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

Walking performance is worse in black than white people with multiple sclerosis

BACKGROUND

There is emerging evidence for poor health outcomes among Black people with MS, and Black people with MS may have worse walking performance than White counterparts.

PURPOSE

The current study examined if Black participants with MS had slower walking speed (timed 25-foot walk, T25FW) and shorter walking distance (six-minute walk, 6MW) than White participants, and if these differences were accounted for by demographic variables, physical activity, disease/clinical characteristics, and Social Determinants of Health (SDOH).

METHOD

The analysis included samples of Black (N = 105) and White (N = 246) participants with MS who completed the T25FW and 6MW, underwent a neurological exam for generating an Expanded Disability Status Scale (EDSS) score, and provided data on demographic variables (i.e., age and gender), physical activity, disease/clinical characteristics (i.e., EDSS and MS type), and SDOH (i.e., insurance and employment status) as part of screening and baseline data collection for a clinical trial of exercise training in MS.

RESULTS

The Black participants (1.75±3.82 f/s) had a slower T25FW speed (-1.16 f/s, 95 % CI = -2.23, -0.82) than the White participants (2.91±4.97 f/s). The Black participants (842.3 ± 375.7 f) further had a shorter 6MW distance (-119.2 f, 95 % CI = -213.6, -24.7) than the White participants (961.5 ± 339.9 f). The differences in T25FW speed (-0.22 f/s; 95 % CI = -0.40, -0.04) and 6MW distance (-82.2 f; 95 % CI = -158.4, -6.0) were attenuated, but still different when controlling for other variables in multivariable analyses.

CONCLUSION

Black participants with MS had worse walking performance than the White participants. Our results support future research on examining mobility-focused rehabilitation modalities for improving walking performance in Black people with MS.

REGISTRATION

The study was registered on ClinicalTrials.gov on March 19, 2018 (NCT03468868).

Clinical characteristics and disease burden of African, Caribbean, and Black people with multiple sclerosis in Toronto, Canada

BACKGROUND

Different racial and ethnic groups have demonstrated heterogeneity in the clinical course of multiple sclerosis(MS).

OBJECTIVE

We aimed to evaluate disease characteristics in African, Caribbean, and Black people with MS(ACB-MS) followed at a single centre in Toronto, Canada.

METHODS

ACB-MS were compared with age- and sex-matched people with MS (pwMS) of European descent(EUR-MS) identified through the clinic registry.

RESULTS

344 PwMS were included(n = 172 ACB-MS, n = 172 EUR-MS; mean age 43 years, 68 % female). Baseline mean Expanded disability status scale (EDSS) scores (ACB-MS 2.3 ± 2.3 vs. EUR-MS 2.2 ± 2.0, p = 0.38) and subsequent clinical and radiological measures of disease activity were similar between groups, including annualized relapse rate (ARR)(ACB-MS 0.47 ± 0.47 vs. EUR-MS 0.41 ± 0.34, p = 0.2) and most recent EDSS (ACB-MS 2.7 ± 2.2 vs. EUR-MS 2.3 ± 2.1, p = 0.10). However, the proportion of MRI brain demonstrating new disease activity was higher(37% vs. 26 %, p < 0.05) and disability progression greater in ACB-MS vs. EUR-MS(43% vs. 33 %,p < 0.05) but measures of disease severity including MS Severity Score(3.17 vs. 2.58, p = 0.3) and Progression Index(PI) (0.27 vs. 0.30, p = 0.5) were comparable.

CONCLUSION

Disability progression was seen more commonly in ACB-MS, though clinical disease activity and severity were generally comparable between ACB-MS and EUR-MS patients in Toronto, Canada. These findings partially differ from prior studies demonstrating more overtly aggressive MS disease courses in Black and African American PwMS, necessitating further studies to understand how structural determinants of health drive these disparities.

Differential diagnosis of suspected multiple sclerosis: considerations in people from minority ethnic and racial backgrounds in North America, northern Europe, and Australasia

The differential diagnosis of suspected multiple sclerosis has been developed using data from North America, northern Europe, and Australasia, with a focus on White populations. People from minority ethnic and racial backgrounds in regions where prevalence of multiple sclerosis is high are more often negatively affected by social determinants of health, compared with White people in these regions. A better understanding of changing demographics, the clinical characteristics of people from minority ethnic or racial backgrounds, and the social challenges they face might facilitate equitable clinical approaches when considering a diagnosis of multiple sclerosis. Neuromyelitis optica, systemic lupus erythematous, neurosarcoidosis, infections, and cerebrovascular conditions (eg, hypertension) should be considered in the differential diagnosis of multiple sclerosis for people from minority ethnic and racial backgrounds in North America, northern Europe, and Australasia. The diagnosis of multiple sclerosis in people from a minority ethnic or racial background in these regions requires a comprehensive approach that considers the complex interplay of immigration, diagnostic inequity, and social determinants of health.

The relationship between ethnicity and multiple sclerosis characteristics in the United Kingdom: A UK MS Register study

BACKGROUND

Previous studies have suggested differences in multiple sclerosis (MS) severity according to ethnicity.

METHODS

Data were obtained from the UK MS Register, a prospective longitudinal cohort study of persons with MS. We examined the association between self-reported ethnic background and age at onset, symptom of onset and a variety of participant-reported severity measures. We used adjusted multivariable linear regression models to explore the association between ethnicity and impact of MS, and Cox proportional hazards models to assess disability progression.

RESULTS

We analysed data from 17,314 people with MS, including participants from self-reported Black (n = 157) or South Asian (n = 230) ethnic backgrounds. Age at MS onset and diagnosis was lower in those of South Asian (median 30.0) and Black (median 33.0) ethnicity compared with White ethnicity (median 35.0). In participants with online MS severity measures available, we found no statistically significant evidence for an association between ethnic background and physical disability in MS in both cross-sectional and longitudinal analyses.

CONCLUSION

We found no association between ethnic background and MS severity in a large, diverse UK cohort. These findings suggest that other factors, such as socioeconomic status and structural inequalities, may explain previous findings.

Descriptive Analysis of Health Disparities Between Black and White People With Multiple Sclerosis in the Deep South

BACKGROUND

Black people with multiple sclerosis (MS) have a worse disease course and higher rates of progression than White people with MS. Contributing factors to health disparities are understudied.

METHODS

Data were collected retrospectively from the electronic medical records of 500 people with MS treated between 2013 and 2022 at a university comprehensive MS center in a southern state. Multiple logistic regression analyses were used to determine the associations between 2 disability outcomes (ie, low vs high Expanded Disability Status Score [EDSS] and ambulatory assistance [AMB] requirements) and age, sex, body mass index (BMI), MS type, disease duration, hypertension status, diabetes status, smoking status, adjusted gross income, and health insurance type for Black people with MS and White people with MS.

RESULTS

Of the cohort, 39.2% identified as Black people with MS and the rest were White people with MS. Approximately 80% of White people with MS had relapsing MS (RMS) vs almost 90% of Black people with MS. Black people with MS were more likely to have a higher EDSS (OR 5.0, CI 3.0-8.4) and AMB (OR, 2.8; 95% CI, 1.6-4.8) than White people with MS. Among White people with MS, women (OR, 0.5; 95% CI, 0.3-0.9) and people with RMS (OR, 0.13; 95% CI 0.06-0.3) were less likely to have higher EDSS scores. Among Black people with MS, neither female sex nor RMS status was associated with a lower risk of having a higher EDSS (OR, 0.685; P = .43 and OR, 0.394; P = .29, respectively).

CONCLUSIONS

The disparity in disability outcomes between Black people with MS and White people with MS may be driven by more disabling courses for Black people with RMS and by female sex, though further study is needed to determine causes for this outcome.

Podcast on Identifying and Understanding Barriers to Care in Underserved Populations With MS in the United States

Multiple sclerosis (MS) can affect people from all racial and ethnic backgrounds, but, historically, the incidence of MS in the United States was thought to be highest in White individuals. More recent data suggest that the incidence of MS in Black or African American individuals is comparable to that in White individuals. In Hispanic or Latino individuals, incidence of MS is lower, but age of onset may be earlier compared with White individuals. Additionally, there are important differences in MS disease severity, disease progression, and mortality in Black or African American and Hispanic or Latino populations. Compared with their White counterparts, individuals from these underrepresented groups are more likely to be affected by MS in specific areas of the nervous system, such as accelerated loss of retinal and brain tissue in Black or African American individuals and optic neuritis in Hispanic individuals. Additionally, Black or African American individuals with MS tend to have an aggressive disease course, earlier disability, and higher risk of requiring ambulatory assistance. Although these differences may be attributed to genetic factors, systemic racism and biases and barriers to accessing care may perpetuate health disparities. Moreover, non-White communities remain broadly underrepresented in clinical trials; however, it is vital that these populations are appropriately represented so that any potential differences in drug efficacy or safety implications are detected. Thus, it is important to increase awareness of MS in these populations. In this podcast, the authors discuss characteristics of MS in Black or African American and Hispanic or Latino populations, identify barriers to care, and propose solutions to improve access to MS care in these populations. MP4 (358385 KB).

