Neuromyelitis optica spectrum disorders with and without associated autoimmune diseases.

OBJECTIVES: We aimed to determinate the frequency of this association and compare the features of neuromyelitis optica spectrum disorder (NMOSD) with and without associated autoimmune diseases (AD) in a Latin American (LATAM) population in clinical practice. METHODS: We retrospectively reviewed the medical records of patients with NMOSD according to the 2015 diagnostic criteria. Patients from Argentina (n=77), Brazil (n=46), and Venezuela (n=17) were enrolled and classified into two groups as follows: with AD or without AD. Clinical, paraclinical (including aquaporin-4 antibodies (AQP4-ab) status), magnetic resonance imaging (MRI), and prognosis data were analyzed and compared. Kaplan-Meier (KM) and the Nelson-Aalen estimator analyses were performed to estimate both time and the cumulative hazard risk of disability reaching an EDSS≥4; and time for the first recurrence. RESULTS: Out of 140 patients, 33 (23.5%) patients had associated an AD at presentation. The most frequent associated AD was Hashimoto disease (n=10) followed by lupus (n=7) and Sjogren's syndrome (n=6). However, rituximab use (42.4% vs. 21.5%, p=0.02), female gender (82.2% vs. 100%, p=0.006), corticospinal lesions on MRI (0% vs. 12.5%, p=0.01) at onset, and positivity for antinuclear antibodies (21.2% vs. 48.4%, p=0.03) were significantly associated with NMOSD patients with AD in comparison to NMOSD patients without AD. No differences were found in other clinical and paraclinical aspects between groups. KM and Nelson-Aalen estimator analyses did not show differences between groups. CONCLUSION: NMOSD patients associated with AD were observed in 23.5%. In addition, NMOSD patients with and without associated AD were similar in most evaluated features.

Disability outcomes in NMOSD and MOGAD patients: data from a nationwide registry in Argentina.

The objective was to evaluate time to reach an EDSS of 4, 6, and 7 in NMOSD and MOGAD patients included in the Argentinean MS and NMOSD registry (RelevarEM, NCT 03,375,177). METHODS: NMOSD patients diagnosed according to 2015 criteria and with MOGAD were identified. Patients with at least 3 years of follow-up and periodic clinical evaluations with EDSS outcomes were included. AQP4-antibody and MOG-antibody status was recorded, and patients were stratified as seropositive and seronegative for AQP4-antibody. EDSS of 4, 6, and 7 were defined as dependent variables. Log rank test was used to identify differences between groups. RESULTS: Registry data was provided for a total of 137 patients. Of these, seventy-five presented AQP4-ab-positive NMOSD, 45 AQP4-ab-negative NMOSD, and 11 MOGAD. AQP4-ab status was determined by cell-based assay (CBA) in 72% of NMOSD patients. MOG-ab status was tested by CBA in all cases. Mean time to EDSS of 4 was 53.6 ± 24.5 vs. 63.1 ± 32.2 vs. 44.7 ± 32 months in seropositive, seronegative NMOSD, and MOGAD, respectively (p = 0.76). Mean time to EDSS of 6 was 79.2 ± 44.3 vs. 75.7 ± 48.6 vs. 54.7 ± 50 months in seropositive, seronegative NMOSD, and MOGAD (p = 0.23), while mean time to EDSS of 7 was 86.8 ± 54 vs. 80.4 ± 51 vs. 58.5 ± 47 months in seropositive, seronegative NMOSD, and MOGAD (p = 0.39). CONCLUSION: No differences were observed between NMOSD (seropositive and seronegative) and MOGAD in survival curves.

Chiasmatic lesions on conventional magnetic resonance imaging during the first event of optic neuritis in patients with neuromyelitis optica spectrum disorder and myelin oligodendrocyte glycoprotein-associated disease in a Latin American cohort.

