Disparities by Race in Pregnancy Care and Clinical Outcomes in Women With Multiple Sclerosis: A Diverse Multicenter Cohort

BACKGROUND AND OBJECTIVES: Racial disparities exist in both neurologic and obstetric populations, underscoring the importance of evaluating pregnancy outcomes in diverse women with multiple sclerosis (MS). The objective of this multicenter retrospective study was to compare pregnancy care and outcomes between Black and Hispanic (underrepresented) and White women with MS. METHODS: Demographic and clinical data were extracted from medical records of 9 US MS centers for women with MS/clinically isolated syndrome who delivered live births between 2010 and 2021. Sites identified at last 15 consecutive Black/Hispanic women and a matching number of White women. Socioeconomic factors, pregnancy, and MS care/outcomes were compared between groups (underrepresented and White and then Black and Hispanic) using Wilcoxon rank sum (U statistic and effect size r reported), χ2, t tests and logistic regressions as appropriate to data type. Multiple imputation by chained equation was used to account for missing data. RESULTS: Overall, 294 pregnancies resulting in live births were analyzed ( 81 Black, 67 Hispanic, and 146 White mothers). Relative to underrepresented women, White women lived in areas of higher median (interquartile range [IQR]) Child Opportunity Index (79 [45.8] vs 22 [45.8], U = 3,824, r = 0.56, p < 0.0001) and were more often employed (84.9% vs 75%, odds ratio [OR] 2.57, CI 1.46-4.50, p = 0.0008) and privately insured (93.8% vs 56.8%, OR 11.6, CI 5.5-24.5, p < 0.0001) and more received a 14-week ultrasound (98.6% vs 93.9%, OR 4.66, CI 0.99-21.96, p = 0.027). Mode of delivery was significantly different between the three groups (X2(10,294) = 20.38, p = 0.03); notably, Black women had the highest rates of emergency cesarean deliveries, and Hispanic women highest rates of uncomplicated vaginal deliveries. Babies born to underrepresented women had lower median (IQR) birthweights than babies born to White women (3,198 g [435.3 g] vs 3,275 g [412.5 g], U = 9,255, r = 0.12, p = 0.04) and shorter median (IQR) breastfeeding duration (4.5 [3.3] vs 6.0 [4.2] months, U = 8,184, r = 0.21, p = 0.003). While underrepresented women were younger than White women (mean [SD] 30.9 [4.8] vs 33.8 [4.0], t = 1.97, CI 1.96-3.98, p < 0.0001), their median (Q1-Q3, IQR) Expanded Disability Status Scale was higher (1.5 [1-2.5, 1.5] vs 1 [0-1.5, 1.5], U = 7,260, r = 0.29, p < 0.0001) before pregnancy. Finally, medical records were missing more key data for Black women (19.7% missing vs 8.9% missing, OR 2.54, CI 1.25-5.06, p = 0.008). DISCUSSION: In this geographically diverse multicenter cohort, underrepresented women entered pregnancy with higher disability and fewer health care resources. Pregnancy represents a pivotal window where structural factors affect maternal and fetal health and neurologic trajectories; it is a critical period to optimize care and health outcomes.

Anti-CD20 monoclonal antibody therapy in postpartum women with neurological conditions.