Multiple Sclerosis in Black and Hispanic Populations: Serving the Underserved

Multiple sclerosis has historically been characterized as a disease that affects young women of European ancestry, but recent studies indicate that the incidence and prevalence of the disease is much higher in Black and Hispanic populations than previously recognized. There is evidence that there is a more severe disease course in these populations. , but the intersection of genetic underpinnings and social determinants of health (SDOH) is poorly understood due to the lack of diversity in clinical research. Improving health disparities will involve multiple stakeholders in efforts to improve SDOH and raise awareness about research involvement and the importance of developing personalized health care plans to combat this disease.

Modifiable risk factors for multiple sclerosis have consistent directions of effect across diverse ethnic backgrounds: a nested case-control study in an English population-based cohort

BACKGROUND

Multiple sclerosis is a leading cause of non-traumatic neurological disability among young adults worldwide. Prior studies have identified modifiable risk factors for multiple sclerosis in cohorts of White ethnicity, such as infectious mononucleosis, smoking, and obesity during adolescence/early adulthood. It is unknown whether modifiable exposures for multiple sclerosis have a consistent impact on risk across ethnic groups.

AIM

To determine whether modifiable risk factors for multiple sclerosis have similar effects across diverse ethnic backgrounds.

METHODS

We conducted a nested case-control study using data from the UK Clinical Practice Research Datalink. Multiple sclerosis cases diagnosed from 2001 until 2022 were identified from electronic healthcare records and matched to unaffected controls based on year of birth. We used stratified logistic regression models and formal statistical interaction tests to determine whether the effect of modifiable risk factors for multiple sclerosis differed by ethnicity.

RESULTS

We included 9662 multiple sclerosis cases and 118,914 age-matched controls. The cohort was ethnically diverse (MS: 277 South Asian [2.9%], 251 Black [2.6%]; Controls: 5043 South Asian [5.7%], 4019 Black [4.5%]). The age at MS diagnosis was earlier in the Black (40.5 [SD 10.9]) and Asian (37.2 [SD 10.0]) groups compared with White cohort (46.1 [SD 12.2]). There was a female predominance in all ethnic groups; however, the relative proportion of males was higher in the South Asian population (proportion of women 60.3% vs 71% [White] and 75.7% [Black]). Established modifiable risk factors for multiple sclerosis-smoking, obesity, infectious mononucleosis, low vitamin D, and head injury-were consistently associated with multiple sclerosis in the Black and South Asian cohorts. The magnitude and direction of these effects were broadly similar across all ethnic groups examined. There was no evidence of statistical interaction between ethnicity and any tested exposure, and no evidence to suggest that differences in area-level deprivation modifies these risk factor-disease associations. These findings were robust to a range of sensitivity analyses.

CONCLUSIONS AND RELEVANCE

Established modifiable risk factors for multiple sclerosis are applicable across diverse ethnic backgrounds. Efforts to reduce the population incidence of multiple sclerosis by tackling these risk factors need to be inclusive of people from diverse ethnicities.

Ethnic disparities in the epidemiological and clinical characteristics of multiple sclerosis

BACKGROUND

Multiple Sclerosis (MS) is a neuroinflammatory disorder which affects 2.8 million people world-wide. A growing body of evidence shows ethnic disparities in MS. This review aims to evaluate differences, based upon ethnic background, in the incidence, prevalence, disease course, and efficacy of disease-modifying therapies (DMTs) among people with MS (PwMS).

METHOD

Ethnicities were classified as White, Black, Hispanic, Asian, and Middle Eastern and North African (MENA). A literature search was conducted using the PubMed search engine to identify articles on MS and ethnicity that were published in the English language between 01/01/2005 and 31/05/2022.

RESULTS

101 studies met all inclusion criteria. Although the incidence and prevalence of MS varied among ethnicities, findings were inconsistent and depended on the continent of the study. Ethnicity may have an impact on the disease course. PwMS from Black, Hispanic, and MENA, but not Asian ethnicities, appeared to accumulate physical disability at a faster rate than those from White ethnicity. Although there was a lack of studies evaluating the relative safety and efficacy of DMTs among various ethnicities, interferon-beta was found to be less efficacious in PwMS from Black ethnicity.

CONCLUSIONS

Further studies, with more uniform definitions of ethnicity are required to comprehensively understand ethnic disparities in MS, in particular to identify underlying causes, to facilitate the delivery of personalised medical care and avoid inequity.

Treatment Patterns by Race and Ethnicity in Newly Diagnosed Persons with Multiple Sclerosis

BACKGROUND

Non-Hispanic Black and Hispanic persons with MS (pwMS) are more likely to experience rapid disease progression and severe disability than non-Hispanic White pwMS; however, it is unknown how the initiation of high-efficacy disease-modifying therapies (DMTs) differs by race/ethnicity. This real-world study describes DMT treatment patterns in newly diagnosed pwMS in the United States (US) overall and by race/ethnicity.

METHODS

This retrospective analysis used the US Optum Market Clarity claims/electronic health records database (January 2015-September 2020). pwMS who were first diagnosed in 2016 or later and initiated any DMT in the two years following diagnosis were included. Continuous enrollment in the claims data for ≥ 12 months before and ≥ 24 months after diagnosis was required. Treatment patterns 2 years after diagnosis were analyzed descriptively overall and by race/ethnicity.

RESULTS

The sample included 682 newly diagnosed and treated pwMS (non-Hispanic Black, n = 99; non-Hispanic White, n = 479; Hispanic, n = 35; other/unknown race/ethnicity, n = 69). The mean time from diagnosis to DMT initiation was 4.9 months in all pwMS. Glatiramer acetate and dimethyl fumarate were the most common first-line DMTs in non-Hispanic Black (28% and 20% respectively) and Hispanic pwMS (31%, 29%); however, glatiramer acetate and ocrelizumab were the most common in non-Hispanic White pwMS (33%, 18%). Use of first-line high-efficacy DMTs was limited across all race/ethnicity subgroups (11-29%), but uptake increased in non-Hispanic Black and White pwMS over the study period.

CONCLUSION

Use of high-efficacy DMTs was low across all race/ethnicity subgroups of newly diagnosed pwMS in the US, including populations at a greater risk of experiencing rapid disease progression and severe disability.

Cerebellar pathology in multiple sclerosis and experimental autoimmune encephalomyelitis: current status and future directions

Recent decades have witnessed significant progress in understanding mechanisms driving neurodegeneration and disease progression in multiple sclerosis (MS), but with a focus on the cerebrum. In contrast, there have been limited studies of cerebellar disease, despite the common occurrence of cerebellar symptoms in this disorder. These rare studies, however, highlight the early cerebellar involvement in disease development and an association between the early occurrence of cerebellar lesions and risk of worse prognosis. In parallel developments, it has become evident that far from being a region specialized in movement control, the cerebellum plays a crucial role in cognitive function, via circuitry connecting the cerebellum to association areas of the cerebrum. This complexity, coupled with challenges in imaging of the cerebellum have been major obstacles in the appreciation of the spatio-temporal evolution of cerebellar damage in MS and correlation with disability and progression. MS studies based on animal models have relied on an induced neuroinflammatory disease known as experimental autoimmune encephalomyelitis (EAE), in rodents and non-human primates (NHP). EAE has played a critical role in elucidating mechanisms underpinning tissue damage and been validated for the generation of proof-of-concept for cerebellar pathological processes relevant to MS. Additionally, rodent and NHP studies have formed the cornerstone of current knowledge of functional anatomy and cognitive processes. Here, we propose that improved insight into consequences of cerebellar damage in MS at the functional, cellular and molecular levels would be gained by more extensive characterization of EAE cerebellar pathology combined with the power of experimental paradigms in the field of cognition. Such combinatorial approaches would lead to improved potential for the development of MS sensitive markers and evaluation of candidate therapeutics.

