IMPORTANCE: Progression independent of relapse activity (PIRA) is a significant contributor to long-term disability accumulation in relapsing-remitting multiple sclerosis (MS). Prior studies have used varying PIRA definitions, hampering the comparability of study results. OBJECTIVE: To compare various definitions of PIRA. DESIGN, SETTING, AND PARTICIPANTS: This cohort study involved a retrospective analysis of prospectively collected data from the MSBase registry from July 2004 to July 2023. The participants were patients with MS from 186 centers across 43 countries who had clinically definite relapsing-remitting MS, a complete minimal dataset, and 3 or more documented Expanded Disability Status Scale (EDSS) assessments. EXPOSURE: Three-hundred sixty definitions of PIRA as combinations of the following criteria: baseline disability (fixed baseline with re-baselining after PIRA, or plus re-baselining after relapses, or plus re-baselining after improvements), minimum confirmation period (6, 12, or 24 months), confirmation magnitude (EDSS score at/above worsening score or at/above threshold compared with baseline), freedom from relapse at EDSS score worsening (90 days prior, 90 days prior and 30 days after, 180 days prior and after, since previous EDSS assessment, or since baseline), and freedom from relapse at confirmation (30 days prior, 90 days prior, 30 days before and after, or between worsening and confirmation). MAIN OUTCOME AND MEASURE: For each definition, we quantified PIRA incidence and persistence (ie, absence of a 3-month confirmed EDSS improvement over ≥5 years). RESULTS: Among 87 239 patients with MS, 33 303 patients fulfilled the inclusion criteria; 24 152 (72.5%) were female and 9151 (27.5%) were male. At the first visits, the mean (SD) age was 36.4 (10.9) years; 28 052 patients (84.2%) had relapsing-remitting MS, and the median (IQR) EDSS score was 2.0 (1.0-3.0). Participants had a mean (SD) 15.1 (11.9) visits over 8.9 (5.2) years. PIRA incidence ranged from 0.141 to 0.658 events per decade and persistence from 0.753 to 0.919, depending on the definition. In particular, the baseline and confirmation period influenced PIRA detection. The following definition yielded balanced incidence and persistence: a significant disability worsening compared with a baseline (reset after each PIRA event, relapse, and EDSS score improvement), in absence of relapses since the last EDSS assessment, confirmed with EDSS scores (not preceded by relapses within 30 days) that remained above the worsening threshold for at least 12 months. CONCLUSION AND RELEVANCE: Incidence and persistence of PIRA are determined by the definition used. The proposed standardized definition aims to enhance comparability among studies.

• MeSH
• dospělí MeSH
• kohortové studie MeSH
• lidé středního věku MeSH
• lidé MeSH
• posuzování pracovní neschopnosti MeSH
• progrese nemoci * MeSH
• recidiva MeSH
• registrace MeSH
• relabující-remitující roztroušená skleróza * diagnóza   patofyziologie   MeSH
• retrospektivní studie MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• multicentrická studie MeSH

BACKGROUND: Prognostic machine learning research in multiple sclerosis has been mainly focusing on black-box models predicting whether a patients' disability will progress in a fixed number of years. However, as this is a binary yes/no question, it cannot take individual disease severity into account. Therefore, in this work we propose to model the time to disease progression instead. Additionally, we use explainable machine learning techniques to make the model outputs more interpretable. METHODS: A preprocessed subset of 29,201 patients of the international data registry MSBase was used. Disability was assessed in terms of the Expanded Disability Status Scale (EDSS). We predict the time to significant and confirmed disability progression using random survival forests, a machine learning model for survival analysis. Performance is evaluated on a time-dependent area under the receiver operating characteristic and the precision-recall curves. Importantly, predictions are then explained using SHAP and Bellatrex, two explainability toolboxes, and lead to both global (population-wide) as well as local (patient visit-specific) insights. RESULTS: On the task of predicting progression in 2 years, the random survival forest achieves state-of-the-art performance, comparable to previous work employing a random forest. However, here the random survival forest has the added advantage of being able to predict progression over a longer time horizon, with AUROC >60% for the first 10 years after baseline. Explainability techniques further validated the model by extracting clinically valid insights from the predictions made by the model. For example, a clear decline in the per-visit probability of progression is observed in more recent years since 2012, likely reflecting globally increasing use of more effective MS therapies. CONCLUSION: The binary classification models found in the literature can be extended to a time-to-event setting without loss of performance, thus allowing a more comprehensive prediction of patient prognosis. Furthermore, explainability techniques proved to be key to reach a better understanding of the model and increase validation of its behaviour.

