Benign multiple sclerosis: a need for a consensus

Baseline serum neurofilament light chain levels differentiate aggressive from benign forms of relapsing-remitting multiple sclerosis: a 20-year follow-up cohort

BACKGROUND AND OBJECTIVES

Serum biomarkers are emerging as useful prognostic tools for multiple sclerosis (MS); however, long-term studies are lacking. We aimed to evaluate the long-term prognostic value of the serum levels of neurofilament light chain (NfL), total tau, glial fibrillary acidic protein (GFAP), and chitinase 3-like-1 (CHI3L1) measured close to the time of MS onset.

METHODS

In this retrospective, exploratory, observational, case and controls study, patients with relapsing-remitting MS (RRMS) with available baseline serum samples and prospectively follow-up in our MS unit for a long time were selected based on their clinical evolution to form two groups: (1) a benign RRMS (bRRMS) group, defined as patients with an Expanded Disability Status Scale (EDSS) score of ≤ 3 at ≥ 10 years of follow-up; (2) an aggressive RRMS (aRRMS) group, defined as patients with an EDSS score of ≥ 6 at ≤ 15 years of follow-up. An age-matched healthy control (HC) group was selected. NfL, total tau, and GFAP serum levels were quantified using a single-molecule array (SIMOA), and CHI3L1 was quantified using ELISA.

RESULTS

Thirty-one patients with bRRMS, 19 with aRRMS, and 10 HC were included. The median follow-up time from sample collection was 17.74 years (interquartile range, 14.60-20.37). Bivariate and multivariate analyses revealed significantly higher NfL and GFAP levels in the aRRMS group than in the bRRMS group. A receiver operating characteristic curve analysis identified serum NfL level as the most efficient marker for distinguishing aRRMS from bRRMS.

DISCUSSION

This proof-of-concept study comparing benign and aggressive RRMS groups reinforces the potential role of baseline NfL serum levels as a promising long-term disability prognostic marker. In contrast, serum GFAP, total tau, and CHI3L1 levels demonstrated a lower or no ability to differentiate between the long-term outcomes of RRMS.

Gaining Biological Insights through Supervised Data Visualization

Dimensionality reduction-based data visualization is pivotal in comprehending complex biological data. The most common methods, such as PHATE, t-SNE, and UMAP, are unsupervised and therefore reflect the dominant structure in the data, which may be independent of expert-provided labels. Here we introduce a supervised data visualization method called RF-PHATE, which integrates expert knowledge for further exploration of the data. RF-PHATE leverages random forests to capture intricate featurelabel relationships. Extracting information from the forest, RF-PHATE generates low-dimensional visualizations that highlight relevant data relationships while disregarding extraneous features. This approach scales to large datasets and applies to classification and regression. We illustrate RF-PHATE's prowess through three case studies. In a multiple sclerosis study using longitudinal clinical and imaging data, RF-PHATE unveils a sub-group of patients with non-benign relapsingremitting Multiple Sclerosis, demonstrating its aptitude for time-series data. In the context of Raman spectral data, RF-PHATE effectively showcases the impact of antioxidants on diesel exhaust-exposed lung cells, highlighting its proficiency in noisy environments. Furthermore, RF-PHATE aligns established geometric structures with COVID-19 patient outcomes, enriching interpretability in a hierarchical manner. RF-PHATE bridges expert insights and visualizations, promising knowledge generation. Its adaptability, scalability, and noise tolerance underscore its potential for widespread adoption.

Fatigue and health-related quality of life depend on the disability status and clinical course in RRMS

BACKGROUND

Fatigue is a prominent and disabling symptom of multiple sclerosis (MS), impairing quality of life. The disease course of relapsing remitting MS (RRMS) is individual.

OBJECTIVES

We aimed to study the effects of demographic and clinical characteristics, as well as lifestyle risk factors on experienced fatigue and health-related quality of life (HRQoL) among RRMS patients, comparing benign and severe disease types.

METHODS

Altogether 198 Finnish RRMS patients were recruited for this real-life cross-sectional study. Self-reported questionnaires were used to evaluate fatigue and HRQoL by using Fatigue Scale for Motor and Cognitive Functions and 15D health-related quality of life questionnaires. Patients were categorized into subgroups based on the current disability status measured by the Expanded Disability Status Scale (EDSS) cut-off value of 4.5, and by retrospective clinical course divided into benign and aggressive RRMS.

