Are we social enough? Use of social media among members of the Italian Society of Neurology for the study of dementia.

BACKGROUND: Clinical researchers increasingly embrace social media in their professional lives. The digital revolution has provided new routes for sharing data, disseminating results, and promoting the impact of scientific findings. In this study, we explored the attitude of the members of the Italian Society of Neurology for the study of dementia (SINdem) to use social media with the aim to set up possible corrective actions to maximize digitalization benefits at the individual and community levels. METHOD: An ad hoc designed survey was implemented and distributed to the SINdem and SINdem4Juniors communities. It explored the different use of social media taking into account frequency, type of social media use (active vs passive; professional vs private). Descriptive statistical analyses were performed alongside statistical comparisons to highlight possible differences in the use. RESULTS: We collected 133 answers showing a prominent use of social media in private life (t(132) = 21.1, p < 0.001), with SINdem4Juniors members showing a higher private use compared to the older SINdem colleagues. Professional use was mainly limited to passive activities such as following others' social profiles (t(132) = 11.9, p < 0.001). DISCUSSION: Overall scenario suggests that professional use of social media is very limited in both SINdem and SINdem4juniors communities. This evidence points to an urgent need for training interventions and top-down strategies aimed at improving collaboration, dissemination, and sharing through social media among individuals belonging to the same scientific-professional community.

ChatGPT vs. neurologists: a cross-sectional study investigating preference, satisfaction ratings and perceived empathy in responses among people living with multiple sclerosis.

BACKGROUND: ChatGPT is an open-source natural language processing software that replies to users' queries. We conducted a cross-sectional study to assess people living with Multiple Sclerosis' (PwMS) preferences, satisfaction, and empathy toward two alternate responses to four frequently-asked questions, one authored by a group of neurologists, the other by ChatGPT. METHODS: An online form was sent through digital communication platforms. PwMS were blind to the author of each response and were asked to express their preference for each alternate response to the four questions. The overall satisfaction was assessed using a Likert scale (1-5); the Consultation and Relational Empathy scale was employed to assess perceived empathy. RESULTS: We included 1133 PwMS (age, 45.26 ± 11.50 years; females, 68.49%). ChatGPT's responses showed significantly higher empathy scores (Coeff = 1.38; 95% CI = 0.65, 2.11; p > z < 0.01), when compared with neurologists' responses. No association was found between ChatGPT' responses and mean satisfaction (Coeff = 0.03; 95% CI = - 0.01, 0.07; p = 0.157). College graduate, when compared with high school education responder, had significantly lower likelihood to prefer ChatGPT response (IRR = 0.87; 95% CI = 0.79, 0.95; p < 0.01). CONCLUSIONS: ChatGPT-authored responses provided higher empathy than neurologists. Although AI holds potential, physicians should prepare to interact with increasingly digitized patients and guide them on responsible AI use. Future development should consider tailoring AIs' responses to individual characteristics. Within the progressive digitalization of the population, ChatGPT could emerge as a helpful support in healthcare management rather than an alternative.

A digital teleneuropsychology platform for the diagnosis of mild cognitive impairment: from concept to certification as a medical device.

BACKGROUND: Innovative digital solutions are shaping a new concept of dementia care, opening additional venues for prevention, diagnosis, monitoring and treatment. Hereby, we report the development of a tablet-based teleneuropsychology platform (Tenèpsia®), from concept to certification as Medical Device (MD) Class IIA, as per new MD regulation 745/2017. METHODS: The platform was designed for the remote cognitive evaluation and created thanks to the effort of a collaborative working group including experts from three Italian scientific societies and Biogen Italia S.r.l. (hereafter "Biogen"), and developers from Xenia Reply and Inside AI. The development strategy was guided by converting traditional paper-and-pencil tests into digital versions while maintaining comparable neuropsychological features and optimizing patient accessibility and user experience. The experts focused on the choice and adaptation of traditional neuropsychology measures for a 45-min teleneuropsychology assessment. RESULTS: The developers created a web and a mobile interface, respectively, for the professional (neuropsychologist) and non-professional (patient and caregiver) use. Recording of voice, drawing and typing information was enabled. Instant dashboards provide a quick overview of the patient's condition. Simulation activities were performed to obtain MD certification, valid across Europe. CONCLUSION: Neuropsychology services will benefit from the implementation in clinics of harmonized digital tools with adequate scientific and technological standards. The use of digital cognitive testing for the diagnosis of mild cognitive impairment is expected to enhance patient and clinician outcomes through simplified, digital objective data collection, sparing of time and resources, with a positive impact on healthcare costs and access to treatments, reducing inequalities and delays in diagnosis and cure.

