Impact of COVID-19 on pregnancy and fetal outcomes in women with multiple sclerosis.

BACKGROUND: In the general population, maternal COVID-19 is associated with worse maternal and fetal outcomes. Two previous studies have assessed COVID-19 clinical outcomes in pregnant women with multiple sclerosis (MS), but there are no data about maternal and fetal outcomes. OBJECTIVES: In this multicenter study, we aimed to assess maternal and fetal outcomes in pregnant women with MS and COVID-19 infection. METHODS: We recruited pregnant patients with MS who contracted COVID-19 and were followed up in Italian and Turkish Centers, during 2020-2022. A control group was extracted from a previous Italian cohort. Associations between group (COVID-19 or healthy patients) and clinical outcomes (maternal complications, fetal malformations, and spontaneous abortion) were investigated with a weighted logistic regression where propensity score-based inverse probability of treatment weighting (IPTW) approach was applied for adjusting for difference in baseline confounders. RESULTS: In the multivariable analysis, COVID-19 during pregnancy was associated with a higher risk of maternal complications (odd ratio (OR) = 2.12; 95% confidence interval (CI) = 1.32-3.48; p = 0.002), while it was not associated with higher risk of spontaneous abortion and fetal malformations. CONCLUSION: Our data indicate that COVID-19 during pregnancy increases the risk of maternal complications, while it seems to have no significant impact on fetal outcomes.

Therapeutic choices and disease activity after 2 years of treatment with cladribine: An Italian multicenter study (CladStop).

BACKGROUND AND PURPOSE: Cladribine tablets, a purine analogue antimetabolite, offer a unique treatment regimen, involving short courses at the start of the first and second year, with no further treatment needed in years 3 and 4. However, comprehensive evidence regarding patient outcomes beyond the initial 24 months of cladribine treatment is limited. METHODS: This retrospective, multicenter study enrolled 204 patients with multiple sclerosis who had completed the 2-year course of cladribine treatment. The primary outcomes were therapeutic choices and clinical disease activity assessed by annualized relapse rate after the 2-year treatment course. RESULTS: A total of 204 patients were enrolled; most patients (75.4%) did not initiate new treatments in the 12 months postcladribine. The study found a significant reduction in annualized relapse rate at the 12-month follow-up after cladribine completion compared to the year prior to starting therapy (0.07 ± 0.25 vs. 0.82 ± 0.80, p < 0.001). Furthermore, patients with relapses during cladribine treatment were more likely to start new therapies, whereas older patients were less likely. The safety profile of cladribine was favorable, with lymphopenia being the primary registered adverse event. CONCLUSIONS: This study provides insights into therapeutic choices and disease activity following cladribine treatment. It highlights cladribine's effectiveness in reducing relapse rates and disability progression, reaffirming its favorable safety profile. Real-world data, aligned with previous reports, draw attention to ocrelizumab and natalizumab as common choices after cladribine. However, larger, prospective studies for validation and a more comprehensive understanding of cladribine's long-term impact are necessary.

Sars-CoV2 infection in pregnant women with multiple sclerosis.

BACKGROUND: In the general population, maternal SARS-CoV-2 infection during pregnancy is associated with worse maternal outcomes; however, only one study so far has evaluated COVID-19 clinical outcomes in pregnant and postpartum women with multiple sclerosis, showing no higher risk for poor COVID-19 outcomes in these patients. OBJECTIVE: In this multicenter study, we aimed to evaluate COVID-19 clinical outcomes in pregnant patients with multiple sclerosis. METHODS: We recruited 85 pregnant patients with multiple sclerosis who contracted COVID-19 after conception and were prospectively followed-up in Italian and Turkish Centers, in the period 2020-2022. A control group of 1354 women was extracted from the database of the Multiple Sclerosis and COVID-19 (MuSC-19). Univariate and subsequent logistic regression models were fitted to search for risk factors associated with severe COVID-19 course (at least one outcome among hospitalization, intensive care unit [ICU] admission and death). RESULTS: In the multivariable analysis, independent predictors of severe COVID-19 were age, body mass index ⩾ 30, treatment with anti-CD20 and recent use of methylprednisolone. Vaccination before infection was a protective factor. Vaccination before infection was a protective factor. Pregnancy was not a risk nor a protective factor for severe COVID-19 course. CONCLUSION: Our data show no significant increase of severe COVID-19 outcomes in patients with multiple sclerosis who contracted the infection during pregnancy.