RESULTS

All in all, 73% of the RRMS patients suffered from fatigue. Lower HRQoL had a strong correlation with more prominent fatigue (r = -0.719). Higher EDSS was associated with more prominent fatigue and lower HRQoL in the whole RRMS cohort. Older age at the disease onset was associated with more prominent fatigue and decreased HRQoL in the groups of aggressive RRMS and EDSS > 4.5. In the groups of EDSS ≤ 4.5 and benign RRMS, a higher number of used disease-modifying treatments (DMTs) was associated with more pronounced fatigue and reduced HRQoL. In addition, higher BMI was associated with lower HRQoL in patients with benign RRMS. Side effects (45 %) and lack of efficacy (26 %) were the most common reasons for discontinuing a DMT. Cessation due to side effects was the only reason that was significantly associated with more prominent fatigue and lower HRQoL. Use of nicotine products, gender, or disease duration were not associated with fatigue or HRQoL.

CONCLUSIONS

Individuals with severe RRMS and higher EDSS scores are more prone to experience fatigue and lower HRQoL. In addition, fatigue and lower HRQoL are more commonly observed among RRMS patients with older age at disease onset and in those with multiple DMT switches.

Swept-Source Optical Coherence Tomography Thresholds in Differentiating Clinical Outcomes in a Real-World Cohort of Treatment-Naïve Multiple Sclerosis Patients

This study aimed to determine whether peripapillary retinal nerve fiber layer (pRNFL) and ganglion cell–inner plexiform layer (GCIPL) thickness thresholds for single-time-point swept-source optical coherence tomography (SS-OCT) measures can differentiate the clinical outcomes of treatment-naïve people with multiple sclerosis (pwMS). A total of 275 patients with the clinically isolated syndrome (n = 23), benign MS (n = 8), relapsing–remitting MS (n = 185), secondary progressive MS (n = 28), primary progressive MS (n = 31), and with no history of optic neuritis were included. The mean Expanded Disability Status Scale (EDSS) score was 3.0 ± 1.6. The cut-off values of pRNFL (87 µm and 88 µm) and GCIPL (70 µm) thicknesses have been adopted from previous studies using spectral-domain OCT. PwMS with pRNFL ≤87 µm and ≤88 µm had a longer disease duration, more advanced disability, and more frequently progressive MS variants compared to those with greater pRNFL thicknesses. In distinguishing pwMS with disability greater than or equal to the mean EDSS score (EDSS ≥ 3) from those with less severe disability, GCIPL thickness <70 µm had the highest sensitivity, while pRNFL thickness ≤87 µm had the greatest specificity. The optimal cut-off values differentiating patients with EDSS ≥ 3 from those with less severe disability was 63 µm for GCIPL thickness and 93.5 µm for pRNFL thickness. In conclusion, pRNFL and GCIPL thickness thresholds for single-time-point SS-OCT measurements may be helpful in differentiating the disability status of treatment-naïve pwMS.

Longitudinal Optical Coherence Tomography Measurement of Retinal Ganglion Cell and Nerve Fiber Layer to Assess Benign Course in Multiple Sclerosis

A benign form of multiple sclerosis (BMS) is not easily diagnosed, but changes of the retinal ganglion cell layer-inner plexiform layer (GCL-IPL) and retinal nerve fiber layer (RNFL) may be sensitive to the disease. The aim of this study was to use optical coherence tomography (OCT) to investigate longitudinal changes of GCL-IPL and RNFL in BMS. Eighteen patients with BMS and 22 healthy control (HC) subjects were included, with a mean follow-up period of 32.1 months in BMS and 34.3 months in HC. Mean disease duration in BMS was 23.3 years, with 14 patients left untreated. Unilateral optic neuritis (ON) was found in eight patients. Non-ON eyes showed thinner GCL-IPL layer in the BMS group relative to HC (p < 0.001). The thinning rate of GCL-IPL in non-ON BMS, however, was −0.19 ± 0.15 µm/year vs. 0 ± 0.11 µm/year for HC (p = 0.573, age-adjusted). Thinning rate of RNFL in non-ON BMS was −0.2 ± 0.27 µm/year vs. −0.05 ± 0.3 µm/year for HC (p = 0.454, age adjusted). Conclusions: Thinning rate of the GCL-IPL and RNFL in BMS is similar to the healthy population but differs from the thinning rate in relapsing-remitting MS, presenting a non-invasive OCT-based criterion for assessing a benign course in multiple sclerosis.

Grey matter atrophy in patients with benign multiple sclerosis

BACKGROUND

Brain atrophy appears during the progression of multiple sclerosis (MS) and is associated with the disability caused by the disease.

METHODS

We investigated global and regional grey matter (GM) and white matter (WM) volumes, WM lesion load, and corpus callosum index (CCI), in benign relapsing-remitting MS (BRRMS, n = 35) with and without any treatment and compared those to aggressive relapsing-remitting MS (ARRMS, n = 46). Structures were analyzed by using an automated MRI quantification tool (cNeuro®).