BACKGROUND AND PURPOSE: Optic neuritis (ON) is often the initial symptom of neuromyelitis optica spectrum disorder (NMOSD) and myelin oligodendrocyte glycoprotein-associated disease (MOGAD). We aimed to compare the frequency and pattern of chiasmatic lesions in MOGAD-related ON (MOGAD-ON) and NMOSD-related ON (NMOSD-ON) using conventional brain imaging (magnetic resonance imaging [MRI]) in Latin America (LATAM). METHODS: We reviewed the medical records and brain MRI (≤30 days from ON onset) of patients with a first event of MOGAD-ON and NMOSD-ON. Patients from Argentina (n = 72), Chile (n = 21), Ecuador (n = 31), Brazil (n = 30), Venezuela (n = 10) and Mexico (n = 82) were included. Antibody status was tested using a cell-based assay. Demographic, clinical, imaging and prognostic (as measured by the Visual Functional System Score [VFSS] of the Expanded Disability Status Scale) data were compared. RESULTS: A total of 246 patients (208 NMOSD and 38 MOGAD) were included. No differences were found in gender and ethnicity between the groups. We observed chiasmatic lesions in 66/208 (31.7%) NMOSD-ON and in 5/38 (13.1%) MOGAD-ON patients (p = 0.01). Of these patients with chiasmatic lesions, 54/66 (81.8%) and 4/5 had associated longitudinally extensive optic nerve lesions, 45/66 (68%) and 4/5 had bilateral lesions, and 31/66 (47%) and 4/5 showed gadolinium-enhancing chiasmatic lesions, respectively. A positive correlation was observed between VFSS and presence of bilateral (r = 0,28, p < 0.0001), chiasmatic (r = 0.27, p = 0.0001) and longitudinally extensive lesions (r = 0,25, p = 0.0009) in the NMOSD-ON group, but no correlations were observed in the MOGAD-ON group. CONCLUSIONS: Chiasmatic lesions were significantly more common in NMOSD than in MOGAD during an ON attack in this LATAM cohort. Further studies are needed to assess the generalizability of these results.

Diagnostic uncertainty during the transition to secondary progressive multiple sclerosis: Multicenter study in Argentina.

BACKGROUND: A period of diagnostic uncertainty often characterizes the clinical transition from relapsing to secondary progressive multiple sclerosis (SPMS). OBJECTIVE: The aim of this study was to describe the length of time required to reclassify relapsing-remitting MS (RRMS) patients who have clinically transitioned to SPMS (diagnosis uncertainty). METHODS: This is a retrospective multicenter cohort study conducted in Argentina, identifying in every center all patients with diagnosis of MS who transitioned from RRMS to SPMS during the follow-up. We identified the dates of the last definitive RRMS and first definitive SPMS diagnoses for diagnostic uncertainty. The time required to reclassify RRMS who transitioned to SPMS and the time from disease onset to reclassify SPMS were calculated using the Kaplan-Meier method. RESULTS: A total of 170 patients were included, where the mean age at disease onset (first symptom) was 36 ± 6 years; the length of time required to reclassify RRMS patients who transitioned to SPMS was 3.3 ± 1.1 years (range = 1-7 years); and the time from disease onset to classify SPMS was 19.4 ± 8.5 years (range = 16-35 years). CONCLUSION: A period of diagnostic uncertainty regarding the transition from RRMS to SPMS was present in many of our patients, with a mean time of 3.3 years.

Long-term outcomes of symptomatic and asymptomatic patients undergoing carotid endarterectomy in an average-volume community hospital.

BACKGROUND: Long-term benefit of carotid endarectomy has not yet been fully investigated in average volume centers. Thus our purpose is to evaluate long-term results of carotid endarterectomies at a medium-volume hospital. METHODS: A retrospective analysis of carotid artery stenosis operated between 2008 and 2017 in a community hospital was done. Demographic and postoperative outcomes were evaluated in short and long-term by Kaplan-Meier survival analysis. RESULTS: 167 procedures in 159 patients were included. Average age was 72 years, and 65% were men. Twenty-nine percent of the patients were symptomatic and the rest asymptomatic. Median hospitalization was 3 (IQR 3-4) days and the mean follow-up was 56 months. No hospital mortality was recorded. At 120-month follow-up, freedom of stroke was 97.4%, death 97.3%, restenosis, 98.7% and all combined events 92.9% (log rank p = .042) Combined event-free survival was 84.4% in symptomatic patients, and 96.1% in asymptomatic patients (log rank p = .025). CONCLUSIONS: In a medium-volume hospital combined event-free survival was 84.4% in symptomatic patients and 96.1% in asymptomatic at a 10-year follow-up.