OBJECTIVE: Postpartum, patients with multiple sclerosis (MS) and neuromyelitis optica spectrum disorder (NMOSD) have increased risk for disease activity. Anti-CD20 IgG1 monoclonal antibodies (mAb) are increasingly used as disease-modifying therapies (DMTs). Patients may wish to both breastfeed and resume DMT postpartum. This study aimed to determine the transfer of anti-CD20 IgG1 mAbs, ocrelizumab, and rituximab (OCR/RTX), into mature breastmilk and describe maternal and infant outcomes. METHODS: Fifty-seven cis-women receiving OCR/RTX after 59 pregnancies and their infants were enrolled and followed up to 12M postpartum or 90 days post-infusion. Breastmilk was collected pre-infusion and serially up to 90 days and assayed for mAb concentration. Medical records and patients' questionnaire responses were obtained to assess neurologic, breastfeeding, and infant development outcomes. RESULTS: The median average concentration of mAb in breastmilk was low (OCR: 0.08 µg/mL, range 0.05-0.4; RTX: 0.03 µg/mL, range 0.005-0.3). Concentration peaked 1-7 days post-infusion in most (77%) and was nearly undetectable after 90 days. Median average relative infant dose was <1% (OCR: 0.1%, range 0.07-0.7; RTX: 0.04%, range 0.005-0.3). Forty-three participants continued to breastfeed post-infusion. At 8-12 months, the proportion of infants' growth between the 3rd and 97th World Health Organization percentiles did not differ for breastfed (36/40) and non-breastfed (14/16, p > 0.05) infants; neither did the proportion with normal development (breastfed: 37/41, non-breastfed: 11/13; p > 0.05). After postpartum infusion, two mothers experienced a clinical relapse. INTERPRETATION: These confirm minimal transfer of mAb into breastmilk. Anti-CD20 mAb therapy stabilizes MS activity before conception to the postpartum period, and postpartum treatments appears to be safe and well-tolerated for both mother and infant.

Severe Neuroinvasive West Nile Virus in Association With Anti-CD20 Monotherapy for Multiple Sclerosis.

OBJECTIVES: The objective of this study was to report on the development of neuroinvasive West Nile virus (WNV) infection in the context of anti-CD20 monotherapy for multiple sclerosis (MS). METHODS: This is a case series study. RESULTS: In 2021-2022, we observed 4 cases of neuroinvasive WNV infection in our patient population of 2009 patients with MS on ocrelizumab, compared with a total of 46 cases of neuroinvasive WNV infection reported in Pennsylvania and 40 in New Jersey. Odds were 258 times that of the general population (95% confidence interval 97-691), χ2 p < 0.0001). All were women aged 41-61 years with variable disease duration, level of disability, and duration of anti-CD20 therapy. All presented in summer/early fall with fever, headache, and encephalopathy consistent with meningoencephalitis. Three patients had acute cerebellitis. Two had anterior nerve root involvement progressing to quadriparesis, and 1 developed refractory nonconvulsive status epilepticus. All required intubation and experienced significant morbidity. All had CSF pleocytosis. Two patients were WNV IgM positive in both the serum and CSF, 1 patient had positive serum IgM and CSF metagenomic next-generation sequencing (mNGS), while 1 had positive CSF mNGS with negative serum and CSF antibodies. DISCUSSION: Neuroinvasive WNV infection can develop with anti-CD20 monotherapy in the absence of additional immunosuppression. WNV serologies may be negative in the setting of anti-CD20 treatment; in the appropriate clinical context, one should consider direct detection methods such as PCR or mNGS-based testing.

Pattern of thalamic nuclei atrophy in early relapse-onset multiple sclerosis.

BACKGROUND: Thalamic atrophy is prominent in multiple sclerosis; however, it is unclear which thalamic nuclei are most vulnerable, especially early in disease. INTRODUCTION: To investigate which thalamic nuclei differ between patients in early stages of relapsing-remitting multiple sclerosis (RRMS) versus healthy controls and examine the relationship between thalamic nuclei volume and T2 lesion volume. METHODS: We derived 15 thalamic subfields from high-resolution 3T magnetic resonance images in 182 patients with early RRMS (diagnosed ≤5.0 years, median 2.0 years). Independent t-tests assessed differences between patients and 35 controls across thalamic subfield volumes. Pearson correlations assessed the relationships between thalamic volumes and T2 lesion volumes. RESULTS: Patients had lower anterior and posterior nuclei volume than controls, whereas medial and ventral nuclei volumes were preserved. Higher T2 lesion volumes were disproportionately related to lower posterior subfield volumes. CONCLUSIONS: We found specific thalamic subfields were more vulnerable to early disease-related changes. We discuss potential mechanisms of differential thalamic subfield atrophy in early MS, including cortical demyelination, CSF toxicity, leptomeningeal inflammation, and iron deposition.

