Don't be late! Postponing cognitive decline and preventing early unemployment in people with multiple sclerosis: a study protocol.

BACKGROUND: Up to 65% of people with multiple sclerosis (PwMS) develop cognitive deficits, which hampers their ability to work, participating in day-to-day life and ultimately reducing quality of life (QoL). Early cognitive symptoms are often less tangible to PwMS and their direct environment and are noticed only when symptoms and work functioning problems become more advanced, i.e., when (brain) damage is already advanced. Treatment of symptoms at a late stage can lead to cognitive impairment and unemployment, highlighting the need for preventative interventions in PwMS. AIMS: This study aims to evaluate the (cost-) effectiveness of two innovative preventative interventions, aimed at postponing cognitive decline and work functioning problems, compared to enhanced usual care in improving health-related QoL (HRQoL). METHODS: Randomised controlled trial including 270 PwMS with mild cognitive impairment, who have paid employment ≥ 12 h per week and are able to participate in physical exercise (Expanded Disability Status Scale < 6.0). Participants are randomised across three study arms: 1) 'strengthening the brain' - a lifestyle intervention combining personal fitness, mental coaching, dietary advice, and cognitive training; 2) 'strengthening the mind' - a work-focused intervention combining the capability approach and the participatory approach in one-on-one coaching by trained work coaches who have MS themselves; 3) Control group-receiving general information about cognitive impairment in MS and receiving care as usual. Intervention duration is four months, with short-term and long-term follow-up measurements at 10 and 16 months, respectively. The primary outcome measure of the Don't be late! intervention study will be HRQoL as measured with the 36-item Short Form. Secondary outcomes include cognition, work related outcomes, physical functioning, structural and functional brain changes, psychological functioning, and societal costs. Semi-structured interviews and focus groups with stakeholders will be organised to qualitatively reflect on the process and outcome of the interventions. DISCUSSION: This study seeks to prevent (further) cognitive decline and job loss due to MS by introducing tailor-made interventions at an early stage of cognitive symptoms, thereby maintaining or improving HRQoL. Qualitative analyses will be performed to allow successful implementation into clinical practice. TRIAL REGISTRATION: Retrospectively registered at ClinicalTrials.gov with reference number NCT06068582 on 10 October 2023.

Don't be late! Timely identification of cognitive impairment in people with multiple sclerosis: a study protocol.

BACKGROUND: Cognitive impairment occurs in up to 65% of people with multiple sclerosis (PwMS), negatively affecting daily functioning and health-related quality of life. In general, neuropsychological testing is not part of standard MS-care due to insufficient time and trained personnel. Consequently, a baseline assessment of cognitive functioning is often lacking, hampering early identification of cognitive decline and change within a person over time. To assess cognitive functioning in PwMS in a time-efficient manner, a BICAMS-based self-explanatory digital screening tool called the Multiple Screener©, has recently been developed. The aim of the current study is to validate the Multiple Screener© in a representative sample of PwMS in the Netherlands. Additionally, we aim to investigate how cognitive functioning is related to psychological factors, and both work and societal participation. METHODS: In this cross-sectional multicentre study, 750 PwMS (aged 18-67 years) are included. To obtain a representative sample, PwMS are recruited via 12 hospitals across the Netherlands. They undergo assessment with the Minimal Assessment of Cognitive Functioning in MS (MACFIMS; reference-standard) and the Multiple Screener©. Sensitivity, specificity, and predictive values for identifying (mild) cognitive impairment are determined in a subset of 300 participants. In a second step, the identified cut-off values are tested in an independent subset of at least 150 PwMS. Moreover, test-retest reliability for the Multiple Screener© is determined in 30 PwMS. Information on psychological and work-related factors is assessed with questionnaires. DISCUSSION: Validating the Multiple Screener© in PwMS and investigating cognition and its determinants will further facilitate early identification and adequate monitoring of cognitive decline in PwMS.

A novel eye-movement impairment in multiple sclerosis indicating widespread cortical damage.