Brain and spinal MRI features distinguishing MS from different AQP4 antibody serostatus NMOSD at disease onset in a cohort of Latin American patients.

OBJECTIVE: We aimed to evaluate magnetic resonance imaging (MRI) previously used criteria (Matthews's criteria, MC) for differentiating multiple sclerosis (MS) from neuromyelitis optica spectrum disorders (NMOSD) in Caucasian and non-Caucasian populations (Argentina, Brazil and Venezuela) with positive (P-NMOSD), negative (N-NMOSD), and unknown (U-NMOSD) aquaporin-4 antibody serostatus at disease onset and to assess the added diagnostic value of spinal cord MRI in these populations. METHODS: We reviewed medical records, and MRIs were assessed by two blinded evaluators and were scored using MC. Short-segment transverse myelitis (STM) was added as a new criterion. MC sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were determined. RESULTS: We included 282 patients (MS = 188 and NMOSD = 94). MC applied to the entire cohort showed 97.8% sensitivity, 82.9% specificity, 92.0% PPV, and 95.1% NPV for differentiating MS from NMOSD. A subanalysis applied only to non-Caucasian (MS = 89 and NMOSD = 47) showed 100% sensitivity, 80.8% specificity, 90.8% PPV, and 100% NPV. Similar sensitivity, specificity, PPV, and NPV of MC for MS versus P-NMOSD (n = 55), N-NMOSD (n = 28), and U-NMOSD (n = 21) were observed. CONCLUSION: MC distinguished MS from NMOSD of all serostatus in a Latin American cohort that included non-Caucasian populations. Addition of STM to MC did not raise the accuracy significantly.

Multiple sclerosis and neuromyelitis optica spectrum disorders in Argentina: comparing baseline data from the Argentinean MS Registry (RelevarEM).

The objective of this study was to describe and compare the baseline epidemiological data of multiple sclerosis (MS) and neuromyelitis optica spectrum disorder (NMOSD) patients included in RelevarEM (Clinical Trials registry number NCT03375177). METHODS: RelevarEM is a longitudinal, strictly observational MS and NMOSD registry in Argentina. Epidemiological and comorbidity data from MS and NMOSD patients were described and compared. For comorbidities, the Charlson comorbidity index (CCI) was used to calculate the burden at entry. CCI was stratified in 0 and ≥ 1 and described for the entire cohort. RESULTS: A total of 1588 and 75 MS and NMOSD patients (respectively) were included. For MS patients, the mean age was 42 ± 7 years, female sex 65.3%, mean EDSS 2, and mean disease duration 8 ± 6 years. In NMOSD, the mean age was 40 ± 7 years, female sex 78.7%, mean disease duration 5 ± 3.5 years, and mean EDSS 2.5. The most frequent MS phenotype was RRMS in 82.4%. In MS, the CCI was 0 in 85.8.2% while ≥ 1 was in 14.2% of patients. Regarding phenotype stratification, CCI ≥ 1 was 3.9% in CIS, 13.5% in RRMS, 28.7% in SPMS, and 17.4% in PPMS (p < 0.001 between groups). In NMOSD, the CCI was 0 in 64% while ≥ 1 was in 36%. The MS/NMOSD ratio found was 21/1. CONCLUSIONS: This is the first analysis of the longitudinal Argentinean registry of MS and NMOSD describing and comparing conditions that contributes to provide reliable real-world data in the country.

Fibromyalgia and dissociative symptoms.