Dietary factors and MRI metrics in early Multiple Sclerosis.

BACKGROUND: Despite significant interest in diet by the MS community, research on this topic is limited; there are no published studies evaluating associations between diet and neuroimaging in MS. METHODS: We utilized baseline data from the RADIEMS cohort of early MS (diagnosed <5.0 years, n=180). Participants underwent brain MRIs to derive normalized total gray and thalamic volumes, T2 lesion volume, and white matter microstructural integrity of normal appearing white matter (NAWM). Participants completed food frequency questionnaires (FFQ) from which we calculated adherence scores to pre-specified dietary patterns including the Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND) diet. We evaluated intake of the following pre-specified dietary components: fruits, vegetables, legumes, nuts, whole grains, dairy, fried foods, processed meats, and fat intake. We used multivariable-adjusted linear regression to evaluate MRI metrics versus dietary measures. RESULTS: MIND diet score was associated with thalamic volume; individuals in the highest quartile of MIND diet scores had greater thalamic volumes versus those in the lowest quartile (Q4 vs. Q1: 1.03mL; 95%CI: 0.26mL, 1.79mL; p<0.01). For individual food/nutrients, higher intakes of full-fat dairy were associated with lower T2 lesion volumes (Q4 vs. Q1: -0.93mL; 95%CI: -1.51mL, -0.35ml; p<0.01). Higher intakes of marine omega-3 fatty acids were associated with greater NAWM microstructural integrity (Q4 vs. Q1: 0.40; 95%CI: 0.03, 0.76; p=0.04). Other foods/nutrients were not associated with MRI outcomes. CONCLUSIONS: In this first study focused on neuroimaging and diet in MS, we note significant associations in a cross-sectional early MS cohort. Longitudinal follow-up of imaging/clinical outcomes will provide additional insights.

Sleep disturbance and memory dysfunction in early multiple sclerosis.

OBJECTIVE: Sleep-dependent memory processing occurs in animals including humans, and disturbed sleep negatively affects memory. Sleep disturbance and memory dysfunction are common in multiple sclerosis (MS), but little is known about the contributions of sleep disturbance to memory in MS. We investigated whether subjective sleep disturbance is linked to worse memory in early MS independently of potential confounders. METHODS: Persons with early MS (n = 185; ≤5.0 years diagnosed) and demographically matched healthy controls (n = 50) completed four memory tests to derive a memory composite, and four speeded tests to derive a cognitive efficiency composite. Z-scores were calculated relative to healthy controls. Sleep disturbance was defined by the Insomnia Severity Index score ≥ 10. ANCOVAs examined differences in memory and cognitive efficiency between patients with and without sleep disturbance controlling for potential confounds (e.g., mood, fatigue, disability, T2 lesion volume, gray matter volume). Comparisons were made to healthy controls. RESULTS: Seventy-four (40%) patients reported sleep disturbance. Controlling for all covariates, patients with sleep disturbance had worse memory (z = -0.617; 95% CI: -0.886, -0.348) than patients without disturbance (z = -0.171, -0.425, 0.082, P = .003). Cognitive efficiency did not differ between groups. Relative to healthy controls, memory was worse among patients with sleep disturbance, but not among patients without sleep disturbance. INTERPRETATION: Sleep disturbance contributes to MS memory dysfunction, which may help explain differential risk for memory dysfunction in persons with MS, especially since sleep disturbance is common in MS. Potential mechanisms linking sleep disturbance and memory are discussed, as well as recommendations for further mechanistic and interventional research.

The Symbol Digit Modalities Test (SDMT) is sensitive but non-specific in MS: Lexical access speed, memory, and information processing speed independently contribute to SDMT performance.