• MeSH
• algoritmy MeSH
• časové faktory MeSH
• dospělí MeSH
• lidé MeSH
• prognóza MeSH
• progrese nemoci * MeSH
• registrace MeSH
• ROC křivka MeSH
• roztroušená skleróza * patofyziologie   MeSH
• strojové učení * MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

BACKGROUND: Disability progression is a key milestone in the disease evolution of people with multiple sclerosis (PwMS). Prediction models of the probability of disability progression have not yet reached the level of trust needed to be adopted in the clinic. A common benchmark to assess model development in multiple sclerosis is also currently lacking. METHODS: Data of adult PwMS with a follow-up of at least three years from 146 MS centers, spread over 40 countries and collected by the MSBase consortium was used. With basic inclusion criteria for quality requirements, it represents a total of 15, 240 PwMS. External validation was performed and repeated five times to assess the significance of the results. Transparent Reporting for Individual Prognosis Or Diagnosis (TRIPOD) guidelines were followed. Confirmed disability progression after two years was predicted, with a confirmation window of six months. Only routinely collected variables were used such as the expanded disability status scale, treatment, relapse information, and MS course. To learn the probability of disability progression, state-of-the-art machine learning models were investigated. The discrimination performance of the models is evaluated with the area under the receiver operator curve (ROC-AUC) and under the precision recall curve (AUC-PR), and their calibration via the Brier score and the expected calibration error. All our preprocessing and model code are available at https://gitlab.com/edebrouwer/ms_benchmark, making this task an ideal benchmark for predicting disability progression in MS. FINDINGS: Machine learning models achieved a ROC-AUC of 0⋅71 ± 0⋅01, an AUC-PR of 0⋅26 ± 0⋅02, a Brier score of 0⋅1 ± 0⋅01 and an expected calibration error of 0⋅07 ± 0⋅04. The history of disability progression was identified as being more predictive for future disability progression than the treatment or relapses history. CONCLUSIONS: Good discrimination and calibration performance on an external validation set is achieved, using only routinely collected variables. This suggests machine-learning models can reliably inform clinicians about the future occurrence of progression and are mature for a clinical impact study.

• Publikační typ
• časopisecké články MeSH

BACKGROUND: Simultaneous comparisons of multiple disease-modifying therapies for relapsing-remitting multiple sclerosis (RRMS) over an extended follow-up are lacking. Here we emulate a randomised trial simultaneously comparing the effectiveness of six commonly used therapies over 5 years. METHODS: Data from 74 centres in 35 countries were sourced from MSBase. For each patient, the first eligible intervention was analysed, censoring at change/discontinuation of treatment. The compared interventions included natalizumab, fingolimod, dimethyl fumarate, teriflunomide, interferon beta, glatiramer acetate and no treatment. Marginal structural Cox models (MSMs) were used to estimate the average treatment effects (ATEs) and the average treatment effects among the treated (ATT), rebalancing the compared groups at 6-monthly intervals on age, sex, birth-year, pregnancy status, treatment, relapses, disease duration, disability and disease course. The outcomes analysed were incidence of relapses, 12-month confirmed disability worsening and improvement. RESULTS: 23 236 eligible patients were diagnosed with RRMS or clinically isolated syndrome. Compared with glatiramer acetate (reference), several therapies showed a superior ATE in reducing relapses: natalizumab (HR=0.44, 95% CI=0.40 to 0.50), fingolimod (HR=0.60, 95% CI=0.54 to 0.66) and dimethyl fumarate (HR=0.78, 95% CI=0.66 to 0.92). Further, natalizumab (HR=0.43, 95% CI=0.32 to 0.56) showed a superior ATE in reducing disability worsening and in disability improvement (HR=1.32, 95% CI=1.08 to 1.60). The pairwise ATT comparisons also showed superior effects of natalizumab followed by fingolimod on relapses and disability. CONCLUSIONS: The effectiveness of natalizumab and fingolimod in active RRMS is superior to dimethyl fumarate, teriflunomide, glatiramer acetate and interferon beta. This study demonstrates the utility of MSM in emulating trials to compare clinical effectiveness among multiple interventions simultaneously.