In multiple sclerosis, remyelination trials have yet to deliver success like that achieved for relapse rates with disease course modifying treatment trials. The challenge is to have a clinical, functional outcome measure. Currently, there are none that have been validated, other than visual evoked potentials in optic neuritis. Like vision, quick eye movements (saccades) are heavily dependent on myelination. We proposed that it is possible to extrapolate from demyelination of the medial longitudinal fasciculus in the brainstem to quantitative assessment of cortical networks governing saccadic eye movements in multiple sclerosis. We have developed and validated a double-step saccadic test, which consists of a pair of eye movements towards two stimuli presented in quick succession (the demonstrate eye movement networks with saccades protocol). In this single-centre, cross-sectional cohort study we interrogated the structural and functional relationships of double-step saccades in multiple sclerosis. Data were collected for double-step saccades, cognitive function (extended Rao's Brief Repeatable Battery), disability (Expanded Disability Status Scale) and visual functioning in daily life (National Eye Institute Visual Function Questionnaire). MRI was used to quantify grey matter atrophy and multiple sclerosis lesion load. Multivariable linear regression models were used for analysis of the relationships between double-step saccades and clinical and MRI metrics. We included 209 individuals with multiple sclerosis (mean age 54.3 ± 10.5 years, 58% female, 63% relapsing-remitting multiple sclerosis) and 60 healthy control subjects (mean age 52.1 ± 9.2 years, 53% female). The proportion of correct double-step saccades was significantly reduced in multiple sclerosis (mean 0.29 ± 0.22) compared to controls (0.45 ± 0.22, P < 0.001). Consistent with this, there was a significantly larger double-step dysmetric saccadic error in multiple sclerosis (mean vertical error -1.18 ± 1.20°) compared to controls (-0.54 ± 0.86°, P < 0.001). Impaired double-step saccadic metrics were consistently associated with more severe global and local grey matter atrophy (correct responses-cortical grey matter: ß = 0.42, P < 0.001), lesion load (vertical error: ß = -0.28, P < 0.001), progressive phenotypes, more severe physical and cognitive impairment (correct responses-information processing: ß = 0.46, P < 0.001) and visual functioning. In conclusion, double-step saccades represent a robust metric that revealed a novel eye-movement impairment in individuals with multiple sclerosis. Double-step saccades outperformed other saccadic tasks in their statistical relationship with clinical, cognitive and visual functioning, as well as global and local grey matter atrophy. Double-step saccades should be evaluated longitudinally and tested as a potential novel outcome measure for remyelination trials in multiple sclerosis.

The association between weight during early life and multiple sclerosis onset in a nationwide Dutch birth year cohort.

BACKGROUND: The relationship between being overweight during early life and disease course in multiple sclerosis (MS) is unresolved. We investigated the association between being overweight or obese during early life (childhood and adolescence) and MS case status, age of first symptom onset and onset type in people with MS (pwMS) of the same birth year. METHODS: We enrolled 363 PwMS and 125 healthy controls (HC) from Project Y, a Dutch population-based cross-sectional cohort study including all PwMS born in 1966 and age and sex-matched HC. The associations between weight during childhood and adolescence (non-overweight vs. overweight or obese) and MS, age at symptom onset and onset type (relapsing vs. progressive) were assessed using logistic and linear regressions. In addition, sex-separated associations were explored. RESULTS: Being overweight or obese during childhood (OR = 2.82, 95% CI 1.17-6.80) and adolescence (OR = 2.45, 95% CI 1.13-5.34) was associated with developing MS. Furthermore, being overweight or obese during adolescence was associated with a younger age of onset (ß = -0.11, p = 0.041). Of all 47 patients with a primary progressive (PP) onset type, only one patient (2.1%) was overweight or obese during childhood, whereas 45 patients with a relapsing remitting (RR) onset (14.3%) were overweight or obese during childhood (PP vs. RR p = 0.017; PP vs. HC p = 0.676; RR vs. HC, p = 0.015). However, using logistic regression analysis we did not find evidence of a significant association. CONCLUSION: In a nationwide population-based birth year cohort, being overweight or obese during childhood or adolescence is associated with MS prevalence and an earlier age of onset, but does not seem to associate with the type of onset.

Extended interval dosing of ocrelizumab modifies the repopulation of B cells without altering the clinical efficacy in multiple sclerosis.