BACKGROUND: The Symbol Digit Modalities Test (SDMT) is the most sensitive metric of neurocognitive function in multiple sclerosis (MS), and is consistently interpreted as a measure of information processing speed (IPS). OBJECTIVE: To evaluate the cognitive psychometric profile captured by the SDMT to identify whether different cognitive processes independently underlie performance. METHODS: Three samples of MS patients (total n=661; 185 research patients at MS center; 370 clinical patients at MS center; 106 persons with MS from the community) completed objective assessments of neuropsychological function across cognitive domains. Exploratory factor analysis (EFA) was used to derive latent cognitive factor scores, and operationalize cognitive domain composite scores, to understand the unique, shared and redundant contribution of different cognitive domains to SDMT performance using hierarchical multiple regression and commonality analysis. RESULTS: Across three independent samples we provide converging strong evidence that the cognitive domains of Memory, IPS and Rapid Automatized Naming (lexical access speed) jointly and uniquely contribute to SDMT performance. CONCLUSION: The SDMT measures multiple cognitive processes, which likely explains the high degree of sensitivity to cognitive change in MS. Researchers and clinicians should interpret the SDMT as a multifarious measure of general cognition rather than a specific test of IPS.

Hippocampal volume is more related to patient-reported memory than objective memory performance in early multiple sclerosis.

BACKGROUND: When persons with multiple sclerosis (MS) report memory decline but objective memory performance is normal, there is a bias toward believing objective test results. OBJECTIVE: Investigate whether subjective memory decline or objective memory performance is more related to hippocampal and hippocampal subfield volumes in early MS. METHODS: Persons with early MS (n = 185; ⩽5.0 years diagnosed) completed a subjective memory questionnaire; an objective memory composite was derived from four memory tests. Total hippocampal and subfield volumes were derived from high-resolution 3.0 T magnetic resonance images (MRIs). Partial correlations assessed links between hippocampal volumes and both subjective and objective memory, controlling for age, sex, mood, and pre-morbid intelligence quotient (IQ). RESULTS: Lower total hippocampal and CA1 volumes were related to worse subjective memory but not objective memory (controlling for multiple comparisons). Correlations between subjective memory and both CA1 and subiculum were significantly stronger than were correlations between objective memory and these subfields. Patients in the worst tertile of subjective memory complaints (but not objective memory) had lower hippocampal volumes than 35 demographically similar healthy controls. CONCLUSION: Patient-report is inherently a longitudinal assessment of within-person memory change in everyday life, which may be more sensitive to subtle disease-related changes than cross-sectional objective tests. Findings align with the aging literature.

Depression and cognitive function in early multiple sclerosis: Multitasking is more sensitive than traditional assessments.

BACKGROUND: Persons with multiple sclerosis (MS) and depression symptoms report real-world cognitive difficulties that may be missed by laboratory cognitive tests. OBJECTIVE: To examine the relationship of depressive symptoms to cognitive monotasking versus multitasking in early MS. METHOD: Persons with early MS (n = 185; ⩽5 years diagnosed) reported mood, completed monotasking and multitasking cognitive tests, and received high-resolution 3.0 T magnetic resonance imaging (MRI). Partial correlations analyzed associations between mood and cognition, controlling for age, sex, estimated premorbid IQ, T2 lesion volume, and normalized gray matter volume. RESULTS: Depression symptoms were more related to worse cognitive multitasking (-0.353, p < 0.001) than monotasking (r = -0.189, p = 0.011). There was a significant albeit weaker link to cognitive efficiency composite score (r = -0.281, p < 0.001), but not composite memory (r = -0.036, p > 0.50). Findings were replicated with a second depression measure. Multitasking was worse in patients with at least mild depression than both patients with no/minimal depression and healthy controls. Multitasking was not related to mood in healthy controls. CONCLUSIONS: Depression symptoms are linked to cognitive multitasking in early MS; standard monotasking cognitive assessments appear less sensitive to depression-related cognition. Further investigation should determine directionality and mechanisms of this relationship, with the goal of enhancing treatment for cognitive dysfunction and depression in MS.

Training in Neurology: Diagnostic Accuracy Among Neurology Residents: The "Close the Loop" Project.

