported questionnaires on trait fatigue, sleep and depression. Disability was captured using the expanded disability status scale (EDSS). Participants then performed the BCNT and were asked about their level of state momentary fatigue before and after the BCNT. The BCNT consists of several blocks of either related or unrelated pictures that participants name as quickly as possible. The pictures cycled 4 times in each block and the difference in the response times (RTs) between related and unrelated blocks was captured. Data were analyzed using repeated measures analysis of variance and Pearson correlations.

RESULTS

MS participants' performance declined for the related, but not unrelated blocks. The difference in RTs between related and unrelated conditions increased with repetition across cycles (p < 0.001). Participants also showed objective fatigability with less repetition priming (p = 0.02) in the 4th quarter and with greater differences between related and unrelated conditions in the later part of the task. Objective fatigability was strongly associated with participants' assessment of their level of momentary state fatigue (r = 0.612, p = 0.007).

CONCLUSION

Using the appropriate tools, this study showed an association between subjective and objective cognitive fatigue in people with MS. The BCNT and cognitive control are useful tools in assessing patients with MS and should be explored in future, larger studies in this population.

Correlation between cortical lesions and cognitive impairment in multiple sclerosis

OBJECTIVES

Gray matter (GM) damage is well known as a fundamental aspect of multiple sclerosis (MS). Above all, cortical lesions (CLs) burden, detectable at MRI with double inversion recovery (DIR) sequences, has been demonstrated to correlate with cognitive impairment (CI). The aim of this study was to investigate the role of CLs number in predicting CI in a cohort of patients with MS in a clinical practice setting.

MATERIALS AND METHODS

Thirty consecutive patients with MS presenting CLs (CL+) at high-field (3.0 T) MRI 3D-DIR sequences and an even group of MS patients without CLs (CL-) as a control, were investigated with the Rao Brief Repeatable Battery of Neuropsychological Tests (BRB), Version A. Total and lobar CLs number were computed in CL+ patients.

RESULTS

Among the sixty patients with MS enrolled, forty-seven (78.3%) had a relapsing-remitting course, while thirteen (21.7%) a progressive one, eleven secondary progressive, and two primary progressive. Compared to CL-, CL+ patients had a greater proportion of progressive forms (p = .03). The most affected region was the frontal lobe (73.3% of patients), followed by temporal and parietal ones (both 60.0%). Multivariate (logistic regression) analysis revealed a significant correlation between total CLs number and the presence of mild cognitive impairment defined as pathologic score in at least one BRB test (p = .04); it was also correlated with deficit at PASAT 3 (p = .05) and Stroop Test (p = .02).

CONCLUSIONS

We confirmed CLs number, evaluated with a technique quite commonly available in clinical practice, as a predictive factor of CI in patients with MS, in order to improve the diagnosis and management of CI and monitor potential neuroprotective effects of therapies.

[New aspects of symptomatic MS treatment: Part 6 - cognitive dysfunction and rehabilitation]

The symptomatic treatment of multiple sclerosis (MS) is nowadays of similar importance as immunotherapy within a comprehensive treatment concept of this chronic disease. It makes a considerable contribution to the reduction of disabilities in activities of daily living as well as social and occupational life. Moreover, symptomatic treatment is of great importance for amelioration of the quality of life. Since our last survey of symptomatic MS treatment in 2004 and publication of the guidelines of the German Neurological Society and the Clinical Competence Network Multiple Sclerosis ("Klinisches Kompetenznetz Multiple Sklerose", KKN-MS) in 2014 several developments within the topics of mobility, bladder and sexual function, vision, fatigue, cognition and rehabilitation have taken place. These new findings together with further aspects of disease measurement methods and overall treatment strategies of the respective symptoms, as well as treatment goals are introduced in several individual contributions. In this article the symptoms of cognitive disorders and the growing impact of rehabilitation are discussed.

Brain connectivity and cognitive processing speed in multiple sclerosis: A systematic review

BACKGROUND

Processing speed (PS) decline is the most commonly observed cognitive deficit in people with multiple sclerosis (MS) resulting in a significant impact on quality of life. Despite its importance, knowledge of the underlying neural substrates is lacking.