RESULTS

The total brain and cerebral WM volumes were larger in BRRMS than in ARRMS (p = .014, p = .017 respectively). In BRRMS, total brain volumes, regional GM volumes, and CCI were found similar whether or not disease-modifying treatment (DMT) was used. The total (p = .033), as well as subcortical (p = .046) and deep WM (p = .041) lesion load volumes were larger in BRRMS patients without DMT. Cortical GM volumes did not differ between BRRMS and ARRMS, but the volumes of total brain tissue (p = .014) and thalami (p = .003) were larger in patients with BRRMS compared to ARRMS. A positive correlation was found between CCI and whole-brain volume in both BRRMS (r = .73, p < .001) and ARRMS (r = .80, p < .01).

CONCLUSIONS

Thalamic volume is the most prominent measure to differentiate BRRMS and ARRMS. Validation of automated quantification of CCI provides an additional applicable MRI biomarker to detect brain atrophy in MS.

Serum GFAP and NfL levels in benign relapsing-remitting multiple sclerosis

OBJECTIVE

We aimed to investigate serum glial fibrillary acidic protein (GFAP) and serum neurofilament light chain (NfL) levels as potential discriminative biomarkers between benign relapsing-remitting multiple sclerosis (BRRMS) and aggressive relapsing-remitting MS (ARRMS).

METHODS

Serum GFAP and NfL levels were analyzed in patients with BRRMS (n = 34), ARRMS (n = 29), and healthy controls (n = 14) by using Single Molecule Array (Simoa). Patients with ARRMS had been treated with highly effective disease-modifying treatments (DMT) (fingolimod or natalizumab).

RESULTS

Serum GFAP levels in both BRRMS (median 210.19 pg/ml, IQR 163.69-287.19) and in ARRMS (median 188.60 pg/ml, IQR39.23-244.93) were significantly higher (p = 0.035 and p = 0.034, respectively) compared to healthy controls (median 117.93 pg/ml, IQR 60.28-183.83). Serum GFAP levels did not differ between BRRMS and ARRMS. There were no statistical differences in NfL levels between BRRMS, ARRMS and healthy controls. GFAP level was significantly higher (p = 0.04) in BRRMS without DMT (median 216.04 pg/ml, IQR 188.60-274.79) than in those BRRMS patients who had used DMT (median 196.26 pg/ml, IQR 133.33-325.54).

CONCLUSIONS

We found elevated levels of serum GFAP in both BRRMS and ARRMS compared to healthy controls, reflecting astrocytic activation. Serum NfL did not differ between BRRMS and ARRMS, probably due to the stable inflammatory phase of the disease and effective DMT use in ARRMS. Single serum NfL and GFAP measurements cannot separate a patient with BRRMS from effectively treated ARRMS after a long history of the disease, thus consecutive samples are needed in the follow-up.

Spectral-Domain Optical Coherence Tomography Assessment in Treatment-Naïve Patients with Clinically Isolated Syndrome and Different Multiple Sclerosis Types: Findings and Relationship with the Disability Status

This study evaluates the peripapillary retinal nerve fiber layer (pRNFL) thickness and total macular volume (TMV) using spectral-domain optical coherence tomography in treatment naïve patients with the clinically isolated syndrome (CIS) and different multiple sclerosis (MS) types. A total of 126 patients (15 CIS, 65 relapsing-remitting MS, 14 secondary progressive MS, 11 primary progressive MS, 21 benign MS) with or without optic neuritis (ON) history and 63 healthy age-similar controls were assessed. Concerning controls' eyes, pRNFL thickness was significantly reduced in CIS-ON eyes (p < 0.01), while both TMV and pRNFL thickness was decreased in all MS eyes regardless of ON history (p < 0.01). Significant differences in pRNFL thickness and TMV between MS variants were observed for non-ON eyes (p < 0.01), with the lowest values in benign and secondary progressive disease type, respectively. The pRNFL thickness was inversely correlated with Expanded Disability Status Scale (EDSS) score in non-ON subgroups (p < 0.01), whereas TMV was inversely correlated with EDSS score in both ON and non-ON subgroups (p < 0.01). Concluding, pRNFL thinning confirms optic nerve damage in CIS-ON eyes and appears to be disproportionately high with respect to the disability status of benign MS patients. The values of TMV and pRNFL in non-ON eyes significantly correspond to MS course heterogeneity and patients' disability than in ON eyes.

