Relapse Patterns in NMOSD: Evidence for Earlier Occurrence of Optic Neuritis and Possible Seasonal Variation

Detecting seasonal trends in optic neuritis within the Ottawa region

OBJECTIVE

In this study we aim to determine seasonal patterns underlying optic neuritis (ON) onset that may provide valuable epidemiologic information and help delineate causative or protective factors.

DESIGN

Single-centre retrospective chart review.

METHODS

A database search of centralized electronic health records was completed using diagnostic codes employed at the Ottawa Eye Institute for data collection. Charts were reviewed for documentation supporting a diagnosis of ON falling into the following categories: multiple sclerosis ON and clinically isolated syndrome ON, myelin oligodendrocyte glycoprotein ON, neuromyelitis optica ON, and idiopathic ON. Date of onset, biological sex, and age were extracted from each chart. Data were analyzed for calculation of frequency by season and overall pooled seasonal trends of all cases of ON.

RESULTS

From the 218 included patients with ON, there was no statistically significant seasonal correlation. The overall trend of ON was lowest in winter and spring (22% and 23%, respectively) and highest in summer and fall (28% and 27% respective). Divided further, multiple sclerosis ON or clinically isolated syndrome ON rates (n = 144) were lowest in the spring (21%) and highest in fall (29%); myelin oligodendrocyte glycoprotein ON rates (n = 25) were lowest in winter (16%) and highest in summer and fall (both at 32%); neuromyelitis optica ON rates (n = 16) were lowest in fall (12.5%) and highest in winter and summer (both at 31.25%); and idiopathic ON rates (n = 33) were lowest in fall (18%) and highest in spring (33%).

CONCLUSIONS

The overall ON seasonal trend appears to have a predilection for the summer and fall months, which may be explained by warmer weather and viral infections as risk factors for multiple sclerosis relapse during those seasons.

Characteristics of recurrence risk perception and coping strategies in patients with neuromyelitis optica spectrum disorder: A qualitative study

BACKGROUND

Although neuromyelitis optica spectrum disorder (NMOSD) has high recurrence and disability rates, cases of relapses can be recognized, and timely intervention can be provided if the risk of relapse is properly perceived. However, there have been no studies to explore patients' perceptions of recurrence risk and coping strategies. This study aimed to explore the characteristics of relapse risk perception and coping strategies of patients with NMOSD.

METHODS

We adopted the phenomenological method of qualitative research. Face-to-face, semi-structured in-depth interviews were conducted with 15 patients with NMOSD. The interview data were then analyzed using the Colaizzi seven-step analysis.

RESULTS

The analysis revealed five major themes. The first theme was the 'perception of possibility of relapse', which included subjectively underestimating the likelihood of relapse and shifted from underestimation to overestimation; the second theme was 'relapse warning signs perception'; the third theme was 'perception of relapse triggers', which included understanding relapse triggers, potential misconceptions about relapse triggers, and no identifiable cause of recurrence; the fourth theme was 'perception of the relapse consequences', encompassing severe impairment of body structure and function, prominent psychological problems, limited family roles and social functions, and heavy financial burden; and the final theme was 'relapse risk coping strategies', which included actively yearning for and seeking information support, recurrence risk prevention/management, limitations of coping strategies.

CONCLUSIONS

This study's findings revealed that newly diagnosed patients as well as those who relapsed subjectively underestimated the likelihood of relapse before they had experienced multiple (two or more) relapses. In contrast, patients who had experienced multiple relapses had transitioned from initial underestimation to subsequent overestimation. Additionally, patients' compliance with medication was identified as a relapse-risk behaviors that was very manageable. The occurrence of relapse is associated with significant and extensive adverse effects on patients. Consequently, patients are eager to communicate with their healthcare providers regarding treatment planning and relapse management.

A comprehensive review of the advances in neuromyelitis optica spectrum disorder

Neuromyelitis optica spectrum disorder (NMOSD) is a rare relapsing neuroinflammatory autoimmune astrocytopathy, with a predilection for the optic nerves and spinal cord. Most cases are characterised by aquaporin-4-antibody positivity and have a relapsing disease course, which is associated with accrual of disability. Although the prognosis in NMOSD has improved markedly over the past few years owing to advances in diagnosis and therapeutics, it remains a severe disease. In this article, we review the evolution of our understanding of NMOSD, its pathogenesis, clinical features, disease course, treatment options and associated symptoms. We also address the gaps in knowledge and areas for future research focus.

