The natural history of multiple sclerosis: a geographically based study. 5. The clinical features and natural history of primary progressive multiple sclerosis

Towards a Unified Set of Diagnostic Criteria for Multiple Sclerosis

OBJECTIVE

The 2017 McDonald criteria continued the separation of diagnostic criteria for relapsing-remitting multiple sclerosis (RRMS) and primary progressive MS (PPMS) for historical, rather than biological, reasons. We aimed to explore the feasibility of a single, unified set of diagnostic criteria when applied to patients with suspected PPMS.

METHODS

We retrospectively identified patients evaluated for suspected PPMS at 5 European centers. The 2017 McDonald PPMS criteria was the gold standard against which the 2017 McDonald RRMS dissemination in space (DIS) and dissemination in time criteria were evaluated. We also investigated modified RRMS DIS criteria, including: (i) optic nerve lesions; (ii) ≥2 spinal cord lesions; and (iii) higher fulfilment of DIS criteria alone (lesions in ≥3 regions) without dissemination in time/positive cerebrospinal fluid, for a diagnosis of PPMS.

RESULTS

A total of 282 patients were diagnosed with PPMS using the 2017 McDonald criteria, and 40 with alternate disorders. The 2017 McDonald RRMS DIS criteria and the modified DIS criteria including the optic nerve or ≥2 spinal cord lesions performed well in PPMS diagnosis when combined with dissemination in time/positive cerebrospinal fluid (sensitivity 92.9-95.4%, specificity 95%, accuracy 93.2-95.3%). A diagnosis of PPMS based on high fulfillment of modified RRMS DIS criteria had high specificity, but low sensitivity. A diagnostic algorithm applicable to patients evaluated for suspected MS is proposed.

INTERPRETATION

The 2017 McDonald RRMS criteria and modifications to DIS criteria, currently under consideration, performed well in PPMS diagnosis. Forthcoming revisions to the McDonald criteria should consider a single, unified set of diagnostic criteria for MS. ANN NEUROL 2025;97:571-582.

Untackling the economics of multiple sclerosis: A systematic review of economic evaluations of disease-modifying therapies indicated for multiple sclerosis

OBJECTIVES

Multiple sclerosis (MS) comprises a chronic, neurodegenerative, and inflammatory illness of the central nervous system that affects 2.8 million people worldwide. MS is only treatable, and to this direction, the disease armamentarium has been significantly enriched with new agents, albeit with burgeoning costs and engulfed by uncertainty. The scope of this review is to assess the efficiency of MS agents.

METHODS

We performed a systematic literature review, spanning from 2000 to 2023 on adult patients with any form of MS, receiving any MS indicated modality and whose outcome was ICUR and ICER. The methodological quality of the studies was assessed with the Quality of Health Economics Studies tool.

RESULTS

We identified 57 studies that met the inclusion criteria. Studies were hailing from 20 countries and a multitude of methodological approaches were documented across several types of MS. A substantial level of divergence regarding results was noted. Country setting, study perspective (societal vs payer) the selection of the benchmark treatment, data extrapolation beyond the reported timeframe of the trial and time horizon of the model exerted a substantial impact on the results. Dimethyl fumarate was consistently interrelated with a positive cost-effectiveness ratio. The same applies for fampridine, while Cladribine was proved to be a dominating agent. Ocrelizumab also evinced efficiency. The same applies for the early data of Siponimod and ofatumumab, however the breadth of their studies lags compares to other agents, and these results have to be further corroborated. On the contrary Interferons demonstrated a non-efficient profile and their use as a comparative benchmark arm brought about several complications regarding the incremental financial aspect of economic evaluations, since they are commonly used as such. The results of fingolimod and natalizumab studies are embroiled in uncertainty. Moreover, the efficiency factor was positively correlated by earlier access of patients to these products, rather than delayed one. Result discrepancies among the same country were also imputed to the adopted utility and disutility values and the methodological approach for data extrapolation. Results were sensitive to an array of factors. Among them, the effectiveness of the products, coupled with the cost of the agents emerged as the most important drivers. Uncertainty was further compounded by several other parameters such as discounting, efficacy waning, horizon of the study, disability base rate and utility of the patients. We also outlined that the efficiency of product is pertinent to the disease type. Results such as dominance must be interpreted with caution since in certain cases a dominating agent was proved to be as such by capitalizing on marginal incremental health gains, compared to the standard comparative treatment.

CONCLUSIONS

An increasing body of evidence consisting of economic evaluations for MS was retrieved. These studies exhibited high quality, however, the consistency regarding results was impaired.

Primary Progressive Multiple Sclerosis-A Key to Understanding and Managing Disease Progression

Primary progressive multiple sclerosis (PPMS), the least frequent type of multiple sclerosis (MS), is characterized by a specific course and clinical symptoms, and it is associated with a poor prognosis. It requires extensive differential diagnosis and often a long-term follow-up before its correct recognition. Despite recent progress in research into and treatment for progressive MS, the diagnosis and management of this type of disease still poses a challenge. Considering the modern concept of progression "smoldering" throughout all the stages of disease, a thorough exploration of PPMS may provide a better insight into mechanisms of progression in MS, with potential clinical implications. The goal of this study was to review the current evidence from investigations of PPMS, including its background, clinical characteristics, potential biomarkers and therapeutic opportunities. Processes underlying CNS damage in PPMS are discussed, including chronic immune-mediated inflammation, neurodegeneration, and remyelination failure. A review of potential clinical, biochemical and radiological biomarkers is presented, which is useful in monitoring and predicting the progression of PPMS. Therapeutic options for PPMS are summarized, with approved therapies, ongoing clinical trials and future directions of investigations. The clinical implications of findings from PPMS research would be associated with reliable assessments of disease outcomes, improvements in individualized therapeutic approaches and, hopefully, novel therapeutic targets, relevant for the management of progression.

Prevalence and disease disability in immigrants with multiple sclerosis in Malmö, southern Sweden

BACKGROUND

Multiple sclerosis (MS) is the most common chronic demyelinating disease of the central nervous system and the major non-traumatic cause of permanent disability in young adults. Several migration studies have been performed over the years suggesting a pattern of higher disease disability in certain ethnic groups. To our knowledge, differences in disease progression in immigrants have not been studied in Sweden before. Thus, the aims of our study were to estimate the prevalence of multiple sclerosis among first-generation immigrants in the City of Malmö and to compare differences in disease severity with the native population.

METHODS

All persons with multiple sclerosis living in Malmö on prevalence day 31 Dec 2010 were included. Cases were classified according to the country of birth into Scandinavians, Western and non-Western.

RESULTS

The crude prevalence was 100/100,000 (95% CI, 80-124) among first-generation immigrants, 154/100,000 (95% CI, 137-173) among individuals with Scandinavian background, 123/100,000 (95% CI, 94-162) in the Western group and 76/100,000 (95% CI, 53-108) in the non-Western group. The mean Multiple Sclerosis Severity Score (MSSS) value among Scandinavians was 4.2 (SD 3.5), whereas the figures in the immigrant group were 4.6 (SD 3.3) and 5.2 (SD 3.7) among Westerns respectively non-Westerns, which differences were not statistically significant. When adjusting for gender, age at onset and initial disease course, the mean MSSS difference between the non-Western and the Scandinavian individuals was 1.7 (95% CI 0.18-3.3, p = 0.030). There were no differences on time to diagnosis or the time from diagnosis to treatment initiation between the three groups.

CONCLUSIONS

We found a lower prevalence among Western and non-Western first-generation immigrants compared to the Scandinavian population and a more severe disease in non-Western immigrants than in Scandinavians.

Microglia and Multiple Sclerosis

Multiple sclerosis (MS) is a devastating autoimmune disease that leads to profound disability. This disability arises from the stochastic, regional loss of myelin-the insulating sheath surrounding neurons-in the central nervous system (CNS). The demyelinated regions are dominated by the brain's resident macrophages: microglia. Microglia perform a variety of functions in MS and are thought to initiate and perpetuate demyelination through their interactions with peripheral immune cells that traffic into the brain. However, microglia are also likely essential for recruiting and promoting the differentiation of cells that can restore lost myelin in a process known as remyelination. Given these seemingly opposing functions, an overarching beneficial or detrimental role is yet to be ascribed to these immune cells. In this chapter, we will discuss microglia dynamics throughout the MS disease course and probe the apparent dichotomy of microglia as the drivers of both demyelination and remyelination.

