A comparison of brain magnetic resonance imaging lesions in multiple sclerosis by race with reference to disability progression

Imaging phenotypic differences in multiple sclerosis: at the crossroads of aging, sex, race, and ethnicity

Clear sex differences are observed in clinical and imaging phenotypes of multiple sclerosis (MS), which evolve significantly over the age spectrum, and more specifically, during reproductive milestones such as pregnancy and menopause. With neuroimaging being an outcome measure and also a key subclinical biomarker of subsequent clinical phenotype in MS, this comprehensive review aims to provide an overview of sex and hormone differences in structural and functional imaging biomarkers of MS, including lesion burden and location, atrophy, white matter integrity, functional connectivity, and iron distribution. Furthermore, how therapies aimed at altering sex hormones can impact imaging of women and men with MS over the lifespan is discussed. This review also explores the key intersection between age, sex, and race/ethnicity in MS, and how this intersection may affect imaging biomarkers of MS.

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.

Do magnetic resonance imaging features differ between persons with multiple sclerosis of various races and ethnicities?

Those of African American or Latin American descent have been demonstrated to have more severe clinical presentations of multiple sclerosis (MS) than non-Latin American White people with MS. Concurrently, radiological burden of disease on magnetic resonance imaging (MRI) in African Americans with MS has also been described as being more aggressive. Here, we review MRI studies in diverse racial and ethnic groups (adult and pediatric) investigating lesion burden, inflammation, neurodegeneration, and imaging response to disease modifying therapy. We also discuss why such disparities may exist beyond biology, and how future studies may provide greater insights into underlying differences.

Understanding humoral immunity and multiple sclerosis severity in Black, and Latinx patients

People identified with Black/African American or Hispanic/Latinx ethnicity are more likely to exhibit a more severe multiple sclerosis disease course relative to those who identify as White. While social determinants of health account for some of this discordant severity, investigation into contributing immunobiology remains sparse. The limited immunologic data stands in stark contrast to the volume of clinical studies describing ethnicity-associated discordant presentation, and to advancement made in our understanding of MS immunopathogenesis over the past several decades. In this perspective, we posit that humoral immune responses offer a promising avenue to better understand underpinnings of discordant MS severity among Black/African American, and Hispanic/Latinx-identifying patients.

Towards imaging criteria that best differentiate MS from NMOSD and MOGAD: Large multi-ethnic population and different clinical scenarios

BACKGROUND

The "1/3″ brain magnetic resonance imaging (MRI) criteria including 1) a lesion adjacent to the lateral ventricle and in the inferior temporal lobe, or 2) a juxtacortical lesion, or 3) a Dawson finger-type lesion were shown to distinguish multiple sclerosis (MS) from antibody-mediated conditions. In this large multicentre study, we aimed to assess how the criteria perform 1) in different onset phenotypes, 2) distinct ethnic groups, 3) when the absence of myelin oligodendrocyte glycoprotein antibody (MOG-Ab)-associated disease (MOGAD)-typical fluffy infratentorial (FIT) lesions and longitudinally extensive transverse myelitis (LETM) lesions are added as features ("2/4″ and 3/5″ criteria, respectively).

METHODS

577 patients with MS (n = 332), aquaporin-4 antibody (AQP4-Ab) neuromyelitis optica spectrum disorder (NMOSD) (n = 196) and MOGAD (n = 49) were recruited from 6 international centres (Buenos Aires, Sao Paolo, Maracaibo, Goyang, Oxford and Milan). Imaging scans were obtained at disease onset or relapse.

RESULTS

Adding the absence of FIT lesions increased the specificity of the "1/3″ criteria vs. AQP4-Ab NMOSD from 84.7% to 87.2% and vs. MOGAD from 85.7% to 93.9% without compromising their sensitivity (86%). In particular, for those presenting with brain/brainstem attacks "2/4″ had significantly higher specificity than "1/3″ (85% vs. 80% against AQP4-Ab NMOSD, 88.9% vs. 72.2% against MOGAD). Positive predictive values of the "1/3″ criteria for MS were lowest for Asian patients (84.8 vs. 99.1% for White) but were significantly increased by adding further criteria (94.1% for "3/5″).

CONCLUSION

The "1/3″ criteria perform well in discriminating MS from NMOSD and MOGAD regardless of ethnic background and clinical scenario. Adding the absence of FIT lesions increases the specificity in those presenting with brain/brainstem symptoms.