Hospital Readmission Rates in Patients With Neuromyelitis Optica Spectrum Disorder

BACKGROUND

Neuromyelitis optica spectrum disorder (NMOSD) is an aggressive central nervous system astrocytopathy often resulting in rapid neurologic decline. Patients have recurrent flares that require immunomodulatory therapy for relapse prevention. These patients are usually hospitalized and may need rehospitalization after decline. Hospital readmission rates are important indicators that can be used to gauge health care quality and have direct implications on hospital compensation. This study aims to identify high-risk characteristics of patients with NMOSD that can be used to predict hospital readmissions.

METHODS

The 2017 Nationwide Readmissions Database was searched for hospital admissions for NMOSD in the United States. All patients with hospital readmission within 30 days of discharge from the index hospitalization were included.

RESULTS

The 30-day all-cause readmission rate for NMOSD was 11.9% (95% CI, 10.6%-13.3%). Patients aged 65 to 74 years had higher odds of readmission; those with private insurance had decreased odds. Sex did not affect readmission. Several comorbidities, such as respiratory failure, peripheral vascular disease, neurocognitive disorders, and neurologic blindness, were predictive of readmissions. Plasma exchange increased the odds of readmission, whereas intravenous immunoglobulin and immunomodulatory infusions, such as chemotherapies and monoclonal antibodies, did not affect readmission.

CONCLUSIONS

The most common etiologies for 30-day read-mission were neurologic, infectious, and respiratory. Treatment targeted toward these etiologies may result in reduced overall readmission, thereby decreasing overall disease burden.

Overlap syndrome of anti-aquaporin 4 positive neuromyelitis optica spectrum disorder and primary Sjögren's syndrome: a systematic review of individual patient data

Central nervous system (CNS) involvement can occur in primary Sjögren's syndrome (pSS) due to co-existing neuromyelitis optica spectrum disorder (NMOSD) which has a highly relapsing course requiring indefinite immunosuppression, and if not diagnosed early, damage accrual occurs over time leading to permanent disability and morbidity. In this review, we describe and outline the clinical course and outcomes of anti-aquaporin 4 (AQP4) antibody seropositive NMOSD with pSS overlap cases. To investigate the co-existence of AQP4 + NMOSD with pSS, we conducted a review of individual patient data from case reports and case series found in major databases. The study extracted clinico-demographic features, imaging and laboratory profiles, treatment approaches, and outcomes of these patients. Inclusion criteria for the review required patients to have positivity for anti-AQP4 or NMO-IgG autoantibodies in the blood and/or cerebrospinal fluid (CSF) and exhibit at least one manifestation of both pSS and NMOSD. In this overlap between AQP4 + NMOSD and pSS, 44 patients were included of whom 41 (93.2%) were females. The mean age of pSS onset was 44.8 ± 18.4 years and NMOSD onset was 43.2 ± 19.8 years. In 20 (45.5%) patients, NMOSD preceded pSS onset, 13 (29.5%) NMOSD occurred after pSS onset, and 11 (25%) patients had a simultaneous presentation. 31 (70.5%) patients experienced acute transverse myelitis, 21 (47.7%) optic neuritis, 14 (31.8%) cerebral syndrome, 10 (22.7%) acute brainstem syndrome, 5 (11.4%) area postrema syndrome, and 2 (4.5%) diencephalic clinical syndromes. For the treatment of acute phase, 40 (90.9%) patients received intravenous methylprednisolone, 15 (34.1%) received plasma exchange, and 10 (22.7%) received intravenous immunoglobulin; and for the induction/maintenance therapy, 16 (36.4%) patients received cyclophosphamide, 6 (13.6%) received rituximab, 16 (36.4%) received azathioprine, and 10 (22.7%) received mycophenolate mofetil. Disease course was monophasic in 2 (4.5%) and relapsing in 27 (61.4%) patients. At median (IQR) follow-up duration of 2.4 (6) years, 39 (88.6%) patients showed improvement, 3 (6.8%) showed stabilization and 2 (4.5%) showed worsening of their NMOSD manifestations. In this overlap syndrome of AQP4 + NMOSD and pSS, patients have a neurologically disabling disorder that can mimic neurological manifestations of pSS, frequently occurs prior to the onset of pSS, has a relapsing course, responds well to immunosuppressants, and necessitates indefinite treatment. Collaborative multicentre studies are needed to clarify the natural history and outcomes of this rare overlap syndrome.