Real-world challenges in the diagnosis of primary progressive multiple sclerosis

BACKGROUND AND PURPOSE

Despite the 2017 revisions to the McDonald criteria, diagnosing primary progressive multiple sclerosis (PPMS) remains challenging. To improve clinical practice, the aim was to identify frequent diagnostic challenges in a real-world setting and associate these with the performance of the 2010 and 2017 PPMS diagnostic McDonald criteria.

METHODS

Clinical, radiological and laboratory characteristics at the time of diagnosis were retrospectively recorded from designated PPMS patient files. Possible complicating factors were recorded such as confounding comorbidity, signs indicative of alternative diagnoses, possible earlier relapses and/or incomplete diagnostic work-up (no cerebrospinal fluid examination and/or magnetic resonance imaging brain and spinal cord). The percentages of patients fulfilling the 2010 and 2017 McDonald criteria were calculated after censoring patients with these complicating factors.

RESULTS

A total of 322 designated PPMS patients were included. Of all participants, it was found that n = 28/322 had confounding comorbidity and/or signs indicative of alternative diagnoses, n = 103/294 had possible initial relapsing and/or uncertainly progressive phenotypes and n = 73/191 received an incomplete diagnostic work-up. When applying the 2010 and 2017 diagnostic PPMS McDonald criteria on n = 118 cases with a full diagnostic work-up and a primary progressive disease course without a better alternative explanation, these were met by 104/118 (88.1%) and 98/118 remaining patients (83.1%), respectively (p = 0.15).

CONCLUSION

Accurate interpretation of the initial clinical course, consideration of alternative diagnoses and a full diagnostic work-up are the cornerstones of a PPMS diagnosis. When these conditions are met, the 2010 and 2017 McDonald criteria for PPMS perform similarly, emphasizing the importance of their appropriate application in clinical practice.

The Association of Health Locus of Control with Clinical and Psychosocial Aspects of Living with Multiple Sclerosis

Health Locus of control (LOC) refers to one's beliefs regarding control over one's health. This study aimed to determine the relationship between LOC on clinical and psychosocial aspects associated with multiple sclerosis (MS). 5059 participants with MS completed a questionnaire pack including the Multidimensional Health Locus of Control Scale. Associations between LOC and sociodemographic (age, gender, educational level) and clinical variables (duration, disability, depression, anxiety, self-efficacy, QoL) were explored. LOC was found to be significantly associated with all of the clinical variables and age, but not gender or educational level. When controlling for level of disability, Chance (CLOC) was associated with higher self-efficacy, lower anxiety and higher QoL than Powerful Others (PLOC), while Internal (ILOC) had no association. The proportion with ILOC preference was lower in increased disability. In MS, believing that health is controlled mainly by chance confers the most benefit with regard to quality of life. There is prima-facie evidence that LOC preference changes with MS progression, in a pattern that is protective against psychological distress.

Patient-reported outcomes in multiple sclerosis: a prospective registry cohort study

Registries have the potential to tackle some of the current limitations in determining the long-term impact of multiple sclerosis. Online assessments using patient-reported outcomes can streamline follow-up enabling large-scale, long-term, cost-effective, home-based, and patient-focused data collection. However, registry data are sparsely sampled and the sensitivity of patient-reported outcomes relative to clinician-reported scales is unknown, making it hard to fully leverage their unique scope and scale to derive insights. This retrospective and prospective cohort study over 11 years involved 15 976 patients with multiple sclerosis from the United Kingdom Multiples Sclerosis Register. Primary outcomes were changes in two patient-reported outcomes: Multiple Sclerosis Impact Scale motor component, and Multiple Sclerosis Walking Scale. First, we investigated their validity in measuring the impact of physical disability in multiple sclerosis, by looking at their sensitivity to disease subtype and duration. We grouped the available records (91 351 for Multiple Sclerosis Impact Scale motor and 68 092 for Multiple Sclerosis Walking Scale) by these two factors, and statistically compared the resulting groups using a novel approach based on Monte Carlo permutation analysis that was designed to cope with the intrinsic sparsity of registry data. Next, we used the patient-reported outcomes to draw novel insights into the developmental time course of subtypes; in particular, the period preceding the transition from relapsing to progressive forms. We report a robust main effect of disease subtype on the patient-reported outcomes and interactions of disease subtype with duration (all P < 0.0001). Specifically, patient-reported outcomes worsen with disease duration for all subtypes (all P < 0.0001) apart from benign multiple sclerosis (Multiple Sclerosis Impact Scale motor: P = 0.796; Multiple Sclerosis Walking Scale: P = 0.983). Furthermore, the patient-reported outcomes of each subtype are statistically different from those of the other subtypes at all time bins (Multiple Sclerosis Impact Scale motor: all P < 0.05; Multiple Sclerosis Walking Scale: all P < 0.01) except when comparing relapsing-remitting multiple sclerosis with benign multiple sclerosis and primary progressive multiple sclerosis with secondary progressive multiple sclerosis. Notably, there were statistically significant differences between relapsing-remitting and progressive subtypes at disease onset. Critically, the patient-reported outcomes are sensitive to future transitions to progressive subtypes, with individuals who transition presenting with higher patient-reported outcomes in their relapsing-remitting phase compared to individuals who don't transition since onset (all P < 0.0001). Patient-reported outcomes capture different patterns of physical worsening over disease length and across subtypes; therefore, they are a valid tool to measure the physical impact of multiple sclerosis over the long-term and cost-effectively. Furthermore, more advanced physical disability manifests years before clinical detection of progressive subtypes, adding evidence to the presence of a multiple sclerosis prodrome.

The natural history of primary progressive multiple sclerosis: insights from the German NeuroTransData registry

BACKGROUND

Primary progressive multiple sclerosis (PPMS) is characterised by gradual worsening of disability from symptom onset. Knowledge about the natural course of PPMS remains limited.

METHODS

PPMS patients from the German NeuroTransData (NTD) MS registry with data from 56 outpatient practices were employed for retrospective cross-sectional and longitudinal analyses. The cross-sectional analysis included a contemporary PPMS cohort with a documented visit within the last 2 years before index date (1 Jan 2021). The longitudinal analysis included a disease modifying therapy (DMT)-naïve population and focused on the evolution of expanded disability status scale (EDSS) from the first available assessment at or after diagnosis within the NTD registry to index date. Outcome measures were estimated median time from first EDSS assessment to first 24-week confirmed EDSS ≥ 4 and ≥ 7. Besides EDSS change, the proportion of patients on disability pension were described over time.

RESULTS

The cross-sectional analysis included 481 PPMS patients (59.9% female, mean [standard deviation, SD] age 60.5 [11.5] years, mean [SD] EDSS 4.9 [2.1]). Estimated median time from first EDSS assessment after diagnosis to reach 24-week confirmed EDSS ≥ 4 for DMT-naïve patients was 6.9 years. Median time to EDSS ≥ 7 was 9.7 years for 25% of the population. Over a decade mean (SD) EDSS scores increased from 4.6 (2.1) to 5.7 (2.0); the proportion of patients on disability pension increased from 18.9% to 33.3%.

CONCLUSIONS

This study provides first insights into the German NTD real-world cohort of PPMS patients. Findings confirm the steadily deteriorating course of PPMS accompanied by increasingly limited quality of life.

Clinical validation of a multi-protein, serum-based assay for disease activity assessments in multiple sclerosis

An 18-protein multiple sclerosis (MS) disease activity (DA) test was validated based on associations between algorithm scores and clinical/radiographic assessments (N = 614 serum samples; Train [n = 426; algorithm development] and Test [n = 188; evaluation] subsets). The multi-protein model was trained based on presence/absence of gadolinium-positive (Gd+) lesions and was also strongly associated with new/enlarging T2 lesions, and active versus stable disease (composite of radiographic and clinical evidence of DA) with improved performance (p < 0.05) compared to the neurofilament light single protein model. The odds of having ≥1 Gd + lesions with a moderate/high DA score were 4.49 times that of a low DA score, and the odds of having ≥2 Gd + lesions with a high DA score were 20.99 times that of a low/moderate DA score. The MSDA Test was clinically validated with improved performance compared to the top-performing single-protein model and can serve as a quantitative tool to enhance the care of MS patients.

