Ongoing randomized clinical trials on HSCT in multiple sclerosis.

Autologous hematopoietic stem cell transplantation (AHSCT) is emerging as a potent treatment for highly active relapsing remitting multiple sclerosis (RRMS), potentially surpassing the efficacy of traditional disease-modifying therapies (DMTs). Phase II and III randomized controlled trials (RCTs) have demonstrated AHSCT's superiority in reducing relapse rates and delaying disability progression compared to standard DMTs. Despite the evolution of treatment guidelines, questions persist regarding patient selection criteria and optimal conditioning regimens. Notably, ongoing clinical trials in the United Kingdom, the United States, Italy, and Norway aim to address these uncertainties by evaluating the safety, efficacy, and long-term outcomes of AHSCT vs. high efficacy DMTs in both DMT-experienced and treatment-naïve patients with active RRMS or aggressive multiple sclerosis (MS). These trials promise to provide valuable insights into the positioning of AHSCT within the treatment landscape of MS.

Patient Preference for Subcutaneous Versus Intravenous Administration with Every-6-Week Natalizumab (Tysabri®) Dosing: NOVA Phase IIIb Extension Study (Part 2).

INTRODUCTION: Following NOVA (part 1) and the approval of the subcutaneous (SC) route of administration of natalizumab by the European Medicines Agency, an extension phase of the NOVA phase IIIb study (part 2) was initiated to collect patient preference data for SC versus intravenous (IV) dosing in patients receiving every-6-week (Q6W) dosing of natalizumab. This study was performed to evaluate patient preference for SC versus IV natalizumab administration and explore the efficacy, safety, and pharmacology characteristics of both routes of administration. METHODS: In part 2, participants received natalizumab (Tysabri®) 300 mg via IV infusion Q6W for 36 weeks and then were randomized to 48 weeks of crossover treatment (24 weeks SC Q6W and 24 weeks IV Q6W, or vice versa). The primary endpoint was the proportion of participants who indicated a preference for natalizumab SC administration on the Patient Preference Questionnaire. RESULTS: A total of 153 participants were randomized in NOVA part 2. Of 123 with patient preference data, 108 (87.8%) preferred the SC route of administration for natalizumab over the IV route; 102 (82.9%) specified "requires less time in the clinic" as the reason for the SC preference. CONCLUSION: In NOVA (part 2), most participants on Q6W dosing of natalizumab preferred SC administration versus IV administration. CLINICALTRIALS: GOV: NCT03689972. INFOGRAPHIC.

Efficacy of Ofatumumab and Teriflunomide in Patients With Relapsing MS From Racial/Ethnic Minority Groups: ASCLEPIOS I/II Subgroup Analyses.