BACKGROUND: Fibromyalgia (FM) is a chronic pain syndrome with a controversial etiopathogenesis. Patients with FM usually complain of cognitive symptoms, which are described as "fibrofog." These cognitive complaints might be caused partially by dissociative disorders (DD). The aim of this research is to determine the association between FM and DD. METHODS: The authors conducted a case-control study for this purpose, integrated by 3 groups: control (C), patients with rheumatic disorders (R), and patients with FM (FM), who were compared through the Dissociative Experiences Scale (DES).The findings are as follows: 42% were taking medications in the FM group, and their differences in scores with those who were not under medications were then considered. In terms of the results, the FM group showed higher scores than both C and R groups (p < 0.05). Patients with FM who were taking antidepressants had lower scores than those who were not (Z-score -8.03; p < 0.05); and finally, 5.71% had a score over 30 (χ2 = 3.73, p = 0.15). CONCLUSION: Patients with FM had higher scores, which might be related to the association of dissociative experiences, lifetime trauma, and victimization. Antidepressants might have some role on dissociative symptoms as well.

Short-segment transverse myelitis lesions in a cohort of Latin American patients with neuromyelitis optica spectrum disorders.

STUDY DESIGN: Multicenter retrospective study. OBJECTIVES: The aim was to determine the frequency and magnetic resonance imaging (MRI) features of short-segment transverse myelitis (STM) in patients with neuromyelitis optica spectrum disorders (NMOSD) during a myelitis attack. SETTING: Latin American diagnostic centres (Neuroimmunology Unit). A multicenter study from Argentina, Brazil and Venezuela was performed. METHODS: Seventy-six patients with NMOSD were included. We analyzed 346 attacks and reviewed spinal cord MRIs performed within 30 days from spinal attack onset. Sagittal and axial characteristics on cervical and thoracic MRI (1.5 tesla) were observed. Demographics, clinical, serological, and disability data were collected. RESULTS: Among the 76 patients with NMOSD, isolated STM was observed in 8% (n = 6), multisegmental lesions (longitudinally extensive transverse myelitis (LETM) + STM) in 28% (n = 21; 13 had at least one STM), LETM in 42% (n = 32), and normal spinal MRI in 22% (n = 17). However, isolated STM was increased by 10% in patients with NMOSD with spinal lesions (6 out of 59) with mean attacks of 2.5 (±0.83) and last follow-up expanded disability status scale (EDSS) of 3.1 (±2.63). Positive aquaporin 4 antibodies (AQP4-ab) were found in 50%. Upper-cervical lesion was most frequently observed (5 out of 6). Myelitis was preceded by ON in all isolated patients with STM. Only one had a positive gadolinium lesion and none of these had asymptomatic spinal cord lesion. CONCLUSION: Isolated STM does not exclude NMOSD diagnosis. Therefore, APQ4-ab testing could be useful during a myelitis attack with STM.

Treatment strategies and responses for attacks of neuromyelitis optica spectrum disorder: A real-world retrospective cohort study.

We aimed to assess the treatment strategies utilized in patients with neuromyelitis optica spectrum disorder (NMOSD) experiencing relapses, including their frequency, types, and response after 6 months based on the Expanded Disability Status Scale (EDSS) score. METHODS: We conducted a retrospective study involving NMOSD patients from the Argentinean MS and NMOSD registry (RelevarEM, NCT03375177). Treatment response at 6 months was categorized as "good" if the EDSS score decreased by ≥1 point after a nadir EDSS score ≤ 3, or by ≥2 points after a nadir EDSS score > 3, "poor" if the EDSS score decrease was slighter, and as "absent" if the EDSS score remained unchanged or worsened. RESULTS: We included 120 NMOSD patients (seropositive N = 75), who experienced 250 NMOSD-related relapses and received 248 treatments. At 6 months, complete recovery was achieved in 70/98 (71.4%) and 15/19 (79%) patients, respectively. Predictors of a "good" response in our regression model were a younger age at disease onset (OR:3.54, CI95% 2.45-5.01, p < 0.0001) and a short delay from onset of relapse to treatment initiation (OR:1.56, CI95% 1.22-2.13, p = 0.004). CONCLUSIONS: Approximately two-thirds of patients experienced complete recovery, and younger age and a short delay to start treatment were independent predictors of a "good" response.

Therapeutic strategies in NMOSD and MOGAD patients: A multicenter cohort study in Latin America.