Longitudinal Effects of Sex, Aging, and Multiple Sclerosis Diagnosis on Function

BACKGROUND

A gap in research about the trajectories of function among men and women aging with functional limitations because of multiple sclerosis (MS) hinders ability to plan for future needs.

OBJECTIVES

Using a biopsychosocial model, we characterize how men and women with MS report changes over time in their function and test how person-level differences in age, diagnosis duration, and sex influence perceived function.

METHODS

A longitudinal study with multiple waves of surveys was used to collect data on participant perceptions of function, as well as demographic and contextual variables. Self-reported functional limitation was measured over a decade. The study participants were community residing with physician-diagnosed MS.

RESULTS

The people with MS had a diagnosis duration of about 13 years and were around 51 years of age, on average, at the start of the study. They were primarily women and non-Hispanic White. We analyzed the data using mixed-effects models. Subject-specific, functional limitation trajectories were described best with a quadratic growth model. Relative to men, women reported lower functional limitation and greater between-person variation and rates of acceleration in functional limitation scores.

DISCUSSION

Results suggest function progressed through two pathways for over a decade, particularly closer to diagnoses. Variability in trajectories between individuals based on sex and years since diagnosis of disease indicates that men and women with MS may experience perceptions of their function with age differently. This has implications for clinician advice to men and women with MS.

Age and sex differences on anti-hyperglycemic medication exposure and risk of newly diagnosed multiple sclerosis in propensity score matched type 2 diabetics

Background

The association between exposure to anti-hyperglycemic medications (A-HgM) for Type 2 Diabetes Mellitus (T2D) treatment and Multiple Sclerosis (MS) in T2D patients is unclear.

Methods

This retrospective cohort analysis used the Mariner claims database. Patient records were surveyed for a diagnosis of MS starting 12 months after diagnosis of T2D. Patients were required to be actively enrolled in the Mariner claims records for six months prior and at least three years after the diagnosis of T2D without a history of previous neurodegenerative disease. Survival analysis was used to determine the association between A-HgM exposure and diagnosis of MS. A propensity score approach was used to minimize measured and unmeasured selection bias. The analyses were conducted between January 1st and April 28th, 2021.

Findings

In T2D patients younger than 45, A-HgM exposure was associated with a reduced risk of developing MS (RR: 0.22, 95%CI: 0.17-0.29, p-value <0.001). In contrast, A-HgM exposure in patients older than 45 was associated with an increased risk of MS with women exhibiting greater risk (RR: 1.53, 95%CI: 1.39-1.69, p < 0.001) than men (RR: 1.17, 95%CI: 1.01-1.37, p = 0 · 04). Patients who developed MS had a higher incidence of baseline comorbidities. Mean follow-up was 6.2 years with a standard deviation of 1.8 years.

Interpretation

In this study, A-HgM exposure in patients with T2D was associated with reduced risk of MS in patients younger than 45 whereas in patients older than 45, exposure to A-HgM was associated with an increased risk of newly diagnosed MS, particularly in women.

Multiple Sclerosis Progressive Courses: A Clinical Cohort Long-Term Disability Progression Study

OBJECTIVES

Improving the understanding of multiple sclerosis (MS) mechanism and disability progression over time is essential to assess the value of healthcare interventions. Poor or no data on disability progression are available for progressive courses. This study aims to fill this gap.

METHODS

An observational cohort study of patients with primary MS (PPMS) and secondary progressive MS (SPMS) was conducted on 2 Italian MS centers disease registries over an observational time of 34 years. Annual transition probabilities among Expanded Disability Status Scale (EDSS) states were estimated using continuous Markov models. A sensitivity analysis was performed in relation to clinical characteristic associated to disability progression.

RESULTS

The study cohort included 758 patients (274 PPMS and 434 SPMS) with a median follow-up of 8.2 years. Annual transition probability matrices of SPMS and PPMS reported different annual probabilities to move within EDSS levels. Excluding EDSS associated to relapse events or patient with relapses, the annual probability of staying stable in an EDSS level increased in both disease courses even not significantly.

CONCLUSIONS

This study provides estimates of annual disability progression as EDSS changes for PPMS and SPMS. These estimates could be a useful tool for healthcare decision makers and clinicians to properly assess impact of clinical interventions.

Dietary Patterns and Metabolic Disorders in Polish Adults with Multiple Sclerosis

Diet plays a major role in the aetiopathogenesis of many neurological diseases and may exacerbate their symptoms by inducing the occurrence of metabolic disorders. The results of research on the role of diet in the course of multiple sclerosis (MS) are ambiguous, and there is still no consensus concerning dietary recommendations for patients with MS. The aim of this study was to analyse the dietary patterns (DPs) of patients with MS and to assess the relationships between these DPs and the metabolic disorders. The study participants were comprised of 330 patients aged 41.9 ± 10.8 years. A survey questionnaire was used to collect data related to diet, lifestyle and health. The DPs were identified using a principal component analysis (PCA). Three DPs were identified: Traditional Polish, Prudent and Fast Food & Convenience Food. An analysis of the odds ratios adjusted for age, gender, smoking and education showed that a patient’s adherence to the Traditional Polish and the Fast Food & Convenience Food DPs increased the likelihood of abdominal obesity and low HDL-cholesterol concentration. Conversely, adherence to the Prudent DP was not significantly associated with any metabolic disorder. The results of this study confirmed that an unhealthy diet in patients with MS is connected with the presence of some metabolic risk factors. There is also an urgent need to educate patients with MS on healthy eating, because the appropriate modifications to their diet may improve their metabolic profile and clinical outcomes.

Do Hungarian multiple sclerosis care units fulfil international criteria?

A patients

Because of the past 3 decades’ extensive research, several disease modifying therapies became available, thus a paradigm change is multiple sclerosis care was necessary. In 2018 a therapeutic guideline was created recommending that treatment of persons with multiple sclerosis should take place in specified care units where the entire spectrum of disease modifying therapies is available, patient monitoring is ensured, and therapy side effects are detected and treated promptly. In 2019 multiple sclerosis care unit criteria were developed, emphasizing personnel and instrumental requirements to provide most professional care. However, no survey was conducted assessing the real-world adaptation of these criteria.

Objective

To assess whether Hungarian care units fulfil international criteria.

Methods

A self-report questionnaire was assembled based on international guidelines and sent to Hungarian care units focusing on 3 main aspects: personnel and instrumental background, disease-modifying therapy use, number of people living with multiple sclerosis receiving care in care units. Data on number of persons with multiple sclerosis were compared to Hungarian prevalence estimates. Descriptive statistics were used to analyse data.

Results

Out of 27 respondent care units, 3 fulfilled minimum requirements and 7 fulfilled minimum and recommended requirements. The least prevalent neighbouring specialties were spasticity and pain specialist, and neuro-ophthalmologist and oto-neurologist. Only 15 centres used all available disease modifying therapies. A total number of 7213 people with multiple sclerosis received care in 27 respondent centres. Compared to prevalence estimates, 2500 persons with multiple sclerosis did not receive multiple sclerosis specific care in Hungary.

Conclusion

Less than half of Hungarian care units provided sufficient care for people living with multiple sclerosis. Care units employing fewer neighbouring specialties, might have difficulties diagnosing and providing appropriate care for persons with multiple sclerosis, especially for people with progressive disease course, contributing to the reported low number of persons living with multiple sclerosis.

The role of sex and pregnancy in multiple sclerosis: what do we know and what should we do?

INTRODUCTION

Multiple sclerosis (MS) is more prevalent in women than in men. The sex of the patient, and pregnancy, are reported to be associated with the clinical features of MS. The mechanism of this is unclear.

AREAS COVERED

This review summarizes data about sex differences in MS and the role of pregnancy. Possible mechanisms for the effects of sex and pregnancy are summarized, and practical suggestions for addressing these issues are provided.

EXPERT OPINION

There is considerable interdependence of the variables that are associated with MS. Men have a worse outcome of MS, and this could be due to the same factors that lead to greater incidence of neurodegenerative disease in men. The possible role of parity on the long-term outcome of MS is of interest. Future studies that look at the mechanisms of the effects of the sex of the patient on the outcome of MS are required. However, there are some actions that can be taken without further research. We can concentrate on public health measures that address the modifiable risk factors for MS and ensure that disease is controlled in women who intend to become pregnant and use appropriate disease modifying agents during pregnancy.