• MeSH
• dimethyl fumarát terapeutické užití   MeSH
• fingolimod hydrochlorid terapeutické užití   MeSH
• glatiramer acetát terapeutické užití   MeSH
• imunosupresiva terapeutické užití   MeSH
• interferon beta terapeutické užití   MeSH
• lidé MeSH
• natalizumab terapeutické užití   MeSH
• recidiva MeSH
• relabující-remitující roztroušená skleróza * farmakoterapie   MeSH
• roztroušená skleróza * farmakoterapie   MeSH
• těhotenství MeSH
• Check Tag
• lidé MeSH
• těhotenství MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• randomizované kontrolované studie MeSH

BACKGROUND: The prognostic significance of non-disabling relapses in people with relapsing-remitting multiple sclerosis (RRMS) is unclear. OBJECTIVE: To determine whether early non-disabling relapses predict disability accumulation in RRMS. METHODS: We redefined mild relapses in MSBase as 'non-disabling', and moderate or severe relapses as 'disabling'. We used mixed-effects Cox models to compare 90-day confirmed disability accumulation events in people with exclusively non-disabling relapses within 2 years of RRMS diagnosis to those with no early relapses; and any early disabling relapses. Analyses were stratified by disease-modifying therapy (DMT) efficacy during follow-up. RESULTS: People who experienced non-disabling relapses within 2 years of RRMS diagnosis accumulated more disability than those with no early relapses if they were untreated (n = 285 vs 4717; hazard ratio (HR) = 1.29, 95% confidence interval (CI) = 1.00-1.68) or given platform DMTs (n = 1074 vs 7262; HR = 1.33, 95% CI = 1.15-1.54), but not if given high-efficacy DMTs (n = 572 vs 3534; HR = 0.90, 95% CI = 0.71-1.13) during follow-up. Differences in disability accumulation between those with early non-disabling relapses and those with early disabling relapses were not confirmed statistically. CONCLUSION: This study suggests that early non-disabling relapses are associated with a higher risk of disability accumulation than no early relapses in RRMS. This risk may be mitigated by high-efficacy DMTs. Therefore, non-disabling relapses should be considered when making treatment decisions.

• MeSH
• lidé MeSH
• prognóza MeSH
• recidiva MeSH
• relabující-remitující roztroušená skleróza * farmakoterapie   MeSH
• roztroušená skleróza * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

BACKGROUND: In the absence of evidence from randomised controlled trials, observational data can be used to emulate clinical trials and guide clinical decisions. Observational studies are, however, susceptible to confounding and bias. Among the used techniques to reduce indication bias are propensity score matching and marginal structural models. OBJECTIVE: To use the comparative effectiveness of fingolimod vs natalizumab to compare the results obtained with propensity score matching and marginal structural models. METHODS: Patients with clinically isolated syndrome or relapsing remitting MS who were treated with either fingolimod or natalizumab were identified in the MSBase registry. Patients were propensity score matched, and inverse probability of treatment weighted at six monthly intervals, using the following variables: age, sex, disability, MS duration, MS course, prior relapses, and prior therapies. Studied outcomes were cumulative hazard of relapse, disability accumulation, and disability improvement. RESULTS: 4608 patients (1659 natalizumab, 2949 fingolimod) fulfilled inclusion criteria, and were propensity score matched or repeatedly reweighed with marginal structural models. Natalizumab treatment was associated with a lower probability of relapse (PS matching: HR 0.67 [95% CI 0.62-0.80]; marginal structural model: 0.71 [0.62-0.80]), and higher probability of disability improvement (PS matching: 1.21 [1.02 -1.43]; marginal structural model 1.43 1.19 -1.72]). There was no evidence of a difference in the magnitude of effect between the two methods. CONCLUSIONS: The relative effectiveness of two therapies can be efficiently compared by either marginal structural models or propensity score matching when applied in clearly defined clinical contexts and in sufficiently powered cohorts.

