Preclinical disease activity in multiple sclerosis: A prospective study of cognitive performance prior to first symptom

Shifting our attention earlier in the multiple sclerosis disease course

PURPOSE OF REVIEW

Revisions of multiple sclerosis (MS) diagnostic criteria enable clinicians to diagnose patients earlier in the biologic disease course. Prompt initiation of therapy correlates with improved clinical outcomes. This has led to increased attention on the earliest stages of MS, including the MS prodrome and radiologically isolated syndrome (RIS). Here, we review current understanding and approach to patients with preclinical MS.

RECENT FINDINGS

MS disease biology often begins well before the onset of typical MS symptoms, and we are increasingly able to recognize preclinical and prodromal stages of MS. RIS represents the best characterized aspect of preclinical MS, and its diagnostic criteria were recently revised to better capture patients at highest risk of conversion to clinical MS. The first two randomized control trials evaluating disease modifying therapy use in RIS also found that treatment could delay or prevent onset of clinical disease.

SUMMARY

Despite progress in our understanding of the earliest stages of the MS disease course, additional research is needed to systematically identify patients with preclinical MS as well as capture those at risk for developing clinical disease. Recent data suggests that preventive immunomodulatory therapies may be beneficial for high-risk patients with RIS; though management remains controversial.

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.

An autoantibody signature predictive for multiple sclerosis

Although B cells are implicated in multiple sclerosis (MS) pathophysiology, a predictive or diagnostic autoantibody remains elusive. In this study, the Department of Defense Serum Repository (DoDSR), a cohort of over 10 million individuals, was used to generate whole-proteome autoantibody profiles of hundreds of patients with MS (PwMS) years before and subsequently after MS onset. This analysis defines a unique cluster in approximately 10% of PwMS who share an autoantibody signature against a common motif that has similarity with many human pathogens. These patients exhibit antibody reactivity years before developing MS symptoms and have higher levels of serum neurofilament light (sNfL) compared to other PwMS. Furthermore, this profile is preserved over time, providing molecular evidence for an immunologically active preclinical period years before clinical onset. This autoantibody reactivity was validated in samples from a separate incident MS cohort in both cerebrospinal fluid and serum, where it is highly specific for patients eventually diagnosed with MS. This signature is a starting point for further immunological characterization of this MS patient subset and may be clinically useful as an antigen-specific biomarker for high-risk patients with clinically or radiologically isolated neuroinflammatory syndromes.

Identification and management of subclinical disease activity in early multiple sclerosis: a review

IMPORTANCE

Early treatment initiation in multiple sclerosis (MS) is crucial in preventing irreversible neurological damage and disability progression. The current assessment of disease activity relies on relapse rates and magnetic resonance imaging (MRI) lesion activity, but inclusion of other early, often "hidden," indicators of disease activity may describe a more comprehensive picture of MS.

OBSERVATIONS

Early indicators of MS disease activity other than relapses and MRI activity, such as cognitive impairment, brain atrophy, and fatigue, are not typically captured by routine disease monitoring. Furthermore, silent progression (neurological decline not clearly captured by standard methods) may occur undetected by relapse and MRI lesion activity monitoring. Consequently, patients considered to have no disease activity actually may have worsening disease, suggesting a need to revise MS management strategies with respect to timely initiation and escalation of disease-modifying therapy (DMT). Traditionally, first-line MS treatment starts with low- or moderate-efficacy therapies, before escalating to high-efficacy therapies (HETs) after evidence of breakthrough disease activity. However, multiple observational studies have shown that early initiation of HETs can prevent or reduce disability progression. Ongoing randomized clinical trials are comparing escalation and early HET approaches.

CONCLUSIONS AND RELEVANCE

There is an urgent need to reassess how MS disease activity and worsening are measured. A greater awareness of "hidden" indicators, potentially combined with biomarkers to reveal silent disease activity and neurodegeneration underlying MS, would provide a more complete picture of MS and allow for timely therapeutic intervention with HET or switching DMTs to address suboptimal treatment responses.

Instability of excitatory synapses in experimental autoimmune encephalomyelitis and the outcome for excitatory circuit inputs to individual cortical neurons

Synapses are lost on a massive scale in the brain and spinal cord of people living with multiple sclerosis (PwMS), and this synaptic loss extends far beyond demyelinating lesions. Post-mortem studies show the long-term consequences of multiple sclerosis (MS) on synapses but do not inform on the early impacts of neuroinflammation on synapses that subsequently lead to synapse loss. How excitatory circuit inputs are altered across the dendritic tree of individual neurons under neuroinflammatory stress is not well understood. Here, we directly assessed the structural dynamics of labeled excitatory synapses in experimental autoimmune encephalomyelitis (EAE) as a model of immune-mediated cortical neuronal damage. We used in vivo two-photon imaging and a synthetic tissue-hydrogel super-resolution imaging technique to reveal the dynamics of excitatory synapses, map their location across the dendritic tree of individual neurons, and examine neurons at super-resolution for synaptic loss. We found that excitatory synapses are destabilized but not lost from dendritic spines in EAE, starting with the earliest imaging session before symptom onset. This led to changes in excitatory circuit inputs to individual cells. In EAE, stable synapses are replaced by synapses that appear or disappear across the imaging sessions or repeatedly change at the same location. These unstable excitatory inputs occur closer to one another in EAE than in healthy controls and are distributed across the dendritic tree. When imaged at super-resolution, we found that a small proportion of dendritic protrusions lost their presynapse and/or postsynapse. Our finding of diffuse destabilizing effects of neuroinflammation on excitatory synapses across cortical neurons may have significant functional consequences since normal dendritic spine dynamics and clustering are essential for learning and memory.

Impulsivity and attention deficit-hyperactivity symptoms among patients with relapsing-remitting multiple sclerosis: a case-control study

BACKGROUND AND OBJECTIVES

Multiple sclerosis(MS) is a progressive, autoimmune, neurodegenerative disease.Studies have suggested that autoimmune diseases play a role in the pathogenesis of Attention deficit and hyperactivity disorder(ADHD).We aim to evaluate ADHD symptoms among patients with RRMS(pwRRMS).

METHODS

The study included 48 RRMS patients and 54 healthy controls. ADHD symptoms were assessed by self-report questionnaires and performance tests.Beck Depression Inventory (BDI), Turgay's Turkish version of Adult-ADD/ADHD (A-ADHD), Barratt Impulsivity Scale (BIS-11), and World Health Organization Quality of Life-Short Form (WHOQoL-Bref) were completed by the participants.Stroop Colour and Word Interference Test - TBAG Form (SCWT); was used for assessing cognitive function by a trained psychiatrist. Fatigue Severity Scale (FSS) and Expanded Disability Status Scale (EDSS) were used to evaluate by pwRRMS.

RESULTS

PwRRMS had significantly higher attention-deficit scores and poor performance in all SCWT subtests.All SCWT scores were positively correlated with MS duration.A-ADHD-Total scores were negatively correlated with the age of MS diagnosis.A moderate positive correlation was found between falls and A-ADHD-total scores, and psychomotor speed.A moderate negative correlation was found between WHOQoL-Bref scores and BID, FSS, ADHD-Attention Deficit, SCWT-3, SCWT-5, and SCWT-interference.In multivariate linear regression analyzes, attention-deficit predicted EDSS positively, while depressive symptoms, attention-deficit, and psychomotor speed time were negative predictors of physical health quality.

CONCLUSIONS

In pwRRMS, cognitive dysfunctions such as response inhibition and intervention control, which are symptoms of attention deficit and impulsivity, have been shown to reduce the overall QoL. Among the strategies to reduce the impact of RRMS disease on patients' lives, it is essential to implement programs to prevent depression and increase cognitive reserve.

