Distinct plasma lipids predict axonal injury and multiple sclerosis activity.

BACKGROUND: Lipids are of particular interest for the study of neuroinjury and neuroinflammation as structural lipids are major components of myelin, and a variety of lipid species modulate inflammation. In this study, we performed an in-depth lipidomics analysis to identify lipids associated with injury and disease activity. METHODS: Plasma samples were collected from paediatric-onset multiple sclerosis (MS) cases within 4 years of disease onset from 17 sites. The lipidome was measured using untargeted and targeted mass spectrometry. For cross-sectional analyses, the agreement between multiple machine learning models was used to predict neurofilament light chain (NfL) levels. In longitudinal analyses, the association between clinical (relapse count) and imaging (MRI count with ≥1 enhancing or new T2 lesion) outcomes with each metabolite was estimated using adjusted negative binomial regression. RESULTS: At sample collection, 68% of the 435 included individuals were treatment-naive, with a median disease duration of 0.8 years (IQR 0.3-1.7). For longitudinal analyses, 381 and 335 subjects had at least 1 year of clinical and imaging follow-up, respectively. In cross-sectional analyses, NfL chain levels identified structural lipids (phosphatidylcholines and phosphatidylethanolamines) as the highest-performing predictors, including external validation. In contrast, longitudinal analyses found polyunsaturated fatty acids (PUFAs) and their derivatives to be protective from subsequent disease activity (q<0.001, multiple outcomes). CONCLUSION: There are two categories of lipids associated with MS processes. First, structural lipids strongly associated with NfL levels may result from cell lysis secondary to acute inflammation. In contrast, PUFAs, especially ω-3, had a protective effect on subsequent disease activity.

Predictors of a relapsing course in myelin oligodendrocyte glycoprotein antibody-associated disease.

BACKGROUND: Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is a recently described demyelinating disorder, and children represent about 50% of all cases. Almost half of the patients experience relapses, but very few studies have evaluated predictors of relapse risk, challenging clinical management. The study aimed to identify predictors at MOGAD onset that are associated with a relapsing course. METHODS: Prospectively collected data from paediatric patients with MOGAD seen by the US Network of Paediatric MS Centres were leveraged. Univariable and adjusted multivariable models were used to predict recurrent disease. RESULTS: We identified 326 MOGAD cases (mean age at first event 8.9 years [SD 4.3], 57% female, 77% white and 74% non-Hispanic) and 46% relapsed during a mean follow-up of 3.9 years (SD 4.1). In the adjusted multivariable model, female sex (HR 1.66, 95% CI 1.17 to 2.36, p=0.004) and Hispanic/Latino ethnicity (HR 1.77, 95% CI 1.19 to 2.64, p=0.005) were associated with a higher risk of relapsing MOGAD. Maintenance treatment initiated before a second event with rituximab (HR 0.25, 95% CI 0.07 to 0.92, p=0.037) or intravenous immunoglobulin (IVIG) (HR 0.35, 95% CI 0.14 to 0.88, p=0.026) was associated with lower risk of a second event in multivariable analyses. Conversely, maintenance steroids were associated with a higher estimated relapse risk (HR 1.76, 95% CI 0.90 to 3.45, p=0.097). CONCLUSION: Sex and ethnicity are associated with relapsing MOGAD. Use of rituximab or IVIG therapy shortly after onset is associated with a lower risk of the second event. Preventive treatment after a first event could be considered for those with a higher relapse risk.

Susceptibility-based imaging aids accurate distinction of pediatric-onset MS from myelin oligodendrocyte glycoprotein antibody-associated disease.

BACKGROUND: Myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) and pediatric-onset multiple sclerosis (POMS) share clinical and magnetic resonance imaging (MRI) features but differ in prognosis and management. Early POMS diagnosis is essential to avoid disability accumulation. Central vein sign (CVS), paramagnetic rim lesions (PRLs), and central core lesions (CCLs) are susceptibility-based imaging (SbI)-related signs understudied in pediatric populations that may help discerning POMS from MOGAD. METHODS: T2-FLAIR and SbI (three-dimensional echoplanar imaging (3D-EPI)/susceptibility-weighted imaging (SWI) or similar) were acquired on 1.5T/3T scanners. Two readers assessed CVS-positive rate (%CVS+), and their average score was used to build a receiver operator curve (ROC) assessing the ability to discriminate disease type. PRLs and CCLs were identified using a consensual approach. RESULTS: The %CVS+ distinguished 26 POMS cases (mean age 13.7 years, 63% females, median EDSS 1.5) from 14 MOGAD cases (10.8 years, 35% females, EDSS 1.0) with ROC = 1, p < 0.0001, (cutoff 41%). PRLs were only detectable in POMS participants (mean 2.1±2.3, range 1-10), discriminating the two conditions with a sensitivity of 69% and a specificity of 100%. CCLs were more sensitive (81%) but less specific (71.43%). CONCLUSION: The %CVS+ and PRLs are highly specific markers of POMS. After proper validation on larger multicenter cohorts, consideration should be given to including such imaging markers for diagnosing POMS at disease onset.

Smoking and multiple sclerosis risk in black people: A nested case-control study.