• MeSH
• fingolimod hydrochlorid terapeutické užití   MeSH
• imunologické faktory terapeutické užití   MeSH
• imunosupresiva terapeutické užití   MeSH
• lidé MeSH
• natalizumab terapeutické užití   MeSH
• recidiva MeSH
• relabující-remitující roztroušená skleróza * farmakoterapie   MeSH
• roztroušená skleróza * farmakoterapie   MeSH
• tendenční skóre MeSH
• výsledek terapie MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

BACKGROUND AND PURPOSE: This study assessed the effect of patient characteristics on the response to disease-modifying therapy (DMT) in multiple sclerosis (MS). METHODS: We extracted data from 61,810 patients from 135 centers across 35 countries from the MSBase registry. The selection criteria were: clinically isolated syndrome or definite MS, follow-up ≥ 1 year, and Expanded Disability Status Scale (EDSS) score ≥ 3, with ≥1 score recorded per year. Marginal structural models with interaction terms were used to compare the hazards of 12-month confirmed worsening and improvement of disability, and the incidence of relapses between treated and untreated patients stratified by their characteristics. RESULTS: Among 24,344 patients with relapsing MS, those on DMTs experienced 48% reduction in relapse incidence (hazard ratio [HR] = 0.52, 95% confidence interval [CI] = 0.45-0.60), 46% lower risk of disability worsening (HR = 0.54, 95% CI = 0.41-0.71), and 32% greater chance of disability improvement (HR = 1.32, 95% CI = 1.09-1.59). The effect of DMTs on EDSS worsening and improvement and the risk of relapses was attenuated with more severe disability. The magnitude of the effect of DMT on suppressing relapses declined with higher prior relapse rate and prior cerebral magnetic resonance imaging activity. We did not find any evidence for the effect of age on the effectiveness of DMT. After inclusion of 1985 participants with progressive MS, the effect of DMT on disability mostly depended on MS phenotype, whereas its effect on relapses was driven mainly by prior relapse activity. CONCLUSIONS: DMT is generally most effective among patients with lower disability and in relapsing MS phenotypes. There is no evidence of attenuation of the effect of DMT with age.

• MeSH
• chronicko-progresivní roztroušená skleróza * MeSH
• imunoterapie MeSH
• lidé MeSH
• proporcionální rizikové modely MeSH
• recidiva MeSH
• relabující-remitující roztroušená skleróza * MeSH
• roztroušená skleróza * terapie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Geographical variations in the incidence and prevalence of multiple sclerosis have been reported globally. Latitude as a surrogate for exposure to ultraviolet radiation but also other lifestyle and environmental factors are regarded as drivers of this variation. No previous studies evaluated geographical variation in the risk of secondary progressive multiple sclerosis, an advanced form of multiple sclerosis that is characterized by steady accrual of irreversible disability. We evaluated differences in the risk of secondary progressive multiple sclerosis in relation to latitude and country of residence, modified by high-to-moderate efficacy immunotherapy in a geographically diverse cohort of patients with relapsing-remitting multiple sclerosis. The study included relapsing-remitting multiple sclerosis patients from the global MSBase registry with at least one recorded assessment of disability. Secondary progressive multiple sclerosis was identified as per clinician diagnosis. Sensitivity analyses used the operationalized definition of secondary progressive multiple sclerosis and the Swedish decision tree algorithm. A proportional hazards model was used to estimate the cumulative risk of secondary progressive multiple sclerosis by country of residence (latitude), adjusted for sex, age at disease onset, time from onset to relapsing-remitting phase, disability (Multiple Sclerosis Severity Score) and relapse activity at study inclusion, national multiple sclerosis prevalence, government health expenditure, and proportion of time treated with high-to-moderate efficacy disease-modifying therapy. Geographical variation in time from relapsing-remitting phase to secondary progressive phase of multiple sclerosis was modelled through a proportional hazards model with spatially correlated frailties. We included 51 126 patients (72% female) from 27 countries. The median survival time from relapsing-remitting phase to secondary progressive multiple sclerosis among all patients was 39 (95% confidence interval: 37 to 43) years. Higher latitude [median hazard ratio = 1.21, 95% credible interval (1.16, 1.26)], higher national multiple sclerosis prevalence [1.07 (1.03, 1.11)], male sex [1.30 (1.22, 1.39)], older age at onset [1.35 (1.30, 1.39)], higher disability [2.40 (2.34, 2.47)] and frequent relapses [1.18 (1.15, 1.21)] at inclusion were associated with increased hazard of secondary progressive multiple sclerosis. Higher proportion of time on high-to-moderate efficacy therapy substantially reduced the hazard of secondary progressive multiple sclerosis [0.76 (0.73, 0.79)] and reduced the effect of latitude [interaction: 0.95 (0.92, 0.99)]. At the country-level, patients in Oman, Tunisia, Iran and Canada had higher risks of secondary progressive multiple sclerosis relative to the other studied regions. Higher latitude of residence is associated with a higher probability of developing secondary progressive multiple sclerosis. High-to-moderate efficacy immunotherapy can mitigate some of this geographically co-determined risk.