OBJECTIVE

As MS is increasingly recognised as a disconnection syndrome, our aim was to carry out a systematic literature review to clarify the relationship between PS performance and MRI measures of structural and functional brain connectivity in people with MS.

SEARCH METHODS

A literature search was carried out on PubMed and Web of Science that included publications predating September 2017. Additional articles were added after inspection of the reference lists of all selected papers.

DATA EXTRACTION

All selected papers were categorised in three sections according to the MRI measures investigated, independently or both. Quality assessment was carried out using a customised set of criteria.

RESULTS

Thirty-two articles met the inclusion criteria and were included in the review. Microstructural integrity of the anterior corpus callosum and functional connectivity of frontal areas were more consistently found to correlate with PS performance, though high variability of findings was observed across studies. Several methodological flaws emerged from the reviewed literature.

CONCLUSIONS

Despite the observed trends, no definite conclusions can be drawn on the relationship between brain connectivity and PS decline in MS given the limitations of the current literature. Future investigations may benefit from theoretical and methodological advances to clarify how MS-related brain damage affects patients' cognition.

Potential neuroprotective effect of Fingolimod in multiple sclerosis and its association with clinical variables

INTRODUCTION

Multiple sclerosis (MS) is a chronic inflammatory, demyelinating disease of the central nervous system affecting both white matter and grey matter in the earliest phases of its course. The crucial role of neurodegeneration in disability progression in MS, regardless of white matter damage, has been confirmed by several imaging and neuropathological studies. Fingolimod is an effective immunomodulator of the sphingosine 1-phosphate receptor, approved in relapsing remitting MS and able to cross the blood-brain barrier and to slow disability progression and brain volume loss. However, it remains unclear whether this neuroprotective action is due to a peripheral anti-inflammatory effect and/or to a direct effect on neuronal cells.

AREAS COVERED

In this review, the authors summarize the published preclinical and clinical studies on the effect of Fingolimod in limiting the focal and diffuse grey matter damage in MS.

EXPERT OPINION

Fingolimod might have a significant neuroprotective effect on relapsing remitting MS based on its modulatory effect on oligodendroglial cells and astrocytes, and on its direct effect on cortical neurons. Future clinical studies including measures of grey matter damage are required to confirm in vivo such neuroprotective effect.

Cognitive rehabilitation and mindfulness in multiple sclerosis (REMIND-MS): a study protocol for a randomised controlled trial

Background

Cognitive problems frequently occur in patients with multiple sclerosis (MS) and profoundly affect their quality of life. So far, the best cognitive treatment options for MS patients are a matter of debate. Therefore, this study aims to investigate the effectiveness of two promising non-pharmacological treatments: cognitive rehabilitation therapy (CRT) and mindfulness-based cognitive therapy (MBCT). Furthermore, this study aims to gain additional knowledge about the aetiology of cognitive problems among MS patients, since this may help to develop and guide effective cognitive treatments.

Methods/design

In a dual-centre, single-blind randomised controlled trial (RCT), 120 MS patients will be randomised into one of three parallel groups: CRT, MBCT or enhanced treatment as usual (ETAU). Both CRT and MBCT consist of a structured 9-week program. ETAU consists of one appointment with an MS specialist nurse. Measurements will be performed at baseline, post-intervention and 6 months after the interventions. The primary outcome measure is the level of subjective cognitive complaints. Secondary outcome measures are objective cognitive function, functional brain network measures (using magnetoencephalography), psychological symptoms, well-being, quality of life and daily life functioning.

Discussion

To our knowledge, this will be the first RCT that investigates the effect of MBCT on cognitive function among MS patients. In addition, studying the effect of CRT on cognitive function may provide direction to the contradictory evidence that is currently available. This study will also provide information on changes in functional brain networks in relation to cognitive function. To conclude, this study may help to understand and treat cognitive problems among MS patients.

Trial registration

This trial was prospectively registered at the Dutch Trial Registration (number NTR6459, registered on 31 May 2017).