COVID-19 vaccine hesitancy among Italian people with multiple sclerosis.

INTRODUCTION: Vaccine hesitancy promotes the spread of infectious diseases including COVID-19 virus, limiting the herd immunity. Complications caused by COVID-19 in people with multiple sclerosis forced governments to ensure them prior access to vaccinations. Their propensity to be vaccinated needs to be assessed to promote adhesion to vaccination programs. The aim of this study was to explore the COVID-19 vaccine hesitancy rate in pwMS. METHODS: We conducted an observational study recruiting patients affected by multiple sclerosis followed at MS Clinical and Research Unit of Tor Vergata University, Rome. We invited them to fill in an online survey about their intent to get COVID-19 vaccination. Fisher's exact test and Kruskal-Wallis test were performed to explore differences in sociodemographic, clinical, and emotional variables relative to the opinions about vaccinations. An exploratory factor analysis (EFA) was performed to assess the factorial structure of the questionnaire; Pearson's correlations between the factors and Big Five personality dimensions were also calculated. RESULTS: Of 276 respondents, 90% was willing to get vaccinated, while only 1.4% was sure to refuse the vaccination. Education level, opinions on safety and efficacy of vaccines, and emotional status were found to be associated to the propensity of getting the COVID-19 vaccination (respectively: p = 0.012, p < 0.001, and p = 0.0001). Moreover, general opinions on healthcare system were related to the intention to get vaccinated. CONCLUSION: Our results reinforce the importance of a good relationship between doctor and patient and the need to adapt doctors' communication strategy to patients' personalities and beliefs.

Exposure to natalizumab throughout pregnancy: effectiveness and safety in an Italian cohort of women with multiple sclerosis.

OBJECTIVE: Assessing the risk of clinical and radiological reactivation during pregnancy and post partum in women with multiple sclerosis (MS) treated with natalizumab (NTZ) throughout pregnancy (LONG_EXP) compared with women interrupting treatment before (NO_EXP) and within >-30 days and ≤90 days from conception (SHORT_EXP), and describing newborns' outcomes. METHODS: Maternal clinical and radiological outcomes and obstetric and fetal outcomes were retrospectively collected and compared among groups (NO_EXP, SHORT_EXP, LONG_EXP). Predictors of clinical and radiological reactivation were investigated through univariable and multivariable analysis. RESULTS: 170 eligible pregnancies from 163 women referring to 29 Italian MS centres were included. Annualised relapse rate (ARR) was significantly lower in LONG_EXP (n=66, 0.02 (0.001-0.09)) compared with NO_EXP (n=31, 0.43 (0.21-0.75), p=0.002) and SHORT_EXP (n=73, 0.46 (0.30-0.66), p=0.0004) during pregnancy, and in LONG_EXP (0.12 (0.05-0.24)) compared with SHORT_EXP (0.30 (0.17-0.50), p=0.008) during post partum. Gadolinium-enhancing (Gd+) lesions were less frequent in LONG_EXP (n=6/50, 2.00%) compared with NO_EXP (n=9/21, 42.86%) and SHORT_EXP after delivery (n=17/49, 34.69%, p=0.010).Delaying NTZ resumption after delivery significantly increased the risk of relapses (OR=1.29 (95% CI 1.07 to 1.57), p=0.009) and Gd+ lesions (OR=1.49 (95% CI 1.17 to 1.89, p=0.001). Newborns' weight, length, head circumference and gestational age did not differ among groups after adjusting for confounders. Anaemia was tracked in 4/69 LONG_EXP newborns. Congenital anomaly rate was within the expected range for the untreated MS population. CONCLUSIONS: Our findings indicate that in women with MS treated with NTZ before conception, continuation of NTZ throughout pregnancy and its early resumption after delivery mitigate the risk of clinical and radiological reactivation. This approach has no major impact on newborns' outcomes.

Switch from sequestering to anti-CD20 depleting treatment: disease activity outcomes during wash-out and in the first 6 months of ocrelizumab therapy.

