The T1-dark-rim: A novel imaging sign for detecting smoldering inflammation in multiple sclerosis.

PURPOSE: Paramagnetic rim lesions (PRLs), usually identified in susceptibility-weighted imaging (SWI), are a promising prognostic biomarker of disability progression in multiple sclerosis (MS). However, SWI is not routinely performed in clinical practice. The objective of this study is to define a novel imaging sign, the T1-dark rim, identifiable in a standard 3DT1 gradient-echo inversion-recovery sequence, such as 3D T1 turbo field echo (3DT1FE) and explore its performance as a SWI surrogate to define PRLs. METHODS: This observational cross-sectional study analyzed MS patients who underwent 3T magnetic resonance imaging (MRI) including 3DT1TFE and SWI. Rim lesions were evaluated in 3DT1TFE, processed SWI, and SWI phase and categorized as true positive, false positive, or false negative based on the value of the T1-dark rim in predicting SWI phase PRLs. Sensitivity and positive predictive values of the T1-dark rim for detecting PRLs were calculated. RESULTS: Overall, 80 rim lesions were identified in 63 patients (60 in the SWI phase and 78 in 3DT1TFE; 58 true positives, 20 false positives, and two false negatives). The T1-dark rim demonstrated 97% sensitivity and 74% positive predictive value for detecting PRLs. More PRLs were detected in the SWI phase than in processed SWI (60 and 57, respectively). CONCLUSION: The T1-dark rim sign is a promising and accessible novel imaging marker to detect PRLs whose high sensitivity may enable earlier detection of chronic active lesions to guide MS treatment escalation. The relevance of T1-dark rim lesions that are negative on SWI opens up a new field for analysis.

Deeply 3D-T1-TFE hypointense voxels are characteristic of phase-rim lesions in multiple sclerosis.

OBJECTIVES: The development of new drugs for the treatment of progressive multiple sclerosis (MS) highlights the need for new prognostic biomarkers. Phase-rim lesions (PRLs) have been proposed as markers of progressive disease but are difficult to identify and quantify. Previous studies have identified T1-hypointensity in PRLs. The aim of this study was to compare the intensity profiles of PRLs and non-PRL white-matter lesions (nPR-WMLs) on three-dimensional T1-weighted turbo field echo (3DT1TFE) MRI. We then evaluated the performance of a derived metric as a surrogate for PRLs as potential markers for risk of disease progression. METHODS: This study enrolled a cohort of relapsing-remitting (n = 10) and secondary progressive MS (n = 10) patients for whom 3 T MRI was available. PRLs and nPR-WMLs were segmented, and voxel-wise normalized T1-intensity histograms were analyzed. The lesions were divided equally into training and test datasets, and the fifth-percentile (p5)-normalized T1-intensity of each lesion was compared between groups and used for classification prediction. RESULTS: Voxel-wise histogram analysis showed a unimodal histogram for nPR-WMLs and a bimodal histogram for PRLs with a large peak in the hypointense limit. Lesion-wise analysis included 1075 nPR-WMLs and 39 PRLs. The p5 intensity of PRLs was significantly lower than that of nPR-WMLs. The T1 intensity-based PRL classifier had a sensitivity of 0.526 and specificity of 0.959. CONCLUSIONS: Profound hypointensity on 3DT1TFE MRI is characteristic of PRLs and rare in other white-matter lesions. Given the widespread availability of T1-weighted imaging, this feature might serve as a surrogate biomarker for smoldering inflammation. CLINICAL RELEVANCE STATEMENT: Quantitative analysis of 3DT1TFE may detect deeply hypointense voxels in multiple sclerosis lesions, which are highly specific to PRLs. This could serve as a specific indicator of smoldering inflammation in MS, aiding in early detection of disease progression. KEY POINTS: • Phase-rim lesions (PRLs) in multiple sclerosis present a characteristic T1-hypointensity on 3DT1TFE MRI. • Intensity-normalized 3DT1TFE can be used to systematically identify and quantify these deeply hypointense foci. • Deep T1-hypointensity may act as an easily detectable, surrogate marker for PRLs.

Baseline serum neurofilament light chain levels differentiate aggressive from benign forms of relapsing-remitting multiple sclerosis: a 20-year follow-up cohort.