BACKGROUND AND OBJECTIVES: Race and ethnicity may influence the efficacy of disease-modifying therapies in patients with multiple sclerosis (MS). Incidence of MS in ethnically diverse groups may be higher; however, these populations are under-represented in MS trials. This post hoc analysis compared the proportion of patients achieving 3-parameter no evidence of disease activity (NEDA-3) with ofatumumab vs teriflunomide in participants with relapsing MS (RMS) enrolled in the ASCLEPIOS I/II trials by race/ethnicity subgroup. METHODS: ASCLEPIOS I/II were identical, double-blind, double-dummy, active-controlled, multicenter, phase 3 trials. Participants were randomized (1:1) to receive ofatumumab 20 mg every 4 weeks or teriflunomide 14 mg once daily for up to 30 months. Pooled data were used to determine the efficacy/safety of ofatumumab vs teriflunomide in participants who self-identified as non-Hispanic Black, non-Hispanic Asian, Hispanic/Latino, or non-Hispanic White. Participants who did not self-identify into one of these groups were classified as other/unknown. RESULTS: Of the 1,882 participants, 64 (3.4%) self-identified as non-Hispanic Black, 71 (3.8%) as non-Hispanic Asian, 145 (7.7%) as Hispanic/Latino, and 1,538 (81.7%) as non-Hispanic White. Baseline participant demographics/characteristics were largely balanced across subgroups, aside from minor variations in sex, disease duration, and MRI lesions. From months 0 to 24, the proportion of ofatumumab vs teriflunomide-treated patients achieving NEDA-3 (odds ratio [95% CI]) was as follows: non-Hispanic Black, 33.3% vs 3.4% (15.9 [1.67-151.71; p = 0.0162]); non-Hispanic Asian, 42.9% vs 21.9% (3.18 [0.95-10.59; p = 0.06]); Hispanic/Latino, 36.6% vs 18.6% (3.21 [1.32-7.79; p = 0.01]); and non-Hispanic White, 37.4% vs 16.6% (3.57 [2.73-4.67; p < 0.0001]). Rates of AEs were generally similar between treatment groups and across race/ethnicity subgroups; no new or unexpected safety signals were identified. DISCUSSION: Ofatumumab was associated with greater proportions of NEDA-3 achievement than teriflunomide across race/ethnicity subgroups in the ASCLEPIOS trials. Within each treatment group, the proportion of patients achieving NEDA-3 from months 0 to 24 was similar across the subgroups and overall pooled population. Both ofatumumab and teriflunomide were well tolerated. Future MS trials should include ethnically diverse groups to better inform treatment decisions and improve real-world patient outcomes. TRIAL REGISTRATION INFORMATION: ClinicalTrials.gov: NCT02792218 (clinicaltrials.gov/ct2/show/NCT02792218), NCT02792231 (clinicaltrials.gov/ct2/show/NCT02792231). Submission date: June 2, 2016. First enrollment: August 26, 2016. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that among patients aged 18-55 years with RMS, the improvement in NEDA-3 with ofatumumab was comparably better than with teriflunomide among patients self-identified as non-Hispanic Black, non-Hispanic Asian, non-Hispanic White, Hispanic/Latino, and other/unknown.

Review of the Longitudinal Management of Autoimmune Encephalitis, Potential Biomarkers, and Novel Therapeutics.

Purpose of Review: Increasing awareness and earlier diagnosis of autoimmune encephalitis (AE) have led to a greater number of patients being cared for longitudinally by neurologists. Although many neurologists are now familiar with the general approach to diagnosis and acute immunosuppression, this review aims to provide neurologists with guidance related to management beyond the acute phase of disease, including long-term immunosuppression, monitoring, potential biomarkers of disease activity, outcome measures, and symptom management. Recent Findings: Observational studies in AE have demonstrated that early diagnosis and treatment is associated with improved neurologic outcomes, particularly in AE with antibodies targeting neuronal cell surface/synaptic proteins. The literature regarding long-term management is evolving. In addition to traditional immunosuppressive approaches, there is emerging use of novel immunosuppressive therapies (ISTs) in case series, and several randomized controlled trials are planned. Novel biomarkers of disease activity and methods to measure outcomes and response to treatment are being explored. Furthermore, it is increasingly recognized that many individuals have chronic symptoms affecting quality of life including seizures, cognitive impairment, fatigue, sleep disorders, and mood disorders, and there are emerging data supporting the use of patient centered outcome measures and multidisciplinary symptom-based care. Summary: This review aims to summarize recent literature and offer a practical approach to long-term management of adult patients with AE through a multidisciplinary approach. We summarize current knowledge on ISTs, potential biomarkers of disease activity, outcome measures, and long-term sequelae. Further research is needed to answer questions regarding optimal IST, biomarker validity, and sequelae of disease.

Management of multiple sclerosis in older adults: review of current evidence and future perspectives.