OBJECTIVES: Switching between treatments is an opportunity for patients with multiple sclerosis (MS) to ameliorate disease control or safety. The aim of this study was to investigate the impact of switching from fingolimod (FTY) or natalizumab (NTZ) to ocrelizumab (OCR) on disease activity. METHODS: We retrospectively enrolled 165 patients treated with OCR from 11 MS centres. We assessed the association of demographic and clinical characteristics on relapse rate (RR) and activity on magnetic resonance imaging (MRI) during wash-out and after 6 months of treatment with OCR through univariable and multivariable negative binomial regression models. RESULTS: We registered a total of 35 relapses during the wash-out period. Previous treatment with FTY, relapses in the previous year, and relapsing-remitting course were associated with higher RR. In the first 6 months of OCR, 12 patients had clinical or MRI disease activity. Higher Expanded Disability Status Scale (EDSS) and higher lymphocyte count at OCR start were associated with a reduced probability of relapse. DISCUSSION AND CONCLUSION: This study confirms that withdrawal from sequestering agents as FTY increases the risk of relapses in the wash-out period. Nevertheless, starting OCR before achieving complete immune reconstitution could limit its effectiveness in the first 6 months probably because trapped lymphocytes escape the CD20-mediated depletion.

SARS-CoV-2 serology after COVID-19 in multiple sclerosis: An international cohort study.

BACKGROUND: The MuSC-19 project is an Italian cohort study open to international partners that collects data on multiple sclerosis (MS) patients with COVID-19. During the second wave of the pandemic, serological tests became routinely available. OBJECTIVE: To evaluate the seroprevalence of anti-SARS-CoV-2 antibodies according to the use of disease-modifying therapy (DMT) in a subset of patients included in the MuSC-19 data set who had undergone a serological test. METHODS: We evaluated the association between positive serological test results and time elapsed since infection onset, age, sex, Expanded Disability Status Scale score, comorbidities and DMT exposure using a multivariable logistic model. RESULTS: Data were collected from 423 patients (345 from Italy, 61 from Turkey and 17 from Brazil) with a serological test performed during follow-up. Overall, 325 out of 423 tested patients (76.8%) had a positive serological test. At multivariate analysis, therapy with anti-CD20 was significantly associated with a reduced probability of developing antibodies after COVID-19 (odds ratio (OR) = 0.20, p = 0.002). CONCLUSION: Patients with MS maintain the capacity to develop humoral immune response against SARS-COV-2, although to a lesser extent when treated with anti-CD20 drugs. Overall, our results are reassuring with respect to the possibility to achieve sufficient immunization with vaccination.

Patient's point of view on the use of telemedicine in multiple sclerosis: a web-based survey.

Restrictions in the access to healthcare facilities during COVID-19 pandemic have raised the need for remote monitoring of chronic medical conditions, including multiple sclerosis (MS). In order to enable the continuity of care in these circumstances, many telemedicine applications are currently tested. While physicians' preferences are commonly investigated, data regarding the patients' point of view are still lacking. We built a 37 items web-based survey exploring patients' propensity, awareness, and opinions on telemedicine with the aim to evaluate the sustainability of this approach in MS. Analysing 613 questionnaires out of 1093 that were sent to persons with MS followed at the Multiple Sclerosis Center of Tor Vergata University, Rome, we found that more than half of respondents (54%) were open to having a televisit. Propensity toward telemedicine significantly depended on having a higher income (p = 0.037), living farther from the center (p = 0.038), using computer and tablet (p = 0.010) and using the Internet for other remote activities (p < 0.001), conversely it was not influenced by any specific disease characteristics (i.e. degree of disability). The main advantages and disadvantages of televisit reported by participants were respectively saving time (70%) and impossibility to measure physical parameters (71%). Although the majority of respondents are in favour of televisit, so far this approach is restricted to those displaying better socioeconomic conditions and higher familiarity with technology. Implications of the study are that telemedicine platforms should be better tailored to patients' demands in order to spread the use of telemedicine, to enhance usability and to increase patients' adherence.

Defining the course of tumefactive multiple sclerosis: A large retrospective multicentre study.