Identifying definite patterns of unmet needs in patients with multiple sclerosis using unsupervised machine learning.

INTRODUCTION: People with multiple sclerosis (PwMS) exhibit a spectrum of needs that extend beyond solely disease-related determinants. Investigating unmet needs from the patient perspective may address daily difficulties and optimize care. Our aim was to identify patterns of unmet needs among PwMS and their determinants. METHODS: We conducted a cross-sectional multicentre study. Data were collected through an anonymous, self-administered online form. To cluster PwMS according to their main unmet needs, we performed agglomerative hierarchical clustering algorithm. Principal component analysis (PCA) was applied to visualize cluster distribution. Pairwise comparisons were used to evaluate demographics and clinical distribution among clusters. RESULTS: Out of 1764 mailed questionnaires, we received 690 responses. Access to primary care was the main contributor to the overall unmet need burden. Four patterns were identified: cluster C1, 'information-seekers with few unmet needs'; cluster C2, 'high unmet needs'; cluster C3, 'socially and assistance-dependent'; cluster C4, 'self-sufficient with few unmet needs'. PCA identified two main components in determining the patterns: the 'public sphere' (access to information and care) and the 'private sphere' (need for assistance and social life). Older age, lower education, longer disease duration and higher disability characterized clusters with more unmet needs in the private sphere. However, demographic and clinical factors failed in explaining the four identified patterns. CONCLUSION: Our study identified four unmet need patterns among PwMS, emphasizing the importance of personalized care. While clinical and demographic factors provide some insight, additional variables warrant further investigation to fully understand unmet needs in PwMS.

Cost-Analysis of Telemedicine Interventions Compared with Traditional Care in the Management of Chronic Neurological Diseases: A Systematic Review.

Background: Telemedicine has proven successful in relieving the burden of chronic neurological disorders from the national health care systems by ensuring a highly customized and effective management plan. Although many studies focus on assessing telemedicine effectiveness, little is known about the economic implications of telemedicine applications in chronic neurological diseases (CNDs). This issue could account for a lack of widespread implementation. Objective: Our study attempted to fill this gap by systematically reviewing scientific literature on the economic evaluation of telemedicine compared with traditional care in the management of CNDs. Methods: We performed a literature search on PubMed, Google Scholar, Scopus, Embase, and Medline. The inclusion criteria were as follows: (1) studies with a full cost-analysis; (2) randomized controlled trials; (3) studies comparing telemedicine interventions with traditional care; (4) articles focusing only on CNDs. Conversely, the exclusion criteria were as follows: (1) studies focusing on acute neurological conditions or other diseases and (2) study protocols, case report, duplicate articles, abstract only, books, letters to editors, and review articles. Results: Ten articles met the inclusion criteria. Three different approaches of telemedicine intervention could be identified: digital cognitive-behavioral therapy (CBT), motor telerehabilitation, and home monitoring and assessment devices. Conclusion: Cost-analysis showed an overall benefit in terms of both cost and effectiveness from the application of telemedicine instead of in-presence management in CNDs. Among the identified interventions, digital CBT proved to be the most cost-saving. However, promising results were also found in monitoring and assessment devices and in telerehabilitation. Definitely, however, more thorough, comprehensive, and high-quality economic evaluation studies are needed.