Central nervous system macrophages in progressive multiple sclerosis: relationship to neurodegeneration and therapeutics

There are over 15 disease-modifying drugs that have been approved over the last 20 years for the treatment of relapsing–remitting multiple sclerosis (MS), but there are limited treatment options available for progressive MS. The development of new drugs for the treatment of progressive MS remains challenging as the pathophysiology of progressive MS is poorly understood.

The progressive phase of MS is dominated by neurodegeneration and a heightened innate immune response with trapped immune cells behind a closed blood–brain barrier in the central nervous system. Here we review microglia and border-associated macrophages, which include perivascular, meningeal, and choroid plexus macrophages, during the progressive phase of MS. These cells are vital and are largely the basis to define lesion types in MS. We will review the evidence that reactive microglia and macrophages upregulate pro-inflammatory genes and downregulate homeostatic genes, that may promote neurodegeneration in progressive MS. We will also review the factors that regulate microglia and macrophage function during progressive MS, as well as potential toxic functions of these cells. Disease-modifying drugs that solely target microglia and macrophage in progressive MS are lacking. The recent treatment successes for progressive MS include include B-cell depletion therapies and sphingosine-1-phosphate receptor modulators. We will describe several therapies being evaluated as a potential treatment option for progressive MS, such as immunomodulatory therapies that can target myeloid cells or as a potential neuroprotective agent.

Apparent changes in the epidemiology and severity of multiple sclerosis

Multiple sclerosis (MS) is an immunological disease that causes acute inflammatory lesions and chronic inflammation in the CNS, leading to tissue damage and disability. As awareness of MS has increased and options for therapy have come into use, a large amount of epidemiological data have been collected, enabling studies of changes in incidence and disease course over time. Overall, these data seem to indicate that the incidence of MS has increased, but the course of the disease has become milder, particularly in the 25 years since the first disease-modifying therapies (DMTs) became available. A clear understanding of these trends and the reasons for them is important for understanding the factors that influence the development and progression of MS, and for clinical management with respect to prevention and treatment decisions. In this Review, we consider the evidence for changes in the epidemiology of MS, focusing on trends in the incidence of the disease over time and trends in the disease severity. In addition, we discuss the factors influencing these trends, including refinement of diagnostic criteria and improvements in health-care systems that have increased diagnosis in people with mild disease, and the introduction and improvement of DMT.

Clinical predictors of disease progression in a cohort of Tunisian progressive Multiple Sclerosis

BACKGROUND

Knowledge about progressive Multiple Sclerosis (MS) is mainly based on Caucasian studies. In our North-African context, MS exhibits particular characteristics that are mainly related to a more severe phenotype. Given the limited data available, there is an imminent need to characterize progressive MS in our latitudes.

OBJECTIVE

To describe the specificities of progressive MS and identify the inherent clinical predictors of disability accrual with a Tunisian cohort.

METHODS

A retrospective, hospital-based study was conducted in the department of neurology of Razi hospital. Patients, who had been diagnosed with MS, were divided into relapsing MS (RRMS), secondary progressive MS (SPMS) and primary progressive MS (PPMS). Epidemiological, clinical and paraclinical data were compared among the three groups.

RESULTS

Of the 504 patients, a progressive MS was described among 115 patients. This percentage of (22.8%) is divided into 13.9% SPMS and 8.9% PPMS. During the first clinical attack, motor symptoms have revealed to be predominant during PPMS (91.1%). For SPMS onset, the median time was 10 years, and was significantly delayed for patients with visual onset or full recovery from the first relapse. Patients with progressive MS exhibited a more rapid disability accumulation.

CONCLUSION

Compared to Caucasians, Tunisians exhibited a faster rate of conversion to SPMS. According to our natural progressive MS history, early clinical features are predictors of MS disability accrual.

[Supporting the adaptation to the announcement of multiple sclerosis]

Multiple sclerosis (MS) is a disease that most often begins in young adulthood. With at least 2,500 new cases diagnosed each year in France, it is the leading cause of severe non-traumatic disability among young adults. The announcement of MS constitutes a brutal intrusion into the life of the subject. The carers accompany the process of cognitive and emotional adjustment that is inevitable in order to learn to live with the disease.

Diagnosis of Progressive Multiple Sclerosis From the Imaging Perspective: A Review

Importance

Although magnetic resonance imaging (MRI) is useful for monitoring disease dissemination in space and over time and excluding multiple sclerosis (MS) mimics, there has been less application of MRI to progressive MS, including diagnosing primary progressive (PP) MS and identifying patients with relapsing-remitting (RR) MS who are at risk of developing secondary progressive (SP) MS. This review addresses clinical application of MRI for both diagnosis and prognosis of progressive MS.

Observations

Although nonspecific, some spinal cord imaging features (diffuse abnormalities and lesions involving gray matter [GM] and ≥2 white matter columns) are typical of PPMS. In patients with PPMS and those with relapse-onset MS, location of lesions in critical central nervous system regions (spinal cord, infratentorial regions, and GM) and MRI-detected high inflammatory activity in the first years after diagnosis are risk factors for long-term disability and future progressive disease course. These measures are evaluable in clinical practice. In patients with established MS, GM involvement and neurodegeneration are associated with accelerated clinical worsening. Subpial demyelination and slowly expanding lesions are novel indicators of progressive MS.

Conclusions and Relevance

Diagnosis of PPMS is more challenging than diagnosis of RRMS. No qualitative clinical, immunological, histopathological, or neuroimaging features differentiate PPMS and SPMS; both are characterized by imaging findings reflecting neurodegeneration and are also impacted by aging and comorbidities. Unmet diagnostic needs include identification of MRI markers capable of distinguishing PPMS from RRMS and predicting the evolution of RRMS to SPMS. Integration of multiple parameters will likely be essential to achieve these aims.

The time to develop treatments for diabetic neuropathy

BACKGROUND

Diabetic neuropathy is a multifaceted condition affecting up to 50% of individuals with long standing diabetes. The most common presentation is peripheral diabetic sensory neuropathy (DPN).

METHODS

We carried out a systematic review of papers dealing with diabetic neuropathy on Pubmed in addition to a targeted Google search.Search terms included small fiber neuropathy,diffuse peripheral neuropathy, quantitative sensory testing, nerve conduction testing, intra-epidermal nerve fiber density, corneal confocal reflectance microscopy, aldose reductase inhbitors, nerve growth factor, alpha-lipoic acid, ruboxistaurin, nerve growth factor antibody, and cibinetide.

RESULTS

Over the past half century, there have been a number of agents undergoing unsuccessful trials for treatment of DPN.There are several approved agents for relief of pain caused by diabetic neuropathy, but these do not affect the pathologic process.

EXPERT OPINION

The failure to find treatments for diabetic neuropathy can be ascribed to (1) the complexity of design of studies and (2) the slow progression of the condition, necessitating long duration trials to prove efficacy.We propose a modification of the regulatory process to permit early introduction of agents with demonstrated safety and suggestion of benefit as well as prolongation of marketing exclusivity while long term trials are in progress to prove efficacy.

NLRP3 inflammasome as prognostic factor and therapeutic target in primary progressive multiple sclerosis patients

Primary progressive multiple sclerosis is a poorly understood disease entity with no specific prognostic biomarkers and scarce therapeutic options. We aimed to identify disease activity biomarkers in multiple sclerosis by performing an RNA sequencing approach in peripheral blood mononuclear cells from a discovery cohort of 44 untreated patients with multiple sclerosis belonging to different clinical forms and activity phases of the disease, and 12 healthy control subjects. A validation cohort of 58 patients with multiple sclerosis and 26 healthy control subjects was included in the study to replicate the RNA sequencing findings. The RNA sequencing revealed an interleukin 1 beta (IL1B) signature in patients with primary progressive multiple sclerosis. Subsequent immunophenotyping pointed to blood monocytes as responsible for the IL1B signature observed in this group of patients. Functional experiments at baseline measuring apoptosis-associated speck-like protein containing a CARD (ASC) speck formation showed that the NOD-leucine rich repeat and pyrin containing protein 3 (NLRP3) inflammasome was overactive in monocytes from patients with primary progressive multiple sclerosis, and canonical NLRP3 inflammasome activation with a combination of ATP plus lipopolysaccharide was associated with increased IL1B production in this group of patients. Primary progressive multiple sclerosis patients with high IL1B gene expression levels in peripheral blood mononuclear cells progressed significantly faster compared to patients with low IL1B levels based on the time to reach an EDSS of 6.0 and the Multiple Sclerosis Severity Score. In agreement with peripheral blood findings, both NLRP3 and IL1B expression in brain tissue from patients with primary progressive multiple sclerosis was mainly restricted to cells of myeloid lineage. Treatment of mice with a specific NLRP3 inflammasome inhibitor attenuated established experimental autoimmune encephalomyelitis disease severity and improved CNS histopathology. NLRP3 inflammasome-specific inhibition was also effective in reducing axonal damage in a model of lipopolysaccharide-neuroinflammation using organotypic cerebellar cultures. Altogether, these results point to a role of IL1B and the NLRP3 inflammasome as prognostic biomarker and potential therapeutic target, respectively, in patients with primary progressive multiple sclerosis.