Prodromes in demyelinating disorders, amyotrophic lateral sclerosis, Parkinson disease, and Alzheimer's dementia

A prodrome is an early set of symptoms, which indicates the onset of a disease; these symptoms are often non-specific. Prodromal phases are now recognized in multiple central nervous system diseases. The depth of understanding of the prodromal phase varies across diseases, being more nascent for multiple sclerosis for example, than for Parkinson disease or Alzheimer's disease. Key challenges when identifying the prodromal phase of a disease include the lack of specificity of prodromal symptoms, and consequent need for accessible and informative biomarkers. Further, heterogeneity of the prodromal phase may be influenced by age, sex, genetics and other poorly understood factors. Nonetheless, recognition that an individual is in the prodromal phase of disease offers the opportunity for earlier diagnosis and with it the opportunity for earlier intervention.

Consensus statement of the Spanish Society of Neurology on the treatment of multiple sclerosis and holistic patient management in 2023

The last consensus statement of the Spanish Society of Neurology's Demyelinating Diseases Study Group on the treatment of multiple sclerosis (MS) was issued in 2016. Although many of the positions taken remain valid, there have been significant changes in the management and treatment of MS, both due to the approval of new drugs with different action mechanisms and due to the evolution of previously fixed concepts. This has enabled new approaches to specific situations such as pregnancy and vaccination, and the inclusion of new variables in clinical decision-making, such as the early use of high-efficacy disease-modifying therapies (DMT), consideration of the patient's perspective, and the use of such novel technologies as remote monitoring. In the light of these changes, this updated consensus statement, developed according to the Delphi method, seeks to reflect the new paradigm in the management of patients with MS, based on the available scientific evidence and the clinical expertise of the participants. The most significant recommendations are that immunomodulatory DMT be started in patients with radiologically isolated syndrome with persistent radiological activity, that patient perspectives be considered, and that the term "lines of therapy" no longer be used in the classification of DMTs (> 90% consensus). Following diagnosis of MS, the first DMT should be selected according to the presence/absence of factors of poor prognosis (whether epidemiological, clinical, radiological, or biomarkers) for the occurrence of new relapses or progression of disability; high-efficacy DMTs may be considered from disease onset.

Instability of excitatory synapses in experimental autoimmune encephalomyelitis and the outcome for excitatory circuit inputs to individual cortical neurons

Synapses are lost on a massive scale in the brain and spinal cord of people living with multiple sclerosis (PwMS), and this synaptic loss extends far beyond demyelinating lesions. Post-mortem studies show the long-term consequences of multiple sclerosis (MS) on synapses but do not inform on the early impacts of neuroinflammation on synapses that subsequently lead to synapse loss. How excitatory circuit inputs are altered across the dendritic tree of individual neurons under neuroinflammatory stress is not well understood. Here, we directly assessed the structural dynamics of labeled excitatory synapses in experimental autoimmune encephalomyelitis (EAE) as a model of immune-mediated cortical neuronal damage. We used in vivo two-photon imaging and a synthetic tissue-hydrogel super-resolution imaging technique to reveal the dynamics of excitatory synapses, map their location across the dendritic tree of individual neurons, and examine neurons at super-resolution for synaptic loss. We found that excitatory synapses are destabilized but not lost from dendritic spines in EAE, starting with the earliest imaging session before symptom onset. This led to dramatic changes in excitatory circuit inputs to individual cells. In EAE, stable synapses are replaced by synapses that appear or disappear across the imaging sessions or repeatedly change at the same location. These unstable excitatory inputs occur closer to one another in EAE than in healthy controls and are distributed across the dendritic tree. When imaged at super-resolution, we found that a small proportion of dendritic protrusions lost their presynapse and/or postsynapse. Our finding of diffuse destabilizing effects of neuroinflammation on excitatory synapses across cortical neurons may have significant functional consequences since normal dendritic spine dynamics and clustering are essential for learning and memory.

Association of the BDNF rs6265 Polymorphism with Cognitive Impairment in Multiple Sclerosis: A Case-Control Study in Mexican Patients

Cognition is a set of brain processes that allow the individual to interact with their environment. Multiple sclerosis (MS) is a chronic inflammatory disease that affects the cerebral white matter of the brain cortex and spinal cord, leading to cognitive impairment (CI) in 40-60% of the patients. Many studies have determined that CI is linked to genetic risk factors. We aimed to evaluate the association between BDNF gene rs6265 polymorphism and cognitive impairment in Mexican patients with MS by performing a case-control study. Mestizo-Mexican patients diagnosed with MS based on McDonald's criteria were enrolled. Cases were MS patients with CI (n = 31) while controls were MS patients without CI (n = 31). To measure cognitive functioning in MS patients, a neuropsychological screening battery for MS (NSB-MS) was used. Genotyping of the rs6265 gene variant was performed using quantitative real-time PCR (qPCR) with TaqMan probes. The results showed no statistically significant differences in sociodemographic and disease variables between case and control groups. qPCR analysis showed that there were 68% Val/Val wild-type homozygotes, 29% Val/Met polymorphic heterozygotes, and 3% Met/Met polymorphic homozygotes. The presence of BDNF gene rs6265 polymorphism showed an increased probability (3.6 times) of global cognitive impairment.

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.

Premorbid Sociodemographic Status and Multiple Sclerosis Outcomes in a Universal Health Care Context

Importance

Multiple sclerosis (MS) severity may be informed by premorbid sociodemographic factors.

Objective

To determine whether premorbid education, income, and marital status are associated with future MS disability and symptom severity, independent of treatment, in a universal health care context.

Design, Setting, and Participants

This nationwide observational cohort study examined data from the Swedish MS Registry linked to national population registries from 2000 to 2020. Participants included people with MS onset from 2005 to 2015 and of working age (aged 23 to 59 years) 1 year and 5 years preceding disease onset.

Exposures

Income quartile, educational attainment, and marital status measured at 1 and 5 years preceding disease onset.

Main Outcome and Measures

Repeated measures of Expanded Disability Status Scale (EDSS) scores and patient-reported Multiple Sclerosis Impact Scale (MSIS-29) scores. Models were adjusted for age, sex, relapses, disease duration, and treatment exposure. Secondary analyses further adjusted for comorbidity. All analyses were stratified by disease course (relapse onset and progressive onset).

Results

There were 4557 patients (mean [SD] age, 37.5 [9.3] years; 3136 [68.8%] female, 4195 [92.1%] relapse-onset MS) with sociodemographic data from 1-year preonset of MS. In relapse-onset MS, higher premorbid income and education correlated with lower disability (EDSS, -0.16 [95% CI, -0.12 to -0.20] points) per income quartile; EDSS, -0.47 [95% CI, -0.59 to -0.35] points if tertiary educated), physical symptoms (MSIS-29 physical subscore, -14% [95% CI, -11% to -18%] per income quartile; MSIS-29 physical subscore, -43% [95% CI, -35% to -50%] if tertiary educated), and psychological symptoms (MSIS-29 psychological subscore, -12% [95% CI, -9% to -16%] per income quartile; MSIS-29 psychological subscore, -25% [95% CI, -17% to -33%] if tertiary educated). Marital separation was associated with adverse outcomes (EDSS, 0.34 [95% CI, 0.18 to 0.51]; MSIS-29 physical subscore, 35% [95% CI, 12% to 62%]; MSIS-29 psychological subscore, 25% [95% CI, 8% to 46%]). In progressive-onset MS, higher income correlated with lower EDSS (-0.30 [95% CI, -0.48 to -0.11] points per income quartile) whereas education correlated with lower physical (-34% [95% CI, -53% to -7%]) and psychological symptoms (-33% [95% CI, -54% to -1%]). Estimates for 5-years preonset were comparable with 1-year preonset, as were the comorbidity-adjusted findings.