PURPOSE: This study describes the therapeutic strategies in NMOSD and MOGAD adopted by neurologists to treat both conditions in Latin America (LATAM) with main focus on rituximab (RTX) and the disease outcome. METHODS: retrospective study in a cohort of NMOSD and MOGAD patients followed in specialized MS/NMOSD centers from eight countries and 14 LATAM reference centers. Demographics and clinical characteristics were collected. RTX strategies on naïve (for rituximab) patients were summarized as follows: scheme A: two 1000 mg infusions 15 days apart and repeated every 6 months; scheme B: four 375 mg/m2 infusions every week for 4 weeks and repeated every 6 months; scheme C: one 1000 mg infusions and repeated every 6 months; scheme D: other scheme used. Relapse rate and adverse events during follow-up were analyzed considering the different RTX schemes. Poisson and logistic regression analysis were used to assess baseline aspects and disease activity during follow-up. RESULTS: A total of 217 patients were included. 197 were NMOSD patients (164, 83.2% AQP4-IgG seropositive and 16.7% seronegative) and 20 were MOGAD patients. The most frequent long-term treatment was RTX in both groups (48.2% and 65% for NMOSD and MOGAD patients, respectively). The most common RTX regimen used in 79 (83.1%) patients was two 1000 mg infusions 15 days apart and repeat every 6 months. Relapses under RTX treatment were observed in 21 (22.1%) patients. Relapses after RTX treatment were associated with higher EDSS (OR 1.75, 95%CI 1.44-2.34, p = 0.03) and higher ARR pre-RTX (OR = 2.17, 95% CI 1.72-3.12, p = 0.002) but not with RTX regimen (OR = 1.10, 95% CI 0.89-1.21, p = 0.60). CONCLUSION: the most strategy used in LATAM was RTX with two 1000 mg infusions 15 days apart. Relapses during follow up were not associated with RTX regimen used.

Clinical outcomes and prognostic factors in patients with optic neuritis related to NMOSD and MOGAD in distinct ethnic groups from Latin America.

BACKGROUND: Optic neuritis (ON) can be an initial manifestation of neuromyelitis optica spectrum disorder (NMOSD) associated with aquaporin 4-antibody (AQP4-Ab) or myelin oligodendrocyte glycoprotein antibody (MOG-Ab)-associated disease (MOGAD). Additionally, both diseases may have overlapping paraclinical and radiological features. These diseases may have different outcomes and prognoses. We aimed to compare clinical outcomes and prognostic features of patients with NMOSD and MOGAD presenting ON as first attack, from different ethnic groups in Latin America. METHODS: We conducted a retrospective observational multicenter study in patients from Argentina (n = 61), Chile (n = 18), Ecuador (n = 27), Brazil (n = 30), Venezuela (n = 10) and Mexico (n = 49) with MOGAD or NMOSD related ON. Predictors of disability outcomes at last follow-up, namely visual disability (Visual Functional System Score ≥4), motor disability (permanent inability to walk further than 100 m unaided) and wheelchair dependence based on EDSS score were evaluated. RESULTS: After a mean disease duration of 42.7 (±40.2) months in NMOSD and 19.7 (±23.6) in MOGAD, 55% and 22% (p>0.001) experienced permanent severe visual disability (visual acuity from 20/100 to 20/200), 22% and 6% (p = 0.01) permanent motor disability and 11% and 0% (p = 0.04) had become wheelchair dependent, respectively. Older age at disease onset was a predictor of severe visual disability (OR=1,03 CI95%1.01-1.05, p = 0.03); older age at disease onset (OR=1,04 CI95%1.01-1.07, p = 0.01), higher number of relapses (OR=1,32 CI95%1.02-1.71, p = 0.03) and rituximab treatment (OR=0,36 CI95%0.14-0.90, p = 0.02) were predictors of permanent motor disability, whereas ON associated with myelitis at disease onset was a predictor of wheelchair dependency (OR=4,16, CI95%1.23-14.08, p = 0,02) in NMOSD patients. No differences were found when evaluating distinct ethnic groups (Mixed vs. Caucasian vs. Afro-descendant) CONCLUSIONS: NMOSD was associated with poorer clinical outcomes than MOGAD. Ethnicity was not associated with prognostic factors. Distinct predictors of permanent visual and motor disability and wheelchair dependency in NMOSD patients were found.

