Phenotype and prognosis in African-Americans with multiple sclerosis: a retrospective chart review

Efficacy and tolerability of dimethyl fumarate in White-, African- and Hispanic- Americans with multiple sclerosis

BACKGROUND

Dimethyl fumarate (DMF) was approved by the US Food and Drug Administration (FDA) for treatment of relapsing-remitting multiple sclerosis (RRMS) based on two phase III randomized clinical trials (RCTs). There were not enough non-White patients enrolled in these RCTs to allow for subgroup analysis based on race. Efficacy and tolerability of DMF therapy across various racial groups is unknown.

METHODS

Retrospective chart review was performed on all patients with RRMS who were started on DMF in two tertiary multiple sclerosis (MS) clinics. Efficacy and tolerability of DMF was compared across three self-identified racial groups: White-American (WA), African-American (AA) and Hispanic-American (HA).

RESULTS

A total of 390 RRMS patients were included in the study: 261 (66.9%) WA, 69 (17.7%) AA and 52 (13.3%) HA. When comparing 'pre-DMF' (1 year) and 'on DMF' (mean follow up of 14 months) periods, statistically significant reduction in rates of annualized relapses (WA from 0.44 to 0.19, AA from 0.39 to 0.15, and HA from 0.39 to 0.14; no differences between groups), new T2 lesions (WA from 45% to 23%, AA from 39% to 23%, HA from 52% to 26%; no difference between groups), and Gd+ lesions (WA from 25% to 13%, AA from 24% to 7%, HA from 23% to 12%; no difference between groups) were seen. DMF was relatively well tolerated across all groups, with an overall discontinuation rate of 20% (no difference between the three groups).

CONCLUSION

Efficacy of DMF in our clinic population did not differ across three major ethnic groups, WA, AA and HA, and was comparable with results observed in the pivotal studies. These 'real-life' data suggest that race is not a factor that needs to be taken into account when initiating DMF.

Role of socioeconomic position in multiple sclerosis etiology

Multiple sclerosis (MS) is a debilitating autoimmune disease with a prominent inflammatory component. There have been strides identifying genetic and environmental MS risk factors, though much of the disease risk remains unknown. Recent large observational studies suggest adverse socioeconomic position increases the risk for MS, however the mediating biological processes are not understood. We hypothesize a prominent role for stress response, both the autonomic nervous system and the hypothalamic–pituitary–adrenal axis, which become maladaptive under frequent or chronic stimulation resulting in a proinflammatory phenotype. Thus, adverse SEP and chronic stress may predispose individuals for MS.

Preferential Recruitment of Neutrophils into the Cerebellum and Brainstem Contributes to the Atypical Experimental Autoimmune Encephalomyelitis Phenotype

The JAK/STAT pathway is critical for development, regulation, and termination of immune responses, and dysregulation of the JAK/STAT pathway, that is, hyperactivation, has pathological implications in autoimmune and neuroinflammatory diseases. Suppressor of cytokine signaling 3 (SOCS3) regulates STAT3 activation in response to cytokines that play important roles in the pathogenesis of neuroinflammatory diseases, including IL-6 and IL-23. We previously demonstrated that myeloid lineage-specific deletion of SOCS3 resulted in a severe, nonresolving atypical form of experimental autoimmune encephalomyelitis (EAE), characterized by lesions, inflammatory infiltrates, elevated STAT activation, and elevated cytokine and chemokine expression in the cerebellum. Clinically, these mice exhibit ataxia and tremors. In this study, we provide a detailed analysis of this model, demonstrating that the atypical EAE observed in LysMCre-SOCS3(fl/fl) mice is characterized by extensive neutrophil infiltration into the cerebellum and brainstem, increased inducible NO synthase levels in the cerebellum and brainstem, and prominent axonal damage. Importantly, infiltrating SOCS3-deficient neutrophils produce high levels of CXCL2, CCL2, CXCL10, NO, TNF-α, and IL-1β. Kinetic studies demonstrate that neutrophil infiltration into the cerebellum and brainstem of LysMCre-SOCS3(fl/fl) mice closely correlates with atypical EAE clinical symptoms. Ab-mediated depletion of neutrophils converts the atypical phenotype to the classical EAE phenotype and, in some cases, a mixed atypical/classical phenotype. Blocking CXCR2 signaling ameliorates atypical EAE development by reducing neutrophil infiltration into the cerebellum/brainstem. Thus, neutrophils lacking SOCS3 display elevated STAT3 activation and expression of proinflammatory mediators and play a critical role in the development of atypical EAE.