Conclusions and relevance

In this cohort study of working-age adults with MS, premorbid income, education, and marital status correlated with disability and symptom severity in relapse-onset and progressive-onset MS, independent of treatment. These findings suggest that socioeconomic status may reflect both structural and individual determinants of health in MS.

Multiple Sclerosis Pathogenesis and Updates in Targeted Therapeutic Approaches

PURPOSE OF REVIEW

In this review, we provide a comprehensive update on current scientific advances and emerging therapeutic approaches in the field of multiple sclerosis.

RECENT FINDINGS

Multiple sclerosis (MS) is a common disorder characterized by inflammation and degeneration within the central nervous system (CNS). MS is the leading cause of non-traumatic disability in the young adult population. Through ongoing research, an improved understanding of the disease underlying mechanisms and contributing factors has been achieved. As a result, therapeutic advancements and interventions have been developed specifically targeting the inflammatory components that influence disease outcome. Recently, a new type of immunomodulatory treatment, known as Bruton tyrosine kinase (BTK) inhibitors, has surfaced as a promising tool to combat disease outcomes. Additionally, there is a renewed interested in Epstein-Barr virus (EBV) as a major potentiator of MS. Current research efforts are focused on addressing the gaps in our understanding of the pathogenesis of MS, particularly with respect to non-inflammatory drivers. Significant and compelling evidence suggests that the pathogenesis of MS is complex and requires a comprehensive, multilevel intervention strategy. This review aims to provide an overview of MS pathophysiology and highlights the most recent advances in disease-modifying therapies and other therapeutic interventions.

Differential diagnosis of suspected multiple sclerosis: an updated consensus approach

Accurate diagnosis of multiple sclerosis requires careful attention to its differential diagnosis-many disorders can mimic the clinical manifestations and paraclinical findings of this disease. A collaborative effort, organised by The International Advisory Committee on Clinical Trials in Multiple Sclerosis in 2008, provided diagnostic approaches to multiple sclerosis and identified clinical and paraclinical findings (so-called red flags) suggestive of alternative diagnoses. Since then, knowledge of disorders in the differential diagnosis of multiple sclerosis has expanded substantially. For example, CNS inflammatory disorders that present with syndromes overlapping with multiple sclerosis can increasingly be distinguished from multiple sclerosis with the aid of specific clinical, MRI, and laboratory findings; studies of people misdiagnosed with multiple sclerosis have also provided insights into clinical presentations for which extra caution is warranted. Considering these data, an update to the recommended diagnostic approaches to common clinical presentations and key clinical and paraclinical red flags is warranted to inform the contemporary clinical evaluation of patients with suspected multiple sclerosis.

Microstructural changes precede depression in patients with relapsing-remitting Multiple Sclerosis

BACKGROUND

Multiple Sclerosis lesions in the brain and spinal cord can lead to different symptoms, including cognitive and mood changes. In this study we explore the temporal relationship between early microstructural changes in subcortical volumes and cognitive and emotional function in a longitudinal cohort study of patients with relapsing-remitting Multiple Sclerosis.

METHODS

In vivo imaging in forty-six patients with relapsing-remitting Multiple Sclerosis was performed annually over 3 years magnetic resonance imaging. Microstructural changes were estimated in subcortical structures using the free water fraction, a diffusion-based MRI metric. In parallel, patients were assessed with the Hospital Anxiety and Depression Scale amongst other tests. Predictive structural equation modeling was set up to further explore the relationship between imaging and the assessment scores. In a general linear model analysis, the cohort was split into patients with higher and lower depression scores.

RESULTS

Nearly all subcortical diffusion microstructure estimates at the baseline visit correlate with the depression score at the 2 years follow-up. The predictive nature of baseline free water estimates and depression subscores after 2 years are confirmed in the predictive structural equation modeling analysis with the thalamus showing the greatest effect size. The general linear model analysis shows patterns of MRI free water differences in the thalamus and amygdala/hippocampus area between participants with high and low depression score.

CONCLUSIONS

Our data suggests a relationship between higher levels of free-water in the subcortical structures in an early stage of Multiple Sclerosis and depression symptoms at a later stage of the disease.

A Predictive Autoantibody Signature in Multiple Sclerosis

Although B cells are implicated in multiple sclerosis (MS) pathophysiology, a predictive or diagnostic autoantibody remains elusive. Here, the Department of Defense Serum Repository (DoDSR), a cohort of over 10 million individuals, was used to generate whole-proteome autoantibody profiles of hundreds of patients with MS (PwMS) years before and subsequently after MS onset. This analysis defines a unique cluster of PwMS that share an autoantibody signature against a common motif that has similarity with many human pathogens. These patients exhibit antibody reactivity years before developing MS symptoms and have higher levels of serum neurofilament light (sNfL) compared to other PwMS. Furthermore, this profile is preserved over time, providing molecular evidence for an immunologically active prodromal period years before clinical onset. This autoantibody reactivity was validated in samples from a separate incident MS cohort in both cerebrospinal fluid (CSF) and serum, where it is highly specific for patients eventually diagnosed with MS. This signature is a starting point for further immunological characterization of this MS patient subset and may be clinically useful as an antigen-specific biomarker for high-risk patients with clinically- or radiologically-isolated neuroinflammatory syndromes.

Assessment of intelligence quotient in patients with neuromyelitis optica spectrum disease and multiple sclerosis

BACKGROUND

Cognitive impairment is common in people living with neuromyelitis optica spectrum disease (NMOSD) and multiple sclerosis (MS). However, there is little published data on intelligence quotient (IQ) in NMOSD patients. Therefore, we performed the present study to compare IQ scores across NMOSD, MS, and control groups.

METHOD

In this cross-sectional study, 49 NMOSD (30 with positive aquaporin4 antibody), 41 MS, and 20 control individuals were recruited. The IQ score for each person was measured using Wechsler Adult Intelligence Scale-Revised (WAIS-R). Participants were reported on eleven scores of subsets, verbal IQ (VIQ), performance IQ (PIQ), and full score IQ (FSIQ).

RESULT

The scores of FSIQ, VIQ, PIQ, vocabulary, similarities, and digit-symbol in NMOSD and MS individuals were lower than the control group. Relative to control, NMOSD patients reported a lower score of information. We found no difference between NMOSD and MS groups, except in vocabulary and similarities. No significant difference between seropositive and seronegative NMOSD groups was observed except for the information and block design. In NMOSD group, a greater EDSS score was associated with decreased scores of FSIQ, VIQ, and PIQ. Being employed and being married were associated with greater scores of VIQ and PIQ, respectively. In both NMOSD and MS groups, advanced education was associated with increased scores of FSIQ and VIQ.

CONCLUSION

Our study showed decreased IQ scores in NMOSD and MS. Further studies are required to examine intellectual quotient in people with NMOSD and MS.

Trail Making Test Could Predict Impairment in Cognitive Domains in Patients with Multiple Sclerosis: A Study of Diagnostic Accuracy

OBJECTIVE

Cognitive impairment (CI) and executive dysfunction (ED) are prevalent in patients with multiple sclerosis (PwMS). The Minimal Assessment of Cognitive Function in Multiple Sclerosis (MACFIMS) is the gold standard neuropsychological battery (NPB) for detecting CI. Delis-Kaplan Executive Function System (DKEFS) NPB evaluates ED. We aimed to find practical test(s) from DKEFS with acceptable diagnostic utility for early detection of impairment in cognitive and executive domains.