BACKGROUND AND PURPOSE: Tumefactive multiple sclerosis (TuMS) (i.e., MS onset presenting with tumefactive demyelinating lesions [TDLs]) is a diagnostic and therapeutic challenge. We performed a multicentre retrospective study to describe the clinical characteristics and the prognostic factors of TuMS. METHODS: One hundred two TuMS patients were included in this retrospective study. Demographic, clinical, magnetic resonance imaging (MRI), laboratory data and treatment choices were collected. RESULTS: TuMS was found to affect women more than men (female:male: 2.4), with a young adulthood onset (median age: 29.5 years, range: 11-68 years, interquartile range [IQR]: 38 years). At onset, 52% of TuMS patients presented with the involvement of more than one functional system and 24.5% of them with multiple TDLs. TDLs most frequently presented with an infiltrative MRI pattern (38.7%). Cerebrospinal fluid immunoglobulin G oligoclonal bands were often demonstrated (76.6%). In 25.3% of the cases, more than one acute-phase treatment was administered, and almost one-half of the patients (46.6%) were treated with high-efficacy treatments. After a median follow-up of 2.3 years (range: 0.1-10.7 years, IQR: 3.4 years), the median Expanded Disability Status Scale (EDSS) score was 1.5 (range: 0-7, IQR: 2). Independent risk factors for reaching an EDSS score ≥3 were a higher age at onset (odds ratio [OR]: 1.08, 95% confidence interval [CI]: 1.03-1.14, p < 0.01), a higher number of TDLs (OR: 1.67, 95% CI: 1.02-2.74, p < 0.05) and the presence of infiltrative TDLs (OR: 3.34, 95% CI: 1.18-9.5, p < 0.001) at baseline. CONCLUSIONS: The management of TuMS might be challenging because of its peculiar characteristics. Large prospective studies could help to define the clinical characteristics and the best treatment algorithms for people with TuMS.

Validity of the Italian multiple sclerosis neuropsychological screening questionnaire.

The Multiple Sclerosis Neuropsychological Questionnaire (MSNQ) is a brief questionnaire useful for screening patients with multiple sclerosis (MS) at risk for cognitive impairment. It includes a patient self-assessment (MSNQ-p) and a section for the caregiver (informant) (MSNQ-i). This study's aim was to validate the Italian version of MSNQ and to compare MSNQ scores with Symbol Digit Modality Test (SDMT), Beck Depression Inventory (BDI), and Expanded Disability Status Scale (EDSS) score, measuring cognitive skills, mood status, and physical disability respectively. We enrolled 122 MS patients (and related caregivers) at MS center of Tor Vergata University Hospital of Rome. The final study sample consisted of 122 patients with MS (90 relapsing-remitting, 24 secondary progressive, and 8 primary progressive). Our results highlighted that MSNQ has a unidimensional factor structure. Correlational analyses found a good correlation between both versions (MSNQ-p and MSNQ-i) of the questionnaire. Both MSNQ-p and MSNQ-i were correlated with clinical variables, specifically with cognitive impairment, mood disorder, and with disability. The Italian version of MSNQ is reliable and useful as screening tool to identify MS patients at high risk of cognitive impairment.

Platelet-derived growth factor predicts prolonged relapse-free period in multiple sclerosis.

BACKGROUND: In the early phases of relapsing-remitting multiple sclerosis (RR-MS), a clear correlation between brain lesion load and clinical disability is often lacking, originating the so-called clinico-radiological paradox. Different factors may contribute to such discrepancy. In particular, synaptic plasticity may reduce the clinical expression of brain damage producing enduring enhancement of synaptic strength largely dependent on neurotrophin-induced protein synthesis. Cytokines released by the immune cells during acute inflammation can alter synaptic transmission and plasticity possibly influencing the clinical course of MS. In addition, immune cells may promote brain repair during the post-acute phases, by secreting different growth factors involved in neuronal and oligodendroglial cell survival. Platelet-derived growth factor (PDGF) is a neurotrophic factor that could be particularly involved in clinical recovery. Indeed, PDGF promotes long-term potentiation of synaptic activity in vitro and in MS and could therefore represent a key factor improving the clinical compensation of new brain lesions. The aim of the present study is to explore whether cerebrospinal fluid (CSF) PDGF concentrations at the time of diagnosis may influence the clinical course of RR-MS. METHODS: At the time of diagnosis, we measured in 100 consecutive early MS patients the CSF concentrations of PDGF, of the main pro- and anti-inflammatory cytokines, and of reliable markers of neuronal damage. Clinical and radiological parameters of disease activity were prospectively collected during follow-up. RESULTS: CSF PDGF levels were positively correlated with prolonged relapse-free survival. Radiological markers of disease activity, biochemical markers of neuronal damage, and clinical parameters of disease progression were instead not influenced by PDGF concentrations. Higher CSF PDGF levels were associated with an anti-inflammatory milieu within the central nervous system. CONCLUSIONS: Our results suggest that PDGF could promote a more prolonged relapse-free period during the course of RR-MS, without influencing inflammation reactivation and inflammation-driven neuronal damage and likely enhancing adaptive plasticity.