Automated quantification of deep grey matter structures and white matter lesions using magnetic resonance imaging in relapsing remission multiple sclerosis

Background

Brain volume loss (BVL) is widespread in MS and occurs throughout the disease course at a rate considerably greater than in the general population. In MS, brain volume correlates with and predicts future disability, making BVL a relevant measure of diffuse CNS damage leading to clinical disease progression, as well as serving as a useful outcome in evaluating MS therapies. The aim of our study was to evaluate the role of automated segmentation and quantification of deep grey matter structures and white matter lesions in Relapsing Remitting Multiple Sclerosis patients using MR images and to correlate the volumetric results with different degrees of disability based on expanded disability status scale (EDSS) scores.

Results

All the patients in our study showed relative atrophy of the thalamus and the putamen bilaterally when compared with the normal control group. Statistical analysis was significant for the thalamus and the putamen atrophy (P value < 0.05). On the other hand, statistical analysis was not significant for the caudate and the hippocampus (P value > 0.05); there was a significant positive correlation between the white matter lesions volume and EDSS scores (correlation coefficient of 0.7505). On the other hand, there was a significant negative correlation between the thalamus and putamen volumes, and EDSS scores (correlation coefficients < − 0.9), while the volumes of the caudate and the hippocampus had a very weak and non-significant correlation with the EDSS scores (correlation coefficients > − 0.35).

Conclusions

The automated segmentation and quantification tools have a great role in the assessment of brain structural changes in RRMS patients, and that it became essential to integrate these tools in the daily medical practice for the great value they add to the current evaluation measures.

The effects of copper sulfate on the structure and function of the rat cerebellum: A stereological and behavioral study

Copper (Cu) is a vital trace element that acts as a cofactor of proteins and enzymes in many molecular pathways including the central nervous system. The accumulation or deficiency of copper could alter neuronal function and lead to neuronal degeneration and brain dysfunction. Intake of high levels of copper can also cause copper toxicosis that affects the brain structure and function. Despite clinical and experimental data indicating the association between abnormal copper homeostasis and brain dysfunction, the effects of copper on cerebellum have remained poorly understood. Hence, this study aimed to evaluate the effects of copper sulfate on the cerebellum via stereological and behavioral methods in rats. Male rats (Sprague-Dawley) were divided to three groups. The rats in the control group orally received distilled water, while those in the Cu groups received 1 mM (159 mg/L) or 8 mM (1272 mg/L) copper sulfate by oral gavage solved in distilled water daily for 4 weeks. Then, the rotarod performance test was recorded and the cerebellum was prepared for stereological assessments. The Cu-administered rats (1 and 8 mM) exhibited a significant reduction in the total volumes of the cerebellum structures. The total number of the cells in the cerebellar cortex and deep cerebellar nuclei were significantly decreased via Cu in a dose-dependent manner. Furthermore, the length of nerve fibers and the number of spines per nerve fiber decreased significantly in the Cu groups. These changes were correlated to the animals' motor performance impairment in the rotarod test. The findings suggested that copper toxicity induced motor performance impairments in the rats, which could be attributed to its deleterious effects on the cerebellum structure.

HLA genotype-clinical phenotype correlations in multiple sclerosis and neuromyelitis optica spectrum disorders based on Japan MS/NMOSD Biobank data

HLA genotype-clinical phenotype correlations are not established for multiple sclerosis (MS) and neuromyelitis optica spectrum disorders (NMOSD). We studied HLA-DRB1/DPB1 genotype–phenotype correlations in 528 MS and 165 NMOSD cases using Japan MS/NMOSD Biobank materials. HLA-DRB1*04:05, DRB1*15:01 and DPB1*03:01 correlated with MS susceptibility and DRB1*01:01, DRB1*09:01, DRB1*13:02 and DPB1*04:01 were protective against MS. HLA-DRB1*15:01 was associated with increased optic neuritis and cerebellar involvement and worsened visual and pyramidal functional scale (FS) scores, resulting in higher progression index values. HLA-DRB1*04:05 was associated with younger onset age, high visual FS scores, and a high tendency to develop optic neuritis. HLA-DPB1*03:01 increased brainstem and cerebellar FS scores. By contrast, HLA-DRB1*01:01 decreased spinal cord involvement and sensory FS scores, HLA-DRB1*09:01 decreased annualized relapse rate, brainstem involvement and bowel and bladder FS scores, and HLA-DRB1*13:02 decreased spinal cord and brainstem involvement. In NMOSD, HLA-DRB1*08:02 and DPB1*05:01 were associated with susceptibility and DRB1*09:01 was protective. Multivariable analysis revealed old onset age, long disease duration, and many relapses as independent disability risks in both MS and NMOSD, and HLA-DRB1*15:01 as an independent risk only in MS. Therefore, both susceptibility and protective alleles can influence the clinical manifestations in MS, while such genotype–phenotype correlations are unclear in NMOSD.