Neuropsychological characteristics of benign multiple sclerosis patients: A two-year matched cohort study

BACKGROUND

The definition of benign multiple sclerosis (BMS) is still debated. It is mainly based on physical status, however, there is an attempt to involve cognitive functioning or paraclinical factors in order to avoid unnecessary long-term treatment with disease-modifying therapies and to identify these subjects in the early stages of the disease. Therefore the aim of our two-year follow-up study was to investigate the pattern of cognitive functioning and depression in patients with BMS compared to treated relapsing-remitting MS (RRMS) patients and healthy controls.

METHODS

A group of 22 BMS patients was tested against matched RRMS patients and healthy controls. All individuals underwent neuropsychological evaluation exploring mood and the cognitive domains most frequently impaired in MS. MS patients were retested at two-year follow-up.

RESULTS

In terms of cognitive functions there were no differences between BMS and RRMS patients either at baseline or at two-year follow-up. Compared to healthy controls BMS patients showed poorer performance in long-term visuo-spatial memory and information processing speed, whereas, complex attention, working memory, long-term verbal memory - despite slower verbal learning - and executive function were found to be intact. RRMS patients showed significant difference in complex attention, long-term visual memory and information processing speed. Cognitive impairment differed in the patient groups in terms of severity. Both patient groups were depressed compared to controls, but significant differences were found only between BMS and healthy individuals.

CONCLUSION

The results of our study confirm that cognitive functions and mood can be affected in MS independent of disease course and disease modifying treatment. The "benign" label should be treated as only a reference to physical status and non-motor symptoms should be routinely monitored. Without receiving therapy it is an existing entity with longstanding minimal disability.

Earnings among people with multiple sclerosis compared to references, in total and by educational level and type of occupation: a population-based cohort study at different points in time

OBJECTIVES

To investigate earnings among people with multiple sclerosis (PwMS) before and after MS diagnosis compared with people without MS, and if identified differences were associated with educational levels and types of occupations. Furthermore, to assess the proportions on sickness absence (SA) and disability pension (DP) in both groups.

DESIGN

Population-based longitudinal cohort study, 10 years before until 5 years after MS diagnosis.

SETTING

Working-age population using microdata linked from nationwide Swedish registers.

PARTICIPANTS

Residents in Sweden in 2004 aged 30-54 years with MS diagnosed in 2003-2006 (n=2553), and references without MS (n=7584) randomly selected by stratified matching.

OUTCOME MEASURES

Quartiles of earnings were calculated for each study year prior to and following the MS diagnosis. Mean earnings, by educational level and type of occupation, before and after diagnosis were compared using t-tests. Tobit regressions investigated the associations of earnings with individual characteristics. The proportions on SA and/or DP, by educational level and type of occupation, for the diagnosis year and 5 years later were compared.

RESULTS

Differences in earnings between PwMS and references were observed beginning 1 year before diagnosis, and increased thereafter. PwMS had lower mean earnings for the diagnosis year (difference=SEK 28 000, p<0.05), and 5 years after diagnosis, this difference had more than doubled (p<0.05). These differences remained after including educational level and type of occupation. Overall, the earnings of PwMS with university education and/or more qualified occupations were most like their reference peers. The proportions on SA and DP were higher among PwMS than the references.

CONCLUSIONS

The results suggest that the PwMS' earnings are lower than the references' beginning shortly before MS diagnosis, with this gap increasing thereafter. Besides SA and DP, the results indicate that educational level and type of occupation are influential determinants of the large heterogeneity of PwMS' earnings.

How common is truly benign MS in a UK population?

OBJECTIVES

The prevalence and definition of benign multiple sclerosis (BMS) remain controversial. Most definitions are based on the Expanded Disability Status Scale (EDSS), not encompassing the wider impact of disease. The explanation for favourable outcomes remains unclear. We aim to provide a detailed characterisation of patients with low EDSS scores at long disease durations.

METHODS

We screened a population-based registry containing 3062 people with MS to identify individuals with unlimited walking ability at disease durations >15 years. A representative cohort underwent detailed clinical assessment and classified as having BMS according to EDSS score <3, no significant fatigue, mood disturbance, cognitive impairment or disrupted employment, and had not received a disease-modifying therapy. We determined patient-reported perceptions of MS status and made comparisons with EDSS-based definitions.

RESULTS

Of 1049 patients with disease duration of >15 years, 200 (19.1%) had most recent EDSS score <4.0. Detailed contemporary clinical assessment of a representative sample of 60 of these patients revealed 48 (80%) had an EDSS score of <4.0, 35 (58%) <3.0 and 16 (27%) <2.0. Only nine (15%) fulfilled our criteria for BMS; impaired cognition (57%) and effects on employment (52%) the most common causes for exclusion. Meanwhile, 33/60 (69%) patients considered their disease benign. Population frequency for BMS was estimated at 2.9% (95% CI 2.0 to 4.1).