BACKGROUND AND OBJECTIVES: Serum biomarkers are emerging as useful prognostic tools for multiple sclerosis (MS); however, long-term studies are lacking. We aimed to evaluate the long-term prognostic value of the serum levels of neurofilament light chain (NfL), total tau, glial fibrillary acidic protein (GFAP), and chitinase 3-like-1 (CHI3L1) measured close to the time of MS onset. METHODS: In this retrospective, exploratory, observational, case and controls study, patients with relapsing-remitting MS (RRMS) with available baseline serum samples and prospectively follow-up in our MS unit for a long time were selected based on their clinical evolution to form two groups: (1) a benign RRMS (bRRMS) group, defined as patients with an Expanded Disability Status Scale (EDSS) score of ≤ 3 at ≥ 10 years of follow-up; (2) an aggressive RRMS (aRRMS) group, defined as patients with an EDSS score of ≥ 6 at ≤ 15 years of follow-up. An age-matched healthy control (HC) group was selected. NfL, total tau, and GFAP serum levels were quantified using a single-molecule array (SIMOA), and CHI3L1 was quantified using ELISA. RESULTS: Thirty-one patients with bRRMS, 19 with aRRMS, and 10 HC were included. The median follow-up time from sample collection was 17.74 years (interquartile range, 14.60-20.37). Bivariate and multivariate analyses revealed significantly higher NfL and GFAP levels in the aRRMS group than in the bRRMS group. A receiver operating characteristic curve analysis identified serum NfL level as the most efficient marker for distinguishing aRRMS from bRRMS. DISCUSSION: This proof-of-concept study comparing benign and aggressive RRMS groups reinforces the potential role of baseline NfL serum levels as a promising long-term disability prognostic marker. In contrast, serum GFAP, total tau, and CHI3L1 levels demonstrated a lower or no ability to differentiate between the long-term outcomes of RRMS.

Kappa free light chains index in multiple sclerosis very long-term prognosis.

Introduction: The role of the kappa-free light chain (kFLC) in the diagnosis of multiple sclerosis (MS) and, to a lesser extent, its role as a medium-term prognostic marker have been extensively studied. This study aimed to explore its potential as a long-term prognostic marker for MS. Methods: We performed an exploratory retrospective observational study by selecting patients systemically followed up in our MS unit with available cerebrospinal fluid and serum samples at the time of initial evaluation. Two groups were defined: benign MS (bMS), defined as patients with Expanded Disability Status Scale (EDSS) ≤ 3 at 10 years of follow-up, and aggressive MS (aMS), defined as patients with EDSS ≥ 6 at 15 years of follow-up. Clinical variables were collected, and the immunoglobulin G (IgG) index, kFLC index, and oligoclonal bands (OCB) were determined for all patients and compared between the groups. Results: Twenty bMS and 15 aMS patients were included in this study. Sixty percent (21/35) were female, and the mean age at the time of the first symptom was 31.5 ± 9.45 years, with no statistical differences between groups. Median follow-up time was 19.8 years (Interquartile range, IQR 15.9-24.6). The median EDSS scores at the last follow-up were 1.5 and 7.5 in the bMS and the aMS group, respectively. No statistically significant differences were found in the kFLC index between the two groups (136.6 vs. 140.27, p=0.59). The IgG index was positive in 62.9% of patients (55% bMS vs. 73.3% aMS, p>0.05), and OCB was positive in 88.6% (90% bMS vs. 86.7% aMS, p>0.05). A significant positive correlation was found between IgG and kFLC indices (rs = 0.85, p<0.001). Conclusion: Given the absence of differences between the two groups with opposite disease courses, it is unlikely that the kFLC index is a reliable and powerful marker of long-term prognosis in MS.

Natalizumab continuation versus switching to ocrelizumab after PML risk stratification in RRMS patients: a natural experiment.

BACKGROUND: Natalizumab (NTZ) and ocrelizumab (OCR) can be used for the treatment of relapsing-remitting multiple sclerosis (RRMS). In patients treated with NTZ, screening for JC virus (JCV) is mandatory, and a positive serology usually requires a change in treatment after 2 years. In this study, JCV serology was used as a natural experiment to pseudo-randomize patients into NTZ continuation or OCR. METHODS: An observational analysis of patients who had received NTZ for at least 2 years and were either changed to OCR or maintained on NTZ, depending on JCV serology status, was performed. A stratification moment (STRm) was established when patients were pseudo-randomized to either arm (NTZ continuation if JCV negativity, or change to OCR if JCV positivity). Primary endpoints include time to first relapse and presence of relapses after STRm and OCR initiation. Secondary endpoints include clinical and radiological outcomes after 1 year. RESULTS: Of the 67 patients included, 40 continued on NTZ (60%) and 27 were changed to OCR (40%). Baseline characteristics were similar. Time to first relapse was not significantly different. Ten patients in the JCV + OCR arm presented a relapse after STRm (37%), four during the washout period, and 13 patients in the JCV-NTZ arm (32.5%, p = 0.701). No differences in secondary endpoints were detected in the first year after STRm. CONCLUSIONS: The JCV status can be used as a natural experiment to compare treatment arms with a low selection bias. In our study, switching to OCR versus NTZ continuation led to similar disease activity outcomes.