Differential diagnosis of Mendelian and mitochondrial disorders in patients with suspected multiple sclerosis

Several single gene disorders share clinical and radiologic characteristics with multiple sclerosis and have the potential to be overlooked in the differential diagnostic evaluation of both adult and paediatric patients with multiple sclerosis. This group includes lysosomal storage disorders, various mitochondrial diseases, other neurometabolic disorders, and several other miscellaneous disorders. Recognition of a single-gene disorder as causal for a patient's 'multiple sclerosis-like' phenotype is critically important for accurate direction of patient management, and evokes broader genetic counselling implications for affected families. Here we review single gene disorders that have the potential to mimic multiple sclerosis, provide an overview of clinical and investigational characteristics of each disorder, and present guidelines for when clinicians should suspect an underlying heritable disorder that requires diagnostic confirmation in a patient with a definite or probable diagnosis of multiple sclerosis.

Retinal damage and vision loss in African American multiple sclerosis patients

OBJECTIVE

To determine whether African American (AA) multiple sclerosis (MS) patients exhibit more retinal damage and visual impairment compared to Caucasian American (CA) MS patients.

METHODS

A total of 687 MS patients (81 AAs) and 110 healthy control (HC) subjects (14 AAs) were recruited at 3 academic hospitals between 2008 and 2012. Using mixed effects regression models, we compared high- and low-contrast visual acuity (HCVA and LCVA) and high-definition spectral domain optical coherence tomography measures of retinal architecture between MS patients of self-identified AA and CA ancestry.

RESULTS

In HCs, baseline peripapillary retinal nerve fiber layer (RNFL) thickness was 6.1µm greater in AAs (p = 0.047), whereas ganglion cell/inner plexiform layer (GCIP) thickness did not differ by race. In MS patients, baseline RNFL did not differ by race, and GCIP was 3.98µm thinner in AAs (p = 0.004). AAs had faster RNFL and GCIP thinning rates compared to CAs (p = 0.004 and p = 0.046, respectively). AA MS patients had lower baseline HCVA (p = 0.02) and worse LCVA per year of disease duration (p = 0.039). Among patients with an acute optic neuritis (AON) history, AAs had greater loss of HCVA than CA patients (p = 0.012).

INTERPRETATION

This multicenter investigation provides objective evidence that AA MS patients exhibit accelerated retinal damage compared to CA MS patients. Self-identified AA ancestry is associated with worse MS-related visual disability, particularly in the context of an AON history, suggesting a more aggressive inflammatory disease course among AA MS patients or a subpopulation therein.

Genomewide admixture study in Mexican Mestizos with multiple sclerosis

BACKGROUND

Multiple sclerosis (MS) is a complex immune-mediated disease. It has been suggested that genetic factors could explain differences in the prevalence among ethnic groups. To know whether genetic ancestry is a potential risk factor for MS in Mexican patients and to identify candidate genes for the susceptibility to the disease we conducted an initial trial of genome-wide analysis.

METHODS

29 patients with diagnosis of definitive MS and 132 unrelated healthy controls were genotyped using the Affymetrix human 6.0 array. After QC procedures, ancestry determination and a preliminary case-control association study were performed.

RESULTS

We identified significant differences in the European ancestry proportion between MS cases and controls (33.1 vs. 25.56, respectively; p=0.0045). Imputation analysis in the MHC region on chromosome 6 showed a signal with a significant level (p<0.00005) on the HLA-DRB region. Additionally, a preliminary association analysis highlighted the ASF1B as novel candidate gene participating in MS.

CONCLUSION

Our data suggest that European ancestry is a risk factor to develop MS in Mexican Mestizo population. Conversely, indigenous ancestry of Asian origin seems to confer protection. Further studies with more MS cases are needed to confirm these findings.

Treatment Optimization in MS: Canadian MS Working Group Updated Recommendations

The Canadian Multiple Sclerosis Working Group (CMSWG) developed practical recommendations in 2004 to assist clinicians in optimizing the use of disease-modifying therapies (DMT) in patients with relapsing multiple sclerosis. The CMSWG convened to review how disease activity is assessed, propose a more current approach for assessing suboptimal response, and to suggest a scheme for switching or escalating treatment. Practical criteria for relapses, Expanded Disability Status Scale (EDSS) progression and MRI were developed to classify the clinical level of concern as Low, Medium and High. The group concluded that a change in treatment may be considered in any RRMS patient if there is a high level of concern in any one domain (relapses, progression or MRI), a medium level of concern in any two domains, or a low level of concern in all three domains. These recommendations for assessing treatment response should assist clinicians in making more rational choices in their management of relapsing MS patients.