Mortality of neuromyelitis optica spectrum disorder patients in an Argentinean population: A study from the RelevarEM registry.

We aimed to evaluate mortality and causes of death among Argentinean neuromyelitis optica spectrum disorder (NMOSD) patients and identify predictors of death. Retrospective study included 158 NMOSD patients and 11 (7%) patients died after 11 years of follow-up for a total exposure time of 53,345 days with an overall incidence density of 2.06 × 10.000 patients/day (95% CI 1.75-2.68). Extensive cervical myelitis with respiratory failure (45%) was the most frequent cause of death. Older age (HR = 2.05, p = 0.002) and higher disability score (HR = 2.30, p < 0.001) at disease onset were independent predictors of death. We found an 11-year mortality rate of 7% in Argentinean NMOSD patients.

Effectiveness and Safety of Early High-Efficacy Versus Escalation Therapy in Relapsing-Remitting Multiple Sclerosis in Argentina.

OBJECTIVE: Escalation (ES) and early high-efficacy (EHE) therapies have been the main treatment strategies adopted in multiple sclerosis (MS) in recent years. The aim of this study was to compare the effectiveness and safety of EHE versus ES strategies in MS patients from Argentina. METHODS: This is a retrospective multicenter cohort study in Argentina. Eligible patients were categorized into 2 groups as follows: EHE if received natalizumab, ocrelizumab, rituximab, alemtuzumab, mitoxantrone, or cladribine; and ES if received interferon ß, glatiramer acetate, teriflunomide, dimethyl fumarate, or fingolimod as initial therapy. The primary outcome was confirmed disability progression (Expanded Disability Status Scale [EDSS] increase). Additional outcomes included the proportion of patients and time to: EDSS 6; new relapses; new T2-magnetic resonance imaging (MRI) lesions; no evidence of disease activity; and specific adverse events. Propensity score-based nearest-neighbor matching (without replacement) was applied to homogenize the sample, and Cox regression model stratified by matched pairs was used for the analysis. RESULTS: After propensity score matching, 193 and 112 patients were retained in the ES and EHE groups, respectively. The EHE significantly decreased the risk of EDSS progression (hazard ratio [HR], 0.62; 95% confidence interval [95% CI], 0.40-0.98; P = 0.04), relapses (HR, 0.66; 95% CI, 0.49-0.89; P = 0.006), and new MRI activity during follow-up (HR, 0.55; 95% CI, 0.40-0.75; P < 0.001). No significant differences were observed in specific adverse events between groups. CONCLUSIONS: Our study shows that EHE therapies prevent disease progression, relapses, and new MRI lesions and demonstrated no increased risk of specific adverse events when compared with ES therapy. These data should be considered when selecting a specific treatment for MS patients.

Platelet-to-lymphocyte ratio differs between MS and NMOSD at disease onset and predict disability.

BACKGROUND: We aimed to assess platelet-to-lymphocyte (PLR) and neutrophil-to-lymphocyte ratios (NLR) for differentiating multiple sclerosis (MS) from aquaporin-4-antibody-positive neuromyelitis optica spectrum disorders (NMOSD) at disease onset. METHODS: We retrospectively enrolled and reviewed the medical records of patients with MS (N = 50) and NMOSD (N = 33) followed in specialized MS/NMOSD centers from Argentina. Demographical and clinical (manifestation and disability) data and neuroradiological features (new/enlarging or contrast-enhancing lesions) were assessed at baseline, 1 and 2 years. Serum samples were obtained during the first relapse without a previous acute or chronic treatment, at 1 and 2 years. Mixed-effects model was used to identify independent associations between the log-transformed NLR or PLR and MS/NMOSD outcomes. RESULTS: PLR is increased in NMOSD when compared to MS (229.4 ± 86.74 vs. 186.6 ± 70.17, P = 0.01), but no significant differences were found for NLR (3.51 ± 1.29 vs. 3.30 ± 1.17, P = 0.43). PLR was the only independent predictor of poor physical disability score (EDSS ≥ 4) in NMOSD patients at 2 years (ß=0.28, p = 0.02) after applying multivariate mixed-effects regression analysis. Additionally, multivariate logistic regression analysis showed that the PLR was the only independent predictor of EDSS ≥ 4 at 2 years (OR 28.8, p = 0.041) in the NMOSD group. The area under the receiver-operating characteristic curve was 0.841. CONCLUSION: PLR could be potentially useful as additional diagnostic tool in differentiating these two neuroinflammatory conditions at presentation. PLR can predict severity of neurological disability at 2 years in NMOSD patients.