CONCLUSIONS

Comprehensive assessment reveals a small minority of people with MS who appear genuinely benign after 15 years. Study of such individuals may uncover insights about disease pathogenesis. However, discrepancy between patient perception and clinician perception of BMS undermines use of the term 'benign' in clinical settings.

Natural history of benign multiple sclerosis: Clinical and HLA correlates in a Western Australian cohort

BACKGROUND

Benign multiple sclerosis (BMS) is a controversial term that has been used for MS patients with minimal disability decades after disease onset. Herein, we evaluated disease status after 20 years in a Western Australian cohort defined as BMS based on an Expanded Disability Status Scale (EDSS) score ≤ 3.0 at 10 years from onset.

METHODS

MS patients with an EDSS score ≤ 3.0 at 10 years from onset and minimum of 20 years follow up were included in the study. The 20-year EDSS score was considered the primary outcome. Associations with demographic and clinical characteristics and HLA-DRB1 genotype were investigated.

RESULTS

Among 120 patients with a benign course at 10 years, 78 (65%) remained benign at the 20-year follow up, but patients with an EDSS ≥ 2.5 were more likely to go on to develop more severe disability in the next decade. When considering factors associated with an increase in EDSS score ≤ 1 from 10 to 20 years, indicating limited progression, apart from the EDSS score at 10 years, poly-symptomatic presentation (p = 0.004) and cerebellar/brainstem mono-symptomatic presentation (p = 0.016) were independently associated with more rapid progression compared with other mono-symptomatic presentations. Carriage of the high risk HLA-DRB1*1501 allele was marginally associated with slower progression.

CONCLUSIONS

In this geographically isolated MS cohort of predominantly Anglo-Celtic origin clinical progression in the benign MS group was similar to that in other published series from Western countries. These results are in keeping with the view that patients labeled as benign MS are part of a heterogeneous continuum of disease progression and do not possess unique clinical characteristics. Possible genetic determinants of a benign course warrant further investigation.

Benign multiple sclerosis: aspects of cognition and neuroimaging

The existence of a benign multiple sclerosis (BMS) form is a controversial subject. Recent studies of these patients reveal different levels of cognitive impairment, despite the apparent preservation of motor function. The objective of this study was to review and analyze a number of publications that discuss the general aspects of this disease form, such as the definition criteria, prevalence, and clinical and neuroimaging markers. A systematic review of published data on BMS up to October 2015 was performed. Thirty-one published articles were analyzed. The estimated frequency of BMS varied between 6% and 73%. Cognitive impairment was recognized as affecting 17% to 47% of the subjects and presented significant correlation with neuroimaging, such as brain atrophy, increased lesion volume in T2 magnetic resonance assay, and regional grey matter atrophy. The current criteria overestimated the frequency of BMS and, for that reason, this highlights the importance of validating the diagnostic methods practiced.

Factors associated with benign multiple sclerosis in the New York State MS Consortium (NYSMSC)

BACKGROUND

This retrospective analysis explored prognostic factors associated with a benign multiple sclerosis (BMS) disease course at baseline and over the 4-year follow-up.

METHODS

Patients from the centralized New York State Multiple Sclerosis Consortium registry were classified as having BMS according to 3 different criteria centered on disease duration and disability. Additional analyses explored prognostic factors associated with BMS using the most conservative disability criteria (Expanded Disability Status Scale ≤2 and disease duration ≥10 years).

RESULTS

Among 6258 patients who fulfilled eligibility criteria, 19.8 % to 33.3 % were characterized as having BMS, at baseline depending on classification criteria used. Positive prognostic factors for BMS at baseline included female sex (p < 0.0001) and younger age at onset (p < 0.0001); negative prognostic factors included progressive-onset type of MS and African-American race. Of the 1237 BMS patients (per most conservative criteria), 742 were followed for a median of 4 years to explore effect of disease-modifying treatment (DMT) on benign status. DMT (p = 0.009) and longer disease duration (p = 0.007) were the only significant positive predictors of maintaining BMS at follow-up. The protective effect was stronger for patients taking DMT at both enrollment and follow-up (OR = 0.71; p = 0.006).

CONCLUSIONS

There is a need for development of more reliable prognostic indicators of BMS. Use of DMT was significantly associated with maintaining a benign disease state.