IMPORTANCE: The prevalence of multiple sclerosis (MS) and aging MS patients is increasing worldwide. There is a need to better understand this MS sub-population, which historically is underrepresented in the literature. This narrative review examines the evolving demographics, disease course, and treatments for older adults with MS (OAMS) to address current knowledge gaps and highlight areas critical for future research. OBSERVATIONS: OAMS populations require special consideration by clinicians. Older individuals have different care needs than individuals with adult onset MS who are mid-life or younger. Comorbidities, an aging immune system, increasing neurodegeneration, decreasing neurologic reserve, changing benefit/risk relationship for disease modifying therapies (DMTs), and wellness require special attention to provide holistic comprehensive care. Active areas of research include potential cessation of DMTs and novel disease targets. CONCLUSIONS AND RELEVANCE: This review highlights both the current knowledge and information gaps in the literature that are critical to understanding and properly managing OAMS. The aims are to inform MS clinicians in their current practice, as well as inspire future studies which are critical to providing quality and evidence-based care for OAMS.

Virtual versus usual in-office care for multiple sclerosis: The VIRTUAL-MS multi-site randomized clinical trial study protocol.

BACKGROUND: Multiple sclerosis (MS) affects nearly 1 million people and is estimated to cost $85.4 billion in the United States annually. People with MS have significant barriers to receiving care and telemedicine could substantially improve access to specialized, comprehensive care. In cross-sectional analyses, telemedicine has been shown to be feasible, have high patient and clinician satisfaction, reduce patient costs and burden, and enable a reasonable assessment of disability. However, no studies exist evaluating the longitudinal impact of telemedicine care for MS. Here we describe the study protocol for VIRtual versus UsuAL In-office care for Multiple Sclerosis (VIRTUAL-MS). The main objective of the study is to evaluate the impact of telemedicine for MS care on: patient clinical outcomes, economic costs, patient, and clinician experience. METHODS: This two-site randomized clinical trial will enroll 120 adults with a recent diagnosis of MS and randomize 1:1 to receive in-clinic vs. telemedicine care for 24 months. The primary outcome of the study is worsening in any one of the four Multiple Sclerosis Functional Composite 4 (MSFC4) measures at 24 months. Other study outcomes include patient and clinician satisfaction, major healthcare costs, Expanded Disability Status Scale, treatment adherence, and digital outcomes. CONCLUSION: The results of this study will directly address the key gaps in knowledge about longitudinal telemedicine-enabled care in an MS population. It will inform clinical care implementation as well as design of trials in MS and other chronic conditions. TRIAL REGISTRATION: NCT05660187.

Drugs Targeting CD20 in Multiple Sclerosis: Pharmacology, Efficacy, Safety, and Tolerability.

Currently, there are four monoclonal antibodies (mAbs) that target the cluster of differentiation (CD) 20 receptor available to treat multiple sclerosis (MS): rituximab, ocrelizumab, ofatumumab, and ublituximab. B-cell depletion therapy has changed the therapeutic landscape of MS through robust efficacy on clinical manifestations and MRI lesion activity, and the currently available anti-CD20 mAb therapies for use in MS are a cornerstone of highly effective disease-modifying treatment. Ocrelizumab is currently the only therapy with regulatory approval for primary progressive MS. There are currently few data regarding the relative efficacy of these therapies, though several clinical trials are ongoing. Safety concerns applicable to this class of therapeutics relate primarily to immunogenicity and mechanism of action, and include infusion-related or injection-related reactions, development of hypogammaglobulinemia (leading to increased infection and malignancy risk), and decreased vaccine response. Exploration of alternative dose/dosing schedules might be an effective strategy for mitigating these risks. Future development of biosimilar medications might make these therapies more readily available. Although anti-CD20 mAb therapies have led to significant improvements in disease outcomes, CNS-penetrant therapies are still needed to more effectively address the compartmentalized inflammation thought to play an important role in disability progression.

Progressive Encephalomyelopathy in an Older Man: A Case Report From the National Multiple Sclerosis Society Case Conference Proceedings.

We present a case of subacute onset progressive encephalomyelopathy in a 77-year-old man with symmetric lateral column signal abnormalities on spinal MRI. We discuss the differential and presumptive final diagnosis along with a review of the postulated disease immunopathogenesis.

Ibudilast reduces slowly enlarging lesions in progressive multiple sclerosis.