Real-World Safety and Effectiveness After 5 Years of Dimethyl Fumarate Treatment in Black and Hispanic Patients with Multiple Sclerosis in ESTEEM

INTRODUCTION

Multiple sclerosis (MS) clinical trials have included low numbers of patients from racial and ethnic minority populations; therefore, it is uncertain whether differences exist in response to disease-modifying therapies. We evaluated the real-world safety and effectiveness of dimethyl fumarate (DMF) treatment over 5 years in four patient cohorts: Black, non-Black, Hispanic, and non-Hispanic people with relapsing-remitting MS.

METHODS

ESTEEM is an ongoing, 5-year, multinational, prospective study evaluating the long-term safety and effectiveness of DMF in people with MS. The analysis included patients newly prescribed DMF in routine practice at 393 sites globally.

RESULTS

Overall, 5251 patients were analyzed (220 Black, 5031 non-Black; 105 Hispanic, 5146 non-Hispanic). Median (min-max) months of follow-up was 32 (0-72) for Black, 29 (1-77) for Hispanic, and 41 (0-85) for both the non-Black and non-Hispanic populations. In total, 39 (18%) Black and 29 (28%) Hispanic patients reported adverse events leading to treatment discontinuation versus 1126 (22%) non-Black and 1136 (22%) non-Hispanic patients; gastrointestinal disorders were the most common in all subgroups. Median lymphocyte counts decreased by 37% in Black, 40% in non-Black, 10% in Hispanic, and 39% in non-Hispanic patients in the first year, then remained stable and above the lower limit of normal in most patients. Annualized relapse rates (ARRs) (95% confidence intervals) up to 5 years were 0.054 (0.038-0.078) for Black, 0.077 (0.072-0.081) for non-Black, 0.069 (0.043-0.112) for Hispanic, and 0.076 (0.072-0.081) for non-Hispanic populations, representing reductions of 91-92% compared with ARR 12 months before study entry (all p < 0.0001).

CONCLUSION

The safety profile of DMF in these subgroups was consistent with the overall ESTEEM population. Relapse rates remained low in Black and Hispanic patients, and consistent with non-Black and non-Hispanic patients. These data demonstrate a comparable real-world treatment benefit of DMF in Black and Hispanic patients.

TRIAL REGISTRATION

ClinicalTrials.gov identifier NCT02047097.

Social determinants of health and disparate disability accumulation in a cohort of Black, Hispanic, and White patients with multiple sclerosis

BACKGROUND

Black and Hispanic patients with multiple sclerosis (MS) have been shown to accumulate greater multiple sclerosis-associated disability (MSAD) than White patients. Disparities in social determinants of health (SDOH) among these groups have also been reported.

OBJECTIVE

To determine the extent to which associations of race and ethnicity with MSAD may be attributable to differences in SDOH.

METHODS

Retrospective chart analysis of patients at an academic MS center grouped by self-identified Black (n = 95), Hispanic (n = 93), and White (n = 98) race/ethnicity. Individual patient addresses were geocoded and matched with neighborhood-level area deprivation index (ADI) and social vulnerability index (SVI).

RESULTS

Average Expanded Disability Status Scale (EDSS) scores at last-recorded evaluations of White patients (1.7 ± 2.0) were significantly lower than Black (2.8 ± 2.4, p = 0.001) and Hispanic (2.6 ± 2.6, p = 0.020) patients. Neither Black race nor Hispanic ethnicity was significantly associated with EDSS in multivariable linear regression models that included individual-level SDOH indicators and either ADI or SVI.

CONCLUSION

Black race and Hispanic ethnicity are not significantly associated with EDSS in models that include individual and neighborhood-level SDOH indicators. Further research should elucidate mechanisms by which structural inequities affect MS disease course.

Diversity, Equity, and Inclusion in the Multiple Sclerosis Community: A Call to Action

Many medical organizations have begun to confront the longstanding problem of inequalities in health care delivery and the undeniable effect of disparities on health outcomes. The Consortium of Multiple Sclerosis Centers (CMSC) recognizes that disparities affect the lives of many people with multiple sclerosis (MS) and acknowledges the need to address this as an organization. The CMSC recently (1) appointed a task force, (2) conducted a survey of its membership, (3) commissioned this review article and call to action, and (4) formulated a mission statement on diversity, equity, and inclusion (DEI), which was adopted by the CMSC's Board of Governors in March 2023. This paper summarizes recent literature on health care disparities in MS, particularly those relating to race/ethnicity, sexual orientation, and gender identity. It presents findings from CMSC's survey of members' awareness of DEI issues, the need for education and resources for MS care providers, and existing institutional policies on DEI in the members' practice settings. It also presents the task force's recommendations for next steps, which includes the goal of greater diversity in the MS workforce of the future. The CMSC will continue to revisit DEI policies and practices over time with the goal of motivating greater awareness, momentum, and positive changes within the MS community.

Neuron-binding antibody responses are associated with Black ethnicity in multiple sclerosis during natalizumab treatment

Multiple sclerosis is an inflammatory degenerative condition of the central nervous system that may result in debilitating disability. Several studies over the past twenty years suggest that multiple sclerosis manifests with a rapid, more disabling disease course among individuals identifying with Black or Latin American ethnicity relative to those of White ethnicity. However, very little is known about immunologic underpinnings that may contribute to this ethnicity-associated discordant clinical severity. Given the importance of B cells to multiple sclerosis pathophysiology, and prior work showing increased antibody levels in the cerebrospinal fluid of Black-identifying, compared to White-identifying multiple sclerosis patients, we conducted a cohort study to determine B cell subset dynamics according to both self-reported ethnicity and genetic ancestry over time. Further, we determined relationships between ethnicity, ancestry, and neuron-binding IgG levels. We found significant associations between Black ethnicity and elevated frequencies of class-switched B cell subsets, including memory B cells; double negative two B cells; and antibody-secreting cells. The frequencies of these subsets positively correlated with West African genetic ancestry. We also observed significant associations between Black ethnicity and increased IgG binding to neurons. Our data suggests significantly heightened T cell-dependent B cell responses exhibiting increased titres of neuron-binding antibodies among individuals with multiple sclerosis identifying with the Black African diaspora. Factors driving this immunobiology may promote the greater demyelination, central nervous system atrophy and disability more often experienced by Black-, and Latin American-identifying individuals with multiple sclerosis.

Demographics and baseline disease characteristics of Black and Hispanic patients with multiple sclerosis in the open-label, single-arm, multicenter, phase IV CHIMES trial

BACKGROUND

Black/African American patients with multiple sclerosis (BpwMS) and Hispanic/Latino patients with multiple sclerosis (HpwMS), who historically have been underrepresented in multiple sclerosis (MS) clinical trials, exhibit greater disease severity and more rapid disease progression than White patients with MS (WpwMS). The lack of diversity and inclusion in clinical trials, which may be due to barriers at the system, patient and study levels, impacts the ability to effectively assess risks, benefits and treatment responses in a generalized patient population.

METHODS

CHIMES (Characterization of Ocrelizumab in Minorities With Multiple Sclerosis), an open-label, single-arm, multicenter, phase IV study of self-identified BpwMS and HpwMS aged 18-65 years with relapsing MS and an Expanded Disability Status Score (EDSS) of ≤5.5, was developed in collaboration with patients with MS, national advocacy groups and clinical researchers. Patients were enrolled at study centers across the US, including Puerto Rico, and 1 site in Kenya.

RESULTS

A total of 182 patients enrolled in CHIMES: 113 (62.1%) were BpwMS, and 69 (37.9%) were HpwMS; the mean (SD) baseline EDSS score was 2.4 (1.4), and 62.6% of patients were treatment naive. Using the pooled non-BpwMS/HpwMS group in the OPERA ocrelizumab trials as a reference population, patients enrolled in CHIMES were younger, had a higher mean body mass and had a greater T2 lesion volume but similar T2 lesion number on MRI.

CONCLUSION

BpwMS and HpwMS have been consistently underrepresented in clinical trials, limiting the understanding of disease biology and response to treatment in this population. Data from the CHIMES study revealed differences in demographics and some baseline disease characteristics and disease burden between BpwMS and HpwMS vs WpwMS. These differences could have an impact when assessing clinical outcomes in BpwMS and HpwMS.

CLINICALTRIALS

GOV IDENTIFIER

NCT04377555.