OBJECTIVE: To describe cases presented by junior neurology residents and to evaluate resident diagnostic patterns to help address individual and systemic educational needs. METHODS: For 6 academic years, details of all morning report cases assessed and presented by junior neurology residents were logged, including the resident's independent initial diagnostic impression. Cases were later revisited at subsequent morning reports to "close the loop" on a final diagnosis. We conducted retrospective review to quantify case demographics and to determine resident diagnostic accuracy based on prespecified localization pathways. RESULTS: Demographic analysis included 1,472 cases; of these, 1,301 qualified for accuracy analysis due to diagnostic uncertainty at time of morning report. Non-neurologic etiologies represented 26.0% of cases. CNS etiologies were the majority (86.0%) of neurologic cases. The most frequent diagnoses were ischemic stroke and seizure. Overall resident diagnostic accuracy was 64.0%. Accuracy was similar between central and peripheral etiologies. Of 1,301 cases, 15.3% were overcalled as neurologic, while neurologic disease was rarely mistaken as non-neurologic (5.1%). Most diagnostic errors (49.1%) occurred when determining whether a case was neurologic. Where in the localization pathway errors occurred varied between etiologies. CONCLUSION: Overall diagnostic accuracy for neurology junior residents in our cohort was similar to prior work conducted in smaller samples. Analysis of errors, particularly at the critical "neurologic or non-neurologic" decision point, warrants further investigation. Close the loop methodology is simple to employ and can guide educational and quality initiatives to improve neurology resident clinical acumen.

TAPAS: A Thresholding Approach for Probability Map Automatic Segmentation in Multiple Sclerosis.

Total brain white matter lesion (WML) volume is the most widely established magnetic resonance imaging (MRI) outcome measure in studies of multiple sclerosis (MS). To estimate WML volume, there are a number of automatic segmentation methods available, yet manual delineation remains the gold standard approach. Automatic approaches often yield a probability map to which a threshold is applied to create lesion segmentation masks. Unfortunately, few approaches systematically determine the threshold employed; many methods use a manually selected threshold, thus introducing human error and bias into the automated procedure. In this study, we propose and validate an automatic thresholding algorithm, Thresholding Approach for Probability Map Automatic Segmentation in Multiple Sclerosis (TAPAS), to obtain subject-specific threshold estimates for probability map automatic segmentation of T2-weighted (T2) hyperintense WMLs. Using multimodal MRI, the proposed method applies an automatic segmentation algorithm to obtain probability maps. We obtain the true subject-specific threshold that maximizes the Sørensen-Dice similarity coefficient (DSC). Then the subject-specific thresholds are modeled on a naive estimate of volume using a generalized additive model. Applying this model, we predict a subject-specific threshold in data not used for training. We ran a Monte Carlo-resampled split-sample cross-validation (100 validation sets) using two data sets: the first obtained from the Johns Hopkins Hospital (JHH) on a Philips 3 Tesla (3T) scanner (n = 94) and a second collected at the Brigham and Women's Hospital (BWH) using a Siemens 3T scanner (n = 40). By means of the proposed automated technique, in the JHH data we found an average reduction in subject-level absolute error of 0.1 mL per one mL increase in manual volume. Using Bland-Altman analysis, we found that volumetric bias associated with group-level thresholding was mitigated when applying TAPAS. The BWH data showed similar absolute error estimates using group-level thresholding or TAPAS likely since Bland-Altman analyses indicated no systematic biases associated with group or TAPAS volume estimates. The current study presents the first validated fully automated method for subject-specific threshold prediction to segment brain lesions.

COVID-19 and MS disease-modifying therapies.