Inpatient care of neuromyelitis optica spectrum disorder in Germany: Nationwide analysis from 2010 to 2021

Background

Despite tremendous development in the treatment of neuromyelitis optica spectrum disorder (NMOSD), less is known about the characteristics of hospitalized patients and inpatient care utilization.

Objective

To investigate the development of inpatient NMOSD case numbers and implemented immunotherapies in the last decade in Germany.

Methods

We conducted a nationwide retrospective study using an administrative database of all hospitalized NMOSD patients between 2010 and 2021. We evaluated yearly data on case numbers, demographics, treatment regimens, and seasonal variations of apheresis therapy as a surrogate marker of severe relapse incidence.

Results

During the observational period case number of inpatients substantially increased (2010:n = 463, 2021:n = 992). The mean age was 48.1 ± 2.5 years (74% females). The pooled yearly rate of plasmapheresis/immunoadsorption was 14% (95% CI [13-15%]), without seasonal variations. Its application peaked in 2013 (18%, 95% CI [15-21%]) with decreasing trend since. Predominant immunotherapy was rituximab (40%, 95% CI [34-45%]), followed by tocilizumab (4%, 95% CI [3-5%]) since 2013 and eculizumab (4%, 95% CI [3-5%]) since 2020. Inpatient mortality ranged between 0% and 1% per year.

Conclusions

Inpatient case numbers of NMOSD substantially increased during the past decade, probably reflecting improving disease awareness. In parallel with the administration of highly effective therapies rate of apheresis therapies decreased. A stable apheresis rate over the year makes seasonal variations of the steroid-refractive relapses unlikely.

Clinical and epidemiological correlates of treatment change in patients with NMOSD: insights from the CIRCLES cohort

OBJECTIVE

Neuromyelitis optica spectrum disorders (NMOSD) represent rare autoimmune diseases of the central nervous system largely targeting optic nerve(s) and spinal cord. The present analysis used real-world data to identify clinical and epidemiological correlates of treatment change in patients with NMOSD.

METHODS

CIRCLES is a longitudinal, observational study of NMOSD conducted at 15 centers across North America. Patients with ≥ 60 days of follow-up and receiving on-study maintenance treatment were evaluated. The mean annual relapse rate (ARR) was estimated using negative binomial models; the likelihood of treatment change was estimated using Cox proportional hazards models. Relapses were included as time-varying covariates to estimate the relationship to treatment change.

RESULTS

Of 542 patients included, 171 (31.5%) experienced ≥ 1 relapse on the study and 133 patients (24.5%) had ≥ 1 change in the treatment regimen. Two categories of variables significantly correlated with the likelihood of treatment change: (1) relapse: any on-study relapse (hazard ratio [HR] = 2.91; p < 0.001), relapse phenotypes (HR range = 2.15-5.49; p < 0.001), and pre-study ARR > 0.75 (HR 2.28; p < 0.001); 2) disease phenotype: brain syndrome only vs transverse myelitis involvement at onset (HR 2.44; p = 0.008), disease duration < 1 vs > 5 years (HR 1.66; p = 0.028), or autoimmune comorbidity (HR 1.55; p = 0.015). A subset of these factors significantly correlated with shorter time to first rituximab discontinuation.

CONCLUSIONS

In CIRCLES, relapse patterns and disease phenotype significantly correlated with changes in the maintenance treatment regimen. Such findings may facilitate the identification of patients with NMOSD who are likely to benefit from treatment change to reduce relapse risk or disease burden and enhance the quality of life.

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.

Predictive role of blood-based indicators in neuromyelitis optica spectrum disorders

Introduction

This study aimed to assess the predictive role of blood markers in neuromyelitis optica spectrum disorders (NMOSD).

Methods

Data from patients with NMOSD, multiple sclerosis (MS), and healthy individuals were retrospectively collected in a 1:1:1 ratio. The expanded disability status scale (EDSS) score was used to assess the severity of the NMOSD upon admission. Receiver operating characteristic (ROC) curve analysis was used to distinguish NMOSD patients from healthy individuals, and active NMOSD from remitting NMOSD patients. Binary logistic regression analysis was used to evaluate risk factors that could be used to predict disease recurrence. Finally, Wilcoxon signed-rank test or matched-sample t-test was used to analyze the differences between the indicators in the remission and active phases in the same NMOSD patient.