Benign multiple sclerosis: physical and cognitive impairment follow distinct evolutions

BACKGROUND

Benign multiple sclerosis (BMS) definitions rely on physical disability level but do not account sufficiently for cognitive impairment which, however, is not rare.

OBJECTIVE

To study the evolution of physical disability and cognitive performance of a group of patients with BMS followed at an University Hospital Multiple Sclerosis Center.

METHODS

A consecutive sample of 24 BMS cases (diagnosis according to 2005 McDonald's criteria, relapsing-remitting course, disease duration ≥ 10 years, and expanded disability status scale [EDSS] score ≤ 2.0) and 13 sex- and age-matched non-BMS patients differing from BMS cases for having EDSS score 2.5-5.5 were included. Main outcome measures were as follows: (i) baseline and 5-year follow-up cognitive impairment defined as failure of at least two tests of the administered neuropsychological battery; (ii) EDSS score worsening defined as confirmed increase ≥ 1 point (or 0.5 point if baseline EDSS score = 5.5).

RESULTS

At inclusion, BMS subjects were 41 ± 8 years old and had median EDSS score 1.5 (range 0-2), while non-BMS patients were 46 ± 8 years old and had median EDSS score 3.0 (2.5-5.5). At baseline 16% of patients in both groups were cognitively impaired. After 5 years, EDSS score worsened in 8% of BMS and 46% of non-BMS patients (P = 0.008), while the proportion of cognitively impaired subjects increased to 25% in both groups.

CONCLUSIONS

Patients with BMS had better physical disability outcome at 5 years compared to non-BMS cases. However, cognitive impairment frequency and decline over time appeared similar. Neuropsychological assessment is essential in patients with BMS given the distinct pathways followed by disease progression in cognitive and physical domains.

Benign Multiple Sclerosis is Associated with Reduced Thinning of the Retinal Nerve Fiber and Ganglion Cell Layers in Non-Optic-Neuritis Eyes

Background and Purpose

It is exceedingly difficult to differentiate benign multiple sclerosis (BMS) from relapsing-remitting multiple sclerosis (RRMS) based on clinical characteristics, neuroimaging, and cerebrospinal fluid tests. Optical coherence tomography (OCT) allows quantification of retinal structures, such as the retinal nerve fiber layer (RNFL) thickness, at the optic disc and the ganglion cell layer (GCL) at the macula, on a micrometer scale. It can also be used to trace minor alterations and the progression of neurodegeneration, help predict BMS, and influence the choice of therapy. To utilize OCT to detect the extent of changes of the optic disk and macular microstructure in patients with BMS and RRMS compared to healthy controls (HCs), with special focus on changes related to the presence/absence of optic neuritis (ON).

Methods

Spectral-domain OCT was applied to examine eyes from 36 patients with multiple sclerosis (MS), comprising 11 with BMS and 25 with RRMS, and 34 HCs.

Results

The RNFL and GCL were significantly thinner in eyes previously affected by ON, irrespective of the type of MS (i.e., BMS or RRMS), than in HCs. Significant thinning of the GCL was also observed in non-ON RRMS (and not non-ON BMS) compared to HCs. Correspondingly, a significant association between disease duration and thinning rates of the RNFL and GCL was observed only in non-ON RRMS (-0.54±0.24 and -0.43±0.21 µm/year, mean±SE; p<0.05 for both), and not in non-ON BMS (-0.11±0.27 and -0.24±0.24 µm/year).

Conclusions

The RNFL and GCL were thinner in both ON- and non-ON MS, but the change was more pronounced in ON MS, irrespective of the MS subtype studied herein. GCL thinning and the thinning rate of both the GCL and RNFL were less pronounced in non-ON BMS than in non-ON RRMS. These findings may help to predict the course of BMS.

Does pain in individuals with multiple sclerosis affect employment? A systematic review and meta-analysis

BACKGROUND

Individuals with multiple sclerosis (MS) experience some of the highest unemployment rates among all groups of chronic illnesses. Pain has been found to be a common reason for sick leave or early retirement in healthy populations or other groups with chronic illness; however, there is little awareness regarding the effect of pain on the work status of individuals with MS.

OBJECTIVES

To estimate the extent to which individuals with pain differ in employment status compared with those without pain among MS patients.

METHODS

An extensive systematic review of the scientific literature was performed within the framework of the Cochrane Collaboration to identify studies focusing on the effect of pain on employment in individuals with MS. The following databases were searched: PubMed, EMBASE, PsychInfo, Web of Science, MD Consult and Elsevier, and Science Direct. The methodological quality of studies was assessed using the McMaster Critical Review Form.