OBJECTIVE: To address concerns regarding the effect of MS disease-modifying therapies (DMTs) on the expression of coronavirus 2019 (COVID-19). METHODS: Review of the current state of knowledge regarding the viral etiology of COVID-19, mechanisms of injury by SARS-CoV-2 infection, and the effect of individual DMTs on the risk of infection and COVID-19 disease expression. RESULTS: Although data are limited, MS DMTs do not obviously increase the risk of acquiring symptomatic SARS-CoV-2 infection. The severe morbidity and mortality of SARS-CoV-2 appear to be largely the consequence of an overly robust immune response rather than the consequence of unchecked viral replication. The effects of specific MS DMTs on the immune response that may increase the risk of impaired viral clearance and their potential counterbalancing beneficial effects on the development of COVID-19-associated acute respiratory distress syndrome are reviewed. CONCLUSION: Although there is currently insufficient real-world experience to definitively answer the question of the effect of a specific MS DMT on COVID-19, registries presently in nascent form should provide these answers. This review provides an approach to addressing these concerns while the data are being accumulated. Early insights suggest that the risk of infection and associated morbidity of COVID-19 in this population is little different than that of the population at large.

Detection of subtle gait disturbance and future fall risk in early multiple sclerosis.

OBJECTIVE: To test the hypothesis that higher-challenge gait and balance tasks are more sensitive than traditional metrics to subtle patient-reported gait dysfunction and future fall risk in early multiple sclerosis (MS). METHODS: Persons with early MS (n = 185; ≤5 years diagnosed) reported gait function (MS Walking Scale) and underwent traditional disability metrics (Expanded Disability Status Scale [EDSS], Timed 25 Foot Walk). Patients and healthy controls (n = 50) completed clinically feasible challenge tasks of gait endurance (2-Minute Walk Test), standing balance (NIH Toolbox), and dynamic balance (balance boards; tandem walk on 2 ten-foot boards of different widths, 4.5 and 1.5 in). MRI assessed global and regional brain volumes, total T2 lesion volume (T2LV), infratentorial T2LVs and counts, and cervical cord lesion counts. Falls, near falls, and fall-related injuries were assessed after 1 year. We examined links between all tasks and patient-reported gait, MRI markers, and fall data. RESULTS: Patients performed worse on higher challenge balance, but not gait, tasks compared with healthy controls. Worse patient-reported gait disturbance was associated with worse performance on all tasks, but only dynamic balance was sensitive to mild patient-reported gait difficulty. Balance tasks were more correlated with MRI metrics than were walking tasks or EDSS score. Thirty percent of patients reported either a fall or near fall after 1 year, with poor dynamic balance as the only task independently predicting falls. CONCLUSIONS: Balance plays a leading role in gait dysfunction early in MS. Clinically feasible higher-challenge balance tasks were most sensitive to patient-reported gait, MRI disease markers, and risk of future falls, highlighting potential to advance functional outcomes in clinical practice and trials.

Dissociable cognitive patterns related to depression and anxiety in multiple sclerosis.

BACKGROUND: Individuals with multiple sclerosis (MS) frequently present with depression and anxiety, as well as cognitive impairment, challenging clinicians to disentangle interrelationships among these symptoms. OBJECTIVE: To identify cognitive functions associated with anxiety and depression in MS. METHODS: Mood and cognition were measured in 185 recently diagnosed patients (Reserve Against Disability in Early Multiple Sclerosis (RADIEMS) cohort), and an independent validation sample (MEM CONNECT cohort, n = 70). Partial correlations evaluated relationships of cognition to anxiety and depression controlling for age, sex, education, and premorbid verbal intelligence. RESULTS: In RADIEMS cohort, lower anxiety was associated with better nonverbal memory (rp = -0.220, p = 0.003) and lower depression to better attention/processing speed (rp = -0.241, p = 0.001). Consistently, in MEM CONNECT cohort, lower anxiety was associated with better nonverbal memory (rp = -0.271, p = 0.028) and lower depression to better attention/processing speed (rp = -0.367, p = 0.002). Relationships were unchanged after controlling for T2 lesion volume and fatigue. CONCLUSION: Consistent mood-cognition relationships were identified in two independent cohorts of MS patients, suggesting that cognitive correlates of anxiety and depression are separable. This dissociation may support more precise models to inform treatment development. Treatment of mood symptoms may mitigate effects on cognition and/or treatment of cognition may mitigate effects on mood.

Psychological resilience is linked to motor strength and gait endurance in early multiple sclerosis.