Validation of the swallowing disturbance questionnaire in people with multiple sclerosis.

BACKGROUND: The DYSPHAGIA IN MULTIPLE SCLEROSIS (DYMUS) questionnaire is the only specific tool developed to screen for dysphagia in people with Multiple Sclerosis (pwMS). However, some limitations of DYMUS could potentially be addressed by the SWALLOWING DISTURBANCE QUESTIONNAIRE (SDQ), which has not yet been validated in pwMS. The objective of this study was to translate and validate the SDQ into the Italian language for use in pwMS to detect swallowing disturbances. METHODS: We translated the SDQ into Italian and adapted it for use in Italian pwMS. PwMS aged > 18 years, assessed for disability using the Expanded Disability Status Scale (EDSS), completed the SDQ and DYMUS questionnaires and performed the 3-OUNCE WATER SWALLOW TEST (WST). Clinical and demographic data were collected for each patient. The Italian version of the SDQ was retested after 30 days. RESULTS: A total of 84 pwMS were recruited for the study, consisting of 73.8 % women and 48.8 % with a relapsing-remitting form of MS. The mean age of participants was 44.5 years (SD: ±12.46), with a mean disease duration of 17 years (SD: ±10.27), and a median EDSS of 4 (range 1.5-7.5). The Cronbach's alpha for SDQ (to assess internal consistency) was 0.902, which increased to 0.908 after the elimination of item 15, resulting in the SDQ composed of 14 items. ROC analysis demonstrated good accuracy of the 14-item SDQ in pwMS (AUC: 0.811). By dividing the 14-item SDQ score into quartiles, three risk levels for dysphagia were identified: low (score 1-3), intermediate (score 4-8), and high (score ≥9). 14-item SDQ scores significantly correlated with DYMUS (r = 0.820; p<0.0001) and with EDSS (r = 0.541; p<0.0001). PwMS who reported dysphagia had a significantly higher mean 14-item SDQ score (8.27 ± SD 8.15) compared to those without swallowing problems (2.77 ± SD 4.25; p = 0.003). Additionally, pwMS with a positive WST had a significantly higher mean 14-item SDQ score (10.17 ± SD 8.96) than those with a negative WST (2.96 ± SD 3.93; p = 0.02). The Intraclass Correlation Coefficient for the retest, calculated on 48 pwMS in a stable phase of the disease, was 0.91 (95 % CI 0.84-0.95). CONCLUSION: The 14-item SDQ has demonstrated high internal consistency, good accuracy, and reliability in pwMS, making it a readily applicable tool for investigating dysphagia in MS.

Apparently isolated CNS involvement in Erdheim-Chester disease: Case report.

We present the case of a 48-year-old-woman with apparently isolated central nervous system Erdheim-Chester disease characterized by brainstem involvement. Erdheim-Chester disease is extremely rare and multisystem impairment should always be sought in the suspicion of such pathology.

Repetitive Transcranial Magnetic Stimulation (rTMS) in Mild Cognitive Impairment: Effects on Cognitive Functions-A Systematic Review.