Direct health costs of amyotrophic lateral sclerosis in a multidisciplinary ALS unit in Catalonia (Spain).

Our research project computed the direct health costs of patients with amyotrophic lateral sclerosis (ALS) in a Spanish multidisciplinary unit and explored the main factors associated. Besides analyzing a context with universal health care provision, we used an administrative health care dataset from the most crucial center unit treating ALS in Catalonia (80% of total patients). Our results show that the direct health cost of caring for an ALS patient in our unit was 5,158€per patient/year. This cost was not influenced by the onset of the disease, sex or age, but it increased if the patient lived near our center since this facilitates the frequency of follow-up visits. Finally, the higher the educational level, the lower the direct health costs.

Effects of Bihemispheric Transcranial Direct Current Stimulation Combined With Repetitive Peripheral Nerve Stimulation in Acute Stroke Patients.

PURPOSE: Transcranial direct current stimulation (tDCS) can change the excitability of the central nervous system and contribute to motor recovery of stroke patients. The aim of our study was to examine the short- and long-term effects of real versus sham bihemispheric tDCS combined with repetitive peripheral nerve stimulation in patients with acute stroke and a severe motor impairment. METHODS: The study was prospective, randomized, double blind, and placebo controlled. Nineteen acute stroke patients (ischemic and hemorrhagic) with upper limb Fugl-Meyer mean score of <19 were randomized in two groups: one group received five consecutive daily sessions of anodal tDCS over the affected hemisphere and cathodal over unaffected hemisphere combined with repetitive peripheral nerve stimulation and the other received sham tDCS associated to repetitive peripheral nerve stimulation. Clinical and neurophysiological assessment was applied before tDCS, 5 days after tDCS, and 3, 6, and 12 months after tDCS. RESULTS: There were significant time-related changes in both groups of patients in motor evoked potentials, somatosensory evoked potentials, Hmax:Mmax ratio, upper limb Fugl-Meyer scores, and Modified Ashworth scales scores ( P < 0.05). However, no significant differences between groups were present at any time ( P > 0.05). CONCLUSIONS: Bihemispheric tDCS and repetitive peripheral nerve stimulation with the parameters of our study did not add significant short- or long-term clinical improvement or change in neurophysiological data in severe acute stroke patients in comparison to sham stimulation. The severity of motor impairment in stroke patients may influence a possible response to an interventional tDCS treatment.

Influence of Cardiovascular Risk Factors in Early Relapsing-Remitting Multiple Sclerosis: A Retrospective Analysis.

INTRODUCTION: Prior studies have suggested that cardiovascular risk factors (CVRFs) can affect the prognosis of multiple sclerosis (MS). The aim of this study was to assess if CVRFs affect the early course of MS. METHODS: A retrospective observational study was performed, including patients diagnosed with relapsing-remitting MS (RRMS) from 2010 to 2020, with at least 2 years of disease and 6 months follow-up. Age at onset, disease duration, number of relapses, time to confirmed Expanded Disability Status Scale (EDSS) 3.0 and 6.0, and time to secondary progressive MS (SPMS) were collected. Presence and date at onset of hypertension (HT), diabetes mellitus (DM), high low-density lipoprotein cholesterol (LDLc), and smoking during the study period were collected. The primary objective was to assess if CVRFs at the onset of MS are associated with lower time to EDSS 3.0, time to EDSS 6.0, and time to SPMS, using bivariate and multivariate analysis. RESULTS: 281 RRMS patients were included; median age at onset was 33 (IQR 26-39); 69.4% were female. Median EDSS at onset was 1.5 (IQR 1-2.5). Nine patients reached SPMS; 24 patients were diagnosed with HT, 9 with DM, 109 with high LDLc, and 123 were smokers during follow-up. No statistically significant association was found between the presence of CVRF at MS onset and the mentioned clinical outcomes during the MS course. CONCLUSION: No association was found between CVRFs and the early course of MS in our cohort.