Long-Term Effectiveness and Safety of Natalizumab in African American and Hispanic/Latino Patients with Early Relapsing-Remitting Multiple Sclerosis: STRIVE Data Analysis

INTRODUCTION

In STRIVE, natalizumab treatment demonstrated effectiveness in clinical, magnetic resonance imaging (MRI), and patient-reported outcomes (PROs) in patients with early relapsing-remitting multiple sclerosis (RRMS). This post hoc analysis examined the effectiveness and safety of natalizumab in patients who self-identified as either Black/African American (AA) or Hispanic/Latino.

METHODS

Clinical, MRI, and PROs were assessed for the Black/AA subgroup (n = 40) and compared with the non-Hispanic White subgroup (n = 158). As a result of the very small sample size, outcomes for the Hispanic/Latino subgroup (n = 18) were assessed separately, including a sensitivity analysis with Hispanic/Latino patients who completed the 4-year study on natalizumab.

RESULTS

Clinical, MRI, and PROs were comparable between the Black/AA and non-Hispanic White subgroups except for MRI outcomes at year 1. A higher proportion of non-Hispanic White than Black/AA patients achieved MRI no evidence of disease activity (NEDA; 75.4% vs. 50.0%, p = 0.0121) and no new or newly enlarging T2 lesions (77.6% vs. 50.0%, p = 0.0031) at year 1; these differences were not observed in years 2-4 of the study. For the Hispanic/Latino subgroup in the intent-to-treat population, 46.2% and 55.6% achieved NEDA at years 1 and 2; 66.7% and 90.0% achieved clinical NEDA at years 3 and 4. Annualized relapse rate was reduced by 93.0% at year 1 versus the year before natalizumab initiation; this reduction was maintained throughout the study. Over 4 years, 37.5-50.0% of patients had a clinically meaningful improvement in their Symbol Digit Modalities Test score, and 81.8-100.0% and 90.9-100.0% had stable/improved Multiple Sclerosis Impact Scale-29 physical and psychological scores, respectively. Similar results were observed in the sensitivity analysis with Hispanic/Latino subgroup of the 4-year natalizumab completers.

CONCLUSION

These results highlight the effectiveness and safety of natalizumab in patients with early RRMS who self-identified as Black/AA or Hispanic/Latino.

CLINICALTRIALS

GOV: NCT01485003.

Subtypes of relapsing-remitting multiple sclerosis identified by network analysis

We used network analysis to identify subtypes of relapsing-remitting multiple sclerosis subjects based on their cumulative signs and symptoms. The electronic medical records of 113 subjects with relapsing-remitting multiple sclerosis were reviewed, signs and symptoms were mapped to classes in a neuro-ontology, and classes were collapsed into sixteen superclasses by subsumption. After normalization and vectorization of the data, bipartite (subject-feature) and unipartite (subject-subject) network graphs were created using NetworkX and visualized in Gephi. Degree and weighted degree were calculated for each node. Graphs were partitioned into communities using the modularity score. Feature maps visualized differences in features by community. Network analysis of the unipartite graph yielded a higher modularity score (0.49) than the bipartite graph (0.25). The bipartite network was partitioned into five communities which were named fatigue, behavioral, hypertonia/weakness, abnormal gait/sphincter, and sensory, based on feature characteristics. The unipartite network was partitioned into five communities which were named fatigue, pain, cognitive, sensory, and gait/weakness/hypertonia based on features. Although we did not identify pure subtypes (e.g., pure motor, pure sensory, etc.) in this cohort of multiple sclerosis subjects, we demonstrated that network analysis could partition these subjects into different subtype communities. Larger datasets and additional partitioning algorithms are needed to confirm these findings and elucidate their significance. This study contributes to the literature investigating subtypes of multiple sclerosis by combining feature reduction by subsumption with network analysis.

Disability outcomes in early-stage African American and White people with multiple sclerosis

BACKGROUND

Factors driving differences in disease burden between African American and White people with multiple sclerosis (pwMS) remain unclear. Here, we explored whether differences in disability outcomes could be observed after controlling for major sociodemographic factors and comorbidities, and assessed the presence of a possible interaction between MS and race.

METHODS

In this cross-sectional study, 120 pwMS within 6 years from disease onset and 82 healthy controls between 18 and 70 years of age, self-identified as either African American or White, were prospectively enrolled. Inclusion criteria for pwMS were: diagnosis of MS according to the revised McDonald criteria, relapsing-remitting phenotype and Expanded Disability Status Scale (EDSS) < 6.5. Study outcomes included: (i) global disability (EDSS); (ii) quantitative mobility and leg function (Timed 25 Foot Walk Test-T25FWT); (iii) quantitative finger dexterity (9-Hole Peg Test-9HPT); (iv) cognitive efficiency and speed performance (Symbol Digit Modalities Test-SDMT). Differences in disability outcomes were assessed employing multivariable linear regression models. Based on their association with MS or disability, covariates included age, gender, race, years of education, total income, body mass index, comorbidities. The interaction between MS and race on disability outcomes was estimated via relative excess risk of interaction and attributable proportion.

RESULTS

Accounting for age, gender, total income, education, body mass index and comorbidities, African American pwMS showed significantly worse performances in manual dexterity and cognition than White pwMS (White pwMS coeff. 3.24, 95% CI 1.55, 4.92 vs African American pwMS coeff. 5.52, 95% CI 3.55, 7.48 and White pwMS coeff. -5.87, 95% CI -8.86, -2.87 vs African American pwMS coeff. -7.99, 95% CI -11.58,-4.38). MS and race independently contributed to the observed gradient in disability severity.

CONCLUSIONS

Complex social disparities and systemic racism might contribute to clinical heterogeneity in MS.

Social cognitive correlates of device-measured and self-reported physical activity in Black and White individuals with multiple sclerosis

BACKGROUND

There is increasing research interest regarding physical activity behavior among persons with multiple sclerosis (MS), yet there is little known about physical activity and its correlates in Black persons with MS.

OBJECTIVE

This cross-sectional study assessed associations among social cognitive theory (SCT) variables and device-measured and self-reported physical activity in samples of Black and White persons with MS.

METHODS

Participants included 67 Black and 141 White persons with MS who wore an ActiGraph accelerometer on a belt around the waist measuring moderate-to-vigorous physical activity (MVPA) for seven days and completed a battery of questionnaires. Questionnaires included demographic and clinical characteristics, leisure-time exercise, exercise self-efficacy, overcoming barriers self-efficacy, function, social support, exercise outcome expectations, and goal setting and planning.

RESULTS

Black participants with MS engaged in significantly less MVPA, but not sedentary behavior or light physical activity, than the White participants with MS. Black participants further had significantly lower levels of exercise self-efficacy and outcome expectations than the White sample. All SCT correlates were significantly correlated with self-reported physical activity, but only exercise and barriers self-efficacy, perceived function, and exercise goal setting were associated with device-measured MVPA. The difference in physical activity between Black and White participants with MS was accounted for by differences in exercise self-efficacy and outcome expectations.

CONCLUSIONS

Researchers should consider developing behavioral interventions that target exercise self-efficacy and outcome expectations as SCT variables for increasing physical activity in Black persons with MS.

Towards a global view of multiple sclerosis genetics

Multiple sclerosis (MS) is a neuroimmunological disorder of the CNS with a strong heritable component. The genetic architecture of MS susceptibility is well understood in populations of European ancestry. However, the extent to which this architecture explains MS susceptibility in populations of non-European ancestry remains unclear. In this Perspective article, we outline the scientific arguments for studying MS genetics in ancestrally diverse populations. We argue that this approach is likely to yield insights that could benefit individuals with MS from all ancestral groups. We explore the logistical and theoretical challenges that have held back this field to date and conclude that, despite these challenges, inclusion of participants of non-European ancestry in MS genetics studies will ultimately be of value to all patients with MS worldwide.

Pharmacokinetics/pharmacodynamics by race: Analysis of a peginterferon β-1a phase 1 study

BACKGROUND

Black/African American participants are underrepresented in clinical trials for multiple sclerosis but can experience a greater burden of disease than other racial groups in the United States. A phase 1, open-label, crossover study that demonstrated bioequivalence of subcutaneous and intramuscular injection of peginterferon β-1a in healthy volunteers enrolled similar proportions of Black and White participants, enabling a post hoc subgroup analysis comparing these groups.