Cross-reactivity between human cytomegalovirus peptide 981-1003 and myelin oligodendroglia glycoprotein peptide 35-55 in experimental autoimmune encephalomyelitis in Lewis rats

Multiple sclerosis (MS) has been documented to have various clinical and pathological presentations. However the underlying mechanisms remain unknown. Viral infections may play a certain role in the etiopathogenesis of MS. This study was designed to explore whether different phospholipid peptides and viral mimic peptides induce antigen specific lesion in experimental autoimmune encephalomyelitis (EAE), an MS animal model. In the present study, Lewis rats immunized with myelin basic protein (MBP) 82-99 or MBP68-86 exhibited clinical signs of EAE and inflammatory infiltrates throughout CNS. Immunization with myelin oligodendroglia glycoprotein (MOG) 35-55 also induced inflammatory infiltrates in spinal cords. Although cytomegalovirus (CMV) 981-1003 failed to induce clinical signs of EAE and inflammatory infiltrates, immunological examination revealed that CMV981-1003 cross-reacted with serum from rats immunized with MOG35-55, and vice versa. Further, MOG35-55 triggered CMV981-1003 specific lymphocytes recruitment in spleen. Together these, this study provides certain evidences for various pathological manifestations of EAE and the linkage of viral mimic peptides with phospholipid peptides. Molecular mimicry may be an explanation the pathogenesis of MS.

Quantitative MRI analysis in children with multiple sclerosis: a multicenter feasibility pilot study

BACKGROUND

Pediatric multiple sclerosis (MS) is a rare disorder with significant consequences. Quantitative MRI measurements may provide significant insights, however multicenter collaborative studies are needed given the small numbers of subjects. The goal of this study is to demonstrate feasibility and evaluate lesion volume (LV) characteristics in a multicenter cohort of children with MS.

METHODS

A common MRI-scanning guideline was implemented at six member sites of the U.S. Network of Pediatric MS Centers of Excellence. We included in this study the first ten scans performed at each site on patients meeting the following inclusion criteria: pediatric RRMS within 3 years of disease onset, examination within 1 month of MRI and no steroids 1 month prior to MRI. We quantified T2 number, T2-LV and individual lesion size in a total of 53 MRIs passing quality control procedures and assessed gadolinium-enhancing lesion number and LV in 55 scans. We studied MRI measures according to demographic features including age, race, ethnicity and disability scores, controlling for disease duration and treatment duration using negative binomial regression and linear regression.

RESULTS

The mean number of T2 lesions was 24.30 ± 19.68 (range:1-113) and mean gadolinium-enhancing lesion count was 1.85 ± 5.84, (range:0-32). Individual lesion size ranged from 14.31 to 55750.60 mm3. Non-white subjects had higher T2-LV (unadjusted pT2-LV = 0.028; adjusted pT2-LV = 0.044), and maximal individual T2-LV (unadjusted pMax = 0.007; adjusted pMax = 0.011) than white patients. We also found a trend toward larger mean lesion size in males than females (p = 0.07).

CONCLUSION

Assessment of MRI lesion LV characteristics is feasible in a multicenter cohort of children with MS.

Pre-existing central nervous system lesions negate cytokine requirements for regional experimental autoimmune encephalomyelitis development

In region-specific forms of experimental autoimmune encephalomyelitis (EAE), lesion initiation is regulated by T-cell-produced interferon-γ (IFN-γ) resulting in spinal cord disease in the presence of IFN-γ and cerebellar disease in the absence of IFN-γ. Although this role for IFN-γ in regional disease initiation is well defined, little is known about the consequences of previous tissue inflammation on subsequent regional disease, information vital to the development of therapeutics in established disease states. This study addressed the hypothesis that previous establishment of regional EAE would determine subsequent tissue localization of new T-cell invasion and associated symptoms regardless of the presence or absence of IFN-γ production. Serial transfer of optimal or suboptimal doses of encephalitogenic IFN-γ-sufficient or -deficient T-cell lines was used to examine the development of new clinical responses associated with the spinal cord and cerebellum at various times after EAE initiation. Previous inflammation within either cerebellum or spinal cord allowed subsequent T-cell driven inflammation within that tissue regardless of IFN-γ presence. Further, T-cell IFN-γ production after initial lesion formation exacerbated disease within the cerebellum, suggesting that IFN-γ plays different roles at different stages of cerebellar disease. For the spinal cord, IFN-γ-deficient cells (that are ordinarily cerebellum disease initiators) were capable of driving new spinal-cord-associated clinical symptoms more than 60 days after the initial acute EAE resolution. These data suggest that previous inflammation modulates the molecular requirements for new neuroinflammation development.