Abortion induces reactivation of inflammation in relapsing-remitting multiple sclerosis.

OBJECTIVE: To investigate clinical and radiological outcomes of women with relapsing-remitting multiple sclerosis (RRMS) undergoing abortion. METHODS: An independent, multicentre retrospective study was conducted collecting data from eight Italian MS centres. We compared the preconception and postabortion annualised relapse rate (ARR) and number of Gadolinium enhancing (Gd+) lesions, by analyses of covariance. Variables associated with postabortion clinical and MRI activity were investigated using Poisson regression models; each abortion was considered as a statistical unit. RESULTS: From 1995 to 2017, we observed 188 abortions (17 elective) in 153 women with RRMS. Abortions occurred after a mean time of 9.5 (4.4) weeks from estimated conception date. In 86 events out of 188, conception happened during treatment with disease modifying drugs. The mean postabortion ARR (0.63±0.74) was significantly increased (p=0.037) compared with the preconception year (0.50±0.71) as well as the postabortion mean number of new Gd+ lesions (0.77±1.40 vs 0.39±1.04; p=0.004). Higher likelihood of relapses was predicted by higher preconception ARR, discontinuation of preconception treatment and elective abortion; the occurrence of new Gd+ lesions was associated with higher preconception number of active lesions, discontinuation of preconception treatment, shorter length of pregnancy maintenance and elective abortion. CONCLUSIONS: Abortion was associated with clinical and radiological inflammatory rebound remarkably in the first 12 months postevent. Deregulated proinflammatory processes arising at the early stages of pregnancy might play a role both in MS reactivation and abortion. Women with MS should be counselled about these risks of abortion and followed up accordingly.

Executive functioning in relapsing-remitting multiple sclerosis patients without cognitive impairment: A task-switching protocol.

BACKGROUND: Cognitive dysfunction affects 40%-65% of multiple sclerosis (MS) patients, most often affecting information processing speed and working memory, mediated by the pre-frontal cortex (PFC). OBJECTIVE: Our study aimed to investigate PFC functioning through a task-switching protocol in relapsing-remitting multiple sclerosis (RRMS) patients without cognitive impairment. METHODS: A total of 24 RRMS patients and 25 controls were enrolled. Two different tasks were performed in rapid and random succession, so that the task was either changed from one trial to the next one (switch trials) or repeated (repetition trials). Switch trials are usually slower than repetitions, causing a so-called switch cost (SC). RESULTS: Patients had worse performance than controls only in the switch trials, as indicated by increased SC and reaction times. Moreover, patients showed a reduced ability to reconfigure the task-set for the execution of a new task and to disengage from the previous one. CONCLUSION: Our results showed a primary deficit in executive control processes involved in the task-switching performance in RRMS patients without cognitive impairment. This deficit may depend on the functional impairment of the PFC, which is essential to adjust behaviour rapidly and flexibly in response to environmental changes, representing one of the most sophisticated human abilities.

Cerebrospinal fluid lactate is associated with multiple sclerosis disease progression.

BACKGROUND: Altered cerebrospinal fluid (CSF) levels of lactate have been described in neurodegenerative diseases and related to mitochondrial dysfunction and neuronal degeneration. We investigated the relationship between CSF lactate levels, disease severity, and biomarkers associated with neuroaxonal damage in patients with multiple sclerosis (MS). METHODS: One-hundred eighteen subjects with relapsing-remitting multiple sclerosis (RRMS) were included, along with one-hundred fifty seven matched controls. CSF levels of lactate, tau protein, and neurofilament light were detected at the time of diagnosis. Patients were followed-up for a mean of 5 years. Progression index (PI), multiple sclerosis severity scale (MSSS), and Bayesian risk estimate for multiple sclerosis (BREMS) were assessed as clinical measures of disease severity and progression. Differences between groups and correlation between CSF lactate, disease severity and CSF biomarkers of neuronal damage were explored. RESULTS: CSF lactate was higher in RRMS patients compared to controls. A negative correlation was found between lactate levels and disease duration. Patients with higher CSF lactate concentration had significantly higher PI, MSSS, and BREMS scores at long-term follow-up. Furthermore, CSF lactate correlated positively and significantly with CSF levels of both tau protein and neurofilament light protein. CONCLUSIONS: Measurement of CSF lactate may be helpful, in conjunction with other biomarkers of tissue damage, as an early predictor of disease severity in RRMS patients. A better understanding of the alterations of mitochondrial metabolic pathways associated to RRMS severity may pave the way to new therapeutic targets to contrast axonal damage and disease severity.