Seasonal variation in attacks of neuromyelitis optica spectrum disorders and multiple sclerosis: Evaluation of 794 attacks from a nationwide registry in Argentina.

BACKGROUND: Identification of triggers that potentially instigate attacks in neuromyelitis optica spectrum disorders (NMOSD) and multiple sclerosis (MS) has remained challenging. We aimed to analyze the seasonality of NMOSD and MS attacks in an Argentinean cohort seeking differences between the two disorders. METHODS: A retrospective study was conducted in a cohort of NMOSD and MS patients followed in specialized centers from Argentina and enrolled in RelevarEM, a nationwide, longitudinal, observational, non-mandatory registry of MS/NMOSD patients. Patients with complete relapse data (date, month and year) at onset and during follow-up were included. Attack counts were analyzed by month using a Poisson regression model with the median monthly attack count used as reference. RESULTS: A total of 551 patients (431 MS and 120 NMOSD), experiencing 236 NMOSD-related attacks and 558 MS-related attacks were enrolled. The mean age at disease onset in NMOSD was 39.5 ± 5.8 vs. 31.2 ± 9.6 years in MS (p < 0.01). Mean follow-up time was 6.1 ± 3.0 vs. 7.4 ± 2.4 years (p < 0.01), respectively. Most of the included patients were female in both groups (79% vs. 60%, p < 0.01). We found a peak of number of attacks in June (NMOSD: 28 attacks (11.8%) vs MS: 33 attacks (5.9%), incidence rate ratio 1.82, 95%CI 1.15-2.12, p = 0.03), but no differences were found across the months in both disorders when evaluated separately. Strikingly, we observed a significant difference in the incidence rate ratio of attacks during the winter season when comparing NMOSD vs. MS (NMOSD: 75 attacks (31.7%) vs MS: 96 attacks (17.2%), incidence rate ratio 1.82, 95%CI 1.21-2.01, p = 0.02) after applying Poisson regression model. Similar results were observed when comparing the seropositive NMOSD (n = 75) subgroup vs. MS. CONCLUSIONS: Lack of seasonal variation in MS and NMOSD attacks was observed when evaluated separately. Future epidemiological studies about the effect of different environmental factors on MS and NMOSD attacks should be evaluated prospectively in Latin America population.

Real-world effectiveness of natalizumab treatment in patients with relapsing multiple sclerosis in Argentina and Chile.

BACKGROUND: The real-world effectiveness of natalizumab in people with relapsing multiple sclerosis (PwRMS) in Argentina and Chile has not been reported. OBJECTIVE: To evaluate the effectiveness of natalizumab treatment in PwRMS in Argentina and Chile, in clinical practice. METHODS: We conducted a multicenter retrospective and observational study. We reviewed the medical records of PwRMS who had been treated with natalizumab for at least one year, without any interruption in MS treatment that lasted more than 12 weeks. We analyzed changes in annualized relapse rate (ARR), Expanded Disability Status Scale (EDSS) score and magnetic resonance imaging (MRI). RESULTS: We enrolled 117 PwRMS treated with natalizumab. Natalizumab treatment was associated with a significant reduction in ARR from baseline after one year and two years of treatment (from 1.97 to 0.06 and 0.09 respectively; p<0.01 at each time point). From baseline, EDSS scores were reduced by 0.71 and 0.73 points at one and two years, respectively (p<0.01). No worsening of disability was observed in 82.9 and 67.5% of PwRMS at one and two years, respectively. The improvement in disability was 44.4% at one year and 39.3% at two years. During natalizumab treatment, the number of relapse-related hospitalizations was significantly reduced (p<0.01). MRI lesions (new/enlarging T2 or gadolinium-enhancing) were significantly reduced, compared with baseline. No evidence of disease activity was observed in 65% at two years of natalizumab treatment. CONCLUSIONS: Natalizumab significantly reduced disease activity in PwRMS in Argentina and Chile, in clinical practice. Natalizumab also decreased the number of hospitalizations compared with pre-natalizumab treatment.