African ancestry is a predictor factor to secondary progression in clinical course of multiple sclerosis

Background. Studies on the clinical course of multiple sclerosis have indicated that certain initial clinical factors are predictive of disease progression. Regions with a low prevalence for disease, which have environmental and genetic factors that differ from areas of high prevalence, lack studies on the progressive course and disabling characteristics of the disease. Objective. To analyse the long-term evolution to the progressive phase of the relapsing-remitting multiple sclerosis and its prognosis factors in mixed population. Methods. We performed a survival study and logistic regression to examine the influence of demographic and initial clinical factors on disease progression. Among 553 relapsing-remitting patients assisted at a Brazilian reference centre for multiple sclerosis, we reviewed the medical records of 150 patients who had a disease for ten or more years. Results. African ancestry was a factor that conferred more risk for secondary progression followed by age at the onset of the disease and the number of relapses in the year after diagnosis. A greater understanding of the influence of ancestry on prognosis serves to stimulate genetics and pharmacogenomics research and may clarify the poorly understood neurodegenerative progression of MS.

MRI correlates of disability in African-Americans with multiple sclerosis

OBJECTIVES

Multiple sclerosis (MS) in African-Americans (AAs) is characterized by more rapid disease progression and poorer response to treatment than in Caucasian-Americans (CAs). MRI provides useful and non-invasive tools to investigate the pathological substrate of clinical progression. The aim of our study was to compare MRI measures of brain damage between AAs and CAs with MS.

METHODS

Retrospective analysis of 97 AAs and 97 CAs with MS matched for age, gender, disease duration and age at MRI examination.

RESULTS

AA patients had significantly greater T2- (p = 0.001) and T1-weighted (p = 0.0003) lesion volumes compared to CA patients. In contrast, measurements of global and regional brain volume did not significantly differ between the two ethnic groups (p>0.1).

CONCLUSIONS

By studying a quite large sample of well demographically and clinically matched CA and AA patients with a homogeneous MRI protocol we showed that higher lesion accumulation, rather than pronounced brain volume decrease might explain the early progress to ambulatory assistance of AAs with MS.

Signal transducer and activator of transcription-3/suppressor of cytokine signaling-3 (STAT3/SOCS3) axis in myeloid cells regulates neuroinflammation

Suppressor of cytokine signaling (SOCS) proteins are feedback inhibitors of the JAK/STAT pathway. SOCS3 has a crucial role in inhibiting STAT3 activation, cytokine signaling, and inflammatory gene expression in macrophages/microglia. To determine the role of SOCS3 in myeloid cells in neuroinflammation, mice with conditional SOCS3 deletion in myeloid cells (LysMCre-SOCS3(fl/fl)) were tested for experimental autoimmune encephalomyelitis (EAE). The myeloid-specific SOCS3-deficient mice are vulnerable to myelin oligodendrocyte glycoprotein (MOG)-induced EAE, with a severe, nonresolving atypical form of disease. In vivo, enhanced infiltration of inflammatory cells and demyelination is prominent in the cerebellum of myeloid-specific SOCS3-deficient mice, as is enhanced STAT3 signaling and expression of inflammatory cytokines/chemokines and an immune response dominated by Th1 and Th17 cells. In vitro, SOCS3-deficient macrophages exhibit heightened STAT3 activation and are polarized toward the classical M1 phenotype. SOCS3-deficient M1 macrophages provide the microenvironment to polarize Th1 and Th17 cells and induce neuronal death. Furthermore, adoptive transfer of M2 macrophages into myeloid SOCS3-deficient mice leads to delayed onset and reduced severity of atypical EAE by decreasing STAT3 activation, Th1/Th17 cells, and proinflammatory mediators in the cerebellum. These findings indicate that myeloid cell SOCS3 provides protection from EAE through deactivation of neuroinflammatory responses.

IFN-gamma signaling in the central nervous system controls the course of experimental autoimmune encephalomyelitis independently of the localization and composition of inflammatory foci

Background

Murine experimental autoimmune encephalomyelitis (EAE), a model for multiple sclerosis, presents typically as ascending paralysis. However, in mice in which interferon-gamma (IFNγ) signaling is disrupted by genetic deletion, limb paralysis is accompanied by atypical deficits, including head tilt, postural imbalance, and circling, consistent with cerebellar/vestibular dysfunction. This was previously attributed to intense cerebellar and brainstem infiltration by peripheral immune cells and formation of neutrophil-rich foci within the CNS. However, the exact mechanism by which IFNγ signaling prohibits the development of vestibular deficits, and whether the distribution and composition of inflammatory foci within the CNS affects the course of atypical EAE remains elusive.

Methods

We induced EAE in IFNγ-/- mice and bone marrow chimeric mice in which IFNγR is not expressed in the CNS but is intact in the periphery (IFNγR^CNSKO) and vice versa (IFNγR^periKO). Blood-brain barrier permeability was determined by Evans blue intravenous administration at disease onset. Populations of immune cell subsets in the periphery and the CNS were quantified by flow cytometry. CNS tissues isolated at various time points after EAE induction, were analyzed by immunohistochemistry for composition of inflammatory foci and patterns of axonal degeneration.