BACKGROUND: Recent studies suggest that extended interval dosing of ocrelizumab, an anti-B cell therapy, does not affect its clinical effectiveness in most patients with multiple sclerosis (MS). However, it remains to be established whether certain B cell subsets are differentially repopulated after different dosing intervals and whether these subsets relate to clinical efficacy. METHODS: We performed high-dimensional single-cell characterization of the peripheral immune landscape of patients with MS after standard (SID; n = 43) or extended interval dosing (EID; n = 37) of ocrelizumab and in non-ocrelizumab-treated (control group, CG; n = 28) patients with MS, using mass cytometry by time of flight (CyTOF). RESULTS: The first B cells that repopulate after both ocrelizumab dosing schemes were immature, transitional and regulatory CD1d+ CD5+ B cells. In addition, we observed a higher percentage of transitional, naïve and regulatory B cells after EID in comparison with SID, but not of memory B cells or plasmablasts. The majority of repopulated B cell subsets showed an increased migratory phenotype, characterized by higher expression of CD49d, CD11a, CD54 and CD162. Interestingly, after EID, repopulated B cells expressed increased CD20 levels compared to B cells in CG and after SID, which was associated with a delayed repopulation of B cells after a subsequent ocrelizumab infusion. Finally, the number of/changes in B cell subsets after both dosing schemes did not correlate with any relapses nor progression of the disease. CONCLUSIONS: Taken together, our data highlight that extending the dosing interval of ocrelizumab does not lead to increased repopulation of effector B cells. We show that the increase of CD20 expression on B cell subsets in EID might lead to longer depletion or less repopulation of B cells after the next infusion of ocrelizumab. Lastly, even though extending the ocrelizumab interval dosing alters B cell repopulation, it does not affect the clinical efficacy of ocrelizumab in our cohort of patients with MS.

Decrease of natalizumab drug levels after switching from intravenous to subcutaneous administration in patients with multiple sclerosis.

BACKGROUND: Natalizumab is effective in the treatment of multiple sclerosis (MS). In 2021, the European Medicines Agency approved the subcutaneous (SC) variant of natalizumab which can be used instead of intravenous administration. However, the course of drug levels varies between administration routes, and the Food and Drug Administration rejected the request for approval of natalizumab SC for reasons that were not disclosed. Our objective was to evaluate the course of natalizumab trough drug levels in patients who switched from natalizumab intravenous to SC on various treatment intervals. METHODS: The NEXT-MS trial (N=382) investigates personalised treatment of natalizumab, in which infusion intervals are prolonged based on individual natalizumab trough drug levels. In 2021, an amendment was approved allowing participants to switch from intravenous to SC administration with frequent measurements of natalizumab drug levels and antidrug antibodies (ADAs). Results were compared with linear mixed model analyses. RESULTS: Until December 2022, 15 participants switched to SC natalizumab. Natalizumab drug levels with SC administration were on average 55% lower compared with intravenous administration (Exp (estimate) 0.45, 95% CI 0.39 to 0.53, p<0.001), leading to very low trough drug levels in three patients on extended treatment intervals. No natalizumab ADAs were detected during intravenous or SC treatment. None of the participants on natalizumab SC showed evidence of MS disease activity. CONCLUSIONS: Natalizumab trough drug levels can decrease after switching from natalizumab intravenous to SC administration. We advise to monitor trough drug levels in patients with low natalizumab drug levels during intravenous treatment, patients with higher body mass index or patients on extended treatment intervals who switch to SC administration of natalizumab.

Ocrelizumab concentration and antidrug antibodies are associated with B-cell count in multiple sclerosis.

BACKGROUND: The majority of patients with multiple sclerosis on ocrelizumab have B-cell depletion after standard interval dosing of 26 weeks. With B-cell-guided dosing patients receive their next dose when B-cell repopulation occurs. Prediction of B-cell repopulation using ocrelizumab concentrations could aid in personalising treatment regimes. The objectives of this study were to evaluate the association between ocrelizumab drug concentration, antidrug antibodies (ADAs) and CD19 B-cell count, and to define a cut-off ocrelizumab concentration for start of B-cell repopulation (defined by ≥10 CD19+ B cells/µL). METHODS: In this investigator-initiated prospective study, blood samples at various time points during ocrelizumab treatment were collected from a biobank. Serum ocrelizumab concentrations and ADAs were measured with two different assays developed for this study. Data were analysed using linear mixed effect models. An receiver operating characteristic (ROC) curve was used to determine a cut-off ocrelizumab concentration for start of B-cell repopulation (defined by ≥10 cells/µL). RESULTS: A total of 452 blood samples from 72 patients were analysed. Ocrelizumab concentrations were detectable up until 53.3 weeks after last infusion and ranged between <0.0025 and 204 µg/mL after 1-67 weeks. Ocrelizumab concentration was negatively associated with B-cell count, with body mass index identified as effect modifier. We found a cut-off value of 0.06 µg/mL for start of B-cell repopulation of ≥10 cells/µL. Ocrelizumab ADAs were detectable in four patients (5.7%) with corresponding low ocrelizumab concentrations and start of B-cell repopulation. CONCLUSIONS: Serum ocrelizumab concentration was strongly associated with B-cell count. Measurement of ocrelizumab drug concentrations and ADAs could play an important role to further personalise treatment and predict the start of B-cell repopulation.