BACKGROUND: Ibudilast has shown beneficial effects on several imaging outcomes in progressive multiple sclerosis (MS). Slowly enlarging lesions are a proposed imaging biomarker of compartmentalized inflammation within chronic active lesions. OBJECTIVE: To assess the treatment effect of ibudilast on slowly enlarging lesion volumes over 96 weeks from a phase II clinical trial of ibudilast (Secondary and Primary Progressive Ibudilast NeuroNEXT Trial in Multiple Sclerosis [SPRINT-MS]). METHODS: In total, 255 participants with progressive MS from 28 sites were randomized to oral ibudilast or placebo. Participants with at least four analyzable magnetic resonance imaging (MRI) were included. Slowly enlarging lesions were quantified using Jacobian determinant maps. A linear model was used to assess the effect of ibudilast. Magnetization transfer ratio within slowly enlarging lesions was assessed to determine the effect of ibudilast on tissue integrity. RESULTS: In total, 195 participants were included in this analysis. Ibudilast significantly decreased slowly enlarging lesion volume (23%, p = 0.003). Ibudilast also reduced magnetization transfer ratio change in slowly enlarging lesions: 0.22%/year, p = 0.04. CONCLUSION: Ibudilast showed a significant effect on baseline volume of lesions that were slowly enlarging and magnetization transfer ratio in slowly enlarging lesions. The results support the use of slowly enlarging lesions for assessment of compartmentalized inflammation represented by chronic active lesions and provide further support for the neuroprotective effects of ibudilast in progressive MS.

Longitudinal Disability, Cognitive Impairment, and Mood Symptoms in Patients With Anti-NMDA Receptor Encephalitis.

BACKGROUND AND OBJECTIVES: Longitudinal outcomes in anti-NMDA receptor encephalitis (anti-NMDARe) are still not fully understood and may not be adequately captured with the modified Rankin Scale (mRS), often the sole reported outcome. We aim to characterize longitudinal outcomes in anti-NMDARe using multiple outcome measures. METHODS: This single-center, retrospective, observational study examined outcome measures (mRS and Clinical Assessment Scale in Autoimmune Encephalitis [CASE]) in adults with NMDA receptor-IgG in CSF at short- and long-term follow-ups using linear and logistic regression modeling. Patients with evaluations for cognitive impairment (Montreal Cognitive Assessment/Mini-Mental State Examination), depression (Patient Health Questionnaire-9), and anxiety (General Anxiety Disorder-7) >6 months from symptom onset were correlated with final CASE scores. RESULTS: Thirty-eight patients (76% female, median disease onset age = 28 years, range = 1-75 years) were included. The majority received first-line immunosuppressants (97%) at a median of 3.9 weeks (interquartile range [IQR] = 2.1-9.7) from symptom onset and 68% received second-line therapies. At baseline, median/mean mRS and CASE were 4 (IQR = 3-5) and 12.9 (SD = 7.2), respectively. At short-term follow-up (median = 10 weeks, IQR = 6-17), factors associated with higher CASE and mRS included dysautonomia, coma/lethargy, seizures/status epilepticus, and intensive care unit admission (p < 0.05). At long-term follow-up (median = 70 weeks, IQR = 51-174), median/mean mRS and CASE were 2 (IQR = 1-3) and 4.4 (SD = 4.2), respectively. Only weakness at symptom onset predicted higher mRS scores (odds ratio = 5.6, 95% confidence interval 1.02-30.9, p = 0.047). Despite both mRS and CASE improving from baseline (p < 0.001), only 9 patients (31%) returned to their premorbid function. Among patients with cognitive and mood evaluations >6 months from onset, moderate-severe cognitive impairment (42%), depression (28%), and anxiety (30%) were frequent. Cognitive and depression measures were associated with final CASE subscores (including memory, language, weakness, and psychiatric). DISCUSSION: Multiple clinical factors influenced short-term outcomes, but only onset weakness influenced long-term mRS, highlighting that mRS is predominantly affected by global motor function. Although mRS and CASE improved over time for most patients, these outcome measures did not capture the full extent of long-term functional impairment in terms of mood, cognition, and the ability to return to premorbid function. This emphasizes the need for increased utilization of more nuanced cognitive and mood outcome measures.