Results

Incidence and severity of atypical EAE were more pronounced in IFNγR^CNSKO as compared to IFNγR^periKO mice. Contrary to what we anticipated, cerebella/brainstems of IFNγR^CNSKO mice were only minimally infiltrated, while the same areas of IFNγR^periKO mice were extensively populated by peripheral immune cells. Furthermore, the CNS of IFNγR^periKO mice was characterized by persistent neutrophil-rich foci as compared to IFNγR^CNSKO. Immunohistochemical analysis of the CNS of IFNγ-/- and IFNγR chimeric mice revealed that IFNγ protective actions are exerted through microglial STAT1.

Conclusions

Alterations in distribution and composition of CNS inflammatory foci are not sufficient for the onset of atypical EAE. IFNγ dictates the course of neuroinflammatory disorders mainly through actions exerted within the CNS. This study provides strong evidence that link microglial STAT1 inactivation to vestibular dysfunction.

Demographic, genetic, and environmental factors that modify disease course

As with susceptibility to disease, it is likely that multiple factors interact to influence the phenotype of multiple sclerosis and long-term disease outcomes. Such factors may include genetic factors, socioeconomic status, comorbid diseases, and health behaviors, as well as environmental exposures. An improved understanding of the influence of these factors on disease course may reap several benefits, such as improved prognostication, allowing us to tailor disease management with respect to intensity of disease-modifying therapies and changes in specific health behaviors, in the broad context of coexisting health issues. Such information can facilitate appropriately adjusted comparisons within and between populations. Elucidation of these factors will require careful study of well-characterized populations in which the roles of multiple factors are considered simultaneously.

Natural history of multiple sclerosis: early prognostic factors

Multiple sclerosis is a heterogeneous disease, and predicting its course is difficult at the individual level. In this article, clinical, demographic, and additional features that are associated with the risk of relapses and of intermediate-term disability are reviewed.

Genetics for understanding and predicting clinical progression in multiple sclerosis

INTRODUCTION

Multiple sclerosis (MS) is a dys-immune disease of the central nervous system with highly variable and unpredictable long-term outcome.

STATE OF THE ART

In the early 1970s association between HLA alleles and MS was established. Very recently, the power of Genome Wide Association Studies (GWAS) enabled the identification of several loci involved in immune functions as genetic risk factors in MS. Recent data suggest that common genetic variations might modulate the clinical phenotype of MS through a regulation of key pathophysiological pathways.

PERSPECTIVES

Identification of modifier genes might offer an opportunity to explore new relevant therapeutic targets and early prognostic markers. To date, studies of modifier genes in MS are numerous but results are still unclear. This research field may now benefit from large cohorts of patients available for association studies.

CONCLUSION

In this context, we propose a review of epidemiological and association studies of genetic modifying effect in MS.

Multiple sclerosis in Hispanics: a study of clinical disease expression

Background: Hispanics living with multiple sclerosis (MS) in the United States are not well defined.

Objective: To describe the clinical characteristics of MS among Hispanic Whites (HW) in Southern California with those of non-Hispanic Whites (NHW).

Methods: We performed a medical chart review to identify all cases of HW with MS ( n = 125) who were treated at our institution during a 1-year period. We also identified cases of NHW with MS (100 NHW) treated at those clinics. All HW patients were interviewed to ascertain ancestry including detailed migration history. Disease progression was assessed by ambulatory disability and defined as Expanded Disability Status Scale (EDSS) score ≥6.

Results: Compared with NHW, HW were more likely to have a relapsing–remitting form of MS and a younger age of onset (28.4 ± 0.97 years) with presenting symptoms of optic neuritis and transverse myelitis. However, overall ambulatory disability did not differ between HW and NHW. Migration to the US at age >15 years was associated with increased risk of disability in HW.

Conclusions: HW living in the USA may be at risk of developing MS at an earlier age compared with NHW. Migration history can play an important role in the management of HW with MS.

Spinal cord ring enhancement in multiple sclerosis

OBJECTIVE

To describe the clinical and imaging characteristics of spinal cord ring enhancement in multiple sclerosis (MS).

DESIGN

Clinical case series.

SETTING

Academic referral center.

PATIENTS

Twenty patients with MS who had spinal cord ring enhancement were retrospectively identified from 322 cervical and thoracic spinal cord magnetic resonance imaging studies during a 3-year period.

MAIN OUTCOME MEASURES

Demographics, disability, and pattern of enhancement on spinal cord and concomitant brain magnetic resonance imaging results.