METHODS

Peginterferon β-1a (125 μg) was administered by subcutaneous or intramuscular injection, followed by a washout period before a second injection using the alternative method. The primary pharmacokinetic and pharmacodynamic endpoints were maximum observed concentration (C_max) and area under the concentration-time curve from hour 0 to infinity (AUC_inf) of study drug and serum concentration of neop-terin, respectively. Safety and tolerability were included as secondary endpoints.

FINDINGS

This analysis included 70 (51.5%) Black and 59 (43.3%) White participants. Peginterferon β-1a C_max was 29.8% higher in Black than in White participants following subcutaneous administration but was similar following intramuscular administration. Mean AUC_inf was 31.0% and 11.8% greater in Black than in White participants with subcutaneous and intramuscular administration, respectively. Pharmacodynamics and safety signals were similar between groups, although Black participants reported numerically fewer adverse events.

CONCLUSIONS

No clinically meaningful differences were identified between Black and White participants related to peginterferon β-1a administration, supporting the approved dose of 125 μg/mL peginterferon β-1a. Future clinical studies should include sufficiently diverse populations to ensure accurate assessments of treatment response.

FUNDING

Funding for medical writing support was provided by Biogen (Cambridge, MA, USA).

Advancing Care and Outcomes for African American Patients With Multiple Sclerosis

Multiple sclerosis (MS) has historically been underdiagnosed and undertreated among African Americans. Recent evidence suggests that African Americans with MS have a different clinical presentation, increased disease incidence and burden, and worse long-term outcomes vs their White counterparts. Due to limited data available for African Americans in MS clinical trials, it is difficult to make informed, generalizable conclusions about the natural history, prognosis, and therapeutic response in this population. In this narrative review, we highlight the nature and magnitude of the health disparities experienced by African Americans with MS and underscore the pressing need to increase knowledge about and understanding of MS disease manifestations in this group. In addition, we describe the mission and objectives of the recently established National African Americans with Multiple Sclerosis Registry, which is intended to be a platform to advance the care of African Americans with MS and address health disparities they may experience.

Perceptions and Preferences Regarding Multiple Sclerosis Research Among Racial and Ethnic Groups

BACKGROUND

For unclear reasons, minorities have been historically underrepresented in multiple sclerosis (MS) clinical trials. We hypothesized that different perceptions and preferences about research participation among racial and ethnic groups contribute to this imbalance.

METHODS

Members of the MS Minority Research Engagement Partnership Network developed a Web-based survey in English and Spanish on research impressions, concerns, and preferences regarding study attributes among people with MS. Invitations to take the survey were distributed by network members and partner organizations.

RESULTS

We included 2599 participants with MS (2111 White, 215 African American; 188 Hispanic). Consistently disliked study attributes included potential harms to health and confusing study information. Compared with White and non-Hispanic participants, respectively, African American (odds ratio [OR] = 2.05, P ≤ .001) and Hispanic (OR = 1.79, P = .003) participants were more concerned about being used by the research team. Hispanic participants were more concerned about research participation carrying risks to their legal status (OR = 1.70, P = .001). Hispanic (OR = 3.18, P ≤ .001) and African American (OR = 5.51, P ≤ .001) participants were more likely to prefer for the study to benefit their own racial/ethnic group. A top concern across all groups was not being fully informed about the research.

CONCLUSIONS

We found strong support for research across racial and ethnic groups; however, minority groups have specific concerns regarding mistrust, receiving poor-quality care, unemployment, health insurance, and legal status. Investigators wanting to recruit a diverse study population are advised to show how they have addressed these concerns and to communicate how the research will advance the science and literature and result in better care and/or other benefits to underrepresented communities.

Asian and African/Caribbean AQP4-NMOSD patient outcomes according to self-identified race and place of residence

BACKGROUND

Neuromyelitis optica spectrum disorder (NMOSD) is an autoimmune astrocytopathy characterized by aquaporin-4 antibodies, whose prognosis is influenced by onset age, race, environmental exposures and immunosuppression. Distinguishing the contribution of environment from genetics is challenging. We aimed to compare neuromyelitis optica spectrum disorder (NMOSD) patient outcomes according to self-identified racial group and place of residence.

METHODS

This retrospective analysis of prospectively collected data included non-white anti-aquaporin-4 antibody positive NMOSD patients under follow-up from 15 centers [United Kingdom, France, Germany, Denmark, Martinique, United States of America, Japan, South Korea, Singapore, Thailand, China (including Hong Kong) and India]. Racial groups were designated: African/Caribbean; South Asian; East Asian (including Southeast Asia). Patients from these racial groups residing outside Africa/Caribbean or Asia were compared with those living in the Caribbean or the Asian areas. Kaplan-Meier survival curves and Cox models were generated using time to sustained Expanded Disability Status Scale≥6.0 or death; time to sustained Kurtzke Visual Function Score≥3.0 or a composite endpoint of all three.

RESULTS

Among 821 patients, African/Caribbean patients (n = 206) had the shortest time to immunosuppression and higher visual disability at onset. South Asian patients (n = 65) were younger, had lower visual disability at onset and higher mortality rate. East Asians (n = 550) had the lowest relapse rate and lowest accrued motor disability. Survival analysis of African/Caribbean outside Africa/Caribbean vs those in the Caribbean showed a significant difference in the composite endpoint (p = 0.024,log-rank test), not apparently related to treatment differences. No significant differences between native and those residing outside Asia were found for other racial groups.

CONCLUSION

This NMOSD study reports the effects of place of residence on the outcomes in different races. Place of residence may not be a significant driver of disability among Asian patients, while it may influence African/Caribbean patient outcomes. Validating these findings could help distinguish between genetic causes and potentially modifiable environmental factors.

Multiple sclerosis in Kenya: Demographic and clinical characteristics of a registry cohort

Background

Multiple Sclerosis (MS) is the leading cause of non-traumatic neurological disability in young adults. There is limited literature regarding the burden of MS in sub-Saharan Africa (SSA).

Objective

To describe the demographic and clinical characteristics of patients with MS (PwMS) presenting to a tertiary referral hospital in Nairobi.

Methods

We conducted a retrospective descriptive study for PwMS presenting to Aga Khan University Hospital, Nairobi from 2008–2018.

Results

99 cases met the diagnostic criteria for MS with a male to female ratio of 1:4. Majority (68.7%) of PwMS were indigenous Africans with a mean age of onset of 30.7 years. Mean duration from symptom onset to first neuro-imaging was 5.04 years. Only 33% of patients had sensory symptoms at onset whereas 54.5% had vitamin D deficiency/insufficiency. Majority (79.5%) had relapsing remitting MS (RRMS) and 56.6% were initiated on disease modifying therapy (DMT). Only 21.2% of patients on DMT were non-compliant. Patients with RRMS were more likely to be initiated on DMT at our hospital (p < 0.001).

Conclusion

Clinical characteristics of these patients largely resemble those of other SSA cohorts and African American patients. There was a delay between symptom onset and neuroimaging. There were also issues with DMT compliance.

Cortical surface thickness, subcortical volumes and disability between races in relapsing-remitting multiple sclerosis

BACKGROUND

The interplay between cortical surface thickness (CTh), subcortical volumes (SCV) and disability in patients with relapsing remitting multiple sclerosis (RRMS) is still not clear.

OBJECTIVE

To examine the relationship between CTh, SCV, and disability and investigate differences in CTh, SCV and disability between African Americans (AA) and Caucasian Americans (CA).

METHODS

Sixty-five RRMS (33AA, 32 CA) participants underwent Expanded Disability Status Scale and Multiple Sclerosis Functional Composite (MSFC) assessments, including timed 25-foot walk (T25FW), nine-hole peg test (9HPT) on dominant (D) and non-dominant hand (ND) and paced auditory serial addition test (PASAT-3). Symbol digit modalities test (SDMT) was also administered. All participants underwent 3T brain MRI. CTh was measured in the Frontal (FA), Parietal (PA), Temporal (TA), Occipital (OA), Cingulate (CA), and Global (GA) cortical surface areas (CSA). SCV measurements included Thalamus (TV), Caudate (CV), Putamen (PV), Pallidum (PaV), Hippocampus (HV), Amygdala (AV), Accumbens (AcV), Brain Stem (BSV), and Deep Gray Matter Total Volume (DGMTV). A general linear model with multivariate analysis (MANOVA) was used to determine the differences between the two cohorts (SPSS vs 25). Spearman rank correlation analysis was performed to investigate the relationship between CTh and MSFC.