Evolution from a first clinical demyelinating event to multiple sclerosis in the REFLEX trial: Regional susceptibility in the conversion to multiple sclerosis at disease onset and its amenability to subcutaneous interferon beta-1a.

BACKGROUND AND PURPOSE: In the REFLEX trial (ClinicalTrials.gov identifier: NCT00404352), patients with a first clinical demyelinating event (FCDE) displayed significantly delayed onset of multiple sclerosis (MS; McDonald criteria) when treated with subcutaneous interferon beta-1a (sc IFN ß-1a) versus placebo. This post hoc analysis evaluated the effect of sc IFN ß-1a on spatio-temporal evolution of disease activity, assessed by changes in T2 lesion distribution, in specific brain regions of such patients and its relationship with conversion to MS. METHODS: Post hoc analysis of baseline and 24-month magnetic resonance imaging data from FCDE patients who received sc IFN ß-1a 44 µg once or three times weekly, or placebo in the REFLEX trial. Patients were grouped according to McDonald MS status (converter/non-converter) or treatment (sc IFN ß-1a/placebo). For each patient group, a baseline lesion probability map (LPM) and longitudinal new/enlarging and shrinking/disappearing LPMs were created. Lesion location/frequency of lesion occurrence were assessed in the white matter. RESULTS: At Month 24, lesion frequency was significantly higher in the anterior thalamic radiation (ATR) and corticospinal tract (CST) of converters versus non-converters (p < 0.05). Additionally, the overall distribution of new/enlarging lesions across the brain at Month 24 was similar in placebo- and sc IFN ß-1a-treated patients (ratio: 0.95). Patients treated with sc IFN ß-1a versus placebo showed significantly lower new lesion frequency in specific brain regions (cluster corrected): ATR (p = 0.025), superior longitudinal fasciculus (p = 0.042), CST (p = 0.048), and inferior longitudinal fasciculus (p = 0.048). CONCLUSIONS: T2 lesion distribution in specific brain locations predict conversion to McDonald MS and show significantly reduced new lesion occurrence after treatment with sc IFN ß-1a in an FCDE population.

Longitudinal Development of Peripapillary Hyper-Reflective Ovoid Masslike Structures Suggests a Novel Pathological Pathway in Multiple Sclerosis.

OBJECTIVE: Peripapillary hyper-reflective ovoid masslike structures (PHOMS) are a new spectral domain optical coherence tomography (OCT) finding. METHODS: This prospective, longitudinal study included patients (n = 212) with multiple sclerosis (MS; n = 418 eyes), 59 healthy controls (HCs; n = 117 eyes), and 267 non-MS disease controls (534 eyes). OCT and diffusion tensor imaging were used. RESULTS: There were no PHOMS in HC eyes (0/117, 0%). The prevalence of PHOMS was significantly higher in patients with MS (34/212, p = 0.001) and MS eyes (45/418, p = 0.0002) when compared to HCs (0/59, 0/117). The inter-rater agreement for PHOMS was 97.9% (kappa = 0.951). PHOMS were present in 16% of patients with relapsing-remitting, 16% of patients with progressive, and 12% of patients with secondary progressive disease course (2% of eyes). There was no relationship of PHOMS with age, disease duration, disease course, disability, or disease-modifying treatments. The fractional anisotropy of the optic radiations was lower in patients without PHOMS (0.814) when compared to patients with PHOMS (0.845, p = 0.03). The majority of PHOMS remained stable, but increase in size and de novo development of PHOMS were also observed. In non-MS disease controls, PHOMS were observed in intracranial hypertension (62%), optic disc drusen (47%), anomalous optic discs (44%), isolated optic neuritis (19%), and optic atrophy (12%). INTERPRETATION: These data suggest that PHOMS are a novel finding in MS pathology. Future research is needed to determine whether development of PHOMS in MS is due to intermittently raised intracranial pressure or an otherwise impaired "glymphatic" outflow from eye to brain. ANN NEUROL 2020;88:309-319.