Results

Among the 54 NMOSD patients, neutrophil count, neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and systemic immune-inflammation index (SII) (platelet × NLR) were significantly higher than those of MS patients and healthy individuals and positively correlated with the EDSS score of NMOSD patients at admission. PLR can be used to simultaneously distinguish between NMOSD patients in the active and remission phase. Eleven (20.4%) of the 54 patients had recurrence within 12 months. We found that monocyte-to-lymphocyte ratio (MLR) (AUC = 0.76, cut-off value = 0.34) could effectively predict NMOSD recurrence. Binary logistic regression analysis showed that a higher MLR at first admission was the only risk factor for recurrence (p = 0.027; OR = 1.173; 95% CI = 1.018-1.351). In patients in the relapsing phase, no significant changes in monocyte and lymphocyte count was observed from the first admission, whereas patients in remission had significantly higher levels than when they were first admitted.

Conclusion

High PLR is a characteristic marker of active NMOSD, while high MLR is a risk factor for disease recurrence. These inexpensive indicators should be widely used in the diagnosis, prognosis, and judgment of treatment efficacy in NMOSD.

Relevance of bright spotty lesions in neuromyelitis optica spectrum disorders (NMOSD): a case series

Background

Neuromyelitis optica (NMO), or neuromyelitis optica spectrum disorder (NMOSD), is an autoimmune CNS condition which often has a complex clinical course. Longitudinally extensive transverse myelitis (LETM) is an important and sensitive MRI finding but is not very specific to NMOSD and is seen in other causes of myelitis.

Case presentations

We report 11 NMO cases, all seen in women from 25 to 75 years at the time of diagnosis, with most above 65 years of age. All patients were seropositive for AQP4–IgG antibodies, and none had anti-MOG antibodies. Clinical presentations were diverse, the most common being paralytic and visual changes. In this study, 5 of the 11 seropositive NMO patients (45%) had bright spotty lesion (BSLs) on their MRI spine, as opposed to none (0%) in the control group. BSLs were defined as hyperintense foci of signal abnormality on T2-weighted images compared to the surrounding CSF. Treatment included symptomatic management and immunotherapy; timely management led to improvement in all the cases, with partial recovery seen in most (91%) and complete recovery seen only in one.

Conclusions

BSLs are a newly defined spinal MRI finding with high specificity, but low sensitivity for NMOSD. The absence of BSLs in the control group establishes its prolific role in distinguishing NMO from MS, ITM, MOGAD and other forms of myelitis. The main aim of this retrospective case–control study was to determine the diagnostic importance and specificity of bright spotty lesions (BSLs) in NMOSD and its ability to discriminate NMOSD from other causes of LETM.

Neuromyelitis Optica Spectrum Disorders

PURPOSE OF REVIEW

This article reviews the cardinal clinical features, distinct immunopathology, current diagnostic criteria, relapse-related risk factors, emerging biomarkers, and evolving treatment strategies pertaining to neuromyelitis optica spectrum disorders (NMOSD).

RECENT FINDINGS

The discovery of the pathogenic aquaporin-4 (AQP4)-IgG autoantibody and characterization of NMOSD as an autoimmune astrocytopathy have spearheaded the identification of key immunologic therapeutic targets in this disease, including but not limited to the complement system, the interleukin 6 (IL-6) receptor, and B cells. Accordingly, four recent randomized controlled trials have demonstrated the efficacy of three new NMOSD therapies, namely eculizumab, satralizumab, and inebilizumab.

SUMMARY

Currently, NMOSD poses both diagnostic and treatment challenges. It is debated whether individuals who are seropositive for myelin oligodendrocyte glycoprotein (MOG)-IgG belong within the neuromyelitis optica spectrum. This discussion is fueled by disparities in treatment responses between patients who are AQP4-IgG seropositive and seronegative, suggesting different immunopathologic mechanisms may govern these conditions. As our understanding regarding the immune pathophysiology of NMOSD expands, emerging biomarkers, including serum neurofilament light chain and glial fibrillary acidic protein (GFAP), may facilitate earlier relapse detection and inform long-term treatment decisions. Future research focal points should include strategies to optimize relapse management, restorative treatments that augment neurologic recovery, and practical solutions that promote equitable access to approved therapies for all patients with NMOSD.