Effort and neuropsychological performance in HIV-infected individuals on stable combination antiretroviral therapy

The expression of cognitive symptoms associated with HIV varies over time and across individuals. This pattern may reflect transient contextual factors, including the degree of effort exerted by individuals undergoing cognitive testing. The present study examined whether effort corresponds to the expression of persistent HIV-related cognitive impairment among individuals receiving combination antiretroviral therapy (cART). HIV+ individuals (n = 111) averaged 48.2 (14.9) years of age and 13.0 (2.7) years of education and HIV- individuals (n = 92) averaged 34.9 (17.2) years of age and 13.5 (1.9) years of education. Participants completed a neuropsychological battery and a clinically validated measure of effort (Test of Memory Malingering, trial 1). Results revealed that the vast majority of HIV+ (85%) and HIV- (89%) individuals performed above published guidelines for adequate effort. Furthermore, the expression of cognitive impairment in HIV was not related to effort performance. The results were unchanged when examining HIV+ individuals with and without viral suppression. Finally, disability and disability-seeking status, and a proxy measure of apathy did not correspond to effort levels in HIV+ individuals. These findings suggest that variability in the expression of cognitive impairment in the cART era is unlikely to represent overt effort failures or other confounds unrelated to the disease. Persistent cognitive impairment in HIV likely represents historical and/or ongoing disease mechanisms despite otherwise successful treatment.

Cognitive Impairment in Multiple Sclerosis: A Review of Neuropsychological Assessments

Of the more than two million people worldwide with multiple sclerosis, 40% to 65% experience cognitive impairment, many of them early in the course of the disease. Cognitive impairment has been found in patients with all subtypes of multiple sclerosis. Because both pharmacologic and nonpharmacologic interventions may improve patients' brain function, cognitive assessment should be a routine part of the clinical evaluation. Traditional paper-and-pencil neuropsychological tests and batteries can help detect and monitor patients' cognitive problems. Computerized cognitive batteries also show promise. Controversy continues over which test is most reliable at assessing cognitive impairment in both everyday clinical practice and research. Each battery has possible disadvantages, such as practice effects, poor sensitivity and specificity, and questionable applicability to multiple sclerosis. Based on our review of the literature, we describe the tests that are currently being used or that might be used in assessing cognitive deficits in patients with multiple sclerosis, and we summarize the strengths and limitations of each.

Cognitive functions over the course of 1 year in multiple sclerosis patients treated with disease modifying therapies

OBJECTIVES

Disease-modifying therapies (DMTs) are applied to delay or prevent disease progression in multiple sclerosis (MS). While this has mostly been proven for physical symptoms, available studies regarding long-term effects of DMTs on cognitive functions are rare and sometimes inconsistent due to methodological shortcomings. Particularly in the case of fingolimod, comprehensive data on cognitive functions are not yet available. Therefore, we set out to reliably assess cognitive functions in patients with relapsing-remitting MS (RRMS) treated with DMTs over 1 year.

METHODS

Cognitive functions were assessed with eight tests at three timepoints: baseline, 6-month follow up and 12-month follow up. First, we investigated whether the stability of cognitive functions (i.e. not falling below the 5% cut-off in more than one test) over 1 year in RRMS patients (n = 41) corresponds to the stability in healthy individuals (n = 40) of a previous study. Second, we compared the percentage of declined and improved patients in the different tests. Third, we compared patients treated with fingolimod (n = 22) with patients treated with natalizumab (n = 11) with regard to cognitive stability. Fourth, based on the patient data, the Reliable Change Index was applied to compute cut-offs for reliable cognitive change.

RESULTS

Approximately 75% of RRMS patients treated with DMTs remained stable over the course of 1 year. The Paced Auditory Serial Addition Test (PASAT) and the Spatial Recall Test (SPART), produced improvements in 12.5% and 30.6%, respectively, probably due to practice effects. Patients treated with fingolimod did not differ from patients treated with natalizumab with regard to cognitive stability.

CONCLUSIONS

Cognitive functions remain relatively stable under DMT treatment over 1 year, irrespective of the type of medication. Furthermore, the tests PASAT and SPART should be interpreted cautiously in studies examining performance changes over time. The provided RCI norms may help clinicians to determine whether a difference in two measurements observed in a RRMS patient is reliable.

