Paradigm shifts in multiple sclerosis management: Implications for daily clinical practice.

Multiple sclerosis (MS) is the most common chronic inflammatory neurological disease. The emergence of disease-modifying therapies (DMTs) has greatly improved disease activity control and progression of disability in MS patients. DMTs differ in their mode of action, route of administration, efficacy, and safety profiles, offering multiple options for clinicians. Personalized medicine aims at tailoring the therapeutic strategy to patients' characteristics and disease activity but also patients' needs and preferences. New therapeutic options have already changed treatment paradigms for patients with active relapsing MS (RMS). The traditional approach consists in initiating treatment with moderate-efficacy DMTs and subsequently, escalating to higher-efficacy DMTs when there is evidence of clinical and/or radiological breakthrough activity. Recent real-world studies suggest that initiation of high-efficacy DMTs from disease onset can improve long-term outcomes for RMS patients. In this article, we review different treatment strategies and discuss challenges associated with personalized therapy.

Impact of methodological choices in comparative effectiveness studies: application in natalizumab versus fingolimod comparison among patients with multiple sclerosis.

BACKGROUND: Natalizumab and fingolimod are used as high-efficacy treatments in relapsing-remitting multiple sclerosis. Several observational studies comparing these two drugs have shown variable results, using different methods to control treatment indication bias and manage censoring. The objective of this empirical study was to elucidate the impact of methods of causal inference on the results of comparative effectiveness studies. METHODS: Data from three observational multiple sclerosis registries (MSBase, the Danish MS Registry and French OFSEP registry) were combined. Four clinical outcomes were studied. Propensity scores were used to match or weigh the compared groups, allowing for estimating average treatment effect for treated or average treatment effect for the entire population. Analyses were conducted both in intention-to-treat and per-protocol frameworks. The impact of the positivity assumption was also assessed. RESULTS: Overall, 5,148 relapsing-remitting multiple sclerosis patients were included. In this well-powered sample, the 95% confidence intervals of the estimates overlapped widely. Propensity scores weighting and propensity scores matching procedures led to consistent results. Some differences were observed between average treatment effect for the entire population and average treatment effect for treated estimates. Intention-to-treat analyses were more conservative than per-protocol analyses. The most pronounced irregularities in outcomes and propensity scores were introduced by violation of the positivity assumption. CONCLUSIONS: This applied study elucidates the influence of methodological decisions on the results of comparative effectiveness studies of treatments for multiple sclerosis. According to our results, there are no material differences between conclusions obtained with propensity scores matching or propensity scores weighting given that a study is sufficiently powered, models are correctly specified and positivity assumption is fulfilled.

Atypical myelitis in patients with multiple sclerosis: Characterization and comparison with typical multiple sclerosis and neuromyelitis optica spectrum disorders.

BACKGROUND: Atypical myelitis in multiple sclerosis (MS) is characterized by extensive myelitis in the longitudinal (longitudinally extensive transverse myelitis) or axial plane (transverse myelitis). OBJECTIVE: To characterize a cohort of MS patients with atypical myelitis. METHODS: Atypical myelitis was extracted from the French and Luxembourg MS databases and compared to two cohorts of MS patients with typical myelitis and neuromyelitis optica spectrum disorders (NMOSDs) patients with myelitis. RESULTS: We enrolled 28 MS patients with atypical myelitis, 68 MS patients with typical myelitis and 119 NMOSD patients with a first episode of myelitis. MS patients with atypical myelitis were characterized by a mean age of 34.0 (±10.7) years and 64.3% were women. In 82.1% of the patients, atypical myelitis was the first episode of MS. Mean Expanded Disability Status Scale (EDSS) scores at nadir and 3-6 months after onset were 4.1 ± 2.1 and 3.3 ± 2, respectively. Differences between groups revealed a predominance of cervicothoracic myelitis and a higher level of disability in NMOSD patients. Disability in MS patients with atypical myelitis was more severe than in the MS patients with typical myelitis; 28% had already converted to progressive MS within our mean follow-up of 39.6 (±30.4) months. CONCLUSION: Atypical myelitis may be the first presentation of MS and is associated with poorer prognosis.