Faculty Bibliography

BACKGROUND:In neuromyelitis optica spectrum disorder (NMOSD), clinical disability in NMOSD patients is relapse-related and progressive phase is rare. This observation raises the question whether there is any radiographic disease activity. The aim of present study was to determine the longitudinal changes in cerebral lesion number, lesion size, lesion-to-venule relationship, and morphological patterns of lesions in NMOSD using multiparametric 7T MR imaging. We also aimed to assess brain volume changes in NMOSD. METHODS:A cohort of 22 patients with NMOSD underwent high-resolution 3D-susceptibility weighted imaging (SWI) and 2D-gradient-echo (GRE-T2*) weighted imaging on 7T MRI of brain at baseline and after ~2.8 years of follow-up. Morphologic imaging characteristics, and signal intensity patterns of lesions were recorded at both time points. Lesions were classified as "iron-laden" if they demonstrated hypointense signal on GRE-T2* images and/or SWI as well as hyperintense signal on quantitative susceptibility mapping (QSM). Lesions were considered "non-iron-laden" if they were hyperintense on GRE-T2*/SWI and isointense or hyperintense on QSM. Additionally, fractional brain parenchymal volume (fBPV) was computed at both time points. RESULTS:A total of 169 lesions were observed at baseline. At follow-up, 6 new lesions were found in 5 patients. In one patient, a single lesion could not be detected on the follow-up scan. No appreciable change in lesion size and vessel-lesion relationship was observed at follow up. All lesions demonstrated hyperintense signal intensity on GRE-T2* weighted images and isointense signal on QSM at both time points. Therefore, these lesions were considered as non-associated with iron pathology. Additionally, no significant change in brain volume was observed: fBPV 0.78 ± 0.06 at baseline vs. 0.77 ± 0.05 at follow up, p>0.05. CONCLUSION/CONCLUSIONS:Cerebral lesions in NMOSD patients remain 'inert' and do not show any substantial variations in morphological characteristics during a 2-3-year follow-up period.

BACKGROUND:High-efficacy therapies in multiple sclerosis are traditionally used after unsuccessful treatment with first-line disease modifying therapies. We hypothesised that early commencement of high-efficacy therapy would be associated with reduced long-term disability. We therefore aimed to compare long-term disability outcomes between patients who started high-efficacy therapies within 2 years of disease onset with those who started 4-6 years after disease onset. METHODS:In this retrospective international observational study, we obtained data from the MSBase registry and the Swedish MS registry, which prospectively collect patient data that are specific to multiple sclerosis as part of routine clinical care. We identified adult patients (aged ≥18 years) with relapsing-remitting multiple sclerosis, with at least 6 years of follow-up since disease onset, and who started the high-efficacy therapy (rituximab, ocrelizumab, mitoxantrone, alemtuzumab, or natalizumab) either 0-2 years (early) or 4-6 years (late) after clinical disease onset. We matched patients in the early and late groups using propensity scores calculated on the basis of their baseline clinical and demographic data. The primary outcome was disability, measured with the Expanded Disability Status Score (EDSS; an ordinal scale of 0-10, with higher scores indicating increased disability), at 6-10 years after disease onset, assessed with a linear mixed-effects model. FINDINGS/RESULTS:We identified 6149 patients in the MSBase registry who had been given high-efficacy therapy, with data collected between Jan 1, 1975, and April 13, 2017, and 2626 patients in the Swedish MS Registry, with data collected between Dec 10, 1997, and Sept 16, 2019. Of whom, 308 in the MSBase registry and 236 in the Swedish MS registry were eligible for inclusion. 277 (51%) of 544 patients commenced therapy early and 267 (49%) commenced therapy late. For the primary analysis, we matched 213 patients in the early treatment group with 253 in the late treatment group. At baseline, the mean EDSS score was 2·2 (SD 1·2) in the early group and 2·1 (SD 1·2) in the late group. Median follow-up time for matched patients was 7·8 years (IQR 6·7-8·9). In the sixth year after disease onset, the mean EDSS score was 2·2 (SD 1·6) in the early group compared with 2·9 (SD 1·8) in the late group (p<0·0001). This difference persisted throughout each year of follow-up until the tenth year after disease onset (mean EDSS score 2·3 [SD 1·8] vs 3·5 [SD 2·1]; p<0·0001), with a difference between groups of -0·98 (95% CI -1·51 to -0·45; p<0·0001, adjusted for proportion of time on any disease-modifying therapy) across the 6-10 year follow-up period. INTERPRETATION/CONCLUSIONS:High-efficacy therapy commenced within 2 years of disease onset is associated with less disability after 6-10 years than when commenced later in the disease course. This finding can inform decisions regarding optimal sequence and timing of multiple sclerosis therapy. FUNDING/BACKGROUND:National Health and Medical Research Council Australia and MS Society UK.