METHODS

Cognitive and executive tasks, physical disability, and depression scores of 30 PwMS were assessed (17 women, age: 38.1). Symbol Digit Modalities Test (SDMT), Paced Auditory Serial Addition Test (PASAT), and Controlled Oral Word Association Test (COWAT) from MACFIMS and Trail Making Test (TMT), Design Fluency Test (DFT), and Verbal Fluency Test (VFT) from DKEFS were selected. The association between patients' characteristics and performance in tests, and diagnostic accuracy of DKEFS tests in detecting impairment in cognitive tasks were evaluated, using Pearson correlation and receiver operator characteristic curve analyses, respectively.

RESULTS

A significant correlation was found between disease duration and SDMT and TMT subtests. Expanded Disability Status Scale was significantly related to SDMT, VFT-switching, and TMT subtests. Beck Depression Inventory was significantly related to DFT. TMT-switching detected abnormalities in SDMT and PASAT with 100% sensitivity, 93.3% (for SDMT), and 85.7% specificity (for PASAT). TMT-letter showed 100% sensitivity and 90% specificity in identifying abnormalities in COWAT.

CONCLUSIONS

TMT, particularly the switching condition, is a practical paper-based test that could predict impairment in cognitive tasks. Clinicians may use TMT as a screening tool among PwMS.

Brief international cognitive assessment for MS (BICAMS) and global brain volumes in early stages of MS - A longitudinal correlation study

BACKGROUND

Cognitive impairment is common in patients with multiple sclerosis, even in the early stages of the disease. The Brief International Cognitive Assessment for multiple sclerosis (BICAMS) is a short screening tool developed to assess cognitive function in everyday clinical practice.

OBJECTIVE

To investigate associations between volumetric brain measures derived from a magnetic resonance imaging (MRI) examination and performance on BICAMS subtests in early stages of multiple sclerosis (MS).

METHODS

BICAMS was used to assess cognitive function in 49 MS patients at baseline and after one and two years. The patients were separated into two groups (with or without cognitive impairment) based on their performances on BICAMSs subtests. MRI data were analysed by a software tool (MSMetrix), yielding normalized measures of global brain volumes and lesion volumes. Associations between cognitive tests and brain MRI measures were analysed by running correlation analyses, and differences between subgroups and changes over time with independent and paired samples tests, respectively.

RESULTS

The strongest baseline correlations were found between the BICAMS subtests and normalized whole brain volume (NBV) and grey matter volume (NGV); processing speed r = 0.54/r = 0.48, verbal memory r = 0.49/ r = 0.42, visual memory r = 0.48 /r = 0.39. Only the verbal memory test had significant correlations with T2 and T1 lesion volumes (LV) at both time points; T2LV r = 0.39, T1LV r = 0.38. There were significant loss of grey matter and white matter volume overall (NGV p<0.001, NWV p = 0.003), as well as an increase in T1LV (p = 0.013). The longitudinally defined confirmed cognitively impaired (CCI) and preserved (CCP) patients showed significant group differences on all MRI volume measures at both time points, except for NWV. Only the CCI subgroup showed significant white matter atrophy (p = 0.006) and increase in T2LV (p = 0.029).

CONCLUSIONS

The present study found strong correlations between whole brain and grey matter volumes and performance on the BICAMS subtests as well as significant changes in global volumes from baseline to follow-up with clear differences between patients defined as cognitively impaired and preserved at both baseline and follow-up.

The CELLO trial: Protocol of a planned phase 4 study to assess the efficacy of Ocrelizumab in patients with radiologically isolated syndrome

BACKGROUND

Patients with radiologically isolated syndrome (RIS) exhibit CNS lesions suggestive of multiple sclerosis (MS) in the absence of overt neurological symptoms characteristic of the disease. They may have concurrent brain atrophy, subtle cognitive impairment, and intrathecal inflammation. At least half ultimately develop MS, cementing RIS as preclinical MS for many. However, high-quality data, including immunologic biomarkers, to guide treatment decisions in this population are lacking. Early intervention with ocrelizumab, a humanized monoclonal antibody approved for relapsing and primary progressive MS that targets CD20+ B-cells, may affect disease course and improve long-term outcomes. The objective of this study is to describe the protocol for CELLO, a clinical trial assessing the effect of ocrelizumab on RIS.

METHODS

The CELLO clinical trial, a phase 4, multicenter, randomized, double-blind, placebo-controlled study conducted as an academic-industry collaboration, aims to (1) assess the efficacy of ocrelizumab in patients with RIS and (2) identify biomarkers indicative of emerging autoimmunity as well as immune recovery after transient B-cell depletion. The study will enroll 100 participants across ≥15 sites. Participants will be aged 18 to 40 years, have RIS (defined as meeting 2017 revised McDonald criteria for dissemination in space), and have either been diagnosed with RIS within the last 5 years or have had new brain lesions identified within 5 years of study entry. A screening program of first-degree relatives of patients with MS will be used to boost recruitment. Eligible patients will be randomized 1:1 to receive 3 courses of ocrelizumab or placebo at baseline, week 24, and week 48. Patients will subsequently be followed up for ≥3 years. The primary outcome is time to development of new radiological or clinical evidence of MS. Secondary and exploratory objectives will investigate neuroimaging, serological and immunologic biomarkers, cognitive function, and patient-reported outcomes. A substudy using single-cell RNA sequencing to characterize blood and CSF immune cells will assess markers associated with conversion to clinical MS.

CONCLUSION

The CELLO study will improve the understanding of B-cell biology in early MS disease pathophysiology, characterize the emergence of CNS autoimmunity, and provide evidence to inform treatment decision-making for individuals with RIS.

CLINICALTRIALS

GOV: NCT04877457.

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.

Mortality and cause of death in multiple sclerosis in western Norway 1950-2021: a registry-based linkage study

BACKGROUND

Persons with multiple sclerosis (pwMS) have higher risk of mortality compared with the general population. Longitudinal studies are important for understanding the evolution of survival in pwMS.

OBJECTIVE

Examine changes in mortality among pwMS during the past seven decades.

METHODS

We followed pwMS from Hordaland and Møre and Romsdal in Western Norway, with disease onset from before 1950, identified from population-based epidemiological surveys and the Norwegian MS Registry and Biobank, until 1 January 2021. Data were linked to the Norwegian Cause of Death Registry to obtain underlying cause of death. We examined all-cause, and cause-specific mortality using standardised mortality ratios (SMR) and excess death rates (EDR). We calculated life expectancies and assessed survival stratified by sex, age and disease phenotype at onset. We compared hazard ratios (HRs) for mortality, in pwMS diagnosed before and after the era of disease-modifying treatment (DMT).

RESULTS

Of 3624 pwMS, 964 (55.5% women) had died, predominantly of multiple sclerosis (49.0%). Median life expectancy for pwMS was 74.3 years (95% CI 73.3 to 75.3), compared with 83.1 years for the general population (p<0.001). From disease onset, pwMS survived 14.6 years shorter than the general population (p<0.001). Overall, SMR was 2.3 (95% CI 2.13 to 2.42) and EDR was 6.8 (95% CI 6.42 to 7.09) for pwMS. Treatment-eligible pwMS diagnosed in the DMT era had the lowest risk of mortality, HR 0.49 (95% CI 0.34 to 0.70,p<0.001).

CONCLUSION

Excess mortality among pwMS declined during the past seven decades, possibly due to improved diagnostics, better symptomatic treatment and access to DMTs.