The age at onset of relapsing-remitting multiple sclerosis has increased over the last five decades.

BACKGROUND: Patients with relapsing-remitting multiple sclerosis (RRMS) most commonly experience their first symptoms between 20 and 40 years of age. The objective of this study was to investigate how the age at which the first symptoms of RRMS occur has changed over the past decades. METHODS: Patients who were followed up in our unit after an initial diagnosis of RRMS using the Poser or McDonald criteria and who experienced their first symptoms between January 1970 and December 2019 were included in the study. The cohort was divided into five groups according to the decade in which the first symptoms appeared. The age at disease onset was compared across decades. Changes in age were also determined after excluding patients with early-onset disease (<18 years of age) and those with late-onset disease (>50 years of age) to avoid bias. RESULTS: The cohort included 1,622 patients with RRMS, 67.6% of whom were women. Among them, 5.9% and 4% had early-onset and late-onset disease, respectively. The mean age ± standard deviation at onset was 31.11 ± 9.82 years, with no differences between men and women. The mean ages at onset were 23.79 ± 10.19 years between 1970 and 1979, 27.86 ± 9.22 years between 1980 and 1989, 30.07 ± 9.32 years between 1990 and 1999, 32.12 ± 9.47 between 2000 and 2009, and 34.28 ± 9.83 years between 2010 and 2019. The ages at disease onset were progressively higher in the later decades; this trend was statistically significant (p < 0.001), with a Pearson linear correlation coefficient R of 0.264 and R2 of 0.070 (p < 0.001). The results were similar when analysing men and women separately. We conducted an analysis of 1,460 patients (mean age at onset: 31.10 ± 7.99 years), after excluding patients with early-onset and late-onset disease. In this specific subgroup, the mean ages at disease onset were 28.38 ± 8.17 years between 1970 and 1979, 29.22 ± 7.51 years between 1980 and 1989, 30.06 ± 8.02 years between 1990 and 1999, 31.46 ± 7.77 years between 2000 and 2009, and 33.37 ± 7.97 years between 2010 and 2019. The trend was also statistically significant (p < 0.001), with a Pearson linear correlation coefficient R of 0.193 and R2 of 0.037 (p < 0.001). CONCLUSION: Our data showed that the age at RRMS onset has increased over the past decades.

Cost associated with a relapse-free patient in multiple sclerosis: A real-world health indicator.

BACKGROUND: The efficacy and safety of disease-modifying therapies (DMTs) in multiple sclerosis (MS) are well known; however, owing to their high costs, determining real-world outcomes is essential to evaluate the cost-effectiveness of different therapeutic strategies. This study aimed to investigate the variability in the annual cost of DMTs associated with a relapse-free patient in a representative population cohort of relapsing-remitting MS (RRMS), and whether this could serve as an appropriate health indicator. METHODS: We analyzed the patients followed up in our MS clinic during the years 2016 and 2019, and selected patients belonging to our health district diagnosed with RRMS. The treatment cost associated with a relapse-free patient was the ratio between the total cost of DMTs and the number of relapse-free patients, treated and not treated, during the year of the study. RESULTS: A total of 158 patients with RRMS in 2016 and 183 in 2019 were included in our study. In 2016, 101 patients with RRMS (63.9%) received treatment with DMTs and 120 patients (75.9%) remained relapse-free. The mean cost of DMTs per patient in 2016 was €7414.3 (95% confidence interval [CI]: 6325.2-8503.4) considering all the patients (treated and not treated). In 2019, 126 patients (68.9%) received DMTs and 151 patients (82.5%) remained relapse-free. The mean cost of DMTs per patient in 2019 was €6985.4 (95% CI: 5986.9-7983.9) considering all the patients. The cost per year of DMTs to achieve a relapse-free patient was €9762.2 in 2016 and €8465.8 in 2019. CONCLUSIONS: The treatment cost per year to achieve a relapse-free patient was stable during successive measurements in the same population. Therefore, it may be considered a good real-world health indicator for patients with RRMS treated with DMTs.

Feasibility and Effects of Structured Physical Exercise Interventions in Adults with Relapsing-Remitting Multiple Sclerosis: A Pilot Study.