NMOSD—Diagnostic Dilemmas Leading towards Final Diagnosis

(1) Background: The emergence of white matter lesions in the central nervous system (CNS) can lead to diagnostic dilemmas. They are a common radiological symptom and their patterns may overlap CNS or systemic diseases and provoke underdiagnosis or misdiagnosis. The aim of the study was to assess factors influencing the underdiagnosis of neuromyelitis optica spectrum disorder (NMOSD) as well as to estimate NMOSD epidemiology in Lubelskie voivodeship, Poland. (2) Methods: This retrospective study included 1112 patients, who were made a tentative or an established diagnosis of acute or subacute onset of neurological deficits. The evaluation was based on medical history, neurological examination, laboratory and radiographic results and fulfilment of diagnosis criteria. (3) Results: Up to 1.62 percent of patients diagnosed with white matter lesions and up to 2.2% of the patients previously diagnosed with MS may suffer from NMOSD. The duration of delayed diagnosis is longer for males, despite the earlier age of onset. Seropositive cases for antibodies against aquaporin-4 have worse prognosis for degree of disability. (4) Conclusions: Underdiagnosis or misdiagnosis in NMOSD still remains a problem in clinical practice and has important implications for patients. The incorrect diagnosis is caused by atypical presentation or NMOSD-mimics; however, covariates such as gender, onset and diagnosis age may also have an influence.

Calculating and Comparing the Annualized Relapse Rate and Estimating the Confidence Interval in Relapsing Neurological Diseases

Calculating the crude or adjusted annualized relapse rate (ARR) and its confidence interval (CI) is often required in clinical studies to evaluate chronic relapsing diseases, such as multiple sclerosis and neuromyelitis optica spectrum disorders. However, accurately calculating ARR and estimating the 95% CI requires careful application of statistical approaches and basic familiarity with the exponential family of distributions. When the relapse rate can be regarded as constant over time or by individuals, the crude ARR can be calculated using the person-years method, which divides the number of all observed relapses among all participants by the total follow-up period of the study cohort. If the number of relapses can be modeled by the Poisson distribution, the 95% CI of ARR can be obtained by finding the 2.5% upper and lower critical values of the parameter λ as the mean. Basic familiarity with F-statistics is also required when comparing the ARR between two disease groups. It is necessary to distinguish the observed relapse rate ratio (RR) between two sample groups (sample RR) from the unobserved RR between their originating populations (population RR). The ratio of population RR to sample RR roughly follows the F distribution, with degrees of freedom obtained by doubling the number of observed relapses in the two sample groups. Based on this, a 95% CI of the population RR can be estimated. When the count data of the response variable is overdispersed, the negative binomial distribution would be a better fit than the Poisson. Adjusted ARR and the 95% CI can be obtained by using the generalized linear regression models after selecting appropriate error structures (e.g., Poisson, negative binomial, zero-inflated Poisson, and zero-inflated negative binomial) according to the overdispersion and zero-inflation in the response variable.

Response to treatment in NMOSD: the Australasian experience

BACKGROUND

Neuromyelitis optica spectrum disorder (NMOSD) is associated with significant morbidity and mortality. Several therapies have been recommended for NMOSD and more recently clinical trials have demonstrated efficacy for three monoclonal antibody therapies. We present a retrospective observational study of treatment response in NMOSD.

METHODS

This was a retrospective, unblinded, observational study of treatment efficacy for rituximab and traditional immunosuppressive therapy in patients with AQP4 antibody positive NMOSD. Treatment efficacy was assessed using annualised relapse rates (ARR), time to first relapse and expanded disability status scale (EDSS) scores.

RESULTS

Complete relapse and treatment data were available for 43/68 (63%) of AQP4 antibody positive NMOSD cases covering 74 episodes of treatment. In a time to first relapse analysis rituximab showed a risk ratio of 0.23 (95% CI 0.08 - 0.65) when compared with no treatment and there was a non-significant reduction in ARR of 35% compared to pre-treatment. β-interferon (p = 0.0002) and cyclophosphamide (p = 0.0034) were associated with an increased ARR compared to pre-treatment. Rituximab (median 4.0 [range 0.0 - 7.0]; p = 0.042) and traditional immunosuppressive therapy (median 4.0 [range 0.0 - 8.0]; p = 0.016) were associated with a lower final EDSS compared to β-interferon (median 6.0 [range 4.0 - 7.5]).