RESULTS

AA have significantly decreased FA, PA, TA, GA CTh compared to CA (p = 0.004, p = 0.018, p = 0.013, p = 0.015, respectively). SCV measurements were not significantly different. Only in CA, the MSFC measures correlate significantly with regional CSA CTh. In both races and in the entire group, T25FW correlates with TV, PV, AV, AcV and DGMTV (p < 0.05). Only in AA and the entire cohort, PASAT-3 correlates with TV and AcV(p = 0.041, p = 0.006, p = 0.006, p = 0.000 respectively).

CONCLUSIONS

Differences in CSA CTh reinforce the different disease pathobiology between AA and CA. Regional CTh may represent a useful biomarker related to multi-domain disability only in CA, while in AA DGM injury might be a more important contributor to disability. Longitudinal, large-scale studies are warranted to confirm our findings.

Real-World Safety and Effectiveness of Dimethyl Fumarate in Black or African American Patients with Multiple Sclerosis: 3-Year Results from ESTEEM

INTRODUCTION

Black or African American (black/AA) patients with multiple sclerosis (MS) are reported to exhibit greater disease severity compared with non-black or non-AA patients. Whether differences exist in response to MS disease-modifying therapies remains uncertain, as MS clinical trials have included low numbers of non-white patients. We evaluated real-world safety and effectiveness of dimethyl fumarate (DMF) on MS disease activity in black/AA patients.

METHODS

ESTEEM is an ongoing, 5-year, multinational, prospective study evaluating long-term safety and effectiveness of DMF in patients with MS. This interim analysis included patients newly prescribed DMF in routine practice at 394 sites globally.

RESULTS

Overall, 4897 non-black/non-AA and 187 black/AA patients were analyzed; median (range) follow-up 18 (2-37) months. Unadjusted annualized relapse rates (ARRs) for 12 months before DMF initiation versus 36 months post DMF initiation, respectively, were: non-black/non-AA patients, 0.83 (95% CI 0.80-0.85) versus 0.10 (95% CI 0.09-0.10), 88% lower ARR (P < 0.0001); black/AA patients, 0.68 (95% CI 0.58-0.80) versus 0.07 (95% CI 0.05-0.10), 90% lower ARR (P < 0.0001). In total, 35 (19%) black/AA patients reported adverse events leading to treatment discontinuation; gastrointestinal disorders were most common (7%), consistent with non-black/non-AA patients (8%). Median lymphocyte counts decreased by 22% in the first year (vs 36% in non-black/non-AA patients), then remained stable and above lower limit of normal in most patients.

CONCLUSIONS

Relapse rates remained low in black/AA patients, consistent with non-black/non-AA patients. The safety profile of DMF in black/AA patients was consistent with that in the non-black/non-AA ESTEEM population, although lymphocyte decrease was less pronounced in black/AA patients.

Multiple Sclerosis in a Multi-Ethnic Population in Houston, Texas: A Retrospective Analysis

Multiple Sclerosis (MS) is a progressive neurodegenerative disease that affects more than 2 million people worldwide. Increasing knowledge about MS in different populations has advanced our understanding of disease epidemiology and variation in the natural history of MS among White and minority populations. In addition to differences in incidence, African American (AA) and Hispanic patients have greater disease burden and disability in earlier stages of disease compared to White patients. To further characterize MS in AA and Hispanic populations, we conducted a retrospective chart analysis of 112 patients treated at an MS center in Houston, Texas. Here, we describe similarities and differences in clinical presentation, MRI findings, treatment regimens, disability progression, and relapse rate. While we found several similarities between the groups regarding mean age, disability severity, and degree of brain atrophy at diagnosis, we also describe a few divergences. Interestingly, we found that patients who were evaluated by a neurologist at symptom onset had significantly decreased odds of greater disability [defined as Expanded Disability Status Scale (EDSS) > 4.5] at last presentation compared to patients who were not evaluated by a neurologist (OR: 0.04, 95% CI: 0.16–0.9). We also found that active smokers had significantly increased odds of greater disability both at diagnosis and at last clinical encounter compared to nonsmokers (OR: 2.44, 95% CI: 1.10–7.10, OR= 2.44, 95% CI: 1.35–6.12, p = 0.01, respectively). Additionally, we observed significant differences in treatment adherence between groups. Assessment of the degree of brain atrophy and progression over time, along with an enumeration of T1, T2, and gadolinium-enhancing brain lesions, did not reveal differences across groups.

African Americans experience disproportionate neurodegenerative changes in the medulla and upper cervical spinal cord in early multiple sclerosis

OBJECTIVE

To compare the temporal changes in the 3-dimensional (3D) structure of the medulla-upper cervical spinal cord region in African American (AA) and white multiple sclerosis (MS) patients to identify early patterns of anatomical change prior to progressive symptom development.

METHODS

Standardized 3-Tesla 3D brain MRI studies were performed at two time points on AA and white MS patients along with controls. Longitudinal changes in volume, surface area, tissue compliance, and surface texture measured in total and within ventral and dorsal compartments were studied. Independent regression models were constructed to evaluate differences between groups.

RESULTS

Thirty-five individuals were studied, 10 AA with MS (female (F): 8; median age [IQR]=33.8 years (y) [10.9], median disease duration: 11.8y [11.3]), 20 white MS patients (F: 10; 35.6y [17.4], 7.23y [8.83], and 5 controls (F: 2, 51.8y [10.2]). Expanded Disability Status Scale scores were 0.0 at baseline and at the second MRI time point. Within the medulla-upper cervical spinal cord, AA versus white MS patients exhibited greater rates of atrophy in total (p<0.0001) and within the ventral (p<0.0001) and dorsal (p<0.0001) compartments, reduced surface area (p<0.0001), and reduced tissue compliance in the ventral (p=0.002) and dorsal (p=0.0005) compartments. The rate of change at the dorsal surface, but not the ventral surface, between MRI time points was also greater in AA relative to white MS patients (p<0.0001).

CONCLUSION

Structural changes in distinct anatomical regions of the medulla-upper cervical spinal cord may be reflective of early and disproportionate neurodegeneration in AA MS as compared to whites.

Feasibility of "Sit Less, Move More": An intervention for reducing sedentary behavior Among African Americans with MS

BACKGROUND

Sedentary behavior is a major concern in multiple sclerosis, as it may accelerate disease progression and physical disability. This is especially concerning in African Americans, who present with greater neurological disability than Caucasians.

OBJECTIVE

We conducted a feasibility trial on an intervention targeting sedentary behavior in African Americans with multiple sclerosis.

METHODS

We examined the feasibility of the Sit Less, Move More program, a 12-week behavioral intervention that used text messaging along with theory-driven newsletters and behavioral coaching for managing sedentary behavior. We recruited ambulatory, inactive, African Americans with multiple sclerosis, and assessed feasibility on process, resource, management, and scientific outcomes.

RESULTS

Of the 64 people initially contacted, 45 were assessed for eligibility, 31 were sent the informed consent document, and 30 returned a signed document and were included in the study. Study costs were US$7242.38. Personnel time to complete the study was 130 h. There was a small effect on both device-measured (d = -0.19) and self-reported (d = -0.39) sedentary behavior.

CONCLUSIONS

The Sit Less, Move More intervention is safe and feasible for African Americans with multiple sclerosis, and yielded a small reduction in sedentary behavior. The intervention was low cost and well received. Our results suggest the Sit Less, Move More program should progress towards a Phase II trial to determine its efficacy.

Long-term MS secondary progression: Derivation and validation of a clinical risk score

OBJECTIVE

The risk of progression of multiple sclerosis (MS) related to the association of prognostic factors present at disease onset has rarely been explored. We aimed to construct a clinical risk score for MS long-term progression that could be easily applied in clinical practice.

PATIENTS AND METHODS

Among 432 patients with MS, 288 patients were selected as a derivation sample for identification of the knowledge prognostic factors more associated with long-term progression. One point was given to each risk factor identified as statistically significant by the adjusted model, and the sum of the points gave the overall risk score. Subsequently the score was applied to the remaining 144 patients to confirm if those with higher scores had reached MS secondary progression.

RESULTS

The prognostic factors identified as independently associated with long-term progression were: no specific MS treatment before EDSS 3, age of onset older than 30 years, pyramidal and cerebellar impairment as the first manifestation of disease, time interval between the first and second relapses less than 2 years, and African ancestry. There was no significant difference between expected and observed number of patients in progression (44 vs. 31, p = 0.966), indicating that the score was able to predict the progression in the validation sample. There was no significant difference between patients with low risk (≤ 2 points) (p = 0.98) and high risk (≥ 3 points) (p = 0.48) in the derivation versus validation samples. In the derivation sample, the patients with three or more points had a 2.8-fold increased risk of progression [hazard ratio (HR): 2.8; 95 % confidence interval (CI): 1.2-6.3; p = 0.014).