Multiple sclerosis (MS) is a chronic neurological disease which affects young adults at a time of maximum personal, professional and social growth. Recent guidelines on physical activity have established that exercise is an essential component of the clinical management of people with MS with mild or moderate degree of disability. The main purpose of this study was to test the feasibility and the effects of two different 40-week structured physical exercise interventions (a supervised high intensity interval training plus home exercise program and a self-applied home-based exercise program) on clinical evolution, psychological wellbeing, quality of life, fatigue, cardiorespiratory fitness, strength and balance of people with MS. Twenty-nine participants with relapsing-remitting MS (RRMS) participated in this study. All of them were fully ambulatory and with minimal disability (Expanded Disability Status Scale <3), for at least the last six months. Participants selected to be part of a combined face-to-face plus home exercise group (CFTFG; n = 8); a self-applied home-based exercise group (HG; n = 11) or a control group (CG; n = 10). A total of 23 participants completed the protocol (79.3%), of which 8 participants (100%) from the CFTFG, 7 (63.6%) from the HG and 8 (80%) from the CG. During the first 20-weeks of training, adherence from the CFTFG reached 77.5% and from the HG reached 50 %. During the second 20-weeks of training, adherence from the CFTFG reached 62.5% and from the HG reached 45.4%. After 20-weeks of training, a significant improvement in the absolute VO2 peak and in the 30-second sit to stand test was observed in the CFTFG (all p < .05). This study confirms that offering a 40-week structured exercise programme to a group of fully ambulatory and minimally disabled persons with RRMS is feasible and safe. Any adverse event related to the trial was reported by the participants.

The Cytotoxicity of Epsilon Toxin from Clostridium perfringens on Lymphocytes Is Mediated by MAL Protein Expression.

Epsilon toxin (Etx) from Clostridium perfringens is a pore-forming protein that crosses the blood-brain barrier, binds to myelin, and, hence, has been suggested to be a putative agent for the onset of multiple sclerosis, a demyelinating neuroinflammatory disease. Recently, myelin and lymphocyte (MAL) protein has been identified to be a key protein in the cytotoxic effect of Etx; however, the association of Etx with the immune system remains a central question. Here, we show that Etx selectively recognizes and kills only human cell lines expressing MAL protein through a direct Etx-MAL protein interaction. Experiments on lymphocytic cell lines revealed that MAL protein-expressing T cells, but not B cells, are sensitive to Etx and reveal that the toxin may be used as a molecular tool to distinguish subpopulations of lymphocytes. The overall results open the door to investigation of the role of Etx and Clostridium perfringens on inflammatory and autoimmune diseases like multiple sclerosis.

Functional outcome after primary endovascular therapy or IV thrombolysis alone for stroke. An observational, comparative effectiveness study.

BACKGROUND: Among the acute ischemic stroke patients with large vessel occlusions and contraindications for the use of IV thrombolysis, mainly on oral anticoagulation or presenting too late, primary endovascular therapy is often performed as an alternative to the standard therapy even though evidence supporting the use of endovascular reperfusion therapies is not yet established. Using different statistical approaches, we compared the functional independence rates at 3 months among patients undergoing primary endovascular therapy and patients treated only with IV thrombolysis. METHODS: We used data from a prospective, government-mandated and externally audited registry of reperfusion therapies for ischemic stroke (January 2011 to November 2012). Patients were selected if treated with either IV thrombolysis alone (n = 1,582) or primary endovascular thrombectomy (n = 250). A series of exclusions were made to homogenize the clinical characteristics among the two groups. We then carried out multivariate logistic regression and propensity score matching analyses on the final study sample (n = 1,179) to compare functional independence at 3 months, as measured by the modified Rankin scale scores 0-2, between the two groups. RESULTS: The unadjusted likelihood of good outcome was poorer among the endovascular group (OR: 0.69; 95% CI: 0.47-1.0). After adjustment, no differences by treatment modality were seen (OR: 1.51; 95% CI: 0.93-2.43 for primary endovascular therapy). Patients undergoing endovascular thrombectomy within 180-270 min (OR: 2.89; 95% CI: 1.17-7.15) and patients with severe strokes (OR: 1.84; 95% CI: 1.02-3.35) did better than their intravenous thrombolysis counterparts. The propensity score-matched analyses with and without adjustment by additional covariates showed that endovascular thrombectomy was as effective as intravenous thrombolysis alone in achieving functional independence (OR for unadjusted propensity score matched: 1.35; 95% CI: 0.9-2.02, OR for adjusted propensity score matched: 1.45; 95% CI: 0.91-2.32). CONCLUSION: This comparative effectiveness study shows that in ischemic stroke patients with contraindications for IV thrombolysis, primary endovascular treatment might be an alternative therapy at least as effective as IV thrombolysis alone. Randomized controlled trials are urgently needed.