Predicting disability and mortality in CV2/CRMP5-IgG associated paraneoplastic neurologic disorders.

BACKGROUND: We aimed to investigate the prognostic factors associated with clinical outcomes in CV2/Collapsin response-mediator protein 5 (CRMP5)-IgG paraneoplastic neurologic disorders (PND). METHODS: This is a retrospective study of patients with CV2/CRMP5-IgG PND evaluated between 2002-2022. We examined the association of clinical variables (including age, clinical phenotype [autoimmune encephalopathy, myelopathy, polyneuropathy/radiculopathy, MG, cerebellar ataxia, chorea, optic neuropathy], cancer) with three clinical outcomes (wheelchair dependence, modified Rankin Scale [mRS], mortality) using univariate logistic regression and Cox proportional hazards modeling. Kaplan-Meier estimates were used to determine the probability of survival. RESULTS: Twenty-seven patients (56% female) with CV2/CRMP5-IgG PND were identified with a median follow-up of 54 months (IQR = 11-102). An underlying tumor was identified in 15 patients (56%) including small cell lung cancer (SCLC) (8, [53%]), thymoma (4, [27%]), and other histologies (3, [20%]). At last follow-up, 10 patients (37%) needed a wheelchair for mobility and this outcome was associated with myelopathy (HR = 7.57, 95% CI = 1.87-30.64, P = 0.005). Moderate-severe mRS = 3-5 was associated with CNS involvement (encephalopathy, myelopathy, or cerebellar ataxia) (OR = 7.00, 95% CI = 1.18-41.36, P = 0.032). The probability of survival 4 years after symptom onset was 66%. Among cancer subtypes, SCLC (HR = 18.18, 95% CI = 3.55-93.04, P < 0.001) was significantly associated with mortality, while thymoma was not. INTERPRETATION: In this retrospective longitudinal study of CV2/CRMP5-IgG PND, patients with CNS involvement, particularly myelopathy, had higher probability of disability. SCLC was the main determinant of survival in this population.

Concurrent administration of serotonergic antidepressants and ozanimod in participants with relapsing multiple sclerosis from the open-label extension DAYBREAK trial.

BACKGROUND: Monoamine oxidase (MAO) inhibitors can interact with selective serotonin reuptake inhibitors (SSRIs)/serotonin-norepinephrine reuptake inhibitors (SNRIs). There is clinical interest surrounding use of ozanimod with SSRIs/SNRIs because the major metabolites of ozanimod are weak inhibitors of MAO-B in vitro. OBJECTIVE: To evaluate the incidence of treatment-emergent adverse events (TEAEs) potentially related to serotonin accumulation (SA) during concomitant ozanimod and SSRI/SNRI use by performing analyses of data from an open-label, oral ozanimod 0.92 mg trial (DAYBREAK; NCT02576717). METHODS: SA narrow (serotonin syndrome, neuroleptic malignant syndrome, and hyperthermia malignant) and broad (terms potentially associated with SA) MedDRA v24.0 searches were performed using TEAE data from participants with relapsing multiple sclerosis who entered DAYBREAK from phase 3 studies (cutoff February 1, 2022). Incidences of TEAEs matching terms from each search were stratified by SSRI/SNRI use. RESULTS: Of 2257 DAYBREAK participants, 274 (12.1%) used an SSRI/SNRI. No participants had TEAEs matching the SA narrow search terms. There was no significant difference in the percentage of participants with ⩾1 TEAE matching the SA broad search for those on versus off SSRIs/SNRIs (on: 12.4%, n = 34/274; off: 15.6%, n = 310/1982, nominal p = 0.1630). CONCLUSION: MedDRA searches showed no increase in TEAEs potentially associated with SA with concomitant SSRI/SNRI and ozanimod use.