CONCLUSION

The score proposed was capable of predicting long-term MS progression.

Efficacy and Safety of Alemtuzumab in Patients of African Descent with Relapsing-Remitting Multiple Sclerosis: 8-Year Follow-up of CARE-MS I and II (TOPAZ Study)

INTRODUCTION

Multiple sclerosis (MS) patients of African descent have increased risk for disease progression and may be less responsive to disease-modifying therapy.

METHODS

Patients in the CARE-MS studies received alemtuzumab 12 mg/day [initial alemtuzumab treatment (IAT); baseline: 5 days; 12 months later: 3 days] or subcutaneous interferon beta-1a (SC IFNB-1a) 3 ×/week. Core study outcomes were compared between treatment groups. In the extension study CAMMS03409, SC IFNB-1a-treated patients switched to alemtuzumab [delayed alemtuzumab treatment (DAT)]. Data from IAT and DAT arms were pooled to assess outcomes through 6 years post alemtuzumab initiation; IAT patients had an additional 2 years of follow-up in TOPAZ.

RESULTS

Of 1200 CARE-MS patients, 43 (4%) were of African descent (35 IAT; 8 DAT) and received alemtuzumab in the 2-year core and/or 6-year extension; 29 (67%) remained on study at the time of analysis (24 IAT patients completed year 8 post alemtuzumab; 5 DAT patients completed year 6 post alemtuzumab). In year 2, annualized relapse rate (ARR; 0.09 versus 0.42), percentage of patients with improved Expanded Disability Status Scale (EDSS; 18% versus 11%), 6-month confirmed disability improvement (CDI; 28% versus 13%), no evidence of disease activity (55% versus 13%), and cumulative brain volume loss (BVL; - 0.55% versus - 1.32%) favored alemtuzumab versus SC IFNB-1a. Alemtuzumab remained efficacious at year 6 (pooled IAT/DAT) and at year 8 (IAT only) post alemtuzumab (ARR: 0.15 and 0.30; improved EDSS: 17% and 25%; CDI: 47% and 55%; BVL: - 1.14% and - 0.70%, respectively). No safety signals were unique to this population.

CONCLUSIONS

Alemtuzumab was efficacious in a small cohort of relapsing-remitting MS patients of African descent over 8 years. Safety was consistent with the overall CARE-MS population, although the small sample size may have prevented the detection of known low-frequency adverse events. CLINICALTRIALS.

GOV REGISTRATION NUMBERS

CARE-MS I, II, extension, TOPAZ: NCT00530348, NCT00548405, NCT00930553, NCT02255656.

FUNDING

Sanofi (Cambridge, MA, USA) and Bayer HealthCare Pharmaceuticals (Leverkusen, Germany).

Clinical Characteristics of Multiple Sclerosis in African-Americans

PURPOSE OF REVIEW

Multiple sclerosis (MS) is an autoimmune disease of the central nervous system that affects nearly 1 million people in the USA and has the potential to profoundly affect physical ability and income potential at a young age. Since a landmark paper was published in 2014, few studies have looked at differences in MS disease characteristics between African-American and Caucasian patients.

RECENT FINDINGS

African-American patients often have a more severe MS disease course, as well as biomarker data which can portend a worse prognosis. While the sample sizes are usually quite small, subgroup analyses of African-American patients have been performed to evaluate efficacy of disease-modifying treatments as compared with the entire study population, made up of primarily Caucasians. In an era where we strive for personalized medicine, understanding racial differences in MS may help us better treat African-American patients in the future.

Muscle Dysfunction and Walking Impairment in Women with Multiple Sclerosis

Background

Recent evidence suggests that skeletal muscle dysfunction is involved in disability progression in people with multiple sclerosis (MS). However, the relationship between muscle dysfunction and walking impairments in MS remains unclear. Thus, the cross-sectional relationships between muscle-specific oxidative capacity and walking endurance in women with MS were evaluated.

Methods

Twenty women with MS (11 African American, 9 white) were tested. Muscle oxidative capacity of the medial gastrocnemius was measured using near-infrared spectroscopy after electrical stimulation. Muscle endurance was evaluated using accelerometer-based mechanomyography during electrical stimulation. Muscle strength was measured during maximal voluntary plantarflexion using handheld dynamometry. Walking function was measured using the Timed 25-Foot Walk test and the 6-Minute Walk Test (6MWT).

Results

Reduced muscle oxidative capacity (R ² = 0.68-0.71, P < .01) and muscle endurance (R ² = 0.59-0.78, P < .01) were associated with lower Timed 25-Foot Walk time and 6MWT distance. Muscle strength was weakly correlated to 6MWT distance (R ² = 0.21, P = .02). No differences in muscle function or clinical outcome measures were found between African American and white subgroups. Women with moderate-to-severe disability (Expanded Disability Status Scale [EDSS] score, 5.0-6.5) had significantly reduced muscle oxidative capacity, muscle endurance, and walking ability compared with women with mild disability (EDSS score, 2.5-4.5).

Conclusions

Reductions in muscle function in people with MS are related to declines in walking function across all levels of disability. Muscle dysfunction is not differentially related to walking impairment in African American and white women with MS.

Optical coherence tomography and multiple sclerosis: Update on clinical application and role in clinical trials

Optical coherence tomography (OCT) has emerged as a fast, non-invasive, inexpensive, high-resolution imaging technique in multiple sclerosis (MS). Retinal layer quantification by OCT facilitates a 'window' into not only local retinal pathology but also global neurodegenerative processes, recognised to be the principal substrates of disability accumulation in MS. While OCT measures in MS have been demonstrated to reflect visual function, inflammatory activity outside of the visual pathways, disability measures including the prediction of disability progression, whole brain atrophy, and the differential neuroprotective effects of disease-modifying therapies, debate continues regarding the clinical utility of OCT in everyday practice. This review presents an overview of the evidence supporting OCT, with particular focus on its application in the MS clinic. We will also discuss the role of OCT in MS clinical trials to develop novel neuroprotective and potential remyelinating therapies.

Brain and retinal atrophy in African-Americans versus Caucasian-Americans with multiple sclerosis: a longitudinal study

On average, African Americans with multiple sclerosis demonstrate higher inflammatory disease activity, faster disability accumulation, greater visual dysfunction, more pronounced brain tissue damage and higher lesion volume loads compared to Caucasian Americans with multiple sclerosis. Neurodegeneration is an important component of multiple sclerosis, which in part accounts for the clinical heterogeneity of the disease. Brain atrophy appears to be widespread, although it is becoming increasingly recognized that regional substructure atrophy may be of greater clinical relevance. Patient race (within the limitations of self-identified ancestry) is regarded as an important contributing factor. However, there is a paucity of studies examining differences in neurodegeneration and brain substructure volumes over time in African Americans relative to Caucasian American patients. Optical coherence tomography is a non-invasive and reliable tool for measuring structural retinal changes. Recent studies support its utility for tracking neurodegeneration and disease progression in vivo in multiple sclerosis. Relative to Caucasian Americans, African American patients have been found to have greater retinal structural injury in the inner retinal layers. Increased thickness of the inner nuclear layer and the presence of microcystoid macular pathology at baseline predict clinical and radiological inflammatory activity, although whether race plays a role in these changes has not been investigated. Similarly, assessment of outer retinal changes according to race in multiple sclerosis remains incompletely characterized. Twenty-two African Americans and 60 matched Caucasian Americans with multiple sclerosis were evaluated with brain MRI, and 116 African Americans and 116 matched Caucasian Americans with multiple sclerosis were monitored with optical coherence tomography over a mean duration of 4.5 years. Mixed-effects linear regression models were used in statistical analyses. Grey matter (-0.9%/year versus -0.5%: P =0.02), white matter (-0.7%/year versus -0.3%: P =0.04) and nuclear thalamic (-1.5%/year versus -0.7%/year: P =0.02) atrophy rates were approximately twice as fast in African Americans. African Americans also exhibited higher proportions of microcystoid macular pathology (12.1% versus 0.9%, P =0.001). Retinal nerve fibre layer (-1.1% versus -0.8%: P =0.02) and ganglion cell+ inner plexiform layer (-0.7%/year versus -0.4%/year: P =0.01) atrophy rates were faster in African versus Caucasian Americans. African Americans on average exhibited more rapid neurodegeneration than Caucasian Americans and had significantly faster brain and retinal tissue loss. These results corroborate the more rapid clinical progression reported to occur, in general, in African Americans with multiple sclerosis and support the need for future studies involving African Americans in order to identify individual differences in treatment responses in multiple sclerosis.