Gray Matter Matters: A Longitudinal Magnetic Resonance Voxel-Based Morphometry Study of Primary Progressive Multiple Sclerosis

Background: Multiple Sclerosis (MS) lesions in white matter (WM) are easily detected with conventional MRI which induce inflammation thereby generating contrast. WM lesions do not consistently explain the extent of clinical disability, cognitive impairment, or the source of an exacerbation. Gray matter (GM) structures including the cerebral cortex and various deep nuclei are known to be affected early in Primary Progressive Multiple Sclerosis (PPMS) and drive disease progression, disability, fatigue, and cognitive dysfunction. However, little is known about how rapidly GM lesions develop and accumulate over time.

Objective: The purpose of this study is to analyze the degree and rate of progression in 25 patients with PPMS using voxel-based automated volumetric quantitation.

Methods: This is a retrospective single-center study which includes a cohort of 25 patients with PPMS scanned utilizing NeuroQuant® 3 dimensional voxel-based morphometry (3D VBM) automated analysis and database and restudied after a period of ~1 year (11–14 months). Comparisons with normative data were acquired for whole brain, forebrain parenchyma, cortical GM, hippocampus, thalamus, superior and inferior lateral ventricles. GM volume changes were correlated with their clinical motor and cognitive scores using Extended Disability Status Scales (EDSS) and Montreal Cognitive Assessments (MoCA).

Results: Steep reductions occurred in cerebral cortical GM and deep GM nuclei volumes which correlated with each patient's clinical and cognitive impairment. The median observed percentile volume losses were statistically significant compared with the 50th percentile for each GM component. Longitudinal assessments of an unselected sample of one dozen patients involved in the PPMS study showed prominent losses occurring mainly in cortical GM and hippocampus which were reflected in their EDSS and MoCA. The longitudinal results were compared with a similar sample of patients having Relapsing MS (RMS) whose GM values were largely in normal range, annualized volume GM changes were much less, while WM hyperintensities were in abnormal range in half the unselected cases.

Conclusions: Knowledge of the degree and rapidity with which cortical atrophy and deep GM volume loss develops clarifies the source of progressive cognitive and clinical decline in PPMS.

A Descriptive Cross-Sectional Study of Manipulative Dexterity on Different Subtypes of Multiple Sclerosis

Background

Manipulative dexterity impairments affect 76% of individuals with multiple sclerosis (MS). Patients with MS can experience reduced skill when performing both basic activities of daily living and instrumental activities of daily living. Many studies consider that physical rehabilitation leads to a decrease in the level of disability, especially at the mild and moderate stages of the disease. However, most studies fail to distinguish between the different MS subtypes.

Purpose

Our aims were (1) to describe the manipulative skills of people according to the different subtypes of MS, (2) to analyze the correlation between dexterity and self-perception variables, and (3) to identify possible predictors of functionality. Study Design. A descriptive cross-sectional study.

Methods

30 individuals with MS. The measurement tools used were the ABILHAND, the Purdue Pegboard Test (PPT), the Nine-Hole Peg Test, and the Box and Block Test.

Results

All subtypes of MS obtained lower scores for manipulative dexterity compared to normal skill levels, with individuals with primary progressive MS displaying the lowest values. However, the analysis of differences between the different subtypes did not reveal statistically significant intragroup differences. In addition, differences were found regarding the effect size of practically all the variables analyzed for both manipulative dexterity (PPT, NHPT, and BBT) and the self-perception of ADLs (ABILHAND), for which high values (d _r = 0.72) and very high values (d _r = 1.46) were obtained.

Conclusions

Although no significant differences were found between the different types of MS, the assessment of manual dexterity and perceived efficacy of daily activities must be considered as prognostic factors in the progression of the disease. These findings may help support further research on targeted interventions to improve dexterity deficiencies, as well as promote an improved quality of therapeutic interventions.

Inclusion of the Symbol Digit Modalities Test in a revised assessment of 'no evidence of disease activity-4 (NEDA-4)' in Latin-American patients with multiple sclerosis

BACKGROUND

In relapsing-remitting multiple sclerosis (RRMS), no evidence of disease activity-3 (NEDA-3) is defined as the absence of: (1) relapses; (2) disability progression; (3) MRI activity (new/enlarged T2 lesions and/or gadolinium-enhanced T1 lesions). NEDA-4 status is defined as meeting all NEDA-3 criteria plus having an annualized percentage brain volume change (a-PBVC) >-0.4%. In individual patients, brain volume assessment is confounded with normal aging, methodological limitations and fluid-shift related fluctuations in brain volume. Cognitive impairment has been proposed as another component that should be integrated into therapeutic algorithms for RRMS. We aim to determine the proportion of patients failing to meet NEDA-4 criteria and to appraise whether the Symbol Digit Modalities Test (SDMT) is capable of replacing a-PBVC as one of the components of NEDA-4. We hypothesize that NEDA-4 has the potential to capture the impact of DMT therapies in RRMS.

METHODS

Forty-five patients were prospectively followed 1 and 2 years after their baseline assessment at the University of Chile Hospital. SIENA software was used to assess a-PBVC.

RESULTS

At baseline, the patients had a mean age of 33.0 years (range 18-57), disease duration of 1.9 years (0.4-4), Expanded Disability Status Scale score of 1.3 (0-4), and 67% were female. The majority had RRMS (91% while 9% had clinically isolated syndrome (CIS)). Seventy-three percent were on the so-called first line DMTs such as interferons (53%), glatiramer acetate (13%), teriflunomide (9%), and 18% were on fingolimod. There was a serial decline in the proportion of NEDA: after 1 and 2 years of follow-up 60% and 47% met NEDA-3 status, and 38% and 27% met NEDA-4, respectively. At the last follow-up 21% remained on interferons, 47% were now on fingolimod, 4% on alemtuzumab and 2% on natalizumab. At year 1 and year 2, with the replacement of a-PBVC by SDMT, 53% and 40% of patients achieved a putative NEDA-4 status, respectively.

CONCLUSION

Brain volumetric MRI has yet to be translated into clinical practice and SDMT may qualify as the fourth component of NEDA-4 definition. NEDA-4 has the potential to capture the impact of DMT therapies in RRMS earlier in the disease course of RRMS.

Disease activity impacts disability progression in primary progressive multiple sclerosis

BACKGROUND

Although solid information on the natural history of primary progressive multiple sclerosis (PPMS) is available, evidence regarding impact of disease activity on PPMS progression remains controversial.

OBJECTIVE

To describe the clinical characteristics, presence or absence of MRI activity, and natural history of a PPMS cohort from two referral centers in Argentina and assess whether clinical and/or radiological disease activity correlated with disability worsening.

METHODS

Retrospective study conducted at two MS clinics in Buenos Aires, Argentina, through comparative analysis of patients with and without evidence of disease activity.

RESULTS

Clinical and/or radiologic activity was presented in 56 (31%) of 178 patients. When stratified by age at onset, we found that for every 10 years of increase in age at onset, risk of reaching EDSS scores of 4 and 6 increased by 26% and 31%, respectively (EDSS 4: HR 1.26, CI 95%: 1.06-1.50; EDSS 6: HR 1.31, CI 95%: 1.06-1.62). Patients who presented clinical exacerbations reached EDSS scores of 6, 7 and 8 faster than those without associated exacerbations (p = 0.009, p = 0.016 and p = 0.001, respectively). Likewise, patients who presented gadolinium-enhancing lesions during the course of disease reached EDSS scores of 7 earlier (p = 0.002).