Assessment of Racial/Ethnic Disparities in Volumetric MRI Correlates of Clinical Disability in Multiple Sclerosis: A Preliminary Study

BACKGROUND AND PURPOSE

Although global and regional brain volume has been established as a relevant measure to define and predict multiple sclerosis (MS) severity, characterization of specific trends by race/ethnicity is currently lacking. We aim to (1) characterize racial disparities in disability-specific patterns of brain MRI volumetric measures between Hispanic and Caucasian individuals with MS and (2) explore the relevance of these measures as predictors of clinical disability progression.

METHODS

Brain MRI scans from 94 Hispanic and 94 age- and gender-matched Caucasian MS patients were analyzed using automatic and manual segmentation techniques. Select global and regional volume measures were correlated to Expanded Disability Status Scale (EDSS) scores at baseline and subsequent follow-up visits.

RESULTS

Hispanic patients had a higher baseline median EDSS score (interquartile range [IQR], 2.0; [1.0-3.5]) compared to Caucasians (median [IQR], 1.0 [.0-2.0]) and an increased risk of requiring ambulatory assistance (hazard ratio [HR], 9.7; 95% confidence interval [CI], 2.8-32.5). Normalized thalamic volume was moderately associated with EDSS scores (r_s   = -.42,  P < .001 in Hispanics; r_s   = -.32, P  = .002 in Caucasians) and was the best predictor of sustained disability worsening in both racial groups in a time-to-event analysis.

CONCLUSIONS

The confounding impact of race on quantitative brain volume measures may affect the interpretation of outcome measures in MS clinical trials.

IgG Index Revisited: Diagnostic Utility and Prognostic Value in Multiple Sclerosis

Objective: Early and accurate diagnosis of multiple sclerosis (MS) remains a clinical challenge. The main objective is to evaluate the diagnostic and prognostic value of the routinely performed immunoglobulin G (IgG) index for MS patients in the Asian population.

Methods: A retrospective study was conducted among a cohort of clinically isolated syndrome (CIS) patients in China with known oligoclonal band (OCB) status and IgG index at baseline. We first evaluated the predictive value of IgG index for OCB status. Secondly, the diagnostic utility and prognostic value of IgG index alone were tested. Lastly, we incorporated IgG index into the 2017 McDonald criteria by replacing OCB with either “IgG index or OCB” (modified criteria 1), “IgG index and OCB” (modified criteria 2), or “IgG index” (modified criteria 3). The diagnostic utility of different criteria was calculated and compared.

Results: In a CIS cohort in China (n = 105), IgG index > 0.7 forecasted OCB positivity (X² = 22.90, P < 0.001). An elevated IgG index was highly prognostic of more clinical relapses [1-year adjusted odds ratio [OR] = 1.32, P = 0.015; 2-years adjusted OR = 1.69, P = 0.013] and Expanded Disability Status Scale worsening (1-year adjusted OR = 1.76, P = 0.040; 2-years adjusted OR = 1.85, P = 0.032). Under the 2017 McDonald criteria (Positive Likelihood Ratio = 1.54, Negative Likelihood Ratio = 0.56), an IgG index > 0.7 in CIS patients increased the likelihood of developing MS within 2 years, either when OCB status was unknown (Positive Likelihood Ratio = 2.11) or with OCB positivity (Positive Likelihood Ratio = 2.11) at baseline; An IgG index ≤ 0.7, along with a negative OCB, helped rule out the MS diagnosis (Negative Likelihood Ratio = 0.53).

Conclusions: IgG index > 0.7 predicts OCB positivity at the initial attack of MS and is prognostic of early disease activity. IgG index serves as an easily-obtainable and accurate OCB surrogate for MS diagnosis in the Asian population.

Two susceptible HLA-DRB1 alleles for multiple sclerosis differentially regulate anti-JC virus antibody serostatus along with fingolimod

Background

Progressive multifocal leukoencephalopathy (PML) caused by JC virus (JCV) is a rare but serious complication of some disease-modifying drugs used to treat multiple sclerosis (MS). Japanese MS patients treated with fingolimod were reported to be 10 times more likely to develop PML than equivalent patients in other countries. The strongest susceptibility human leukocyte antigen (HLA) class II alleles for MS are distinct between races (DRB1*15:01 for Caucasians and DRB1*04:05 and DRB1*15:01 for Japanese); therefore, we investigated whether HLA class II alleles modulate anti-JCV antibody serostatus in Japanese MS patients with and without fingolimod.