OBJECTIVE:To determine if the concentration and saturation of natalizumab (NTZ) administration at extended interval dosing (EID; every 5-8 weeks) over 18 months is able to be maintained in the range considered adequate to sustain the clinical efficacy of NTZ. METHODS:-integrin receptor saturations were analyzed via cytometry, in blood samples obtained at trough timepoints. RESULTS:Trough serum concentration was above the "therapeutic" concentration of 2.0 μg/mL in 72% of EID patients. Trough saturation was above the "therapeutic" 50% threshold in 79% of EID-treated patients. Our model predicted that at least 9 NTZ infusions/year are required to maintain adequate trough saturation and concentration levels. Higher body mass index (BMI) was a predictor of suboptimal trough saturation on EID NTZ. CONCLUSIONS:Trough α4-integrin receptor saturation >50% correlated with high clinical efficacy of NTZ in previous studies. A continual treatment with EID maintains receptor saturation and concentration that are in the "therapeutic range" for most patients. This finding provides biological plausibility for the clinical efficacy of NTZ EID. Patients with higher BMI may require closer clinical and MRI follow-up.

BACKGROUND:Spinal epidural lipomatosis (SEL) is a rare condition defined as pathological overgrowth of the normally present epidural fat within the spinal canal. SEL is associated with Cushing disease, obesity and chronic corticosteroid therapy. Diabetes mellitus type 1 (DM1) has not known to be a risk factor for SEL. The neurological symptoms of SEL are attributed mainly to mechanical compression on the spinal cord and the cauda equina. METHODS:A retrospective chart review of patients evaluated at NYU Multiple Sclerosis Care Center identified three diabetic patients with progressive myelopathy associated with SEL. We report the clinical course, diagnostic workup and outcomes in these three patients with SEL-associated myelopathy. RESULTS:Three patients (2 females and 1 male) had long-standing DM1 and developed progressive myelopathy in their early 40's. All were found to have thoracic SEL (extensive extradural T1, T2 hyperintense signal; biopsy confirmed in one case) with associated extensive abnormal cord signal in lower cervical/upper thoracic spinal cord. A comprehensive evaluation for metabolic, infectious, autoimmune and vascular causes of myelopathy that included serologies, cerebrospinal fluid analyses, and spinal angiography did not reveal an alternative cause for myelopathy. One of the patients underwent a surgical decompression of SEL with subsequent clinical and radiologic improvement. CONCLUSIONS:Our case series suggest that patients with DM1 and myelopathy of unknown cause should be evaluated for SEL. Timely diagnosis and appropriate intervention may forestall progression of neurological disability and even result in neurologic improvement. SEL should be considered on the short list of diagnoses that cause potentially reversible progressive myelopathy.

Severity score represents disease duration-adjusted mean rank of disability in multiple sclerosis (MS) patients from the reference population. This measure allows one to compare the relative rates of disease progression among patients, patient subgroups, and across epochs, which opens up new question of what accounts for the observed differences in severity, and can be used to assess correlation between disease severity and clinical, radiologic, immunologic, genetic, and environmental variables of interest. Severity score can also prove useful for developing prognostic tools in MS. This article discusses the diverse applications of severity score concept in MS research, and (re)introduces Herbert's proposal of severity-based MS classification in the context of variability of MS severity.

Background: Natalizumab (NTZ) is a highly efficacious therapy for relapsing forms of multiple sclerosis (MS), but is associated with risk of progressive multifocal leukoencephalopathy (PML). A previous study demonstrated that extending NTZ dosing to every 35-43 days (EID) was associated with lower PML risk than the standard (every 28 days) dosing (SID). This finding raises the important question of whether NTZ should be administered as EID.
Method(s): MS patients receiving NTZ prior to May 31, 2018 at NYU (New York, NY) or Rocky Mountain (Salt Lake City, UT) MS centers were retrospectively identified. EID cohorts were defined similarly to definitions used for the previous PML risk study. For definition 1 (DEF 1), the last 18 months of treatment was considered (<=15 infusions in the last 18 months) while definition 3 (DEF 3) considered the entire infusion history (mean of <=10 infusions/year). Eligible patients were required to have >=24 months of treatment; >=1 MRI available for review; no gaps > 3 months on treatment; no infusions <= 21 days apart; and had no PML. Disease activity was identified by review of MRI radiology reports evaluating for presence of gadolinium (Gd) and new T2 lesions. Generalized Estimating Equation (GEE) logistic models and SAS 3.4 were used in the data analyses.
Result(s): 690 patients met the criteria. For DEF 1, no difference was observed between EID and SID in the odds of presence of Gd lesions (n=500) (OR/month increse 1.1; 95% CI 0.93, 1.31; p=0.27) or new T2 lesions (n=450) (OR/month increase 1.11; 95%CI 0.99, 1.24; p=0.07). Similarly, for DEF 3 no difference was observed between EID and SID in the odds of presence of Gd lesions (n =401) (OR/month increase1.00; 95%CI0.983, 1.025; p=0.75). There is a small increase in the odds of presence of new T2 lesions in EID group (n =437) (OR/month increase1.05; 95% CI 1.01, 1.10; p=0.02). GEE models included adjustments for the frequencies of MRIs for Gd lesions.
Conclusion(s): The study helps address a currently unmet need for evaluating EID NTZ efficacy. These findings suggest that EID of NTZ does not result in significant increased radiological MS disease activity compared to SID, providing further evidence that NTZ efficacy is comparable with EID