RESULTS

Ring enhancement was seen in 20 patients with spinal cord enhancement, most commonly in the cervical cord. Incomplete or "open" ring enhancement was the dominant pattern in 19 of the 20 patients (95%). Concurrent enhancing brain lesions were present in 14 patients, 8 of which (57%) exhibited a ring pattern of enhancement. At the time of imaging, the Expanded Disability Status Scale scores ranged from 1.0 to 7.0 (median score, 3.0).

CONCLUSIONS

Ring enhancement is not an uncommon pattern for spinal cord lesions in MS, occurring with a prevalence of 6.2% (20 of 322 imaging studies). The most common pattern is incomplete ring enhancement in the cervical spinal cord. Recognition of this pattern may improve and expedite the diagnosis of MS and preclude the need for invasive diagnostic interventions.

Multiple sclerosis susceptibility alleles in African Americans

Multiple sclerosis (MS) is an autoimmune demyelinating disease characterized by complex genetics and multifaceted gene-environment interactions. Compared to whites, African Americans have a lower risk for developing MS, but African Americans with MS have a greater risk of disability. These differences between African Americans and whites may represent differences in genetic susceptibility and/or environmental factors. SNPs from 12 candidate genes have recently been identified and validated with MS risk in white populations. We performed a replication study using 918 cases and 656 unrelated controls to test whether these candidate genes are also associated with MS risk in African Americans. CD6, CLEC16a, EVI5, GPC5, and TYK2 contained SNPs that are associated with MS risk in the African American data set. EVI5 showed the strongest association outside the major histocompatibility complex (rs10735781, OR=1.233, 95% CI=1.06-1.43, P-value=0.006). In addition, RGS1 seems to affect age of onset whereas TNFRSF1A seems to be associated with disease progression. None of the tested variants showed results that were statistically inconsistent with the effects established in whites. The results are consistent with shared disease genetic mechanisms among individuals of European and African ancestry.

Differences in the progression of primary progressive multiple sclerosis in Brazilians of African descent versus white Brazilian patients

Recent studies have suggested faster clinical progression and greater disability in multiple sclerosis patients of African descent. This study analysed the effect of ethnicity on progression and disability.

Sixty-five patients with primary progressive multiple sclerosis were selected and classified as being of African descent or white. Time from onset of the disease until reaching Expanded Disability Status Scale grades 3, 6, and 8 was assessed, as well as irreversible disability (Expanded Disability Status Scale grade maintained for ≥6 months).

In the African descent group, the median time to reach Expanded Disability Status Scale 3 was 1 year shorter (1 year vs 2 years, p= 0.02), and to reach Expanded Disability Status Scale 6 was 2 years shorter (3 years vs 5 years, p= 0.01) than in the group of white patients. According to the Kaplan—Meier survival curves, patients of African descent reached every disability stage faster than white patients ( p= 0.03, p = 0.04, and p = 0.03, respectively, for Expanded Disability Status Scale grades 3, 6, and 8).

As in United States and European patients of African descent, the more severe and faster progression of multiple sclerosis seen in Brazilian primary progressive multiple sclerosis patients of African descent suggests a possibly greater effect of ethnicity rather than environment on the progression of multiple sclerosis.

Best practice recommendations for the selection and management of patients with multiple sclerosis receiving natalizumab therapy

Natalizumab, a humanized monoclonal antibody directed against α4-integrin is a first-in-class disease-modifying therapy for the treatment of relapsing multiple sclerosis. Natalizumab is highly effective but has been associated with a risk of progressive multifocal leukoencephalopathy. Since the efficacy of natalizumab in relapsing forms of multiple sclerosis is viewed as superior to first-line agents, a growing number of neurologists are using natalizumab as the treatment of choice for patients with worsening MS. Owing to the recently reported cases of progressive multifocal leukoencephalopathy, a panel of neurologists met in February 2009 to discuss best practices for the use of natalizumab, with the goal of developing consensus-based recommendations on patient management to minimize the risk of progressive multifocal leukoencephalopathy. The panel consisted of a cross section of academic and community neurologists from the United States who treat multiple sclerosis in large centers and have extensive experience with natalizumab (approximating 2000 patient-years combined experience). This paper summarizes the panel's recommendations on the following: (1) appropriate patient selection for natalizumab; (2) routine monitoring and management of adverse events during natalizumab therapy; and (3) clinical vigilance monitoring and risk reduction for progressive multifocal leukoencephalopathy.

Recognizing and treating suboptimally controlled multiple sclerosis: steps toward regaining command

OBJECTIVE

The therapies available today for multiple sclerosis (MS) reduce but do not fully control disease activity. The objective of this article is to review the definitions of and treatments for suboptimally controlled MS and highlight the challenges faced by clinicians to increase awareness of recognizing and managing patients with suboptimally controlled MS.