Longitudinal Assessment of Multiple Sclerosis with the Brain-Age Paradigm.

OBJECTIVE: During the natural course of multiple sclerosis (MS), the brain is exposed to aging as well as disease effects. Brain aging can be modeled statistically; the so-called "brain-age" paradigm. Here, we evaluated whether brain-predicted age difference (brain-PAD) was sensitive to the presence of MS, clinical progression, and future outcomes. METHODS: In a longitudinal, multicenter sample of 3,565 magnetic resonance imaging (MRI) scans, in 1,204 patients with MS and clinically isolated syndrome (CIS) and 150 healthy controls (mean follow-up time: patients 3.41 years, healthy controls 1.97 years), we measured "brain-predicted age" using T1-weighted MRI. We compared brain-PAD among patients with MS and patients with CIS and healthy controls, and between disease subtypes. Relationships between brain-PAD and Expanded Disability Status Scale (EDSS) were explored. RESULTS: Patients with MS had markedly higher brain-PAD than healthy controls (mean brain-PAD +10.3 years; 95% confidence interval [CI] = 8.5-12.1] versus 4.3 years; 95% CI = 2.1 to 6.4; p < 0.001). The highest brain-PADs were in secondary-progressive MS (+13.3 years; 95% CI = 11.3-15.3). Brain-PAD at study entry predicted time-to-disability progression (hazard ratio 1.02; 95% CI = 1.01-1.03; p < 0.001); although normalized brain volume was a stronger predictor. Greater annualized brain-PAD increases were associated with greater annualized EDSS score (r = 0.26; p < 0.001). INTERPRETATION: The brain-age paradigm is sensitive to MS-related atrophy and clinical progression. A higher brain-PAD at baseline was associated with more rapid disability progression and the rate of change in brain-PAD related to worsening disability. Potentially, "brain-age" could be used as a prognostic biomarker in early-stage MS, to track disease progression or stratify patients for clinical trial enrollment. ANN NEUROL 2020 ANN NEUROL 2020;88:93-105.

A model for interrogating the clinico-radiological paradox in multiple sclerosis: Internuclear ophthalmoplegia.

BACKGROUND AND PURPOSE: The clinico-radiological paradox in multiple sclerosis (MS) is well recognized, relevant and yet poorly understood. The suitability of an in vivo model for the clinico-radiological paradox was tested, using internuclear ophthalmoplegia (INO) and the medial longitudinal fasciculus (MLF). METHODS: In this cross-sectional study lesions of the MLF were rated by an experienced MS neuroradiologist blinded to all other information. The presence of an INO was objectively determined by a validated infrared oculography protocol (DEMoNS). Clinical information, including the National Eye Institute Visual Function Questionnaire, was obtained. RESULTS: This study included 202 patients with MS. The clinico-radiological paradox occurred in 50 patients (25%). This consisted of 45 patients having an INO without an MLF lesion and five patients with an MLF lesion but without an INO. The visual function overall score was related to the presence of an INO (p = 0.016), but not to MLF lesions seen on magnetic resonance imaging (MRI) (p = 0.207). A consensus list of potential causes for the clinico-radiological paradox was compiled and the MRI images were deposited in a repository. CONCLUSION: This study provides an objective and quantitative model to investigate the clinico-radiological paradox. Our data suggest that pathology of the MLF is more frequently detected and more clinically relevant by infrared oculography than by MLF lesion rating on MRI.

Development of an EORTC questionnaire measuring instrumental activities of daily living (IADL) in patients with brain tumours: phase I-III.