RESULTS

Ten articles met the inclusion criteria and were included in the systematic review. Of these studies, five that exhibited clinical, methodological and statistical homogeneity were included in the meta-analysis. The between-groups (pain + versus pain -) pooled random OR of being employed was 0.7 (strong), and was significantly different from unity (95% CI 0.5 to 0.9; P=0.001).

CONCLUSIONS

The results of the present study indicated that individuals with MS who experience pain were significantly more likely to report a decreased employment rate than individuals with MS who were pain free.

Benign multiple sclerosis: does it exist?

Although the definition of benign multiple sclerosis (BMS) remains controversial, it is generally applied to a subgroup of MS patients showing little disease progression, with minimal disability decades after disease onset, and is based mainly on changes in motor function. Recent studies, however, reveal that deterioration of cognitive function, fatigue, pain, and depression also occur in BMS patients, causing negative impact on work and social activities, despite complete preservation of motor function. Using conventional MRI techniques, lesion load observed in BMS is similar to levels in other disease subtypes; however, newer quantitative MRI techniques show less tissue damage, as well as greater repair and compensatory efficiency following MS injury. Currently accepted criteria for BMS diagnosis may cause overestimation of true prevalence, underscoring the need for routine monitoring of nonmotor symptoms and imaging studies. Clearly, the definition of BMS currently applied in clinical practice requires reassessment.

Visual pathway axonal loss in benign multiple sclerosis: a longitudinal study

BACKGROUND

Benign multiple sclerosis (MS), traditionally defined as Expanded Disability Status Scale (EDSS) score ≤3 and ≥15-year disease duration, is thought to follow a milder clinical course. We determined the extent of visual pathway axonal loss by optical coherence tomography (OCT) retinal nerve fiber layer (RNFL) thickness in a benign MS cohort and examined the relation to vision and quality of life (QOL).

METHODS

In this longitudinal study of vision in MS at 3 academic centers, a subset of patients with EDSS, visual function, OCT, and QOL assessments was analyzed. Low- and high-contrast letter acuity was performed to assess visual function. RNFL thickness was determined using time-domain OCT. QOL scales included the 25-Item National Eye Institute Visual Functioning Questionnaire (NEI-VFQ-25) and Short Form-36 Health Survey.

RESULTS

Among 68 patients (135 eyes) studied longitudinally, 13 (26 eyes) had benign MS using criteria of EDSS score ≤3 and ≥15-year disease duration. Benign MS eyes had as much RNFL thinning (-3.6 μm, P = 0.0008 vs baseline, paired t test) as typical MS eyes (-3.3 μm, P < 0.0001). Both groups had significant low-contrast acuity loss. History of optic neuritis (ON) was more frequent in benign MS (69% vs 33% of eyes). History of ON distinguished benign vs typical MS (P = 0.002) and correlated with RNFL thickness at baseline (P = 0.002) and disease duration (P = 0.03) but not EDSS (P = 0.32, logistic regression). NEI-VFQ-25 scores were also worse for benign MS, accounting for age (75 ± 21 vs 88 ± 11, P = 0.005).

CONCLUSION

Patients with benign MS have RNFL axonal loss that is as marked as that of typical MS and have reduced vision and QOL. While overall neurologic impairment is mild, visual dysfunction, not well captured by the EDSS, accounts for a substantial degree of disability in benign MS.

'Clinically definite benign multiple sclerosis', an unwarranted conceptual hodgepodge: evidence from a 30-year observational study

BACKGROUND

Benign multiple sclerosis (BMS) is a controversial concept which is still debated. However identification of this kind of patients is crucial to prevent them from unnecessary exposure to aggressive and/or long term medical treatments.

OBJECTIVES

To assess two definitions of 'clinically definite benign multiple sclerosis' (CDBMS) using long-term follow-up data, and to look for prognostic factors of CDBMS.

METHODS

In 874 patients with definite relapsing-remitting MS, followed up for at least 10 years, disability was assessed using the Disability Status Scale (DSS). CDBMS was defined by either DSS score≤2 (CDBMS1 group) or DSS score≤ 3 (CDBMS2 group) at 10 years. We estimated the proportion of patients who were still benign at 20 and 30 years after clinical onset.

RESULTS

CDBMS frequency estimates were 57.7% and 73.9% when using CDBMS1 and CDBMS2 definitions, respectively. In the CDBMS1 group, only 41.7% (105/252) of cases were still benign 10 years later, and 41.1% (23/56) after an additional decade, while there were 53.8% (162/301) and 59.5% (44/74) respectively in the CDBMS2 group.