Magnetic resonance fingerprinting in multiple sclerosis.

BACKGROUND: In this cross sectional study, we used MRF to investigate tissue properties of normal-appearing white matter, gray matter, and lesions in relapsing remitting MS (n = 21), secondary progressive MS (n = 16) and healthy controls (n = 9). A FISP-based MRF sequence was used for acquisition, imaging time 5 min 15 s. MRF T1 and T2 relaxation times were measured from lesional tissue, normal-appearing frontal white matter, corpus callous, thalamus, and caudate. Differences between healthy controls and MS were examined using ANCOVA adjusted for age and sex. Spearman rank correlations were assessed between T1 and T2 relaxation times and clinical measures. OBJECTIVES: To examine brain T1 and T2 values using magnetic resonance fingerprinting (MRF) in healthy controls and MS. METHODS: The subjects included 21 relapsing-remitting (RR) MS, 16 secondary progressive (SP) MS, and 9 age- and sex-matched HC without manifest neurological disease participating in a longitudinal MRI study. A 3T/ FISP-based MRF sequence was acquired. Regions of interest were drawn for lesions and normal appearing white matter. ANCOVA adjusted for age and sex were used to compare the groups with significance set at 0.05. RESULTS: A step-wise increase in T1 and T2 relaxation times was found between healthy controls, relapsing remitting MS, and secondary progressive MS. Significant differences were found in T1 and T2 between MS and healthy controls in the frontal normal-appearing white matter, corpus callosum, and thalamus (p < 0.04 for all). Significant differences in T1 and T2 between RR and SPMS were found in the frontal normal-appearing white matter and T2 lesions (p < 0.02 for all). T1 relaxation from the frontal normal-appearing white matter correlated with the Expanded Disability Status Scale [ρ = 0.62, p < 0.001], timed 25 foot walk (ρ = 0.45, p = 0.01), 9 hole peg test (ρ = 0.62, p < 0.001), and paced auditory serial addition test (ρ = -0.4, p = 0.01). CONCLUSION: These results suggest that MRF may be a clinically feasible quantitative approach for characterizing tissue damage in MS.

Efficacy and safety of four-year ofatumumab treatment in relapsing multiple sclerosis: The ALITHIOS open-label extension.

BACKGROUND: Ofatumumab has demonstrated superior efficacy and favorable safety for up to 2.5 years versus teriflunomide in relapsing multiple sclerosis (RMS). OBJECTIVE: Further characterize efficacy and safety of ofatumumab in RMS. METHODS: Efficacy set: patients randomized to ofatumumab/teriflunomide in ASCLEPIOS I/II (core). Safety set: patients who received ⩾ 1 dose of ofatumumab in ASCLEPIOS I/II, APLIOS, APOLITOS (all core), or ALITHIOS (umbrella open-label extension). Patients received continuous ofatumumab or were newly switched from teriflunomide. Data cut-off: 25 September 2021. RESULTS: In the efficacy set (n = 1882), the continuous ofatumumab group had a low annualized relapse rate (ARR 0.05 (95% confidence interval: 0.04-0.07)), low numbers of gadolinium-enhancing (Gd+) T1 lesions (0.01 lesions/scan) and fewer new/enlarging T2 lesions (annualized rate 0.08). Overall, 78.8% met three-parameter "no evidence of disease activity" criteria through 4 years. Switching from teriflunomide led to reduced ARR, risk of confirmed disability worsening (CDW), new/enlarging T2 lesions, Gd+ T1 lesions, and serum neurofilament light chain. In the continuous and newly switched ofatumumab groups, cumulative 3- and 6-month CDW rates remained low. In the safety set (n = 1969), the most frequently reported adverse events were infections and infestations (58.35%). No new safety signals were identified. CONCLUSION: Ofatumumab has a favorable longer-term benefit-risk profile in RMS. TRIAL REGISTRY: ALITHIOS (NCT03650114): https://clinicaltrials.gov/ct2/show/NCT03650114.