CONCLUSIONS

These data provide additional support for the use of rituximab in preference to traditional immunosuppressive agents and MS disease modifying therapies as first line treatment of NMOSD.

Risk Factors and Nomogram for Predicting Relapse Risk in Pediatric Neuromyelitis Optica Spectrum Disorders

Background

Neuromyelitis optica spectrum disorders (NMOSDs) are attack-relapsing autoimmune inflammatory diseases of the central nervous system, which are characterized by the presence of serological aquaporin-4 (AQP4) antibody. However, this disorder is uncommon in children, and AQP4 antibody was often found to be seronegative. However, some pediatric patients diagnosed with NMOSDs were tested to be positive for myelin oligodendrocyte glycoprotein (MOG) antibody. The previous investigations of pediatric NMOSDs were usually focused on the clinical presentation, treatment responses, and long-term prognoses, but little is known about the risk factors predicting NMOSD relapse attacks in a shorter time, especially, for Chinese children.

Methods

We retrospectively identified 64 Chinese pediatric patients, including 39 positive for AQP4 antibody, 12 positive for MOG antibody, and the rest negative for AQP4 and MOG antibodies. Independent risk factors predicting relapse in 1-year follow-up were extracted by multivariate regression analysis to establish a risk score model, its performance evaluation was analyzed using receiver operating characteristic (ROC) curve, and the independent risk factors related to relapse manifestation were also explored through multivariate logistic analysis. A nomogram was generated to assess relapse attacks in 1-year follow-up. Thirty-five patients from 3 other centers formed an external cohort to validate this nomogram.

Results

Four independent relapsed factors included discharge Expanded Disability Status Scale (EDSS) (p = 0.017), mixed-lesion onset (p = 0.010), counts (≧1) of concomitant autoantibodies (p = 0.015), and maintenance therapy (tapering steroid with mycophenolate mofetil (MMF), p = 0.009; tapering steroid with acetazolamide (AZA), p = 0.045; and tapering steroid only, p = 0.025). The risk score modeled with these four factors was correlated with the likelihood of relapse in the primary cohort (AUC of 0.912) and the validation cohort (AUC of 0.846). Also, our nomogram exhibited accurate relapse estimate in the primary cohort, the validation cohort, and the whole cohort, but also in the cohorts with positive/negative AQP4 antibody, and noticeably, it performed predictive risk improvement better than other factors in the concordance index (C-index), net reclassification improvement (NRI), and integrated discrimination improvement (IDI).

Conclusions

The risk score and nomogram could facilitate accurate prognosis of relapse risk in 1-year follow-up for pediatric NMOSDs and help clinicians provide personalized treatment to decrease the chance of relapse.

Evaluating the Economic Burden of Relapses in Neuromyelitis Optica Spectrum Disorder: A Real-World Analysis Using German Claims Data

Introduction

Neuromyelitis optica spectrum disorder (NMOSD) is a rare autoimmune disease of the central nervous system which causes recurrent relapses, resulting in blindness, paralysis, and spinal cord damage. This study sought to explore the real-world burden, treatment, and cost of NMOSD in Germany using claims data.

Methods

Our study consisted of a retrospective analysis of two anonymized health insurance datasets covering around 9 million patients in Germany from 01/01/2013 to 31/12/2019. NMOSD patients were identified using inpatient and outpatient International Classification of Diseases, Tenth Revision (ICD-10) diagnoses of neuromyelitis optica (NMO; G36.0) and relevant symptom codes. Active periods of disease were identified based on relapse events (including hospitalizations and acute treatment); healthcare resource utilization (HCRU) and direct costs were allocated to active and inactive periods based on treatment dates. Propensity score matching was used to compare HCRU and cost outcomes among patients with and without NMOSD.

Results

Overall, 130 patients were identified as having NMOSD (mean age: 46.84 years; 58% female). NMOSD patients recorded 16.52 active and 348.48 inactive days per patient year (PPY). HCRU and associated costs were approximately tenfold higher during active periods than during inactive periods, with the largest share of the cost difference driven by hospitalizations (€6424.09/€259.10 per active/inactive month) and outpatient drug prescriptions (€412.83/€271.58). Direct healthcare costs incurred by patients with NMOSD (€12,913.28 PPY) were approximately threefold higher than those incurred by patients without NMOSD (€4667.66 PPY). Costs of hospitalization (€6448.32/€1937.64 PPY) and outpatient prescriptions (€3335.67/€1037.64 PPY) contributed most strongly to the difference.