CONCLUSION

Older age at onset and presence of clinical and/or radiological disease activity correlated with accelerated disability progression in this cohort of PPMS patients.

Cox regression increases power to detect genotype-phenotype associations in genomic studies using the electronic health record

Background

The growth of DNA biobanks linked to data from electronic health records (EHRs) has enabled the discovery of numerous associations between genomic variants and clinical phenotypes. Nonetheless, although clinical data are generally longitudinal, standard approaches for detecting genotype-phenotype associations in such linked data, notably logistic regression, do not naturally account for variation in the period of follow-up or the time at which an event occurs. Here we explored the advantages of quantifying associations using Cox proportional hazards regression, which can account for the age at which a patient first visited the healthcare system (left truncation) and the age at which a patient either last visited the healthcare system or acquired a particular phenotype (right censoring).

Results

In comprehensive simulations, we found that, compared to logistic regression, Cox regression had greater power at equivalent Type I error. We then scanned for genotype-phenotype associations using logistic regression and Cox regression on 50 phenotypes derived from the EHRs of 49,792 genotyped individuals. Consistent with the findings from our simulations, Cox regression had approximately 10% greater relative sensitivity for detecting known associations from the NHGRI-EBI GWAS Catalog. In terms of effect sizes, the hazard ratios estimated by Cox regression were strongly correlated with the odds ratios estimated by logistic regression.

Conclusions

As longitudinal health-related data continue to grow, Cox regression may improve our ability to identify the genetic basis for a wide range of human phenotypes.

Transcranial Magnetic Stimulation as a Potential Biomarker in Multiple Sclerosis: A Systematic Review with Recommendations for Future Research

Multiple sclerosis (MS) is a demyelinating disorder of the central nervous system. Disease progression is variable and unpredictable, warranting the development of biomarkers of disease status. Transcranial magnetic stimulation (TMS) is a noninvasive method used to study the human motor system, which has shown potential in MS research. However, few reviews have summarized the use of TMS combined with clinical measures of MS and no work has comprehensively assessed study quality. This review explored the viability of TMS as a biomarker in studies of MS examining disease severity, cognitive impairment, motor impairment, or fatigue. Methodological quality and risk of bias were evaluated in studies meeting selection criteria. After screening 1603 records, 30 were included for review. All studies showed high risk of bias, attributed largely to issues surrounding sample size justification, experimenter blinding, and failure to account for key potential confounding variables. Central motor conduction time and motor-evoked potentials were the most commonly used TMS techniques and showed relationships with disease severity, motor impairment, and fatigue. Short-latency afferent inhibition was the only outcome related to cognitive impairment. Although there is insufficient evidence for TMS in clinical assessments of MS, this review serves as a template to inform future research.

Prolactin is Not Associated with Disability and Clinical Forms in Patients with Multiple Sclerosis

An association between prolactinemia with disability, clinical forms, and sex of patients with multiple sclerosis (MS) remains unclear. The aim of this study was to evaluate the association of prolactin with clinical forms and accumulating disability over time in patients with MS. A longitudinal study was carried out with 101 patients with relapsing-remitting MS (RRMS) and 19 with progressive forms of MS (ProgMS). The disability over time, as well as prolactin and ferritin serum levels were evaluated at baseline (T0), 8-month follow-up (T8), and 16-month follow-up. The disability at T0, T8, and T16 was higher among patients with ProgMS than those with RRMS. Prolactin and ferritin levels did not differ over time between both groups. Initially, prolactin was associated with MS disability. After introducing age and sex, the effects of prolactin on disability were no longer significant. Prolactin was associated with age and sex, whereby age was positively associated with disability. In the same way, after introducing age and sex, the effects of diagnosis on prolactin levels, as well as the association between prolactin and ferritin, were no longer significant (P = 0.563 and P = 0.599, respectively). Moreover, 21.6% of the variance in the disability was predicted by age (P < 0.001), and sex (P = 0.049), while prolactin was not significant. In conclusion, the effects of prolactin on the disability and clinical forms of MS patients may be spurious results because those correlations reflect the positive associations of age with the disability and the negative association of age with prolactin.

Cost-effectiveness analysis of escalating to natalizumab or switching among immunomodulators in relapsing-remitting multiple sclerosis in Italy

Background

Published literature suggests that early treatment with natalizumab (“escalation strategy”) is more effective than switch within the same class of immunomodulators (interferons/glatiramer acetate, “switching strategy”) in relapsing-remitting multiple sclerosis (RRMS) patients who failed first-line self-injectable disease-modifying treatment (DMT). The present analysis aims to evaluate the cost-effectiveness profile of escalation strategy vs. switching strategy, adopting the Italian societal perspective.

Methods

A lifetime horizon Markov model was developed to compare early escalation to natalizumab vs. switching among immunomodulators, followed by subsequent escalation to natalizumab. The two compared treatment algorithms were: a) early escalation until progression to Expanded Disability Status Scale (EDSS) = 7.0 vs. b) switching until EDSS = 4.0, followed by escalation until EDSS = 7.0. The model analyzed social costs, quality-adjusted survival and effects of therapies in prolonging time without disability progression and burden of relapses. Clinical data were mainly extracted from a published observational study.

Results

Lifetime costs of early escalation to natalizumab and switching among immunomodulators amounted to €699,700 and €718,600 per patient, respectively. Early escalation was associated with prolonged quality-adjusted survival (11.19 vs. 9.67 QALYs, + 15.8%). A slight overall survival increase was also observed (20.10 vs. 19.67 life years). Both deterministic and probabilistic sensitivity analyses confirmed the robustness of findings.

Conclusions

Adopting the Italian social perspective, early escalation to natalizumab is dominant vs. switching among immunomodulators, in RRMS patients who do not respond adequately to conventional immunomodulators.

Electronic supplementary material

The online version of this article (10.1186/s12913-019-4264-1) contains supplementary material, which is available to authorized users.

Early Clinical Features, Time to Secondary Progression, and Disability Milestones in Polish Multiple Sclerosis Patients

Background and Objectives: Determining the clinical course of multiple sclerosis (MS) and prediction of long-term disability can be a big challenge. To determine early clinical features of MS, their influence on long-term disability progression, and time to transition from relapsing-remitting MS (RRMS) to secondary progressive MS (SPMS), a cohort of Polish patients was studied. Materials and Methods: We retrospectively evaluated 375 Polish MS patients based on data from available medical records. We assessed early clinical MS features and the relationship between demographics and time from disease onset to attainment of 4 and 6 points on the Expanded Disability Status Scale (EDSS), as well as time to conversion from RRMS to SPMS. Results: The differences between initial MS variants were significantly associated with gender, age at disease onset, number and type of the first symptoms, and rate of the disability accrual. Mean times from disease onset to attainment of EDSS 4 and 6 were significantly influenced by the disease variant, age at onset, gender, degree of recovery from the initial symptoms, and first inter-bouts interval. The mean time to secondary progression was significantly influenced by the number and type of the first symptoms of RRMS. Conclusions: Early clinical features of MS are important in determining the disease variant, the time to transition from RRMS to SPMS, as well as predicting the disability accumulation of patients. Despite the small differences regarding the first MS symptoms, the disability outcomes in the cohort of Polish patients are similar to other regions of the world.

CSF Neurofilament Light Chain Levels in Primary Progressive MS: Signs of Axonal Neurodegeneration

Objectives: Elevated neurofilament light chain (NFL) levels within the cerebrospinal fluid (CSF) are a biomarker representing axonal neurodegeneration in rapid progressive neurodegenerative diseases such as amyotrophic lateral sclerosis (ALS). It is unclear to what extent the levels of NFL increase in the CSF (CSF-NFL) in a chronic neuroinflammatory process with axonal neurodegeneration, as found in primary progressive multiple sclerosis (PPMS).

Methods: We used a multicenter approach to statistically compare CSF-NFL levels between PPMS patients (n = 50), ALS patients (n = 50), and healthy controls (n = 50). Clinical findings, including disease duration, expanded disability status scale (EDSS), electrophysiological recordings such as visual evoked potentials or spinal and cerebral MRI, and previously administered treatment were selected as experimental parameters retrospectively.