PURPOSE: Being able to function independently in society is an important aspect of quality of life. This ability goes beyond self-care, requires higher order cognitive functioning, and is typically measured with instrumental activities of daily living (IADL) questionnaires. Cognitive deficits are frequently observed in brain tumour patients, however, IADL is almost never assessed because no valid and reliable IADL measure is available for this patient group. Therefore, this measure is currently being developed. METHODS: This international multicentre study followed European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life Group module development guidelines. Three out of four phases are completed: phases (I) generation of items, (II) construction of the item list, and (III) pre-testing. This paper reports the item selection procedures and preliminary psychometric properties of the questionnaire. Brain tumour patients (gliomas and brain metastases), their informal caregivers, and health care professionals (HCPs) were included. RESULTS: Phase I (n = 44 patient-proxy dyads and 26 HCPs) generated 59 relevant and important activities. In phase II, the activities were converted into items. In phase III (n = 85 dyads), the 59 items were pre-tested. Item selection procedures resulted in 32 items. Exploratory factor analysis revealed a preliminary dimensional structure consisting of five scales with acceptable to excellent internal consistency (α = 0.73-0.94) and two single items. For three scales, patients with cognitive impairments had significantly more IADL problems than patients without impairments. CONCLUSION: A phase IV validation study is needed to confirm the psychometric properties of the EORTC IADL-BN32 questionnaire in a larger international sample.

Autoencoder as a New Method for Maintaining Data Privacy While Analyzing Videos of Patients With Motor Dysfunction: Proof-of-Concept Study.

BACKGROUND: In chronic neurological diseases, especially in multiple sclerosis (MS), clinical assessment of motor dysfunction is crucial to monitor the disease in patients. Traditional scales are not sensitive enough to detect slight changes. Video recordings of patient performance are more accurate and increase the reliability of severity ratings. When these recordings are automated, quantitative disability assessments by machine learning algorithms can be created. Creation of these algorithms involves non-health care professionals, which is a challenge for maintaining data privacy. However, autoencoders can address this issue. OBJECTIVE: The aim of this proof-of-concept study was to test whether coded frame vectors of autoencoders contain relevant information for analyzing videos of the motor performance of patients with MS. METHODS: In this study, 20 pre-rated videos of patients performing the finger-to-nose test were recorded. An autoencoder created encoded frame vectors from the original videos and decoded the videos again. The original and decoded videos were shown to 10 neurologists at an academic MS center in Basel, Switzerland. The neurologists tested whether the 200 videos were human-readable after decoding and rated the severity grade of each original and decoded video according to the Neurostatus-Expanded Disability Status Scale definitions of limb ataxia. Furthermore, the neurologists tested whether ratings were equivalent between the original and decoded videos. RESULTS: In total, 172 of 200 (86.0%) videos were of sufficient quality to be ratable. The intrarater agreement between the original and decoded videos was 0.317 (Cohen weighted kappa). The average difference in the ratings between the original and decoded videos was 0.26, in which the original videos were rated as more severe. The interrater agreement between the original videos was 0.459 and that between the decoded videos was 0.302. The agreement was higher when no deficits or very severe deficits were present. CONCLUSIONS: The vast majority of videos (172/200, 86.0%) decoded by the autoencoder contained clinically relevant information and had fair intrarater agreement with the original videos. Autoencoders are a potential method for enabling the use of patient videos while preserving data privacy, especially when non-health-care professionals are involved.

Natural History of Vanishing White Matter.

OBJECTIVE: To comprehensively describe the natural history of vanishing white matter (VWM), aiming at improving counseling of patients/families and providing natural history data for future therapeutic trials. METHODS: We performed a longitudinal multicenter study among 296 genetically confirmed VWM patients. Clinical information was obtained via disease-specific clinical questionnaire, Health Utilities Index and Guy's Neurological Disability Scale assessments, and chart review. RESULTS: First disease signs occurred at a median age of 3 years (mode = 2 years, range = before birth to 54 years); 60% of patients were symptomatic before the age of 4 years. The nature of the first signs varied for different ages of onset. Overall, motor problems were the most common presenting sign, especially in children. Adolescent and adult onset patients were more likely to exhibit cognitive problems early after disease onset. One hundred two patients were deceased. Multivariate Cox regression analysis revealed a positive relation between age at onset and both preservation of ambulation and survival. Absence of stress-provoked episodes and absence of seizures predicted more favorable outcome. In patients with onset before 4 years, earlier onset was associated with more severe disability and higher mortality. For onset from 4 years on, disease course was generally milder, with a wide variation in severity. There were no significant differences for sex or for the 5 eIF2B gene groups. The results confirm the presence of a genotype-phenotype correlation. INTERPRETATION: The VWM disease spectrum consists of a continuum with extremely wide variability. Age at onset is a strong predictor for disease course. Ann Neurol 2018;84:274-288.