Interferon-beta1b in multiple sclerosis: effect on progression of disability and clinical markers of treatment response.

There is limited long-term data on the effect of interferon-beta1b (IFN-beta1b) on disability progression in patients with multiple sclerosis (MS). There is also no reliable way of predicting individual responses to IFN-beta1b treatment. This prospective study investigated early clinical prognostic markers of disease activity and progression in 115 patients with relapsing-remitting MS (RRMS) treated with IFN-beta1b for almost 5 years. The study also compared progression of disability in IFN-beta1b-treated patients with a historic untreated cohort of MS patients (n = 44). The number of relapses in the first 2 years of MS and in the 2 years before treatment predicted an early relapse after IFN-beta1b treatment. The IFN-beta1b-treated group experienced a slower progression of disability than the untreated cohort, suggesting that IFN-beta1b treatment delays progression of disability in RRMS.

Direct and indirect costs of Multiple Sclerosis in Baix Llobregat (Catalonia, Spain), according to disability.

BACKGROUND: Multiple sclerosis (MS) is an incurable chronic disease that predominantly affects young adults. It has a high socio-economic impact which increases as disability progresses. An assessment of the real costs of MS may contribute to our knowledge of the disease and to treat it more efficiently. Our objective is to assess the direct and indirect costs of MS from a societal perspective, in patients monitored in our MS Unit (Baix Llobregat, Catalonia) and grouped according to their disability (EDSS). METHODS: We analysed data from 200 MS patients, who answered a questionnaire on resource consumption, employment and economical status. Mean age was 41.6 years, mean EDSS 2.7, 65.5% of patients were female, 79.5% had a relapsing-remitting course, and 67.5% of them were receiving immunomodulatory treatment (IT). Patients were grouped into five EDSS stages. Data from the questionnaires, hospital charts, Catalan Health Service tariffs, and figures from Catalan Institute of Statistics were used to calculate the direct and indirect costs. The cost-of-illness method, and the human capital approach for indirect costs, were applied. Sensitivity analyses were performed to strengthen results. RESULTS: The mean total annual cost of MS per patient results 24,272 euros. This cost varied according to EDSS: 14,327 euros (EDSS = 0), 18,837 euros (EDSS = 1-3), 27,870 euros (EDSS = 3.5-5.5), 41,198 euros (EDSS = 6-7) and 52,841 euros (EDSS>7.5). When the mean total annual costs was adjusted by the mean % of patients on IT in our Unit (31%) the result was 19589 euros. The key-drivers for direct costs were IT in low EDSS stages, and caregiver costs in high stages. Indirect costs were assessed in terms of the loss of productivity when patients stop working. Direct costs accounted for around 60% of total costs in all EDSS groups. IT accounts from 78% to 11% of direct costs, and decreased as disability progressed. CONCLUSION: The total mean social costs of MS in a cohort from Baix Llobregat (Catalonia) were estimated at 24,272 euros per patient/year, and ranged between 14,327 euros (EDSS = 0) and 52,841 euros (EDSS = 7.5-9.5). Total costs, and particularly informal and direct costs, increased as the disability progressed. IT should be able to delay the progression of disability to be efficient and not only effective.

Tau protein in cerebrospinal fluid: a possible marker of poor outcome in patients with early relapsing-remitting multiple sclerosis.

We analyzed the prognostic value of Tau protein, a marker of axonal damage, detected in the cerebrospinal fluid (CSF) of patients with relapsing-remitting multiple sclerosis (RRMS). We sampled the CSF from 32 patients with probable or definite RRMS, having had the disease for less than 5 years. We studied the relationship between Tau protein concentration in the CSF (CSF-TAU) and disability, time to next relapse and time to experience a one point increase on the Expanded Disability Status Scale (EDSS). CSF-TAU was correlated with the Progression Index at the end of follow-up. Patients with higher CSF-TAU experienced a more rapid one point increase in the EDSS. CSF-TAU was the only independent variable to predict the time to next relapse. CSF-TAU, as a marker of axonal loss, may help us to predict short-term outcome in patients with early RRMS.