METHODS

Published literature describing treatment failure, treatment optimization paradigms or algorithms, clinical studies of therapies in patients with suboptimally controlled MS, or case reports of management of patients with suboptimally controlled MS were identified from searches of EMBASE and MEDLINE. This was supplemented with case reports and discussions from an expert panel meeting of MS specialists focused on the diagnosis and treatment of suboptimally controlled MS.

RESULTS

Several groups have created recommendations for evaluating suboptimal response to disease-modifying drugs (DMDs) in MS. Currently no robust evidence-based data exist to guide treatment decisions in patients who have suboptimal response to a particular therapy. In the absence of data, several treatment paradigms for suboptimally controlled MS have been proposed using a step therapy or platform therapy approach. Therapy modifications require consideration of disease- and patient-specific factors while accounting for the risk-benefit profile of the agent(s). Unapproved drugs and combination therapies should be reserved as agents of last resort because of the experimental nature of these treatments.

CONCLUSIONS

In the absence of evidence-based data, identifying and treating MS patients with suboptimal response to the available platform therapies remains challenging. Developing algorithms able to quantify breakthrough disease activity and suboptimal response to DMDs in individual MS patients remains an important target for the MS community. Consideration should be given for all reasons why a particular DMD may not be working for a given patient and for the use of an individualized step therapy.

Optical coherence tomography is less sensitive than visual evoked potentials in optic neuritis

OBJECTIVES

Determine the utility of optical coherence tomography (OCT) to detect clinical and subclinical remote optic neuritis (ON), its relationship to clinical characteristics of ON and visual function, and whether the retinal nerve fiber layer (RNFL) thickness functions as a surrogate marker of global disease severity.

METHODS

Cross-sectional study of 65 subjects with at least 1 clinical ON episode at least 6 months prior. Measures included clinical characteristics, visual acuity (VA), contrast sensitivity (CS), OCT, and visual evoked potentials (VEP).

RESULTS

Ninety-six clinically affected optic nerves were studied. The sensitivity of OCT RNFL after ON was 60%, decreasing further with mild onset and good recovery. VEP sensitivity was superior at 81% (p = 0.002). Subclinical ON in the unaffected eye was present in 32%. VEP identified 75% of all subclinically affected eyes, and OCT identified <20%. RNFL thickness demonstrated linear correlations with VA (r = 0.65) and CS (r = 0.72) but was unable to distinguish visual categories <20/50. RNFL was thinner with severe onset and disease recurrence but was unaffected by IV glucocorticoids. OCT measurements were not related to overall disability, ethnicity, sex, or age at onset. The greatest predictor for RNFL in the unaffected eye was the RNFL in the fellow affected eye.

CONCLUSIONS

Visual evoked potentials (VEP) remains the preferred test for detecting clinical and subclinical optic neuritis. Optical coherence tomography (OCT) measures were unrelated to disability and demographic features predicting a worse prognosis in multiple sclerosis. OCT may provide complementary information to VEP in select cases, and remains a valuable research tool for studying optic nerve disease in populations.

Modification of Multiple Sclerosis Phenotypes by African Ancestry at HLA

BACKGROUND

In those with multiple sclerosis (MS), African American individuals have a more severe disease course, an older age at onset, and more often have clinical manifestations restricted to the optic nerves and spinal cord (opticospinal MS) than white persons.

OBJECTIVE

To determine whether genetic variation influences clinical MS patterns.

DESIGN

Retrospective multicenter cohort study.

PARTICIPANTS

Six hundred seventy-three African American and 717 white patients with MS.

MAIN OUTCOME MEASURES

Patients with MS were genotyped for HLA-DRB1 and HLA-DQB1 alleles. The proportion of European ancestry at HLA was estimated by genotyping single-nucleotide polymorphisms with known significant frequency differences in West African and European populations. These genotypes were correlated with the opticospinal disease phenotype, disability measures, and age at onset.

RESULTS

Subjects with DRB1*15 alleles were twice as likely to have typical MS rather than opticospinal MS (P = .001). Of the subjects with opticospinal MS or a history of recurrent transverse myelitis who were seropositive for anti-aquaporin 4 antibodies (approximately 5%), none carried DRB1*15 alleles (P = .008). Independently of DRB1*15, African ancestry at HLA correlated with disability as measured by the Multiple Sclerosis Severity Score (P < .001) and risk of cane dependency (hazard ratio, 1.36; P < .001); DRB1*15 alleles were associated with a 2.1-year earlier age at onset (P < .001).

CONCLUSIONS

These data indicate that the role of HLA in MS is not limited to disease susceptibility but that genes embedded in this locus also influence clinical outcomes.