Conclusion

Patients with NMOSD consume substantial healthcare resources and incur heavy costs during active disease phases. This study captured direct measurable healthcare costs and likely underestimates the real societal/emotional burden on patients and their families. Nevertheless, prevention of acute relapses represents one compelling strategy to minimize the economic burden of NMOSD in Germany.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40120-021-00311-x.

Contingent intramuscular boosting of P2XR7 axis improves motor function in transgenic ALS mice

Amyotrophic lateral sclerosis is a fatal neurodegenerative disorder that leads to progressive degeneration of motor neurons and severe muscle atrophy without effective treatment. Most research on the disease has been focused on studying motor neurons and supporting cells of the central nervous system. Strikingly, the recent observations have suggested that morpho-functional alterations in skeletal muscle precede motor neuron degeneration, bolstering the interest in studying muscle tissue as a potential target for the delivery of therapies. We previously showed that the systemic administration of the P2XR7 agonist, 2′(3′)-O‐(4-benzoylbenzoyl) adenosine 5-triphosphate (BzATP), enhanced the metabolism and promoted the myogenesis of new fibres in the skeletal muscles of SOD1G93A mice. Here we further corroborated this evidence showing that intramuscular administration of BzATP improved the motor performance of ALS mice by enhancing satellite cells and the muscle pro-regenerative activity of infiltrating macrophages. The preservation of the skeletal muscle retrogradely propagated along with the motor unit, suggesting that backward signalling from the muscle could impinge on motor neuron death. In addition to providing the basis for a suitable adjunct multisystem therapeutic approach in ALS, these data point out that the muscle should be at the centre of ALS research as a target tissue to address novel therapies in combination with those oriented to the CNS.

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.

Randomized Controlled Trials for Neuromyelitis Optica Spectrum Disorder: A Review of Trial Architecture

BACKGROUND

Neuromyelitis optica spectrum disorder (NMOSD) is a relapsing inflammatory disease that primarily affects the optic nerves and the spinal cord. Randomized controlled trials (RCTs) assessing treatments for NMOSD have only been performed in the past decade, and to date, there are 3 drugs approved by the US Food and Drug Administration (FDA) for antiaquaporin-4 immunoglobulin G seropositive NMOSD. This review assesses the characteristics and challenges of RCTs when evaluating treatments for NMOSD.

REVIEW SUMMARY

We conducted a review using the terms ("neuromyelitis optica" OR "NMO" OR "NMOSD") AND "clinical trial" in any language on March 28, 2021. Seven RCTs were included, and the trials' architecture was analyzed and synthesized. Overall, 794 subjects were randomized [monoclonal antibody intervention group, n= 493 (62.1%), placebo, n=196 (24.7%), and active control, n=105 (13.2%)]; 709 (89.3%) were females; and 658 (82.9%) were aquaporin-4 (AQP4) antibody seropositive. The primary outcome was time to relapse in 6/7 of the trials, and annualized relapse rate in the remaining one. Four RCTs used placebo in their design. Among the seven published RCTs, the trial design differed by the criteria used to define NMOSD relapse, selection of subjects, proportion of AQP4 immunoglobulin G seronegative patients, and baseline characteristics indicating NMO disease severity.

CONCLUSIONS

Ethical considerations for the use of placebo should change in light of the approval of 3 therapies for seropositive NMOSD. Remaining challenges for clinical trials in NMOSD include the assessment of long-term safety and efficacy, standardization of trial design and endpoints, and head-to-head study designs.

Assessing attacks and treatment response rates among adult patients with NMOSD and MOGAD: Data from a nationwide registry in Argentina

We aimed to examine treatment interventions implemented in patients experiencing neuromyelitis optica spectrum disorders (NMOSD) attacks (frequency, types, and response).

Seasonal variation in autoimmune encephalitis: A multi-center retrospective study

OBJECTIVE

The aim of this study was to examine the seasonal distribution in clinical onset of autoimmune encephalitis (AE) in a multi-center cohort in China.

METHODS

This retrospective study consecutively recruited patients with new-onset definite neuronal surface antibody-associated AE between January 2015 and December 2020 from 3 tertiary hospitals. Demographic and clinical characteristics of the participants were comprehensively collected. Statistical analyses were performed using R.