Repetitive transcranial magnetic stimulation (rTMS) is a non-invasive brain stimulation technique also used as a non-pharmacological intervention against cognitive impairment. The purpose of the present review was to summarize what is currently known about the effectiveness of rTMS intervention on different cognitive domains in patients with mild cognitive impairment (MCI) and to address potential neuromodulation approaches in combination with electroencephalography (EEG) and neuroimaging, especially functional magnetic resonance imaging (fMRI). In this systematic review, we consulted three main databases (PubMed, Science Direct, and Scopus), and Google Scholar was selected for the gray literature search. The PRISMA flowchart drove the studies' inclusion. The selection process ensured that only high-quality studies were included; after removing duplicate papers, explicit ratings were given based on the quality classification as high (A), moderate (B), or low (C), considering factors such as risks of bias, inaccuracies, inconsistencies, lack of direction, and publication bias. Seven full-text articles fulfilled the stated inclusion, reporting five double-blind, randomized, sham-controlled studies, a case study, and a randomized crossover trial. The results of the reviewed studies suggested that rTMS in MCI patients is safe and effective for enhancing cognitive functions, thus making it a potential therapeutic approach for MCI patients. Changes in functional connectivity within the default mode network (DMN) after targeted rTMS could represent a valuable indicator of treatment response. Finally, high-frequency rTMS over the dorsolateral prefrontal cortex (DLPFC) has been shown to significantly enhance cognitive functions, such as executive performance, together with the increase of functional connectivity within frontoparietal networks. The main limitations were the number of included studies and the exclusion of studies using intermittent theta-burst stimulation, used in studies on Alzheimer's disease. Therefore, neuroimaging techniques in combination with rTMS have been shown to be useful for future network-based, fMRI-guided therapeutic approaches.

Google Maps Timeline: An open-access digital tool to monitor walking abilities in people with multiple sclerosis.

Introduction: Gait impairment is common in multiple sclerosis (MS), but difficult to evaluate in clinical practice. In this proof-of-concept observational study, we compared walking ability recorded by Google Maps Timeline to conventional clinical measures in people with MS. Methods: We used open-access Google Maps Timeline to record the total number of days with walking activity, walking distance, walking time, and walking speed. Each Google Maps Timeline variable was included in a different stepwise linear regression model including all conventional clinical variables. Results: We included nine people with MS (age 43.1 ± 6.6 years; females 55.6%; disease duration 12.7 ± 3.1 years; median Expanded Disability Status Scale 3.0 (range 1.0-5.5)). Higher percentage of days with recorded walking was associated with lower Fatigue Severity Scale (p = 0.01), and higher MS Walking Scale (p = 0.04). Longer average daily walking distance was associated with shorter Timed-25 Foot Walking Test (p = 0.02), lower Expanded Disability Status Scale (p = 0.01), and higher Euro-Quality of Life (p = 0.04). Longer average daily walking time was associated with shorter Timed-25 Foot Walking Test (p = 0.03). Higher walking speed was associated with lower Fatigue Severity Scale (p = 0.04). Conclusion: Google Maps Timeline parameters provide actual estimates of daily walking activities in MS.

Multiple Sclerosis: Diagnosis, Management, and Future Opportunities.

Multiple sclerosis (MS) is one of the most common inflammatory neurological diseases which leads to a highly heterogeneous set of symptoms and signs due to the differential involvement of the motor, sensory, visual, and autonomic systems [...].

Cognitive, behavioral, and brain functional connectivity correlates of fatigue in amyotrophic lateral sclerosis.

INTRODUCTION: Fatigue is defined as a symptom of exhaustion unexplained by drug effects or psychiatric disorders and comprises two main components (i.e., central or "mental" and peripheral or "physical" components), both influencing global disability in amyotrophic lateral sclerosis (ALS). We aim at investigating the clinical correlations between "physical" and "mental" components of fatigue, measured by the Multidimensional Fatigue Inventory scale, and motor and cognitive/behavioral disability in a large sample of patients with ALS. We also investigated the correlations between these measures of fatigue and resting-state functional connectivity of brain functional magnetic resonance imaging (RS-fMRI) large-scale networks in a subset of patients. METHODS: One hundred and thirty ALS patients were assessed for motor disability, cognitive and behavioral dysfunctions, fatigue, anxiety, apathy, and daytime sleepiness. Moreover, the collected clinical parameters were correlated with RS-fMRI functional connectivity changes in the large-scale brain networks of 30 ALS patients who underwent MRI. RESULTS: Multivariate correlation analysis revealed that "physical" fatigue was related to anxiety and respiratory dysfunction, while "mental" fatigue was related to memory impairment and apathy. Moreover, the mental fatigue score was directly related to functional connectivity in the right and left insula (within the salience network), and inversely related to functional connectivity in the left middle temporal gyrus (within the default mode network). CONCLUSIONS: Although the "physical" component of fatigue may be influenced by the disease itself, in ALS the "mental" component of fatigue correlates with cognitive and behavioral impairment, as well as with alterations of functional connectivity in extra-motor networks.