Impairment of visuospatial/visuoconstructional skills in multiple sclerosis patients: the correlation with regional lesion load and subcortical atrophy

INTRODUCTION

About 20% to 26% of patients with multiple sclerosis (MS) show alterations in visuospatial/visuoconstructive (VS-VC) skills even though temporo-parieto-occipital impairment is a frequent finding in magnetic resonance imaging. No studies have specifically analysed the relationship between these functions and lesion volume (LV) in these specific brain areas.

OBJECTIVE

To evaluate the relationship between VS-VC impairment and magnetic resonance imaging temporo-parieto-occipital LV with subcortical atrophy in patients with MS.

METHODOLOGY

Of 100 MS patients undergoing a routine neuropsychological evaluation, 21 were selected because they displayed VS-VC impairments in the following tests: Incomplete picture, Block design (WAIS-III), and Rey-Osterrieth complex figure test. We also selected 13 MS patients without cognitive impairment (control group). Regional LV was measured in FLAIR and T1-weighted images using a semiautomated method; subcortical atrophy was measured by bicaudate ratio and third ventricle width. Partial correlations (controlling for age and years of school) and linear regression analysis were employed to analyse correlations between magnetic resonance imaging parameters and cognitive performance.

RESULTS

All measures of LV and brain atrophy were significantly higher in patients with cognitive impairment. Regional LV, bicaudate ratio, and third ventricle width are significantly and inversely correlated with cognitive performance; the strongest correlation was between third ventricle width and VC performance (Block design: P=.001; Rey-Osterrieth complex figure: P<.000). In the multivariate analysis, third ventricle width only had a significant effect on performance of VC tasks (Block design: P=.000; Rey-Osterrieth complex figure: P=.000), and regional FLAIR VL was linked to the VS task (Incomplete picture; P=.002).

CONCLUSIONS

Measures of subcortical atrophy explain the variations in performance on visuocostructive tasks, and regional FLAIR VL measures are linked to VS tasks.

Remote cognitive assessments for patients with multiple sclerosis: a feasibility study

BACKGROUND

measuring cognitive function in patients with multiple sclerosis (MS) can be challenging given the obstacles faced when traveling to testing centers.

OBJECTIVE

the purpose of this study was to evaluate the feasibility of remote cognitive assessment in patients with MS using the automated neuropsychological assessment metrics (ANAM-MS) and the symbol digit modalities test (SDMT).

METHODS

patients meeting the McDonald criteria for MS (n = 24) were randomized to complete the live-in-office condition or a remote-in-office condition first, with all patients completing both sessions. Patients (n = 20) then completed a final remote-in-home testing session. Both remote sessions were proctored by a psychologist using a secure telehealth connection.

RESULTS

scores on the live SDMT differed from scores in the two remote settings F(2, 38) = 4.46, p = 0.018. However, summary scores on the ANAM-MS were similar across the three settings, F(2, 36) = 2.21, p = 0.124. Satisfaction with telehealth testing was high on the part of the examiner and patients. Each telehealth testing session saved more than $144.00 in travel costs and lost wages.

CONCLUSION

this study demonstrated that valid results can be obtained when evaluating patients remotely using ANAM-MS. Some differences were noted for the SDMT that suggest that either specific norms or a different implementation approach may be needed for telehealth.

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.

Linguistic and psychometric validation of the MSSS-88 questionnaire for patients with multiple sclerosis and spasticity in Germany

BACKGROUND

Multiple sclerosis (MS) is an inflammatory disease where many of the patients suffer from spasticity impacting their quality-of-life. The purpose of this paper was to linguistically validate and psychometrically test the Multiple Sclerosis Spasticity Scale (MSSS-88) in German speaking MS patients.

METHODS

The study had two stages: 1) forward/backward translations of the original MSSS-88 scale into German, discussions with MS-experts and cognitive debriefings with MS patients; 2) psychometric evaluation of the German version. Data collection took part in an observational multi-centre study in Germany (MOVE2).