From the prodromal stage of multiple sclerosis to disease prevention

A prodrome is an early set of signs or symptoms that indicate the onset of a disease before more typical symptoms develop. Prodromal stages are well recognized in some neurological and immune-mediated diseases such as Parkinson disease, schizophrenia, type 1 diabetes mellitus and rheumatoid arthritis. Emerging evidence indicates that a prodromal stage exists in multiple sclerosis (MS), raising the possibility of intervention at this stage to delay or prevent the development of classical MS. However, much remains unclear about the prodromal stage of MS and considerable research is needed to fully characterize the prodrome and develop standardized criteria to reliably identify individuals with prodromal MS who are at high risk of progressing to a diagnosis of MS. In this Roadmap, we draw on work in other diseases to propose a disease framework for MS that incorporates the prodromal stage, and set out key steps and considerations needed in future research to fully characterize the MS prodrome, identify early disease markers and develop standardized criteria that will enable reliable identification of individuals with prodromal MS, thereby facilitating trials of interventions to slow or stop progression beyond the prodrome.

Axonal injury in asymptomatic individuals preceding onset of multiple sclerosis

Axonal loss is the main cause of irreversible disability in multiple sclerosis (MS). Serum neurofilament light (sNfL) is a biomarker of axonal disintegration. In this nested case-control study, blood samples from 519 presymptomatic persons (age range 4-39 years) who later received an MS diagnosis showed higher sNfL concentrations than 519 matched controls (p < 0.0001), noticeable at least 10 years before clinical MS onset. Mean values for pre-MS and control groups were 9.6 pg/mL versus 7.4 pg/mL 0-5 years before onset, and 6.4 pg/mL versus 5.8 pg/mL 5-10 years before onset. These results support that axonal injury occurs early in MS pathogenesis.

Preventing disease progression in multiple sclerosis-insights from large real-world cohorts

Multiple sclerosis is a chronic neuroinflammatory disease with a highly heterogeneous disease course. Preventing lasting disability requires early identification of persons at risk and novel approaches towards patient stratification for personalized treatment decisions. In this comment, we discuss the importance of large datasets of real-world cohorts in order to address this unmet need.

Secondary Prevention in Radiologically Isolated Syndromes and Prodromal Stages of Multiple Sclerosis

Following the extraordinary progress in the treatment of multiple sclerosis (MS), two major unmet needs remain: understanding the etiology of the disease and, hence, designing definitive cures (this perspective is neither at hand, nor it can be taken for granted that the etiologic targets will be readily treatable); the prevention of an overt and disabling disease, which seems to be a more realistic and pragmatic perspective, as the integration of genetic data with endophenotypes, MRI, and other biomarkers ameliorates our ability to identify early neuroinflammation. Radiologically isolated syndrome (RIS; diagnosed when the unanticipated MRI finding of brain spatial dissemination of focal white matter lesions highly suggestive of MS occurs in subjects without symptoms of MS, and with normal neurological examinations) and the recently focused “prodromal MS” are conditions at risk of conversion toward overt disease. Here, we explore the possibility of secondary prevention approaches in these early stages of neuroinflammation. RIS and prodromal MS are rare conditions, which suggest the importance of Study Groups and Disease Registry to implement informative clinical trials. We summarize ongoing preventive approaches in the early stages of the demyelinating process, especially in RIS conditions. Moreover, we highlight the importance of the biomarkers and the predictors of evolution to overt disease, which may be useful to select the individuals at risk of conversion to clinically isolated syndrome (CIS) and/or clinically definite MS. Finally, we illustrate the importance of the endophenotypes to test the frontline immunomodulatory approach for preventive strategies. Future investigations, especially in relatives of patients, based on MRI techniques and biological studies (better with integrated approaches) may provide opportunities to understand the MS early causal cascade and may help to identify a “therapeutic window” to potentially reverse early disease processes.

Strong tuberculin response after BCG vaccination is associated with low multiple sclerosis risk: a population-based cohort study

Background

Multiple sclerosis (MS) is characterized by inflammatory lesions in the central nervous system involving pro-inflammatory T-cells. Immune dysregulation is well described in prevalent disease, but it is not known whether this precedes disease development. Bacillus Calmette–Guérin (BCG) vaccination ameliorates MS-like disease in mice. In people vaccinated with BCG, the tuberculin skin test (TST) offers a standardized measure of a T-cell-mediated immune response. We therefore hypothesized that the strength of the TST response after BCG vaccination is associated with subsequent MS risk.

Methods

Using data from a Norwegian tuberculosis screening programme (1963–1975), we designed a population-based cohort study and related the size of TST reactions in individuals previously vaccinated with BCG to later MS disease identified through the Norwegian MS registry. We fitted Cox proportional hazard models and flexible parametric survival models to investigate the association between TST reactivity, MS risk and its temporal relationship.

Results

Among 279 891 participants (52% females), 679 (69% females) later developed MS. Larger TST reactivity was associated with decreased MS risk. The hazard ratio for MS per every 4-mm increase in skin induration size was 0.86 (95% confidence interval 0.76–0.96) and similar between sexes. The strength of the association persisted for &gt;30 years after the TST.

Conclusion

A strong in vivo vaccine response to BCG is associated with reduced MS risk &gt;30 years later. The immunological mechanisms determining TST reactivity suggest that skewed T-cell-mediated immunity precedes MS onset by many decades.

Pathways to cures for multiple sclerosis: A research roadmap

Background:

Multiple Sclerosis (MS) is a growing global health challenge affecting nearly 3 million people. Progress has been made in the understanding and treatment of MS over the last several decades, but cures remain elusive. The National MS Society is focused on achieving cures for MS.

Objectives:

Cures for MS will be hastened by having a roadmap that describes knowledge gaps, milestones, and research priorities. In this report, we share the Pathways to Cures Research Roadmap and recommendations for strategies to accelerate the development of MS cures.

Methods:

The Roadmap was developed through engagement of scientific thought leaders and people affected by MS from North America and the United Kingdom. It also included the perspectives of over 300 people living with MS and was endorsed by many leading MS organizations.

Results:

The Roadmap consist of three distinct but overlapping cure pathways: (1) stopping the MS disease process, (2) restoring lost function by reversing damage and symptoms, and (3) ending MS through prevention. Better alignment and focus of global resources on high priority research questions are also recommended.

Conclusions:

We hope the Roadmap will inspire greater collaboration and alignment of global resources that accelerate scientific breakthroughs leading to cures for MS.

The Multiple Sclerosis Prodrome: Evidence to Action

A growing body of work points toward the existence of a clinically symptomatic prodromal phase in multiple sclerosis (MS) that might span 5–10 years or more. A prodrome is an early set of signs or symptoms predating the onset of classical disease, which in turn predates a definitive diagnosis. Evidence for a prodromal phase in MS could have major implications for prevention, earlier recognition and treatment, as well as an improved disease course or prognosis. This Perspective provides a succinct overview of the recent advances in our understanding of the MS prodrome and current key challenges. Many of the MS prodromal features characterized thus far are non-specific and are common in the general population; no single feature alone is sufficient to identify an individual with prodromal MS. Biomarkers may increase specificity and accuracy for detecting individuals in the MS prodromal phase, but are yet to be discovered or formally validated. Progress made in the elucidation of prodromal phases in other neurological and immune-mediated diseases suggests that these barriers can be overcome. Therefore, while knowledge of a prodromal phase in MS remains nascent, how best to move from the rapidly growing evidence to research-related action is critical. Immediate implications include refining the concept of the MS continuum to include a prodromal phase. This will help inform the true “at risk” period when considering exposures that might cause MS. Major long-term implications include the earlier recognition of MS, improved prognosis, through earlier disease management, and the future possibility of MS disease prevention.