An MRI evaluation of grey matter damage in African Americans with MS

OBJECTIVE

Multiple sclerosis (MS) is less prevalent in African Americans (AAs) than Caucasians (CAs) but in the former the disease course tends to be more severe. In order to clarify the MRI correlates of disease severity in AAs, we performed a multimodal brain MRI study to comprehensively assess the extent of grey matter (GM) damage and the degree of functional adaptation to structural damage in AAs with MS.

METHODS

In this cross-sectional study, we characterized GM damage in terms of focal lesions and volume loss and functional adaptation during the execution of a simple motor task on a sample of 20 AAs and 20 CAs with MS and 20 healthy controls (CTRLs).

RESULTS

In AAs, we observed a wider range of EDSS scores than CAs, with multisystem involvement being more likely in AAs (p < 0.01). While no significant differences were detected in lesion loads and global brain volumes, AAs showed regional atrophy in the posterior lobules of cerebellum, temporo-occipital and frontal regions in comparison with CAs (p < 0.01), with cerebellar atrophy being the best metric in differentiating AAs from CAs (p = 0.007, AUC = 0.96 and p = 0.005, AUC = 0.96, respectively for right and left cerebellar clusters). In AAs, the functional analysis of cortical activations showed an increase in task-related activation of areas involved in high level processing and a decreased activation in the medial prefrontal cortex compared to CAs.

INTERPRETATION

In our study, the direct comparison of AAs and CAs points to cerebellar atrophy as the main difference between subgroups.

Multiple sclerosis: long-term outcomes in ethnic minorities. Analysis of a UK population-based registry

BACKGROUND AND PURPOSE

Multiple sclerosis (MS) is most frequent in Caucasian populations. However, studies of MS in other ethnic groups may offer unique insights into genetic and environmental influences on the disease, and data on long-term outcomes in these patients is limited. In this work clinical features and time to disability milestones were investigated in ethnic minority (EM) patients with MS in a UK population and comparisons were made to a Caucasian cohort from the same region.

METHODS

In all, 1949 MS patients (1866 Caucasian, 83 EM) were identified from a regional disease registry. Cox proportional hazards regression was used to analyse the time to Expanded Disability Status Scale (EDSS) 3.0, 4.0 and 6.0.

RESULTS

Ethnic minority patients were younger at disease onset (28.6 years vs. 32.8 years, P = 0.001), and primary progressive MS was less common (EM 4.8%, Caucasian 11.6%, P = 0.03). After correction for clinical variables, ethnicity was associated with time to EDSS 3.0 [EM: hazard ratio (HR) 1.75, P < 0.0001] and 4.0 (HR 1.46, P = 0.03), but not 6.0 (HR 1.5, P = 0.05).

CONCLUSIONS

Ethnic minority patients reach early levels of fixed disability more rapidly than Caucasian patients, but this effect diminishes at later stages of the disease. This has implications for clinical management of these patients.

Pediatric Multiple Sclerosis: Genes, Environment, and a Comprehensive Therapeutic Approach

BACKGROUND

Pediatric multiple sclerosis is an increasingly recognized and studied disorder that accounts for 3% to 10% of all patients with multiple sclerosis. The risk for pediatric multiple sclerosis is thought to reflect a complex interplay between environmental and genetic risk factors.

MAIN FINDINGS

Environmental exposures, including sunlight (ultraviolet radiation, vitamin D levels), infections (Epstein-Barr virus), passive smoking, and obesity, have been identified as potential risk factors in youth. Genetic predisposition contributes to the risk of multiple sclerosis, and the major histocompatibility complex on chromosome 6 makes the single largest contribution to susceptibility to multiple sclerosis. With the use of large-scale genome-wide association studies, other non-major histocompatibility complex alleles have been identified as independent risk factors for the disease. The bridge between environment and genes likely lies in the study of epigenetic processes, which are environmentally-influenced mechanisms through which gene expression may be modified.

CONCLUSIONS

This article will review these topics to provide a framework for discussion of a comprehensive approach to counseling and ultimately treating the pediatric patient with multiple sclerosis.

Application of the McDonald criteria in Latin America

The diagnosis of multiple sclerosis (MS) is based on neurological symptoms and signs, alongside evidence of dissemination of central nervous system (CNS) lesions in space and time. In the absence of a sensitive and specific diagnostic test, diagnostic criteria are needed for diagnosing MS. The caveat to the application of the McDonald criteria is that alternative diagnoses must be excluded. The prevalence, clinical phenotype and the differential diagnosis of MS may have variations in different populations, especially in Latin America (LATAM). Considering that MS diagnostic criteria were developed with data gathered largely from adult Caucasian European and North American populations, their applicability and accuracy in ethnical/genetic diverse populations may be affected. There are scarce data in our region about the reliability of MS criteria.

Hispanic Americans and African Americans with multiple sclerosis have more severe disease course than Caucasian Americans

Whether disease course in Hispanic Americans (HA) with multiple sclerosis (MS) is different from Caucasian Americans (CA) or African Americans (AA) is unknown. We compared MS severity in the three main ethnic populations in our tertiary MS clinics using disease duration–adjusted rank score of disability: Patient-Derived Multiple Sclerosis Severity Score (P-MSSS). The age- and gender-adjusted P-MSSS was significantly higher in HA (3.9 ± 2.6) and AA (4.5 ± 3.0) compared to CA (3.4 ± 2.6; p < 0.0001 for both). Adjusting for insurance did not change these results. These findings suggest that HA, as AA, have more rapid disability accumulation than CA.

Disability and progression in Afro-descendant patients with multiple sclerosis

ABSTRACT Multiple sclerosis (MS) prevalence is higher in Caucasian (CA) populations, narrowing the analysis of the impact of Afro-descendant (AD) populations in disease outcomes. Even so, recent studies observed that AD patients have a more severe course. The main objective of this study is to confirm and discuss, through a systematic review, that being AD is a risk factor for disability accumulation and/or severe progression in patients with MS. A systematic review of published data in the last eleven years was performed, which evaluated clinical aspects and long term disability in patients with MS. Fourteen studies were included. Of these fourteen articles, thirteen observed a relationship between ancestry and poorer outcome of MS. African ancestry is a condition inherent in the patient and should be considered as an initial clinical characteristic affecting prognosis, and influencing which therapeutic decision to make in initial phases.

Differential Impact of Multiple Sclerosis on Cortical and Deep Gray Matter Structures in African Americans and Caucasian Americans

BACKGROUND

African Americans with multiple sclerosis (AAwMS) have different disease phenotypes when compared to Caucasians Americans with MS (CAwMS). The pathologic basis of this difference in disease presentation is unknown.

METHODS

Fifty-Four AAwMS and 54 CAwMS were appropriately matched for age, gender, treatment duration, and disease duration. FreeSurfer was used to segment brain white matter and gray matter from T1 images and compute thalamic volume. Regional cortical thickness was calculated using QDEC.

RESULTS

The 2 matched cohorts differed in disability, with AAwMS demonstrating significantly higher EDSS scores (2.3±2.2 vs. 1.3±1.5, P < .009), yet the 2 populations had similar T2 hyperintense lesion volumes (P = .35). AAwMS had a significantly lower total global cortical thickness when compared to CAwMS (P = .03). Controlling for EDSS, AAwMS showed multiple cortical regions to be significantly thinner than CAwMS; these included areas within the temporal, parietal and occipital lobes, as well as the precentral and postcentral gyrus. Middletemporal cortex was most affected in AAwMS in the left hemisphere (P = .009), while the superiortemporal cortex was most affected in the right hemisphere (P = .0001). In contrast, thalamic volume was significantly reduced in CAwMS when compared to AAwMS (P = .01). In both groups, worse disability was associated with lower total thalamic volume percentage.

CONCLUSION

AAwMS and CAwMS patients differ with regard to global and regional cortical thickness and thalamic volume. This diverging pattern of gray matter volumetrics among otherwise matched patients suggests that racial-specific disease differences may exist.