Performance of PML diagnostic criteria in natalizumab-associated PML: data from the Dutch-Belgian cohort.

OBJECTIVE: To test the current progressive multifocal leukoencephalopathy (PML) diagnostic criteria by applying them to patients previously diagnosed with natalizumab (NTZ)-associated PML in a real-world clinical setting. METHODS: Patients from the Dutch-Belgian NTZ-PML cohort (n=28) were reviewed at the time of first diagnostic work-up and during follow-up, using the PML diagnostic criteria as proposed in a consensus statement from the American Academy of Neurology. RESULTS: At first diagnostic work-up, 18 patients (64.3%) met the criteria for high diagnostic certainty for PML ('definite PML' or 'probable PML'). During follow-up, this increased to 20 patients (71.4%) as JC virus DNA was detected in cerebrospinal fluid of two additional patients. Nonetheless, 28.6% of patients were still classified as 'possible PML' or 'not PML' (6 (21.5%) and 2 (7.1%) patients, respectively) despite a very high suspicion for PML based on lesion evolution and signs of PML-immune reconstitution inflammatory syndrome on MRI, and development of compatible symptoms. CONCLUSIONS: The current case definition of PML has low sensitivity for diagnosis of NTZ-PML in a real-world clinical setting in which MRI is frequently used for PML screening. This may delay diagnosis and appropriate management of PML, and may complicate a valid estimation of PML incidence during NTZ therapy.

Evaluation of the content coverage of questionnaires containing basic and instrumental activities of daily living (ADL) used in adult patients with brain tumors.

BACKGROUND: Everyday functioning can be assessed using measures of basic activities of daily living (BADL) or instrumental activities of daily living (IADL). The aim of this review was to provide an overview of the scope and specific content of BADL and/or IADL covered by currently used questionnaires in adult brain tumor patient studies. METHODS: Electronic databases were searched up to April 2017 to identify all eligible questionnaires with items regarding BADL/IADL in studies with adult brain tumor patients. Articles were selected using predetermined in- and exclusion criteria. Items with similar content were clustered into domains based on type of activity. RESULTS: Thirty-one unique questionnaires containing at least one BADL and/or IADL item were identified; 21 and 29 questionnaires containing ≥ 1 BADL or IADL item, respectively. The percentage of ADL items in these questionnaires ranged from 4 to 100%. Only two questionnaires were specifically developed to measure BADL (Barthel Index and Katz-ADL) and two specifically for IADL (Lawton-Brody IADL and preliminary IADL-BN). Content clustering revealed that IADL had a larger variation in content (31 domains, e.g. work or leisure time activities) compared to BADL (15 domains, e.g. mobility or bathing/washing). CONCLUSION: Thirty-one questionnaires previously used in brain tumor studies contained items on BADL and/or IADL and covered a wide range of content, in particular for IADL. It is currently unclear which BADL/IADL are most relevant for brain tumor patients, and this should therefore be evaluated. Next, existing questionnaires could be adapted or validated, or new measures can be developed to meet these needs.

Predicting cognitive decline in multiple sclerosis: a 5-year follow-up study.