Reduction in cognitive processing speed surrounding multiple sclerosis relapse

Objective

The purpose of this study was to explore the longitudinal relationship between multiple sclerosis (MS) relapses and information processing efficiency among persons with relapsing–remitting MS.

Methods

We conducted a Swedish nationwide cohort study of persons with incident relapsing–remitting MS (2001–2019). Relapse information and symbol digit modalities test (SDMT) scores were obtained from the Swedish MS Registry. Follow‐up was categorized into 2 periods based on relapse status: “relapse” (90 days pre‐relapse to 730 days post‐relapse, subdivided into 10 periods) and “remission.” Linear mixed models compared SDMT scores during the relapse periods to SDMT scores recorded during remission (reference) with results reported as β‐coefficients and 95% confidence intervals (CIs), adjusted for age, sex, SDMT type (written vs oral), time‐varying, disease‐modifying therapy exposure and sequence of SDMT.

Results

Over a mean (SD) follow‐up of 10.7 (4.3) years, 31,529 distinct SDMTs were recorded among 3,877 persons with MS. There was a significant decline in information processing efficiency that lasted from 30 days pre‐relapse up to 550 days post‐relapse, with the largest decline occurring 0 to 30 days post‐relapse (β‐coefficient: −4.00 (95% CI = −4.61 to −3.39), relative to the period of remission.

Interpretation

We found evidence of cognitive change up to 1 month prior to relapse onset. The reduction in SDMT lasted 1.5 years and was clinically significant up to 3 months post‐relapse. These results suggest that the effects of a relapse on cognition are longer than previously thought and highlight the importance of reducing relapse rates as a potential means of preserving cognitive function. ANN NEUROL 2022;91:417–423

Remote self-administration of digital cognitive tests using the Brief Assessment of Cognition: Feasibility, reliability, and sensitivity to subjective cognitive decline

Cognitive impairment is a common and pervasive feature of etiologically diverse disorders of the central nervous system, and a target indication for a growing number of symptomatic and disease modifying drugs. Remotely acquired digital endpoints have been recognized for their potential in providing frequent, real-time monitoring of cognition, but their ultimate value will be determined by the reliability and sensitivity of measurement in the populations of interest. To this end, we describe initial validation of remote self-administration of cognitive tests within a regulatorily compliant tablet-based platform. Participants were 61 older adults (age 55+), including 20 individuals with subjective cognitive decline (SCD). To allow comparison between remote (in-home) and site-based testing, participants completed 2 testing sessions 1 week apart. Results for three of four cognitive domains assessed demonstrated equivalence between remote and site-based tests, with high cross-modality ICCs (absolute agreement) for Symbol Coding (ICC = 0.75), Visuospatial Working Memory (ICC = 0.70) and Verbal Fluency (ICC > 0.73). Group differences in these domains were significant and reflected sensitivity to objective cognitive impairment in the SCD group for both remote and site-based testing (p < 0.05). In contrast, performance on tests of verbal episodic memory suggested inflated performance during unmonitored testing and indicate reliable use of remote cognitive assessments may depend on the construct, as well as the population being tested.

Subcortical volumes as early predictors of fatigue in multiple sclerosis

OBJECTIVE

Fatigue is a frequent and severe symptom in multiple sclerosis (MS), but its pathophysiological origin remains incompletely understood. We aimed to examine the predictive value of subcortical gray matter volumes for fatigue severity at disease onset and after four years by applying structural equation modeling (SEM).

METHODS

This multi-center cohort study included 601 treatment-naive MS patients after the first demyelinating event. All patients underwent a standardized 3T MRI protocol. A subgroup of 230 patients with available clinical follow-up data after four years was also analyzed. Associations of subcortical volumes (included into SEM) with MS-related fatigue were studied regarding their predictive value. In addition, subcortical regions that have a central role in the brain network (hubs) were determined through structural covariance network (SCN) analysis.

RESULTS

Predictive causal modeling identified volumes of the caudate (s [standardized path coefficient]=0.763, p=0.003 [left]; s=0.755, p=0.006 [right]), putamen (s=0.614, p=0.002 [left]; s=0.606, p=0.003 [right]) and pallidum (s=0.606, p=0.012 [left]; s=0.606, p=0.012 [right]) as prognostic factors for fatigue severity in the cross-sectional cohort. Moreover, the volume of the pons was additionally predictive for fatigue severity in the longitudinal cohort (s=0.605, p=0.013). In the SCN analysis, network hubs in patients with fatigue worsening were detected in the putamen (p=0.008 [left]; p=0.007 [right]) and pons (p=0.0001).

INTERPRETATION

We unveiled predictive associations of specific subcortical gray matter volumes with fatigue in an early and initially untreated MS cohort. The colocalization of these subcortical structures with network hubs suggests an early role of these brain regions in terms of fatigue evolution. This article is protected by copyright. All rights reserved.

The multiple sclerosis prodrome

A prodrome is an early set of signs, symptoms or other findings that occur before the onset of typical symptoms of a disease. Prodromal phases are well recognized in several neurological and inflammatory diseases, but the possibility of a prodrome in multiple sclerosis (MS) has received relatively little attention until the past few years. In this Perspective, we summarize what is currently known about the MS prodrome, including its possible duration, clinical features and potential biomarkers. We also consider what insights and lessons can be learned from knowledge of and research into the prodromal phases of other diseases. A better understanding of the MS prodrome could have profound clinical implications as it could enable earlier recognition of MS and earlier initiation of treatments that reduce relapse rates and long-term disability. Knowledge of the MS prodrome could also affect research into the causes of MS, and putative risk factors must be re-evaluated in light of the MS prodrome. We conclude by outlining the major knowledge gaps and propose future initiatives.

Defining the prodromal phase of multiple sclerosis based on healthcare access in a Portuguese population - ProdMS study

BACKGROUND

Multiple sclerosis (MS) is a chronic immune-mediated disease of the central nervous system. Prodromal symptoms and higher healthcare use have been suggested in patients who later develop MS.

OBJECTIVES

Assess the healthcare utilization pattern of relapsing-remitting MS (RRMS) patients in the five years prior to MS diagnosis.

METHODS

Retrospective, multicentric study. Demographic and clinical data, drug prescriptions and diagnostic tests were collected from electronic health records five-years previous to MS diagnosis and compared with national data.

RESULTS

Included 168 patients, 112 (66.7%) female, median age 34±11 years. The mean number of healthcare use per patient per year was 3.14±2,69, most of them in primary healthcare (47%). Most frequent symptoms were musculoskeletal (22%), gastrointestinal (17%), sensitive (14%) and sensory organs (14%). Median number of diagnostic tests per patient was 6 (IQR 7), and drug prescriptions per patient was 6 (IQR 9). Most frequently prescribed drugs were analgesic/anti-inflammatories, antibiotics and anxiolytics and there was a high request rate of MRIs.

CONCLUSION

RRMS patients had a high frequency of healthcare utilization when compared to national data. This supports the current evidence showing a prodromal phase in MS.

No significant differences in absenteeism or academic achievements in a Norwegian multiple sclerosis case control study

BACKGROUND

The duration and features of the multiple sclerosis (MS) prodrome are not well defined. We aimed to ascertain whether people with a future MS diagnosis have more days of absence and perform worse in upper secondary school than age, gender and county-matched controls.

METHODS

Using registry data from the southeast of Norway, we identified people with MS born ≥1978. Statistics Norway provided information on grades and days of absence in cases and matched controls. We looked at absence in the three years of upper secondary school and grades in the compulsory subjects Norwegian, English, mathematics and physical education.

RESULTS

We identified 107 cases with disease onset one year or more after graduation and 626 controls. There were no significant differences in absence or grades achieved in the population as a whole or in those with disease onset within four years of diagnosis, and no association between time to disease onset and days of absence or grades.