Health related quality of life in the domain of physical activity predicts confirmed disability progression in people with relapsing remitting multiple sclerosis.

INTRODUCTION: The diagnosis of the progression phase of Multiple Sclerosis (MS) is still retrospective and based on the objectivation of clinical disability accumulation. OBJECTIVES: To assess whether the Patient Reported Outcomes Measures (PROMs) scores predict the occurrence of disease progression within three years of follow-up. METHODS: Observational prospective multicenter study. Stable Relapsing-Remitting MS (RRMS) patients were enrolled. At enrollment, patients completed the following PROMs: Beck Depression Inventory- II, The Treatment Satisfaction Questionnaire for Medications, Medical Outcomes Study Short Form 36- Item (SF36), Fatigue Severity Scale. EDSS was assessed at enrollment and three years later. The outcome measure was defined as the occurrence of confirmed disability progression (CDP) within three years of follow-up. Univariable and multivariable logistic regression models were performed to study the association between the final score of each test and the outcome. RESULTS: SF36-Physical Functioning (SF36-PF) was the only independent variable associated with the outcome. The ROC curve analysis determined a score of 77.5 at SF36-PF as the cut-off point identifying patients experiencing CDP within three years of follow-up [AUC: 0.66 (95% CI: 0.56-0.75)]. CONCLUSIONS: RRMS patients scoring higher (>77.5) at SF36-PF subscale have a higher likelihood to experience CDP within the next three years.

Previous disease-modifying treatments influence T lymphocyte kinetics in people with multiple sclerosis switching to ocrelizumab.

BACKGROUND: Recently, concern has been raised about the influence of the previous disease-modifying treatments (DMTs) on the clinical efficacy of ocrelizumab (OCR). We aimed to evaluate whether the previous DMT affects the lymphocyte subset kinetics in people with Multiple Sclerosis (MS) switching to OCR. METHODS: This is a multicenter, retrospective, real-world study on consecutive MS patients who started or switched to OCR. We grouped them by prior DMT in: (i) naïve-to-treatment (NTT), (ii) switching from fingolimod (SF) and (iii) switching from natalizumab (SN). Differences in absolute lymphocyte count and lymphocyte subset count changes, considering the period from baseline to 6 months, over all the three groups were assessed with an inverse-probability-weighted regression adjustment model. RESULTS: Mean T CD4+ cell count reduction from baseline to the six-month follow-up was more pronounced in the SN group compared to the NTT (p = 0,026). Further, patients in the SF group experienced a less pronounced CD4 T cell number decrease than both NTT and SN groups (p = 0,04 and p < 0,001, respectively). Patients in the SF group experienced an increase in CD8 T cell absolute number, whereas those in the NTT and SN groups experienced a significant decrease (p = 0,015 and p < 0,001, respectively). Patients experiencing early inflammatory activity showed a lower CD8+ cell count at baseline than stable patients (p = 0,02). CONCLUSIONS: Previous DMTs influence the lymphocyte kinetics in people with MS switching to OCR. Reassessment of these findings over a larger population may help optimize the switch.

Sexual Dysfunction in People with Multiple Sclerosis: The Role of Disease Severity, Illness Perception, and Depression.