Cognitive decline is common in multiple sclerosis and strongly affects overall quality of life. Despite the identification of cross-sectional MRI correlates of cognitive impairment, predictors of future cognitive decline remain unclear. The objective of this study was to identify which MRI measures of structural damage, demographic and/or clinical measures at baseline best predict cognitive decline, during a 5-year follow-up period. A total of 234 patients with clinically definite multiple sclerosis and 60 healthy control subjects were examined twice, with a 5-year interval (mean = 4.9 years, standard deviation = 0.9). An extensive neuropsychological evaluation was performed at both time points and the reliable change index was computed to evaluate cognitive decline. Both whole-brain and regional MRI (3 T) measures were assessed at baseline, including white matter lesion volume, diffusion-based white matter integrity, cortical and deep grey matter volume. Logistic regression analyses were performed to determine which baseline measures best predicted cognitive decline in the entire sample as well as in early relapsing-remitting (symptom duration <10 years), late relapsing-remitting (symptom duration ≥10 years) and progressive phenotypes. At baseline, patients with multiple sclerosis had a mean disease duration of 14.8 (standard deviation = 8.4) years and 96/234 patients (41%) were classified as cognitively impaired. A total of 66/234 patients (28%) demonstrated cognitive decline during follow-up, with higher frequencies in progressive compared to relapsing-remitting patients: 18/33 secondary progressive patients (55%), 10/19 primary progressive patients (53%) and 38/182 relapsing-remitting patients (21%). A prediction model that included only whole-brain MRI measures (Nagelkerke R2 = 0.22, P < 0.001) showed cortical grey matter volume as the only significant MRI predictor of cognitive decline, while a prediction model that assessed regional MRI measures (Nagelkerke R2 = 0.35, P < 0.001) indicated integrity loss of the anterior thalamic radiation, lesions in the superior longitudinal fasciculus and temporal atrophy as significant MRI predictors for cognitive decline. Disease stage specific regressions showed that cognitive decline in early relapsing-remitting multiple sclerosis was predicted by white matter integrity damage, while cognitive decline in late relapsing-remitting and progressive multiple sclerosis was predicted by cortical atrophy. These results indicate that patients with more severe structural damage at baseline, and especially cortical atrophy, are more prone to suffer from cognitive decline. New studies now need to further elucidate the underlying mechanisms leading to cortical atrophy, evaluate the value of including cortical atrophy as a possible outcome marker in clinical trials as well as study its potential use in individual patient management.

Explaining the heterogeneity of functional connectivity findings in multiple sclerosis: An empirically informed modeling study.

To understand the heterogeneity of functional connectivity results reported in the literature, we analyzed the separate effects of grey and white matter damage on functional connectivity and networks in multiple sclerosis. For this, we employed a biophysical thalamo-cortical model consisting of interconnected cortical and thalamic neuronal populations, informed and amended by empirical diffusion MRI tractography data, to simulate functional data that mimic neurophysiological signals. Grey matter degeneration was simulated by decreasing within population connections and white matter degeneration by lowering between population connections, based on lesion predilection sites in multiple sclerosis. For all simulations, functional connectivity and functional network organization are quantified by phase synchronization and network integration, respectively. Modeling results showed that both cortical and thalamic grey matter damage induced a global increase in functional connectivity, whereas white matter damage induced an initially increased connectivity followed by a global decrease. Both white and especially grey matter damage, however, induced a decrease in network integration. These empirically informed simulations show that specific topology and timing of structural damage are nontrivial aspects in explaining functional abnormalities in MS. Insufficient attention to these aspects likely explains contradictory findings in multiple sclerosis functional imaging studies so far.

Inflammatory natalizumab-associated PML: baseline characteristics, lesion evolution and relation with PML-IRIS.

BACKGROUND AND OBJECTIVE: Natalizumab-associated progressive multifocal leukoencephalopathy (NTZ-PML) patients may show imaging signs suggestive of inflammation at diagnosis ('inflammatory PML'), reminiscent of PML-immune reconstitution inflammatory syndrome (PML-IRIS). We investigated the imaging characteristics of inflammatory NTZ-PML lesions and PML-IRIS to determine differentiating and overlapping features. METHODS: We scored the presence, localisation and pattern of imaging characteristics of inflammation on brain MRI scans of inflammatory NTZ-PML patients. The imaging characteristics were followed up until the occurrence of PML-IRIS. RESULTS: Ten out of the 44 NTZ-PML patients included showed signs suggestive of inflammation at the time of diagnosis. The inflammation pattern at diagnosis was similar to the pattern seen at PML-IRIS, with contrast enhancement representing the most frequent sign of inflammation (90% at diagnosis, 100% at PML-IRIS). However, the severity of inflammation differed, with absence of swelling and low frequency of perilesional oedema (10%) at diagnosis, as compared with the PML-IRIS stage (40%). CONCLUSION: Patterns of inflammation at the time of PML diagnosis and at the PML-IRIS stage overlap but differ in their severity of inflammation. This supports histopathological evidence that the inflammation seen at both stages of the same disease shares a similar underlying pathophysiology, representing the immune response to the JC virus to a variable extend.