CONCLUSION

There was no difference in days of absence or grades achieved in upper secondary school in the four years leading up to disease onset in cases compared to controls. A potential prodrome may not affect cognition enough to impact school achievements.

Exposure to breastfeeding and risk of developing multiple sclerosis

BACKGROUND

Early-life factors are reported to modulate the risk of developing multiple sclerosis (MS) among adults. The association between exposure to breastfeeding and the risk of MS is debated. We aimed to disclose whether past exposure to breastfeeding and its duration are associated with the risk of developing MS.

METHODS

We used a cohort design linking prospectively collected information on breastfeeding from the Cohort of Norway community-based surveys on health status (CONOR) with the Norwegian MS Registry and the population-based Medical Birth Registry of Norway that includes information on all births in Norway since 1967. MS clinical onset was collected throughout 2016. A total of 95 891 offspring born between 1922 and 1986 to mothers participating in CONOR were included. We identified 215 offspring within this cohort who developed adult-onset MS. Associations between breastfeeding and MS risk were estimated as hazard ratios using Cox proportional hazard models adjusting for maternal factors including education.

RESULTS

We found no association between having been breastfed for ≥4 months and MS risk, also after adjusting for various maternal factors (hazard ratio = 0.90; 95% confidence interval 0.68-1.19). The estimates did not change for different durations of breastfeeding. The results were similar when adjusting for other perinatal factors.

CONCLUSION

Our study could not confirm previous findings of an association between breastfeeding and risk of MS. Breastfeeding information was less likely to be biased by knowledge of disease compared with case-control studies.

Onset Symptom Clusters in Multiple Sclerosis: Characteristics, Comorbidities, and Risk Factors

Background: Multiple sclerosis (MS) symptoms are expected to aggregate in specific patterns across different stages of the disease. Here, we studied the clustering of onset symptoms and examined their characteristics, comorbidity patterns and associations with potential risk factors.

Methods: Data stem from the Swiss Multiple Sclerosis Registry, a prospective study including 2,063 participants by November 2019. MS onset symptoms were clustered using latent class analysis (LCA). The latent classes were further examined using information on socio-demographic characteristics, MS-related features, potential risk factors, and comorbid diseases.

Results: The LCA model with six classes (frequencies ranging from 12 to 24%) was selected for further analyses. The latent classes comprised a multiple symptoms class with high probabilities across several symptoms, contrasting with two classes with solitary onset symptoms: vision problems and paresthesia. Two gait classes emerged between these extremes: the gait-balance class and the gait-paralysis class. The last class was the fatigue-weakness-class, also accompanied by depression symptoms, memory, and gastro-intestinal problems. There was a moderate variation by sex and by MS types. The multiple symptoms class yielded increased comorbidity with other autoimmune disorders. Similar to the fatigue-weakness class, the multiple symptoms class showed associations with angina, skin diseases, migraine, and lifetime prevalence of smoking. Mononucleosis was more frequently reported in the fatigue-weakness and the paresthesia class. Familial aggregation did not differ among the classes.

Conclusions: Clustering of MS onset symptoms provides new perspectives on the heterogeneity of MS. The clusters comprise different potential risk factors and comorbidities. They point toward different risk mechanisms.

Neurodegeneration in Multiple Sclerosis: Symptoms of Silent Progression, Biomarkers and Neuroprotective Therapy-Kynurenines Are Important Players

Neurodegeneration is one of the driving forces behind the pathogenesis of multiple sclerosis (MS). Progression without activity, pathopsychological disturbances (cognitive impairment, depression, fatigue) and even optic neuropathy seems to be mainly routed in this mechanism. In this article, we aim to give a comprehensive review of the clinical aspects and symptomology, radiological and molecular markers and potential therapeutic targets of neurodegeneration in connection with MS. As the kynurenine pathway (KP) was evidenced to play an important role in the pathogenesis of other neurodegenerative conditions (even implied to have a causative role in some of these diseases) and more and more recent evidence suggest the same central role in the neurodegenerative processes of MS as well, we pay special attention to the KP. Metabolites of the pathway are researched as biomarkers of the disease and new, promising data arising from clinical evaluations show the possible therapeutic capability of KP metabolites as neuroprotective drugs in MS. Our conclusion is that the kynurenine pathway is a highly important route of research both for diagnostic and for therapeutic values and is expected to yield concrete results for everyday medicine in the future.

Maternal education has significant influence on progression in multiple sclerosis

OBJECTIVE

The identification of potential risk factors for disease severity is of great importance in the treatment of multiple sclerosis. The influence of socioeconomic status on progression in multiple sclerosis (MS) is sparsely investigated. Our aim was to investigate how socioeconomic status in adolescence influences disease progression in later life.

METHODS

A total of 1598 patients with multiple sclerosis from a well-defined population in Norway were included. Detailed information on disease progression, measured by expanded disability status scale (EDSS) and multiple sclerosis severity score (MSSS), were combined with data on socioeconomic factors. We used residency and parental level of education at patients' age 16 and exposure to second-hand smoking as a measure of socioeconomic status in adolescence, adjusting for the same variables as well as use of disease modifying treatments at prevalence date 01.01.18.

RESULTS

High maternal level of education at patients' age 16 was significantly associated with less pronounced disease progression measured by MSSS (β-coefficient -0.58, p = 0.015), younger age and lower EDSS at disease onset, and shorter time from onset to diagnosis. No significant associations were found for paternal education level and MSSS. The use of any disease modifying treatment before prevalence date was significantly associated with disease progression (β-coefficient -0.49, p=0.004), while residence, current and second-hand smoking were not.

CONCLUSION

This study on a population-based, real-world cohort shows that the parental level of education has a significant impact on a timely diagnosis of MS. In addition to disease modifying treatment, maternal level of education also had an impact on disease progression in later life.

Reliability, construct and concurrent validity of a smartphone-based cognition test in multiple sclerosis

Background:

Early detection and monitoring of cognitive dysfunction in multiple sclerosis (MS) may be enabled with smartphone-adapted tests that allow frequent measurements in the everyday environment.

Objectives:

The aim of this study was to determine the reliability, construct and concurrent validity of a smartphone-adapted Symbol Digit Modalities Test (sSDMT).

Methods:

During a 28-day follow-up, 102 patients with MS and 24 healthy controls (HC) used the MS sherpa^® app to perform the sSDMT every 3 days on their own smartphone. Patients performed the Brief International Cognitive Assessment for MS at baseline. Test–retest reliability (intraclass correlation coefficients, ICC), construct validity (group analyses between cognitively impaired (CI), cognitively preserved (CP) and HC for differences) and concurrent validity (correlation coefficients) were assessed.

Results:

Patients with MS and HC completed an average of 23.2 (SD = 10.0) and 18.3 (SD = 10.2) sSDMT, respectively. sSDMT demonstrated high test–retest reliability (ICCs > 0.8) with a smallest detectable change of 7 points. sSDMT scores were different between CI patients, CP patients and HC (all ps < 0.05). sSDMT correlated modestly with the clinical SDMT (highest r = 0.690), verbal (highest r= 0.516) and visuospatial memory (highest r= 0.599).

Conclusion:

Self-administered smartphone-adapted SDMT scores were reliable and different between patients who were CI, CP and HC and demonstrated concurrent validity in assessing information processing speed.