Despite being a common issue in people with multiple sclerosis (pwMS), sexual dysfunction is still underinvestigated. This work aims to assess the potential determinants of sexual dysfunction in pwMS by considering its relationship with disease severity (in terms of global disability), illness perception, and depressive symptoms. In this multicenter study, 1010 pwMS responded to an online survey. A serial mediation model considering negative illness perception and depressive symptoms as mediators of the relationship between disease severity and sexual dysfunction was conducted using the SPSS PROCESS Macro with bias-corrected bootstrapping (5000 samples). Disease severity exerts an indirect effect on sexual dysfunction via illness perception, both independently and through depressive symptoms. However, the results indicated that illness perception plays a more crucial role in sexual dysfunction in pwMS with mild disability than in pwMS with moderate-severe disability. This study suggests that higher disability increases its magnitude by enhancing negative illness perception, that, in turn, affects sexual dysfunction both directly and through depressive symptoms, especially in pwMS with mild disability. Modulating the effect of illness perception by favoring adaptive coping strategies might represent a valid approach to mitigate sexual dysfunction symptoms in MS.

Clinically Manifest Infections Do Not Increase the Relapse Risk in People with Multiple Sclerosis Treated with Disease-Modifying Therapies: A Prospective Study.

BACKGROUND: Many factors are believed to be positively associated with the incidence of relapses in people with multiple sclerosis (MS), including infections. However, their role is still controversial. We aimed to investigate whether symptomatic infections in people with MS increase the risk of relapse in the short, medium, or long term. MATERIALS AND METHODS: We enrolled consecutive patients with relapsing MS (RMS) from October to December 2018. From enrolment up to September 2020, an online questionnaire investigating the occurrence of infections was sent via WhatsApp® monthly to the enrolled patients, while in-person visits were performed every six months. When patients complained of symptoms compatible with relapses, they attended an extra in-person visit. RESULTS: We enrolled 155 patients with RMS, and 88.38% of patients were treated with disease-modifying therapies. In the dataset, 126,381 total patient days, 78 relapses, and 1202 infections were recorded over a period of about 2 years. No increased risk of relapse after clinically manifest infections was found in the short-, medium-, or long-term period. No correlation was found between all infections and the number of relapses (p = 0.212). The main analyses were repeated considering only those infections that had at least two of the following characteristics: duration of infection ≥ 4 days, body temperature > 37° Celsius, and the use of drugs (antibiotics and/or antivirals), and no significant associations were observed. CONCLUSIONS: No associations between infections and relapses were observed, likely suggesting that disease-modifying therapies may protect against the risk of relapse potentially triggered by infections.

Psychometric Calibration of a Tool Based on 360 Degree Videos for the Assessment of Executive Functions.

INTRODUCTION: Over the last decades, interactive technologies appeared a promising solution in the ecological evaluation of executive functioning. We have developed the EXecutive-functions Innovative Tool 360° (EXIT 360°), a new instrument that exploits 360° technologies to provide an ecologically valid assessment of executive functioning. AIM: This work wanted to evaluate the convergent validity of the EXIT 360°, comparing it with traditional neuropsychological tests (NPS) for executive functioning. METHODS: Seventy-seven healthy subjects underwent an evaluation that involved: (1) a paper-and-pencil neuropsychological assessment, (2) an EXIT 360° session, involving seven subtasks delivered by VR headset, and (3) a usability assessment. To evaluate convergent validity, statistical correlation analyses were performed between NPS and EXIT 360° scores. RESULTS: The data showed that participants had completed the whole task in about 8 min, with 88.3% obtaining a high total score (≥12). Regarding convergent validity, the data revealed a significant correlation between the EXIT 360° total score and all NPS. Furthermore, data showed a correlation between the EXIT 360° total reaction time and timed neuropsychological tests. Finally, the usability assessment showed a good score. CONCLUSION: This work appears as a first validation step towards considering the EXIT 360° as a standardized instrument that uses 360° technologies to conduct an ecologically valid assessment of executive functioning. Further studies will be necessary to evaluate the effectiveness of the EXIT 360° in discriminating between healthy control subjects and patients with executive dysfunctions.

Immunomodulatory effects of ocrelizumab and candidate biomarkers for monitoring treatment response in multiple sclerosis.