CONCLUSIONS

This 30-year observational study, which is one of the largest published series, indicates that favourable 10-year disability scores of DSS 2 or 3 fail to ensure a long-term benign course of multiple sclerosis. After every decade almost half of the CDBMS were no longer benign. CDBMS, as currently defined, is an unwarranted conceptual hodgepodge. Other criteria using new biomarkers (genetic, biologic or MRI) should be found to detect benign cases of MS.

Effect of vitamin D3 supplementation on relapses, disease progression, and measures of function in persons with multiple sclerosis: exploratory outcomes from a double-blind randomised controlled trial

BACKGROUND

High vitamin D levels may reduce the risk of relapses and disease progression in multiple sclerosis.

METHODS

This 96-week randomised controlled trial was designed to assess the effect of vitamin D(3) supplementation on bone mineral density in persons with multiple sclerosis. Supplementation with 20,000 IU vitamin D(3) weekly raised median serum 25-hydroxy vitamin D (25[OH]D) to 121 nmol/L. The modified intention to treat analysis included 35 persons in the vitamin D(3) group and 33 in the placebo group. Participants were age 21 to 50 years and fully ambulatory (median Expanded Disability Status Scale (EDSS) 2.5). We studied the effect of supplementing vitamin D(3) on the exploratory outcomes annualised relapse rate (ARR), EDSS, multiple sclerosis functional composite (MSFC) components, grip strength, and fatigue.

RESULTS

After 96 weeks, there was no significant difference between groups in ARR (absolute difference 0.10, 95% CI -0.07 to 0.27; p = 0.25), EDSS (absolute difference -0.01, 95% CI -0.35 to 0.35; p = 0.97), MSFC components, grip strength, or fatigue.

CONCLUSION

Supplementation with 20,000 IU vitamin D(3) weekly did not result in beneficial effects on the measured multiple sclerosis-related outcomes. This study was not powered to address clinical outcomes, but none of the results were suggestive of an effect in this unselected population of fully ambulatory persons with multiple sclerosis.

Benign multiple sclerosis: a new definition of this entity is needed

Background: To study a cohort of benign multiple sclerosis (BMS) patients beyond physical disability, including the evaluation of cognitive and social function, as well as fatigue, pain and MRI studies.

Methods: A cohort of 342 patients was prospectively followed for 10.9 ± 0.71 years. Forty-three patients (12.5%) met the BMS diagnosis criteria [Expanded Disability Status Scale (EDSS) < 3 after at least 10 years’ disease duration], undergoing full neurological examination every 6 months. Neuropsychological status, pain, fatigue, social functioning and work-related disability, as well as brain MRIs, were assessed yearly.

Results: By the end of follow-up, 20 of 43 BMS patients (47%) had suffered cognitive impairment and 23 (53.3%) referred depression. Furthermore, 21 (48.8%) reported significant changes in pain intensity, with fatigue and environmental severity scores significantly increasing over time in 33–35% of patients. Finally, 32 BMS patients (74%) showed significant increase in the number of new or enlarging T2 lesions, gadolinium-enhanced lesions, and persistent black holes, without changes in EDSS. Thirty-five of 43 patients (81%) fulfilling the BMS diagnostic criteria showed significant worsening of cognitive function, fatigue, pain or depression during the 10-year follow-up.

Conclusions: Currently accepted criteria for BMS diagnosis may cause overestimation of true prevalence, underscoring the need for routine monitoring of non-motor symptoms and imaging studies, to help physicians improve diagnostic accuracy as well as therapeutic decision-making in this subgroup of MS patients.

The neuropathological basis of clinical progression in multiple sclerosis

Multiple sclerosis is the major inflammatory condition affecting the central nervous system (CNS) and is characterised by disseminated focal immune-mediated demyelination. Demyelination is accompanied by variable axonal damage and loss and reactive gliosis. It is this pathology that is thought to be responsible for the clinical relapses that often respond well to immunomodulatory therapy. However, the later secondary progressive stage of MS remains largely refractory to treatment and it is widely suggested that accumulating axon loss is responsible for clinical progression. Although initially thought to be a white matter (WM) disease, it is increasingly apparent that extensive pathology is also seen in the grey matter (GM) throughout the CNS. GM pathology is characterised by demyelination in the relative absence of an immune cell infiltrate. Neuronal loss is also seen both in the GM lesions and in unaffected areas of the GM. The slow progressive nature of this later stage combined with the presence of extensive grey matter pathology has led to the suggestion that neurodegeneration might play an increasing role with increasing disease duration. However, there is a paucity of studies that have correlated the pathological features with clinical milestones during secondary progressive MS. Here, we review the contributions that the various types of pathology are likely to make to the increasing neurological deficit in MS.