Employment status in people with relapsing multiple sclerosis from Argentina: Impact of disability and neuropsychological factors.

BACKGROUND: Unemployment is common in people with multiple sclerosis (PwMS) and might be prevented if factors associated with work loss are identified. OBJECTIVE: We aimed to assess the impact of multiple sclerosis (MS) on employment status in a cohort of PwMS from Argentina and to evaluate their association with anxiety, depression, fatigue and disability. METHODS: A cross-sectional study was conducted to assess employment in PwMS using an anonymous, self-administered questionnaire, which also included the Hospital Anxiety and Depression Scale, Fatigue Severity Scale and Expanded Disability Status Scale. The data was compared between employed (full-time vs. part-time) vs. unemployed (looking for vs. not looking for work) PwMS. Univariate and multivariate models were designed to identify factors independently associated with unemployment. RESULTS: Among the 167 PwMS, 120 (71.6%, full-time = 65%) were employed, and 47 (28.4%, looking for work = 27.6%) were currently unemployed. Age, gender, and duration of disease were similar in both groups. Univariate analysis showed that anxiety, depression, fatigue and disability were significantly associated with unemployed PwMS. However, only disability (OR = 1.36 (1.08-1.70), p = 0.007) was independently associated with unemployment after applying multivariate analysis (logistic regression). CONCLUSION: Nearly one-third of PwMS from this sample in Argentina were unemployed. Neuropsychological factors and disability were associated with unemployment status.

Coping strategies used by patients with relapsing multiple sclerosis from Argentina: correlation with quality of life and clinical features.

BACKGROUND: Multiple sclerosis (MS) is a chronic neurodegenerative and inflammatory disease. The adaptation to MS depends on the effectiveness of coping, which moderates the process of adaptation and psychological well-being. OBJECTIVES: We aimed to analyze the coping strategies of an Argentinean population of patients with MS (PwMS) and their association with clinical variables and health-related quality of life (QoL). METHODS: A nationwide cross-sectional study. Screening instruments: Demographics and clinical data, coping strategies (Brief Coping Orientation to Problems Experienced, [COPE-28]), health-related QoL (MS Impact Scale, [MSIS-29]), Fatigue Severity Scale, and physical disability (self-administrated Expanded Disability Status Scale, [EDSS]). RESULTS: We included 249 PwMS. Most responders were female (74.7%) with a mean age at survey of 38.6 (±10.7) and had a MS duration of 7.3 years (range: 1-43 years) and a mean EDSS of 1.9 (±1.8). Younger age (r = -0.17), active MS (r = 0.25), higher fatigue (r = 0.22), MSIS-29 total (r = 0.34), MSIS-physical (r = 0.26), MSIS-psychological scores (r = 0.44), higher scores for perception of both severity of MS (r = 0.12) and wheelchair-dependency (r = 0.14) correlated significantly with the use of maladaptive coping strategies. However, active MS (ß2.10, p = 0.01), MSIS-psychological score (ß0.28, p < 0.0001), high education level (ß - 1.15, p = 0.04), and EDSS (ß - 0.84, p = 0.0001) were independent predictors of the utilization of maladaptive coping strategies after having applied multivariate analysis via linear regression. CONCLUSIONS: Maladaptive coping strategies used by PwMS are associated with relevant clinical aspects of the disease and with worse health-related QoL scores.