BACKGROUND: Psychologically resilient persons persist despite obstacles and bounce back after adversity, leading to better outcomes in non-neurologic populations. It is unknown whether psychological resilience relates to objective functional outcomes in multiple sclerosis (MS). OBJECTIVE: To determine whether psychological resilience explains differential objective cognitive and motor functioning in persons with early MS. METHODS: Psychological resilience was assessed in 185 patients with early MS and 50 matched healthy controls with the Connors-Davidson Resilience Scale (CDRS-10). Subjects completed the MS Functional Composite (MSFC) and a comprehensive neurobehavioral evaluation. Correlations assessed links between CDRS-10 and MSFC, motor indices (Total, Fine Motor, Gross Motor), and cognitive indices (Total, Cognitive Efficiency, Memory). RESULTS: Higher CDRS-10 among patients was linked to better MSFC and motor outcomes (but not cognition), with the most robust relationships for gross motor function (grip strength, gait endurance). Findings were independent of mood and fatigue. CDRS-10 was unrelated to MS disease burden. CDRS-10 was also specifically linked to motor outcomes in healthy controls. CONCLUSION: Functional outcomes vary across persons with MS, even when disease burden and neurologic disability are low. These findings identify high psychological resilience as a non-disease-specific contributor to motor strength and endurance, which may explain differential outcomes across patients.

Word-finding difficulty is a prevalent disease-related deficit in early multiple sclerosis.

BACKGROUND: Persons with multiple sclerosis (MS) commonly report word-finding difficulty clinically, yet this language deficit remains underexplored. OBJECTIVE: To investigate the prevalence and nature of word-finding difficulty in persons with early MS on three levels: patient report, cognitive substrates, and neuroimaging. METHODS: Two samples of early MS patients (n = 185 and n = 55; ⩽5 years diagnosed) and healthy controls (n = 50) reported frequency/severity of cognitive deficits and underwent objective assessment with tasks of rapid automatized naming (RAN), measuring lexical access speed, memory, word generation, and cognitive efficiency. High-resolution brain magnetic resonance imaging (MRI) derived measurements of regional cortical thickness, global and deep gray matter volume, and T2 lesion volume. Relationships among patient-reported word-finding difficulty, cognitive performance, and neural correlates were examined. RESULTS: Word-finding difficulty was the most common cognitive complaint of MS patients and the only complaint reported more by patients than healthy controls. Only RAN performance discriminated MS patients with subjective word-finding deficits from those without subjective complaints and from healthy controls. Thinner left parietal cortical gray matter independently predicted impaired RAN performance, driven primarily by the left precuneus. CONCLUSION: Three levels of evidence (patient-report, objective behavior, regional gray matter) support word-finding difficulty as a prevalent, measurable, disease-related deficit in early MS linked to left parietal cortical thinning.

Beyond rehabilitation: A prevention model of reserve and brain maintenance in multiple sclerosis.

Persons with multiple sclerosis (MS) experience cognitive and physical decline despite more effective disease-modifying therapies (DMTs), and symptomatic treatments currently have limited efficacy. The best treatment of MS disability may, therefore, be prevention of decline. Here, we present a working model of reserve and brain maintenance, with a focus on modifiable risk and protective factors. At disease onset, patients have varying degrees of reserve, broadly conceptualized as the dynamic availability of cerebral resources to support functional capacity. A clinical focus on prevention aims to minimize factors that deplete reserve (e.g. disease burden, comorbidities) and maximize factors that preserve reserve (e.g. DMTs, cardiovascular health). We review evidence for cardiovascular health, diet, and sleep as three potentially important modifiable factors that may modulate cerebral reserve generally, but also in disease-specific ways. We frame the brain as a limited capacity system in which inefficient usage of available cerebral capacity (reserve) leads to or exacerbates functional deficits, and we provide examples of factors that may lead to such inefficiency (e.g. poor mood, obesity, cognitive-motor dual-tasking). Finally, we discuss the challenges and responsibilities of MS neurologists and patients in pursuing comprehensive brain maintenance as a preventive approach.