Isolated Cognitive Decline in Neurologically Stable Patients with Multiple Sclerosis

(1) Background: Cognitive deterioration is an important marker of disease activity in multiple sclerosis (MS). It is vital to detect cognitive decline as soon as possible. Cognitive deterioration can take the form of isolated cognitive decline (ICD) with no other clinical signs of disease progression present. (2) Methods: We investigated 1091 MS patients from the longitudinal GQ (Grant Quantitative) study, assessing their radiological, neurological, and neuropsychological data. Additionally, the confirmatory analysis was conducted. Clinical disease activity was defined as the presence of new relapse or disability worsening. MRI activity was defined as the presence of new or enlarged T2 lesions on brain MRI. (3) Results: Overall, 6.4% of patients experienced cognitive decline and 4.0% experienced ICD without corresponding clinical activity. The vast majority of cognitively worsening patients showed concomitant progression in other neurological and radiologic measures. There were no differences in disease severity between completely stable patients and cognitively worsening patients but with normal cognition at baseline. (4) Conclusions: Only a small proportion of MS patients experience ICD over short-term follow-up. Patients with severe MS are more prone to cognitive decline; however, patients with normal cognitive performance and mild MS might benefit from the early detection of cognitive decline the most.

Brain atrophy and clinical characteristics predicting SDMT performance in multiple sclerosis: A 10-year follow-up study

Objectives

To identify Magnetic Resonance Imaging (MRI), clinical and demographic biomarkers predictive of worsening information processing speed (IPS) as measured by Symbol Digit Modalities Test (SDMT).

Methods

Demographic, clinical data and 1.5 T MRI scans were collected in 76 patients at time of inclusion, and after 5 and 10 years. Global and tissue-specific volumes were calculated at each time point. For the primary outcome of analysis, SDMT was used.

Results

Worsening SDMT at 5-year follow-up was predicted by baseline age, Expanded Disability Status Scale (EDSS), SDMT, whole brain volume (WBV) and T2 lesion volume (LV), explaining 30.2% of the variance of SDMT. At 10-year follow-up, age, EDSS, grey matter volume (GMV) and T1 LV explained 39.4% of the variance of SDMT change.

Conclusion

This longitudinal study shows that baseline MRI-markers, demographic and clinical data can help predict worsening IPS. Identification of patients at risk of IPS decline is of importance as follow-up, treatment and rehabilitation can be optimized.

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.

A two-year longitudinal follow-up of cognitive performance assessed by BICAMS in newly diagnosed patients with MS

BACKGROUND

Cognitive impairment is common in patients with multiple sclerosis (MS) and may occur at any stage and with any subtype of the disease. Screening and monitoring of cognitive function should therefore be implemented into everyday clinical neurology practice. The Brief International Cognitive Assessment for Multiple Sclerosis (BICAMS) was developed for this purpose. Although several cross-sectional studies have validated BICAMS, longitudinal studies evaluating its use as part of a clinical follow-up routine are still lacking.

OBJECTIVE

To investigate cognitive function and trajectories of change assessed by the BICAMS test battery in a cohort of newly diagnosed relapsing-remitting MS (RRMS) patients examined at baseline and after 12 and 24 months.

METHODS

BICAMS was used to assess cognitive function in 58 RRMS patients, who also filled in the Hospital Anxiety and Depression Scale (HADS) and the Fatigue Scale for Motor and Cognitive Functions (FSMC), and underwent standard neurological evaluations at baseline and at the two follow-ups.

RESULTS

A total of 27 patients (46.6%) were defined as cognitively impaired at baseline on at least one test, and 22 (37.9%) were defined as impaired at follow-up after 24 months. Throughout the study, 8 (13.8%) and 4 (6.9%) patients were consistently defined as impaired on two or three tests, respectively. The mean raw scores on two BICAMS subtests (SDMT and CVLT-II) improved significantly from baseline to the first follow-up, and then remained stable the next year, whereas the visual memory test (BVMT-R) were overall unchanged from baseline to the end of the study. The correlations between the scores on HADS, FSMC and the BICAMS subtests were non-significant at baseline, but weak to moderate negative correlations were found at the one- and two-year follow-ups.

CONCLUSION

The patients showed improved test results from baseline to the first follow-up examination, indicating that an effect of previous practise should be taken into account when interpreting the results. With results showing both trajectories of stability and change, our study supported the validity of including BICAMS as part of a clinical follow-up routine of RRMS patients. Anxiety, depression, fatigue and cognition should always be assessed at the same time to reveal interaction effects that are expected to affect the daily-life functioning of at least some of the RRMS patients.

Serum Neurofilament Light Chain Levels in Patients With Presymptomatic Multiple Sclerosis

Importance

Unrecognized demyelinating events often precede the clinical onset of multiple sclerosis (MS). Identification of these events at the time of occurrence would have implications for early diagnosis and the search of causal factors for the disease.

Objective

To assess whether serum neurofilament light chain (sNfL) levels are elevated before the clinical MS onset.

Design, Setting, and Participants

Nested case-control study among US military personnel who have serum samples stored in the US Department of Defense Serum Repository. Serum samples were collected from 2000 to 2011; sNfL assays and data analyses were performed from 2018 to 2019. We selected 60 case patients with MS who either had 2 samples collected before onset (mean follow-up, 6.3 years) or 1 sample collected before and 1 after onset (mean follow-up, 1.3 years), among 245 previously identified case patients. For each case, we randomly selected 1 of 2 previously identified control individuals matched by age, sex, race/ethnicity, and dates of sample collection. The sample size was chosen based on the available funding.

Exposures

Serum NfL concentrations measured using an ultrasensitive single-molecule array assay (Simoa).

Main Outcomes and Measurements

Log-transformed sNfL concentrations in case patients and control individuals compared using conditional logistic regression and linear mixed models.

Results

Mean age at baseline was 27.5 years, and 92 of 120 participants (76.7%) were men. Serum NfL levels were higher in case patients with MS compared with their matched control individuals in samples drawn a median of 6 years (range, 4-10 years) before the clinical onset (median, 16.7 pg/mL; interquartile range [IQR], 12.6-23.1 pg/mL vs 15.2 pg/m; IQR, 10.3-19.9 pg/mL; P = .04). This difference increased with decreasing time to the case clinical onset (estimated coefficient for interaction with time = 0.063; P = .008). A within-person increase in presymptomatic sNfL levels was associated with higher MS risk (rate ratio for ≥5 pg/mL increase, 7.50; 95% CI, 1.72-32.80). The clinical onset was associated with a marked increase in sNfL levels (median, 25.0; IQR, 17.1-41.3 vs 45.1; IQR, 27.0-102.7 pg/mL for presymptomatic and postonset MS samples; P = .009).

Conclusions and Relevance

The levels of sNfL were increased 6 years before the clinical MS onset, indicating that MS may have a prodromal phase lasting several years and that neuroaxonal damage occurs already during this phase.

Cognitive impairment in multiple sclerosis: clinical management, MRI, and therapeutic avenues

Multiple sclerosis is a chronic, demyelinating disease of the CNS. Cognitive impairment is a sometimes neglected, yet common, sign and symptom with a profound effect on instrumental activities of daily living. The prevalence of cognitive impairment in multiple sclerosis varies across the lifespan and might be difficult to distinguish from other causes in older age. MRI studies show that widespread changes to brain networks contribute to cognitive dysfunction, and grey matter atrophy is an early sign of potential future cognitive decline. Neuropsychological research suggests that cognitive processing speed and episodic memory are the most frequently affected cognitive domains. Narrowing evaluation to these core areas permits brief, routine assessment in the clinical setting. Owing to its brevity, reliability, and sensitivity, the Symbol Digit Modalities Test, or its computer-based analogues, can be used to monitor episodes of acute disease activity. The Symbol Digit Modalities Test can also be used in clinical trials, and data increasingly show that cognitive processing speed and memory are amenable to cognitive training interventions.