Methods

We enrolled 128 Japanese patients with MS, in whom 64 (50%) were under fingolimod treatment at sampling, and examined the relationship between HLA class II alleles and anti-JCV antibody serostatus. Serum anti-JCV antibody positivity and index were measured using a second-generation two-step assay and HLA-DRB1 and -DPB1 alleles were genotyped.

Results

HLA-DRB1*15 carriers had a lower frequency of anti-JCV antibody positivity (57% vs 78%, p = 0.015), and lower antibody index (median 0.42 vs 1.97, p = 0.037) than non-carriers. Among patients without HLA-DRB1*15, DRB1*04 carriers had a higher seropositivity rate than non-carriers (84% vs 54%, p = 0.030), and DPB1*04:02 carriers had a higher anti-JCV antibody index than non-carriers (3.20 vs 1.34, p = 0.008) although anti-JCV antibody-positivity rates did not differ. Patients treated with fingolimod had a higher antibody index than other patients (1.46 vs 0.64, p = 0.039) and treatment period had a positive correlation with antibody index (p = 0.018). Multivariate logistic regression analysis revealed that age was positively associated, and HLA-DRB1*15 was negatively associated with anti-JCV antibody positivity (odds ratio [OR] = 1.06, p = 0.006, and OR = 0.37, p = 0.028, respectively). Excluding HLA-DRB1*15-carriers, DRB1*04 was an independent risk factor for the presence of anti-JCV antibody (OR = 5.50, p = 0.023).

Conclusions

HLA-DRB1*15 is associated with low anti-JCV antibody positive rate and low JCV antibody index, and in the absence of DRB1*15, DRB1*04 carriers are associated with a high antibody positive rate in Japanese, suggesting the effects of two susceptible HLA-DRB1 alleles on anti-JCV antibody serostatus differ.

Contribution of cortical lesions to cognitive impairment in Japanese patients with multiple sclerosis

Cortical lesions (CLs) have a low prevalence and are associated with physical disabilities in Japanese patients with multiple sclerosis (MS). However, the contribution of CLs to cognitive impairment remains unclear in Asian MS. Sixty-one prospectively enrolled MS patients underwent three-dimensional double inversion recovery MR imaging, the Brief Repeatable Battery of Neuropsychological Tests (BRB-N), the Apathy Scale (AS), the Fatigue Questionnaire (FQ), and the Hospital Anxiety and Depression Scale (HADS) within a 1-week period. The cognitive impairment index (CII) score was calculated to measure patients’ overall cognitive impairment. MS patients with CLs had poorer scores than those without CLs in most BRB-N tests, but scored comparably in the FQ, AS, and HADS. The number of CLs correlated negatively with all BRB-N test scores and positively with total CII scores. Leukocortical lesions were more extensively associated with cognitive dysfunction in various domains than intracortical lesions. Stepwise multiple regression analysis revealed that potential confounding factors for the highest quartile of CII score were the number of CLs (odds ratio 2.38, p = 0.0070) and the Expanded Disability Severity Scale score (odds ratio 2.13, p = 0.0003). Our results demonstrate that the presence and number of CLs are robustly associated with cognitive dysfunction in Asian MS patients.

Brain volume is related to neurological impairment and to copper overload in Wilson's disease

Introduction

To determine whether brain volume was associated with functional and neurological impairments and with copper overload markers in patients with Wilson’s disease.

Methods

In 48 treatment-naïve patients, we assessed functional and neurological impairments with the Unified Wilson’s Disease Rating Scale, measured normalized brain volumes based on magnetic resonance images, and assessed concentration of non-ceruloplasmin-bound copper. We correlated brain volume measures with functional and neurological impairment scores and copper overload indices.

Results

Functional and neurological impairments correlated with all brain volume measures, including the total brain volume and the volumes of white matter and gray matter (both peripheral gray matter and deep brain nuclei). Higher non-ceruloplasmin-bound copper concentrations were associated with greater functional and neurological impairments and lower brain volumes.

Conclusions

Our findings provided the first in vivo evidence that the severity of brain atrophy is a correlate of functional and neurological impairments in patients with Wilson’s disease and that brain volume could serve as a marker of neurodegeneration induced by copper.

Electronic supplementary material

The online version of this article (10.1007/s10072-019-03942-z) contains supplementary material, which is available to authorized users.