Ocrelizumab is a humanized monoclonal antibody designed to bind to the CD20 molecule, resulting in a rapid depletion of B-cells; however, it has been shown that lymphocyte subpopulations other than B-cells are affected by the drug. To review the effects of ocrelizumab on circulating lymphocytes and identify candidate biomarkers to predict and monitor treatment response. A literature search for the most relevant articles from 2006 to 2022 was conducted in PubMed and Scopus. The effect of ocrelizumab on the peripheral immune system goes beyond B-cells; it also depletes T CD20 + lymphocytes. Further, ocrelizumab reshapes the T-cell response toward a low inflammatory profile and induces an increase in T CD8 + regulatory cell percentage. A higher Body Mass Index and higher B-cell count at baseline have been associated with early B-cell reappearance. Serum neurofilament light chain reduction has been associated with treatment response. Ocrelizumab treatment exerts a broad immunomodulatory effect and may be tailored based on patients' clinical and biological profiles.

Association of vitamin D serum levels and vitamin D supplementation with B cell kinetics and disease activity in Multiple Sclerosis patients treated with ocrelizumab: an Italian multi-center study.

BACKGROUND: Several observational studies have shown an association between low circulating levels of 25-hydroxy- vitamin D (25(OH)D) and an increase in inflammatory activity in Multiple Sclerosis (MS). Among its immunomodulatory functions, 25(OH)D suppresses proliferation and immunoglobulin production of B cells. 25(OH)D supplementation has been associated with better radiological outcomes in MS patients treated with interferon (IFN)-B, glatiramer acetate, fingolimod, natalizumab and rituximab. Our study is aimed at analyzing the association of 25(OH)D serum levels and supplementation with B cell kinetics and clinical-radiological outcomes of people with MS treated with ocrelizumab. METHODS: We have retrospectively collected clinical and radiological data from 136 MS patients who have been treated with ocrelizumab, have undergone at least two treatment cycles and for whom data on serum 25(OH)D levels and intake were available. The patients were divided into three groups according to baseline 25(OH)D serum levels: deficient (≤19,9 ng/ml), insufficient (20-29,9 ng/ml), and normal range 25(OH)D (>30 ng/ml). According to 25(OH)D intake, we divided our population into users and non-users. To explore B cell kinetics at six- and twelve-month follow-ups, the patients were divided into two groups: with fast repopulation (FR) and slow repopulation rate (SR), based on the reappearance or non- appearance of CD19 at each time point. RESULTS: When considering the entire population, the mean 25(OH)D serum level (sd) was 26.27 ng/ml (14.15). 43 (31,62%) patients were classified as deficient, 52 (38,24%) were classified as insufficient, and 41 (30,14%) showed 25(OH)D serum levels within the normal range. 60.29% (82/136) of the patients were classified as users, and 39.70% (54/136) as non-users. Over the eighteen-month treatment period, we observed a significant difference between the 25(OH)D users and the non-users as concerns the number of scans with at least one new/enlarging T2 lesion (2% vs 15.38%, respectively; p= 0.025). In the multinomial regression model, 25(OH)D deficiency (serum levels ≤19,9 ng/ml) was significantly associated with a higher likelihood of disease activity during a follow-up of eighteen months (p = 0.029, RRR = 4.84, Confidence Interval (CI) 1.17 - 20.01). After six months, there were 30/136 FR patients (22,05%), whereas only 22/136 (16,17%) showed early B cell reappearance at twelve month follow up. 86.66% of the patients in the FR group showed 25(OH)D levels lower than 30 ng/ml (25(OH)D deficiency or insufficiency), whereas only 65.09% of the SR patients presented vitamin D levels lower than 30 ng/ml (p= 0.024). In the logistic regression model, 25(OH)D serum levels below 30 ng/ml were associated with a higher likelihood of early B cell reappearance at six month follow up (p= 0.042). CONCLUSIONS: 25(OH)D supplementation and serum levels might be associated with B cell kinetics and radiological activity of patients with MS treated with ocrelizumab.