• MeSH
• chronicko-progresivní roztroušená skleróza * epidemiologie   MeSH
• lidé MeSH
• lokální recidiva nádoru MeSH
• progrese nemoci MeSH
• relabující-remitující roztroušená skleróza * epidemiologie   MeSH
• roztroušená skleróza * epidemiologie   diagnóza   MeSH
• ultrafialové záření MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

BACKGROUND AND PURPOSE: The prevention of disability over the long term is the main treatment goal in multiple sclerosis (MS); however, randomized clinical trials evaluate only short-term treatment effects on disability. This study aimed to define criteria for 6-month confirmed disability progression events of MS with a high probability of resulting in sustained long-term disability worsening. METHODS: In total, 14,802 6-month confirmed disability progression events were identified in 8741 patients from the global MSBase registry. For each 6-month confirmed progression event (13,321 in the development and 1481 in the validation cohort), a sustained progression score was calculated based on the demographic and clinical characteristics at the time of progression that were predictive of long-term disability worsening. The score was externally validated in the Cladribine Tablets Treating Multiple Sclerosis Orally (CLARITY) trial. RESULTS: The score was based on age, sex, MS phenotype, relapse activity, disability score and its change from baseline, number of affected functional system domains and worsening in six of the domains. In the internal validation cohort, a 61% lower chance of improvement was estimated with each unit increase in the score (hazard ratio 0.39, 95% confidence interval 0.29-0.52; discriminatory index 0.89). The proportions of progression events sustained at 5 years stratified by the score were 1: 72%; 2: 88%; 3: 94%; 4: 100%. The results of the CLARITY trial were confirmed for reduction of disability progression that was >88% likely to be sustained (events with score ˃1.5). CONCLUSIONS: Clinicodemographic characteristics of 6-month confirmed disability progression events identify those at high risk of sustained long-term disability. This knowledge will allow future trials to better assess the effect of therapy on long-term disability accrual.

• MeSH
• kladribin terapeutické užití   MeSH
• kohortové studie MeSH
• lidé MeSH
• posuzování pracovní neschopnosti * MeSH
• progrese nemoci MeSH
• randomizované kontrolované studie jako téma MeSH
• relabující-remitující roztroušená skleróza MeSH
• roztroušená skleróza * farmakoterapie   patologie   MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

BACKGROUND AND PURPOSE: Reaching Expanded Disability Status Scale (EDSS) ≥7.0 represents the requirement for a wheelchair. Here we (i) assess the effect of ocrelizumab on time to EDSS ≥7.0 over the ORATORIO (NCT01194570) double-blind and extended controlled periods (DBP+ECP), (ii) quantify likely long-term benefits by extrapolating results, and (iii) assess the plausibility of extrapolations using an independent real-world cohort (MSBase registry; ACTRN12605000455662). METHODS: Post hoc analyses assessing time to 24-week confirmed EDSS ≥7.0 in two cohorts of patients with primary progressive multiple sclerosis (baseline EDSS 3.0-6.5) were investigated in ORATORIO and MSBase. RESULTS: In the ORATORIO DBP+ECP, ocrelizumab reduced the risk of 24-week confirmed EDSS ≥7.0 (hazard ratio = 0.54, 95% confidence interval [CI]: 0.31-0.92; p = 0.022). Extrapolated median time to 24-week confirmed EDSS ≥7.0 was 12.1 and 19.2 years for placebo and ocrelizumab, respectively (7.1-year delay [95% CI: -4.3 to 18.4]). In MSBase, the median time to 24-week confirmed EDSS ≥7.0 was 12.4 years. CONCLUSIONS: Compared with placebo, ocrelizumab significantly delayed time to 24-week confirmed wheelchair requirement in ORATORIO. The plausibility of the extrapolated median time to reach this milestone in the placebo group was supported by observed real-world data from MSBase. Extrapolated benefits for ocrelizumab over placebo could represent a truly meaningful delay in loss of ambulation and independence.

• MeSH
• chronicko-progresivní roztroušená skleróza * farmakoterapie   MeSH
• lidé MeSH
• progrese nemoci MeSH
• registrace MeSH
• roztroušená skleróza * farmakoterapie   MeSH
• vozíky pro invalidy * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• randomizované kontrolované studie MeSH