RESULTS

The German translation of the MSSS-88 scale was discussed with three MS-experts; followed by two cognitive debriefing sessions with 12 MS patients. For psychometric evaluation the MSSS-88 was filled in by 87 MS patients with a mean age of 50.2 ± 10.4 years; 26.4% of them had severe spasticity. Data quality was acceptable. Missing data for items of the MSSS-88 were low (range 0-5.75%). Psychometric testing of the MSSS-88 revealed excellent values for reliability and validity. Significant differences between groups regarding severity, grading, type and self-ratings of MS-spasticity and sleep disturbances were found. Sensitivity to change could be demonstrated for the MSSS-88 in the group of MS patients treated with cannabinoid oromucosal spray vs. non-treated patients. In the treated group significant changes with a moderate effect size were found for 'muscle spasms', 'emotional health' and 'pain/discomfort'. No significant changes could be detected in the non-treated group.

CONCLUSION

Preliminary evidence from this small study supports reliability, validity, and responsiveness of the German version of the MSSS-88 for measuring the impact of spasticity in MS.

Cognitive and affective assessments of multiple sclerosis (MS) and neuromyelitis optica (NMO) patients utilizing computerized touch panel-type screening tests

OBJECTIVE

Cognitive and affective dysfunctions are important aspects for patients with multiple sclerosis (MS) and neuromyelitis optica (NMO).

METHODS

We herein examined the cognitive and affective ability in MS (n=35) and NMO (n=10) patients using computerized touch panel-type screening tests.

RESULTS

While MS patients and normal controls (NC1, n=40) did not significantly differ in their scores from the Hasegawa dementia scale-revised (HDS-R) or the frontal assessment battery, MS patients did score significantly lower on the mini-mental state examination (MMSE). In contrast, NMO patients did not differ from the normal control group 2 (NC2, n=15) in any of the three cognitive assessments. We also examined the affective ability and found that MS patients scored significantly higher on the apathy scale (AS) compared with the NC1 group, while NMO patients scored significantly higher on the geriatric depression scale (GDS) compared with the NC2 group. Although the GDS and AS scores did not correlate with any of the cognitive assessments among MS patients, the AS scores did correlate with the MMSE and HDS-R among NMO patients. Compared with normal controls, the times to complete the flipping cards and arranging pictures games were significantly longer for MS patients but not for NMO patients.

CONCLUSION

These results indicate differences between some features of cognitive and affective dysfunctions between MS and NMO patients. Computerized touch panel-type screening tests may be a more useful and sensitive tool for the cognitive assessment of MS patients than NMO patients.

Altered likelihood of brain activation in attention and working memory networks in patients with multiple sclerosis: an ALE meta-analysis

Multiple sclerosis (MS) is a chronic neurological disease, frequently affecting attention and working memory functions. Functional imaging studies investigating those functions in MS patients are hard to compare, as they include heterogeneous patient groups and use different paradigms for cognitive testing. The aim of this study was to investigate alterations in neuronal activation between MS patients and healthy controls performing attention and working memory tasks. Two meta-analyses of previously published fMRI studies investigating attention and working memory were conducted for MS patients and healthy controls, respectively. Resulting maps were contrasted to compare brain activation in patients and healthy controls. Significantly increased brain activation in the inferior parietal lobule and the dorsolateral prefrontal cortex was detected for healthy controls. In contrast, higher neuronal activation in MS patients was obtained in the left ventrolateral prefrontal cortex and the right premotor area. With this meta-analytic approach previous results of investigations examining cognitive function using fMRI are summarized and compared. Therefore a more general view on cognitive dysfunction in this heterogeneous disease is enabled.

Structural connectomics in brain diseases

Imaging the connectome in vivo has become feasible through the integration of several rapidly developing fields of science and engineering, namely magnetic resonance imaging and in particular diffusion MRI on one side, image processing and network theory on the other side. This framework brings in vivo brain imaging closer to the real topology of the brain, contributing to narrow the existing gap between our understanding of brain structural organization on one side and of human behavior and cognition on the other side. Given the seminal technical progresses achieved in the last few years, it may be ready to tackle even greater challenges, namely exploring disease mechanisms. In this review we analyze the current situation from the technical and biological perspectives. First, we critically review the technical solutions proposed in the literature to perform clinical studies. We analyze for each step (i.e. MRI acquisition, network building and network statistical analysis) the advantages and potential limitations. In the second part we review the current literature available on a selected subset of diseases, namely, dementia, schizophrenia, multiple sclerosis and others, and try to extract for each disease the common findings and main differences between reports.