BACKGROUND: Smoking is a well-established risk factor for MS; however, it is not known whether its effect on disease risk varies by race/ethnicity. METHODS: We conducted a nested case-control study among US military personnel who have serum samples stored at the Department of Defense Serum Repository. We measured serum cotinine levels, a marker of tobacco smoke exposure, in 157 Black and 23 White individuals who developed MS during follow-up. Controls were randomly selected and matched to each case by age, sex, race/ethnicity, dates of sample collection, and branch of military service. RESULTS: Smoking was not associated with an increased risk of MS in Black people (RR: 1.08, 95 % CI: 0.63-1.85). The results remained similar in analyses restricted to smoking status at baseline, to samples collected 5 years before symptom onset, and using different cut-off levels in cotinine to define smoking status. Smoking was not statistically significantly associated with MS risk in White people, but the point estimate was similar to what has previously been reported in other studies (RR: 1.85, 95 % CI: 0.56-6.16). CONCLUSIONS: Smoking was not associated with MS risk in Black people. Given the consistent association between smoking and MS risk in predominantly White populations, this may suggest that the association between smoking and MS varies by race/ethnicity.

Short-chain fatty acid producers in the gut are associated with pediatric multiple sclerosis onset.

OBJECTIVE: The relationship between multiple sclerosis and the gut microbiome has been supported by animal models in which commensal microbes are required for the development of experimental autoimmune encephalomyelitis. However, observational study findings in humans have only occasionally converged when comparing multiple sclerosis cases and controls which may in part reflect confounding by comorbidities and disease duration. The study of microbiome in pediatric-onset multiple sclerosis offers unique opportunities as it is closer to biological disease onset and minimizes confounding by comorbidities and environmental exposures. METHODS: A multicenter case-control study in which 35 pediatric-onset multiple sclerosis cases were 1:1 matched to healthy controls on age, sex, self-reported race, ethnicity, and recruiting site. Linear mixed effects models, weighted correlation network analyses, and PICRUSt2 were used to identify microbial co-occurrence networks and for predicting functional abundances based on marker gene sequences. RESULTS: Two microbial co-occurrence networks (one reaching significance after adjustment for multiple comparisons; q < 0.2) were identified, suggesting interdependent bacterial taxa that exhibited association with disease status. Both networks indicated a potentially protective effect of higher relative abundance of bacteria observed in these clusters. Functional predictions from the significant network suggested a contribution of short-chain fatty acid producers through anaerobic fermentation pathways in healthy controls. Consistent family-level findings from an independent Canadian-US study (19 case/control pairs) included Ruminococaccaeae and Lachnospiraceae (p < 0.05). Macronutrient intake was not significantly different between cases and controls, minimizing the potential for dietary confounding. INTERPRETATION: Our results suggest that short-chain fatty acid producers may be important contributors to multiple sclerosis onset.

Stroke Outcomes and Hyperacute Treatment Utilization in Multiple Sclerosis.

BACKGROUND: People with MS (pwMS) have higher prevalence of comorbidities at disease onset and face increased risk of developing cardiovascular disorders. Stroke is of particular concern for this population with previous neurological disability. However, data on stroke outcomes and resource utilization in those pwMS remains scarce. OBJECTIVE: To assess the risk of adverse stroke outcomes and hyperacute treatment utilization for pwMS in a U.S. population-based sample of hospitalized patients. METHODS: This study identified patients discharged with a diagnosis of ischemic stroke in the 2018 National Inpatient Sample. We compared the discharge outcomes and hyperacute stroke treatment utilization in MS (n = 2,795) versus non-MS patients (n = 682.730). Regression models adjusted for cardiovascular risk factors and hospital characteristics were used to account for the complex sampling design. RESULTS: The odds of a good discharge were 32% less likely to occur in pwMS (adj.OR 0.68 [95%CI 0.58-0.81], p<0.001). However, this was not associated with an increased risk of mortality. PwMS had a 57% reduction in the risk of receiving endovascular thrombectomy (EVT) (adj.OR 0.43 [95%CI 0.22-0.83], p = 0.01) but no difference in rates of thrombolysis. CONCLUSION: Patients with MS have lower rates of good discharge outcomes and EVT with ischemic stroke, despite similar rates of thrombolysis.

N-Acetyl Cysteine as a Neuroprotective Agent in Progressive Multiple Sclerosis (NACPMS) trial: Study protocol for a randomized, double-blind, placebo-controlled add-on phase 2 trial.

INTRODUCTION: Patients with progressive multiple sclerosis (PMS) experience relentless disability worsening. Current approved therapies have very modest effects on disability progression and purely focus on immunomodulation. While some inflammatory processes exist in non-active PMS, other biological processes such as neuronal injury from oxidative stress are likely more critical. N-acetyl cysteine (NAC) directly scavenges free radicals and restores neuronal glutathione, a major endogenous antioxidant. Our group has recently evaluated the safety of high dose NAC in a pilot trial in PMS with no tolerability concerns. We aim now to assess the safety, tolerability, and effect of NAC on progression of several MRI, clinical and biological markers in PMS patients. METHODS: The NACPMS trial is a multi-site, randomized, double-blind, parallel-group, placebo-controlled add-on phase 2 trial. Ninety-eight PMS patients with EDSS 3.0-7.0 and aged 40-70 years will be randomized to NAC 1200 mg TID or matching placebo (1:1) as an add-on to the standard of care stratified by site and disease type during a 15-month intervention period. It is hypothesized that a reduction in oxidative stress injury will lessen brain atrophy estimated by MRI. The primary outcome analysis will compare the percent change over 12 months (Month 15 vs Month 3) between treatment and control arms using multivariable linear regression adjusted by age, sex, and disease duration. ETHICS: This study was approved by the Institutional Review Board at the University of California, San Francisco (IRB21-34143), and an Investigational New Drug approval was obtained from the FDA (IND127184). TRIAL REGISTRATION: NCT05122559.