Effect of ibudilast on thalamic magnetization transfer ratio and volume in progressive multiple sclerosis.

BACKGROUND: Thalamic volume (TV) is a sensitive biomarker of disease burden of injury in multiple sclerosis (MS) and appears to reflect overall lesion loads. Ibudilast showed significant treatment effect on brain atrophy and magnetization transfer ratio (MTR) of normal-appearing brain tissue but not in new/enlarging T2 lesion in the SPRINT-MS randomized clinical trial. OBJECTIVE: To evaluate the effect of ibudilast on thalamic tissue integrity and volume in the SPRINT-MS. METHODS: A total of 255 participants with progressive MS were randomized to oral ibudilast or placebo, and thalamic MTR and normalized TV over 96 weeks were quantified. Mixed-effect modeling assessed treatment effects on the thalamic MTR and TV, separately. Similarly, the measures were compared between the participants with confirmed disability progression (CDP). RESULTS: Ibudilast's treatment effect was observed compared to placebo for thalamic MTR (p = 0.03) but not for TV (p = 0.68) while TV correlated with T2 lesion volume (p < 0.001). CDP associated with thalamic MTR (p = 0.04) but not with TV (p = 0.7). CONCLUSION: Ibudilast showed an effect on thalamic MTR, which was associated with CDP, suggesting a clinically relevant effect on thalamic tissue integrity. However, the treatment effect was not observed in TV, suggesting that thalamic atrophy is more closely associated with global inflammatory activity than local tissue integrity. CLINICALTRIALS.GOV: NCT01982942.

Differential diagnosis of suspected multiple sclerosis: an updated consensus approach.

Accurate diagnosis of multiple sclerosis requires careful attention to its differential diagnosis-many disorders can mimic the clinical manifestations and paraclinical findings of this disease. A collaborative effort, organised by The International Advisory Committee on Clinical Trials in Multiple Sclerosis in 2008, provided diagnostic approaches to multiple sclerosis and identified clinical and paraclinical findings (so-called red flags) suggestive of alternative diagnoses. Since then, knowledge of disorders in the differential diagnosis of multiple sclerosis has expanded substantially. For example, CNS inflammatory disorders that present with syndromes overlapping with multiple sclerosis can increasingly be distinguished from multiple sclerosis with the aid of specific clinical, MRI, and laboratory findings; studies of people misdiagnosed with multiple sclerosis have also provided insights into clinical presentations for which extra caution is warranted. Considering these data, an update to the recommended diagnostic approaches to common clinical presentations and key clinical and paraclinical red flags is warranted to inform the contemporary clinical evaluation of patients with suspected multiple sclerosis.

The impact of cigarette smoking on cognitive processing speed and brain atrophy in multiple sclerosis.

BACKGROUND: Smoking is associated with an increased risk of multiple sclerosis (MS) and disability worsening. The relationship between smoking, cognitive processing speed, and brain atrophy remains uncertain. OBJECTIVE: To quantify the impact of smoking on processing speed and brain volume in MS and to explore the longitudinal relationship between smoking and changes in processing speed. METHODS: A retrospective study of MS patients who completed the processing speed test (PST) between September 2015 and March 2020. Demographics, disease characteristics, smoking history, and quantitative magnetic resonance imaging (MRI) were collected. Cross-sectional associations between smoking, PST performance, whole-brain fraction (WBF), gray matter fraction (GMF), and thalamic fraction (TF) were assessed using multivariable linear regression. The longitudinal relationship between smoking and PST performance was assessed by linear mixed modeling. RESULTS: The analysis included 5536 subjects of whom 1314 had quantitative MRI within 90 days of PST assessment. Current smokers had lower PST scores than never smokers at baseline, and this difference persisted over time. Smoking was associated with reduced GMF but not with WBF or TF. CONCLUSION: Smoking has an adverse relationship with cognition and GMF. Although causality is not demonstrated, these observations support the importance of smoking cessation counseling in MS management.