Validity of the minimal assessment of cognitive function in multiple sclerosis (MACFIMS) in the Italian population.

Cognitive dysfunction involves 40-65 % of multiple sclerosis (MS) patients. It can be detected in all MS phenotypes from the early stages of the disease, and it tends to progress over time. Minimal Assessment of Cognitive Function in MS (MACFIMS) has been proved to be the most sensitive and comprehensive battery available for MS cognitive assessment in the English population. In Italy, MACFIMS applicability is limited in everyday clinical practice since the overall validity of this battery in the Italian MS population has never been demonstrated. The aim of this study was to translate/cross-culturally adapt and validate an Italian version of the MACFIMS. A total of 130 MS patients and 60 healthy controls (HCs) were enrolled and evaluated with an Italian version of the MACFIMS. All tests discriminated MS patients from HCs; according to the literature, approximately more than half of MS patients (70.8 %) exhibit cognitive impairment. Principal component analysis showed four distinct components: visual-spatial memory/processing speed, working memory, executive functions and verbal memory. Our study is the first to validate an Italian version of the MACFIMS. Several aspects of validity have been demonstrated: criterion and, partially, construct. Future work will investigate the longitudinal course of neuropsychological dysfunction in Italian MS patients using these measures.

Cortical ischemic lesion burden measured by DIR is related to carotid artery disease severity.

BACKGROUND: Over time, exposure to cerebrovascular risk factors and carotid artery disease may cause multiple asymptomatic brain cortical and subcortical microinfarcts, which are commonly found at brain autopsy. So far, lack of convenient neuroimaging tools limited the investigation of grey matter ischemic damage in vivo. We applied the Double Inversion Recovery (DIR) sequence to explore the impact of carotid artery disease on intracortical ischemic lesion load in vivo, taking into account the impact of demographic characteristics and vascular risk factors. METHODS: DIR was acquired in 62 patients with common cerebrovascular risk factors stratified in three groups according to carotid artery disease severity. Intracortical lesions scored on DIR (DIRlns) were classified by vascular territory, lobe and hemisphere. White matter hyperintensities (WMHs) volume was also quantified on Fluid Attenuated Inversion Recovery sequence (FLAIR). RESULTS: Among demographic characteristics and cerebrovascular risk variables explored, General Linear Model indicated that age and carotid artery disease were significantly associated to DIRlns. After correcting for age, DIRlns load was found to be significantly dependent on carotid artery stenosis severity (F(2, 58) = 5.56, p = 0.006). A linear positive correlation between DIRlns and WMHs was found after correcting for age (p = 0.003). CONCLUSIONS: Carotid disease severity is associated with DIRlns accrual. Microembolism and impaired cerebral hemodynamics may act as physiopathological mechanisms underlying cortical ischemic damage. The role of other factors, such as small vessel disease and the possible interaction with carotid disease, remains to be further explored.

Treatment modifiers across different regimens of natalizumab treatment in MS: An Italian real-world experience.

Despite its widespread use in clinical practice, the effectiveness of natalizumab extended interval dosing (EID) adopted from treatment start across different treatment intervals and individual modifiers (body mass index - BMI) is still under-investigated. Here, seven-hundred and forty-five multiple sclerosis (MS) patients, exposed to natalizumab for 3.30 â€‹± â€‹1.34 years, were retrospectively enrolled in an observational multicenter study. After stratifying patients in EID or standard interval dosing (SID), we assessed differences in time to relapse, MRI activity and Expanded Disability Status Scale (EDSS) progression. The primary analysis was conducted on patients exposed to EID interval from 5 weeks and 1 day to 7 weeks, while a secondary analysis included also EID periods up to 8 weeks. An additional analysis explored the impact of BMI. No differences in time to first relapse, time to radiological activity, time to EDSS progression or time to EDA (evidence of disease activity) were detected between SID and EID group (EID interval from 5 weeks to 1 day to 7 weeks). When including EID periods from 7 weeks and 1 day to 8 weeks, the EID group showed a trend towards higher risk of experience clinical relapses than the SID group. A higher EDA risk was also identified in EID patients with BMI above median. In conclusion, a higher risk of relapses seems to occur for EID above 7 weeks. Independently from the EID scheme adopted, higher BMI increases the risk of EDA in these patients.