RESULTS

Of the 184 patients of AE in our database, 149 (81.0%) were included in the final analysis. The median age of onset was 40.0 years, and 66 (44.3%) patients were female. AE predominantly started in autumn (47, 31.5%) and summer (43, 28.9%) months. Summer-autumn predominance of the clinical onsets was also present in the anti-N-methyl-d-aspartate receptor (NMDAR) encephalitis group (54, 60.0%) and anti-leucine-rich glioma inactivated 1 (LGI1) encephalitis group (20, 76.9%). No obvious seasonal variations were observed among gender, onset age, disease duration, prodromal symptoms, clinical type of initial symptoms, and disease severity by the time of admission.

CONCLUSION

This study suggested summer-autumn predominance of the clinical onsets in patients with AE, especially anti-NMDAR and anti-LGI1 encephalitis. Therefore, clinicians should have a high index of suspicion for AE in encephalopathy patients in summer and autumn period.

Magnetic resonance imaging in neuromyelitis optica spectrum disorder

Neuromyelitis optica spectrum disorder (NMOSD) is an inflammatory disease of the central nervous system (CNS) associated with antibodies to aquaporin-4 (AQP4), which has distinct clinical, radiological and pathological features, but also has some overlap with multiple sclerosis and myelin oligodendrocyte glycoprotein (MOG) antibody associated disease. Early recognition of NMOSD is important because of differing responses to both acute and preventive therapy. Magnetic resonance (MR) imaging has proved essential in this process. Key MR imaging clues to the diagnosis of NMOSD are longitudinally extensive lesions of the optic nerve (more than half the length) and spinal cord (three or more vertebral segments), bilateral optic nerve lesions and lesions of the optic chiasm, area postrema, floor of the IV ventricle, periaqueductal grey matter, hypothalamus and walls of the III ventricle. Other NMOSD-specific lesions are denoted by their unique morphology: heterogeneous lesions of the corpus callosum, 'cloud-like' gadolinium (Gd)-enhancing white matter lesions and 'bright spotty' lesions of the spinal cord. Other lesions described in NMOSD, including linear periventricular peri-ependymal lesions and patch subcortical white matter lesions, may be less specific. The use of advanced MR imaging techniques is yielding further useful information regarding focal degeneration of the thalamus and optic radiation in NMOSD and suggests that paramagnetic rim patterns and changes in normal appearing white matter are specific to MS. MR imaging is crucial in the early recognition of NMOSD and in directing testing for AQP4 antibodies and guiding immediate acute treatment decisions. Increasingly, MR imaging is playing a role in diagnosing seronegative cases of NMOSD.

Neuromyelitis optica spectrum disorders

The disease concept of Neuromyelitis Optica Spectrum Disorders(NMOSD) has undergone a significant change over the last two decades including the detection of Myelin Oligodendrocyte Glycoprotein(MOG) antibody in patients who are seronegative for aquaporin-4 antibody. Aquaporin-4 antibody positive NMOSD is now regarded as an immune astrocytopathy. Conversely, MOG antibody associated disease is known to target myelin rather than astrocytes, leading to an NMOSD syndrome with distinct clinical and radiological features. Incorporation of clinical features like area postrema syndrome, brainstem syndrome, diencephalic syndrome and cortical manifestations as core clinical characteristics into the revised diagnostic criteria has widened the clinical spectrum of NMOSD. With the development of these criteria, it is possible to make the diagnosis at an earlier stage so that effective immunosuppression can be instituted promptly for a better long-term prognosis. Newer therapeutic agents have been introduced for aquaporin-4 seropositive NMOSD disease; however, challenges remain in treating seronegative disease because of limited treatment options.

Seasonal variation of onset in patients with anti-aquaporin-4 antibodies and anti-myelin oligodendrocyte glycoprotein antibody

This study aimed to determine the seasonal impact on the clinical onset of inflammatory neurological diseases of the central nervous system by analyzing the onset month with information on clinical manifestations in Japanese patients. As a result, patients with anti-aquaporin-4 antibodies (AQP4-IgG)-positive neuromyelitis optica spectrum disorders (NMOSD) showed spring-summer predominance of the clinical onset. Conversely, patients with anti-myelin oligodendrocyte glycoprotein antibody (MOG-IgG)-associated disease showed autumn-winter predominance of the clinical onset. Both seasonal variations were irrespective of the clinical manifestation. Environmental factors with seasonal variation influence the development of neurological conditions related to AQP4-IgG and MOG-IgG.