Pediatric-onset multiple sclerosis in African-American black and European-origin white patients

Pediatric-onset multiple sclerosis is now recognized, but the association with ethnicity has not been well studied. In a retrospective review at a major teaching facility, 46 pediatric-onset multiple sclerosis patients were identified; of these, 24 were African-American black and 19 were European-origin white. Both groups were similar in mean age at onset (black, 13.6 +/- 3.36 years; white, 13.68 +/- 3.42 years) and total duration of follow-up (black, 42.7 +/- 43.5 months; white, 38.2 +/- 35.3 months), with no significant difference in time to onset of disease-modifying therapy (black, 11.2 +/- 4.7 months; white, 12.4 +/- 5.1 months). The percentage of females was higher in the black than in the white group (83% vs 47%; P = 0.014). The annualized relapse rate was significantly higher in the black than in the white group (1.80 +/- 1.14 vs 1.13 +/- 0.50; P < 0.001). These findings are consistent with data suggesting a more aggressive disease phenotype among African-American blacks with adult-onset multiple sclerosis. Larger multicenter studies are warranted to confirm the findings.

Regional CNS responses to IFN-gamma determine lesion localization patterns during EAE pathogenesis

The localization of inflammatory foci within the cerebellum is correlated to severe clinical outcomes in multiple sclerosis (MS). Previous studies of experimental autoimmune encephalomyelitis (EAE), a model of MS, revealed distinct clinical outcomes correlated with the capacity of the animal to produce IFN-gamma. Outcomes were linked to localization of inflammatory cells in either the spinal cord (wild type [WT]) or the cerebellum and brain stem (IFN-gamma deficient). We demonstrate, using an adoptive transfer system, that the ability of the central nervous system (CNS) to sense pathogenic T cell-produced IFN-gamma during EAE initiation determines the sites of CNS pathogenesis. Transfer of WT Th1 cells into IFN-gamma receptor-deficient mice results in pathogenic invasion of the brain stem and cerebellum with attendant clinical symptoms, which are identical to the disease observed after transfer of IFN-gamma-deficient T cells to WT hosts. Inflammation of the spinal cord associated with classical EAE is abrogated in both IFN-gamma-deficient systems. Cotransfer of CNS antigen-specific WT Th1 cells with IFN-gamma-deficient T cells is sufficient to restore spinal cord invasion and block cerebellar and brain stem invasion. These data demonstrate that interaction between IFN-gamma and host CNS cells during the initiation of EAE can selectively promote or suppress neuroinflammation and pathogenesis.

Impact of disease-modifying treatments in North African migrants with multiple sclerosis in France

Background

Multiple Sclerosis in North African migrants (MS-NA) is more aggressive with mostly primary progressive forms and cerebellar symptoms. Despite an earlier onset in NA patients, the disease progresses more rapidly, with a higher proportion showing incomplete recovery from the first relapse, a shorter time between the first two relapses, a higher number of relapses in the first 5 years, and a shorter time to reach an EDSS of 4.0 and 6.0. We collected data and studied the impact of disease-modifying therapies (DMT) in NA patients with MS, among the 4144 MS patients treated in our MS clinics.

Methods

We performed a descriptive population-based study of MS-NA patients. Data were crossed with expected age- and gender-matched characteristics available in our EDMUS databases for the period 1995–2007.

Results

A total of 133 patients, representing 66% of the MS-NA patients included in the database were identified: mean age at the first documented symptom: 29.7 years; mean time from diagnosis to the beginning of DMT: 1.2 years. 40% of MS-NA patients had an EDSS >3 at the beginning of treatment (vs. 25%; P = 0.002). A majority of patients were treated initially with immunomodulatory drugs (MS-NA: 48% vs. CT: 51%, P = 0.8). NA patients were treated earlier after diagnosis (1.3 years vs. 4.5 years, P = 0.003), with the frequent use of immunosuppressive drugs: for remitting forms, mitoxantrone (18.5% vs. 7.8%, P = 0.0001) and for progressive forms, cyclophosphamide (38% vs. 28%, P = 0.003).

Conclusions

Considering EDSS follow-up during DMT, MS-NA patients appear as responsive as other MS patients to treatment, despite the earlier treatment prescription and the more frequent use of immunosuppressors.

Increased intracranial pressure in a case of pediatric multiple sclerosis

A 15-year-old girl presented to our emergency department with dizziness, anorexia, nausea, and malaise. Clinical examination and magnetic resonance imaging studies showed characteristic features of multiple sclerosis. Surprisingly, a diagnostic lumbar puncture showed significant intracranial hypertension in addition to numerous oligoclonal bands, elevated immunoglobulin G index and immunoglobulin G/albumin ratio in the cerebrospinal fluid. It is proposed that a large burden of active demyelinating disease may cause increased intracranial pressure, thus providing an additional sound rationale for prompt therapeutic administration of intravenous high-dose steroids.