Fumarates target the metabolic-epigenetic interplay of brain-homing T cells in multiple sclerosis.

Cell-permeable formulations of metabolites, such as fumaric acid esters, have been used as highly effective immunomodulators in patients with multiple sclerosis and yet their mechanism of action remains elusive. Since fumaric acid esters are metabolites, and cell metabolism is highly intertwined with the epigenetic regulation of gene expression, we investigated whether this metabolic-epigenetic interplay could be leveraged for therapeutic purposes. To this end we recruited 47 treatment-naïve and 35 fumaric acid ester-treated patients with multiple sclerosis, as well as 16 glatiramer acetate-treated patients as a non-metabolite treatment control. Here we identify a significant immunomodulatory effect of fumaric acid esters on the expression of the brain-homing chemokine receptor CCR6 in CD4 and CD8 T cells of patients with multiple sclerosis, which include T helper-17 and T cytotoxic-17 cells. We report differences in DNA methylation of CD4 T cells isolated from untreated and treated patients with multiple sclerosis, using the Illumina EPIC 850K BeadChip. We first demonstrate that Krebs cycle intermediates, such as fumaric acid esters, have a significantly higher impact on epigenome-wide DNA methylation changes in CD4 T cells compared to amino-acid polymers such as glatiramer acetate. We then define a fumaric acid ester treatment-specific hypermethylation effect on microRNA MIR-21, which is critical for the differentiation of T helper-17 cells. This hypermethylation effect was attributed to the subpopulation of T helper-17 cells using a decomposition analysis and was further validated in an independent prospective cohort of seven patients before and after treatment with fumaric acid esters. In vitro treatment of CD4 and CD8 T cells with fumaric acid esters supported a direct and dose-dependent effect on DNA methylation at the MIR-21 promoter. Finally, the upregulation of miR-21 transcripts and CCR6 expression was inhibited if CD4 or CD8 T cells stimulated under T helper-17 or T cytotoxic-17 polarizing conditions were treated with fumaric acid esters in vitro. These data collectively define a direct link between fumaric acid ester treatment and hypermethylation of the MIR-21 locus in both CD4 and CD8 T cells and suggest that the immunomodulatory effect of fumaric acid esters in multiple sclerosis is at least in part due to the epigenetic regulation of the brain-homing CCR6+ CD4 and CD8 T cells.

Disease-modifying therapies alter gut microbial composition in MS.

Objective: To determine the effects of the disease-modifying therapies, glatiramer acetate (GA) and dimethyl fumarate (DMF), on the gut microbiota in patients with MS. Methods: Participants with relapsing MS who were either treatment-naive or treated with GA or DMF were recruited. Peripheral blood mononuclear cells were immunophenotyped. Bacterial DNA was extracted from stool, and amplicons targeting the V4 region of the bacterial/archaeal 16S rRNA gene were sequenced (Illumina MiSeq). Raw reads were clustered into Operational Taxonomic Units using the GreenGenes database. Differential abundance analysis was performed using linear discriminant analysis effect size. Phylogenetic investigation of communities by reconstruction of unobserved states was used to investigate changes to functional pathways resulting from differential taxon abundance. Results: One hundred sixty-eight participants were included (treatment-naive n = 75, DMF n = 33, and GA n = 60). Disease-modifying therapies were associated with changes in the fecal microbiota composition. Both therapies were associated with decreased relative abundance of the Lachnospiraceae and Veillonellaceae families. In addition, DMF was associated with decreased relative abundance of the phyla Firmicutes and Fusobacteria and the order Clostridiales and an increase in the phylum Bacteroidetes. Despite the different changes in bacterial taxa, there was an overlap between functional pathways affected by both therapies. Interpretation: Administration of GA or DMF is associated with differences in gut microbial composition in patients with MS. Because those changes affect critical metabolic pathways, we hypothesize that our findings may highlight mechanisms of pathophysiology and potential therapeutic intervention requiring further investigation.