Results: Median [range] CSF-NFL concentrations in PPMS patients were significantly higher than in the controls [1724 (799–4275) pg/ml vs. 1202 (612–2934) pg/ml, p = 0.015], and significantly lower compared to ALS patients [1724 (799–4275) pg/ml vs. 10238 (2610–35138) pg/ml, p < 0.001]. There was no correlation between CSF-NFL and disease duration (p = 0.5), EDSS (p = 0.2) or treatment (p = 0.3).

Conclusion: We conclude that CSF-NFL may mirror the proposed slow axonal degeneration in PPMS, but does not reflect the disease severity.

A contemporary study of mortality in the multiple sclerosis population of south east Wales

BACKGROUND

Mortality studies in multiple sclerosis (MS) are valuable to identify changing disease patterns and inform clinical management. This study examines mortality in a British MS cohort.

METHODS

Patients were selected from the southeast Wales MS registry. Hazard of death was analysed using Cox proportional hazards regression, adjusted for onset age, annualised relapse rate, initial disease course, time to EDSS 4.0, sex, socioeconomic status, and onset year. Age- and sex-stratified standardised mortality ratios (SMRs) were calculated by EDSS scores.

RESULTS

Median time from MS diagnosis to death was 35.5 years and median age 73.9. Older onset age (hazard ratio [HR] 1.05, 95% confidence interval 1.03-1.06) was associated with increased hazard of death. Primary progressive course was associated with increased hazard of death in women (HR 2.04, 1.15-3.63) but not men (HR 1.23, 0.61-2.47). Slow time to EDSS 4.0 (HR 0.41, 0.28-0.60) and high socioeconomic status (HR 0.54, 0.37-0.79) were associated with reduced hazard of death. SMR increased from EDSS 6.0 (3.86, 2.63-5.47) but more substantially at EDSS 8.0 (22.17, 18.20-26.75).

CONCLUSIONS

Risk of death in MS varies substantially with degree of disability. This has important implications for clinical management and health economic modelling.

The MRI central vein marker; differentiating PPMS from RRMS and ischemic SVD

Objective

To determine whether the assessment of brain white matter lesion (WML) central veins differentiate patients with primary progressive MS (PPMS) from relapsing-remitting MS (RRMS) and ischemic small vessel disease (SVD) using 3T MRI.

Methods

In this cross-sectional study, 71 patients with PPMS, RRMS, and SVD were imaged using a T2*-weighted sequence. Two blinded raters identified the total number of WMLs, proportion of WMLs in periventricular, deep white matter (DWM) and juxtacortical regions, and proportion of WMLs with central veins in all patient groups. The proportions were compared between disease groups, including effect sizes. MS or SVD was categorized using a threshold of ≥40% WMLs with central veins as indicative of MS. Interrater and intrarater reproducibility was calculated.

Results

The mean proportion of WMLs with central veins was 68.4% in PPMS, 74.3% in RRMS, and 4.7% in SVD. The difference in proportions between PPMS and SVD groups was significant (p < 0.0005; effect size: 3.8) but not significant between MS subtypes (p = 0.3; effect size: 0.29). Distribution of WMLs was similar across both MS groups, but despite SVD patients having more DWM lesions than PPMS patients, proportions of WMLs with central veins remained low (2.75% in SVD; 62.5% in PPMS). Interrater and intrarater reproducibility comparing proportions of WMLs with central veins across all patients was 0.86 and 0.90, respectively. Level of agreement between the proportion of WML central veins and established diagnosis was 0.84 and 0.82 for each rater.

Conclusions

WML central veins could be used to differentiate PPMS from SVD but not between MS subtypes.

Brain and spinal cord MRI lesions in primary progressive vs. relapsing-remitting multiple sclerosis

Background

Primary progressive (PP) multiple sclerosis (MS) is considered a clinically distinct entity from the spectrum of relapsing-remitting (RR) forms of the disease.

Objective

To compare the presence of brain and spinal cord lesions between PP and RR subjects.

Methods

We studied people with PPMS [n = 40, 17 (42.5%) men, age 50.7 ± 7.7 years, disease duration 10.1 ± 7.4 years, Expanded Disability Status Scale (EDSS) score 4.6 ± 2.1] and RRMS [n = 40, 12 (30%) men, age 47.9 ± 4.2, disease duration 13.7 ± 5.9, EDSS 1.7 ± 1.3]. MRI of the brain and full spinal cord at 1.5T was analyzed to define patients having: 1. brain only, 2. spinal cord only, or 3. brain and spinal cord MS lesions.

Results

Lesions in the brain only were less common in PP (n = 1, 2.5% of people) than RR (n = 10, 25%) (Fisher's exact p = 0.007). Lesions in the spinal cord only (PP: n = 6, 15%, RR: n = 3, 7.5%, p = 0.481) or brain plus spinal cord (PP: n = 33, 83%, RR: n = 27, 68%, p = 0.196) were similar between groups. PP had higher EDSS and timed 25-ft walk (Wilcoxon tests, both p < 0.001), higher age (t-test p = 0.049), lower disease duration (t-test, p = 0.02), and a similar sex ratio (Fisher's exact p = 0.352) vs. RR.

Conclusions

We report a topographic difference in MRI lesion involvement between PPMS and RRMS. Lesions restricted to the brain are more common in RRMS. These findings provide support to the notion that PP may have features distinctive from the RR spectrum of the disease. Longitudinal comparisons and quantitative MRI analysis would be necessary to confirm and extend these results.

Testosterone and estrogen in multiple sclerosis: from pathophysiology to therapeutics

INTRODUCTION

Neuroprotection and remyelination are two unmet needs in the treatment of multiple sclerosis (MS). Therapeutic potential has been identified with sexual hormones, supported in women by a decrease in MS activity during the pregnancy, in men by a greater severity of symptoms and a faster progression than in women. Areas covered: The therapeutic effect of testosterone and estrogens is reviewed. Both hormones have demonstrated an anti-inflammatory effect. Testosterone has an effect in protecting neurons in culture against glutamate-induced toxicity and oxidative stress, and stimulates myelin formation and regeneration mediated through the neural androgen receptor. In experimental autoimmune encephalomyelitis model, estrogens significantly decrease inflammation in the central nervous system via ERα, while its action on ERβ leads to myelin and axon reparation. Estriol therapy in two phase 2 trials showed a decrease in clinical disease activity and inflammatory parameters in MRI. However, evidence of a therapeutic effect of testosterone is scarce. Expert commentary: Phase 3 trials with estriol as an add-on supplementation are now mandatory. Testosterone is another candidate to be tested in phase 2 trials. These hormones should be considered as an adjunctive therapy. New validated tools are needed to assess their effect on neuroprotection and remyelination.

Societal costs of multiple sclerosis in Ireland

AIMS

This paper evaluates the impact of multiple sclerosis (MS) in Ireland, and estimates the associated direct, indirect, and intangible costs to society based on a large nationally representative sample.

MATERIALS AND METHODS

A questionnaire was developed to capture the demographics, disease characteristics, healthcare use, informal care, employment, and wellbeing. Referencing international studies, standardized survey instruments were included (e.g. CSRI, MFIS-5, EQ-5D) or adapted (EDSS) for inclusion in an online survey platform. Recruitment was directed at people with MS via the MS Society mailing list and social media platforms, as well as in traditional media. The economic costing was primarily conducted using a 'bottom-up' methodology, and national estimates were achieved using 'prevalence-based' extrapolation.

RESULTS

A total of 594 people completed the survey in full. The sample had geographic, disease, and demographic characteristics indicating good representativeness. At an individual level, average societal cost was estimated at €47,683; the average annual costs for those with mild, moderate, and severe MS were calculated as €34,942, €57,857, and €100,554, respectively. For a total Irish MS population of 9,000, the total societal costs of MS amounted to €429m. Direct costs accounted for just 30% of the total societal costs, indirect costs amounted to 50% of the total, and intangible or QoL costs represented 20%. The societal cost associated with a relapse in the sample is estimated as €2,438.

LIMITATIONS AND CONCLUSIONS

The findings highlight that up to 70% of the total costs associated with MS are not routinely counted. These "hidden" costs are higher in Ireland than the rest of Europe, due in part to significantly lower levels of workforce participation, a higher likelihood of permanent workforce withdrawal, and higher levels of informal care needs. The relationship between disease progression and costs emphasize the societal importance of managing and slowing the progression of the illness.

CSF profile in primary progressive multiple sclerosis: Re-exploring the basics

Objective

The aim of this study was to report the basic cerebrospinal fluid (CSF) profile in patients with primary progressive multiple sclerosis (PPMS).

Methods

The results of CSF analysis from 254 patients with PPMS were collected at four university hospitals in Germany. Routine CSF parameters and different indices of intrathecal immunoglobulin synthesis were evaluated. We assessed possible correlations between the various CSF parameters and the expanded disability status scale (EDSS) both at the time of lumbar puncture and during the course of the disease.

Results

The median cell count and albumin concentration in the CSF did not deviate from normal values. The CSF-serum albumin-quotient (Q_ALB) was elevated in 29.6% of the patients, while intrathecal immunoglobulin G (IgG) oligoclonal bands (OCBs) were detected in 91.1% of the patients. CSF-lactate levels as well as local IgM- and IgA-synthesis were correlated with the yearly disease progression rate, as assessed by EDSS.

Conclusion

We present the results of the hitherto largest and most detailed CSF biomarker profile in a cohort of 254 patients with PPMS. As reported previously, OCBs are the most sensitive marker for intrathecal IgG synthesis. CSF-lactate concentrations are positively correlated with the progression rate, which might suggest that mitochondrial dysfunction plays a relevant role in PPMS. The negative correlation between intrathecally produced IgM and IgA and disease progression may indicate their hitherto unexplored protective role.

Imaging primary progressive multiple sclerosis: the contribution of structural, metabolic, and functional MRI techniques

Patients with primary progressive multiple sclerosis (PPMS) typically experience a progressive disease course from onset, leading to the accumulation of severe neurological disability. This is in contrast with the observation that the burden and activity of lesions on conventional magnetic resonance imaging (MRI) scans of the brain are much lower in patients with PPMS than in those with other less disabling forms of the disease. Studies with structural and functional MRI techniques are providing relevant contributions to the understanding of the mechanisms underlying the accumulatio n of irreversible neurological deficits in patients with PPMS. The results of these studies underpin that the main factors possibly explaining the clinical/MRI discrepancy observed in patients with PPMS include the presence of a diffuse tissue damage that is beyond the resolution of conventional imaging, the extent of cervical cord damage, and the impairment of the adaptive capacity of the cortex to limit the functional consequences of subcortical pathology.

Progressive multiple sclerosis: from pathogenic mechanisms to treatment

During the past decades, better understanding of relapsing-remitting multiple sclerosis disease mechanisms have led to the development of several disease-modifying therapies, reducing relapse rates and severity, through immune system modulation or suppression. In contrast, current therapeutic options for progressive multiple sclerosis remain comparatively disappointing and challenging. One possible explanation is a lack of understanding of pathogenic mechanisms driving progressive multiple sclerosis. Furthermore, diagnosis is usually retrospective, based on history of gradual neurological worsening with or without occasional relapses, minor remissions or plateaus. In addition, imaging methods as well as biomarkers are not well established. Magnetic resonance imaging studies in progressive multiple sclerosis show decreased blood-brain barrier permeability, probably reflecting compartmentalization of inflammation behind a relatively intact blood-brain barrier. Interestingly, a spectrum of inflammatory cell types infiltrates the leptomeninges during subpial cortical demyelination. Indeed, recent magnetic resonance imaging studies show leptomeningeal contrast enhancement in subjects with progressive multiple sclerosis, possibly representing an in vivo marker of inflammation associated to subpial demyelination. Treatments for progressive disease depend on underlying mechanisms causing central nervous system damage. Immunity sheltered behind an intact blood-brain barrier, energy failure, and membrane channel dysfunction may be key processes in progressive disease. Interfering with these mechanisms may provide neuroprotection and prevent disability progression, while potentially restoring activity and conduction along damaged axons by repairing myelin. Although most previous clinical trials in progressive multiple sclerosis have yielded disappointing results, important lessons have been learnt, improving the design of novel ones. This review discusses mechanisms involved in progressive multiple sclerosis, correlations between histopathology and magnetic resonance imaging studies, along with possible new therapeutic approaches.

A contemporary profile of primary progressive multiple sclerosis participants from the NARCOMS Registry

BACKGROUND

Primary progressive multiple sclerosis (PPMS) represents 10%-15% of all multiple sclerosis (MS) diagnoses. Information regarding socio-demographic and clinical characteristics of persons with PPMS is limited.

OBJECTIVE

To characterize persons with PPMS in the North American Research Committee on Multiple Sclerosis (NARCOMS) Registry.

METHODS

We compared demographic and health-related characteristics of NARCOMS Registry participants reporting PPMS in the spring 2015 update survey with those reporting relapsing-remitting multiple sclerosis (RRMS) and secondary progressive multiple sclerosis (SPMS), with characteristics of published PPMS cohorts.

RESULTS

Of 8004 responders, 6774 self-reported a clinical course of PPMS, SPMS, or RRMS. The PPMS cohort ( n = 632, 9.3%) reported a mean (standard deviation (SD)) age of 64.3 (8.9) years; 62.7% were female; the SPMS and RRMS cohorts were younger and had a higher proportion of females. The NARCOMS PPMS cohort differed in age, time from onset and diagnosis, and proportion of females compared to population-based and clinical trial cohorts. Median (25%, 75%) number of comorbidities was 2 (1, 2) for each cohort with vascular comorbidities being most frequently reported.

CONCLUSION

The NARCOMS population provides a different perspective on persons with PPMS than clinical trials. A better understanding of the characteristics of persons with PPMS may help address unmet needs in this population.

The relationship between relapse, impairment and disability in multiple sclerosis

Objective: To describe the spatial relationship between relapse and disability in multiple sclerosis (MS).

Methods: 141 relapse onset MS patients were studied. For each patient an examination was performed and a relapse history obtained. Multivariate logistic regression examined whether there was an association between localizing clinical signs and a history of relevant relapse in order to explore the spatial relationship between relapse and subsequent disability.

Results: The presence of impaired vision or sensation was independently associated with a history of one or more anatomically related relapses. The presence of weakness or cerebellar ataxia in a limb was not associated with a single relevant relapse but was associated with multiple relevant relapses. A history of multiple episodes of weakness or ataxia in the same limb was uncommon.

Conclusions: Our data suggest that motor pathways are relatively resistant to chronic impairment from acute relapse, whereas afferent pathways are more susceptible. This, in combination with prominent usage of the Expanded Disability Status Scale, which is dependent on mobility and motor function at higher scores, may explain the paradox between natural history studies that suggest relapses are irrelevant to long-term disability and shorter studies at lower disability levels suggesting relapses are responsible for disability accumulation.

Smoking does not influence disability accumulation in primary progressive multiple sclerosis

BACKGROUND AND PURPOSE

The modifiable risk factor cigarette smoking has been associated with an increased risk of developing multiple sclerosis (MS) and with disease activity in relapsing-remitting MS. However, less is known about the effect of smoking on disease progression in progressive MS. Here the association between cigarette smoking and disability accumulation in primary progressive MS (PPMS) is investigated.

METHODS

Kaplan-Meier survival analyses and Cox proportional hazard modelling were used to investigate the influence of cigarette smoking on the risk of reaching Expanded Disability Status Scale (EDSS) 4 and 6 as well as the time from EDSS 4 to 6 in patients with PPMS.

RESULTS

In all, 416 patients with PPMS and available smoking history were identified. Median time to EDSS 4 was 4 years in ever-smokers and 5 years in never-smokers (P = 0.27), and it was 9 years to EDSS 6 in both ever-smokers and never-smokers (P = 0.48). Smokers were not at increased risk of faster progression to EDSS 4, 6 and from EDSS 4 to 6. Age at disease onset was the strongest risk factor for progression to EDSS 4, 6 and from EDSS 4 to 6.

CONCLUSIONS

Our investigation of a large and well-characterized population based PPMS cohort suggests that cigarette smoking does not influence disability accumulation in PPMS. Our findings support the idea that PPMS is driven by different underlying pathomechanisms than relapsing-remitting MS.