"No association between disease modifying treatment and fatigue in multiple sclerosis".

BACKGROUND: Fatigue affects 60-90% of people with multiple sclerosis (MS). It reduces quality of life and the ability to work. The cause of fatigue in MS remains unknown. Several disease-modifying treatments (DMTs) slow the disease process in relapsing MS by suppressing neuroinflammation. We aimed to investigate if treatment with a DMT is associated with lower rates of fatigue. METHODS: In this cross-sectional study of the MS population in three counties in Norway, we used the Fatigue Scale for Motor and Cognitive Functions (FSMC) and the Hospital Anxiety and Depression Scale (HADS) to assess patient-reported fatigue, anxiety and depression. Clinical data were retrieved from the electronic patient record system. We categorized DMTs as high-efficacy therapy or moderate-efficacy therapy. High-efficacy drugs included fingolimod, natalizumab, ocrelizumab, rituximab, alemtuzumab, daclizumab, and autologous hematopoietic stem cell transplantation. Moderate-efficacy drugs included interferons, glatiramer acetate, dimethyl fumarate, and teriflunomide. We included persons with relapsing MS only. RESULTS: Of 1142 patients, 80% had fatigue. Fifty-six percent of the patients were on DMTs (25% on moderate-efficacy treatment and 30% on high-efficacy treatment), 18% had discontinued treatment and 26% had never received any DMT. Sex, level of disability as measured by the Multiple Sclerosis Severity Score, anxiety and depression were independently associated with fatigue. Moderate-efficacy treatment was associated with less fatigue, but not after adjustment for other variables. There was no association between high-efficacy treatment and fatigue. CONCLUSION: We found no independent relationship between the use of disease-modifying treatment and fatigue in MS.

The instrumented single leg stance test detects early balance impairment in people with multiple sclerosis.

Balance impairment is frequent in people with multiple sclerosis (pwMS) and affects risk of falls and quality of life. By using inertial measurement units (IMUs) on the Single Leg Stance Test (SLS) we aimed to discriminate healthy controls (HC) from pwMS and detect differences in balance endurance and quality. Thirdly, we wanted to test the correlation between instrumented SLS parameters and self-reported measures of gait and balance. Fifty-five pwMS with mild (EDSS<4) and moderate disability (EDSS≥4) and 20 HC performed the SLS with 3 IMUs placed on the feet and sacrum and filled the Twelve Item Multiple Sclerosis Walking Scale (MSWS-12) questionnaire. A linear mixed model was used to compare differences in the automated balance measures. Balance duration was significantly longer in HC compared to pwMS (p < 0.001) and between the two disability groups (p < 0.001). Instrumented measures identified that trunk stability (normalized mediolateral and antero-posterior center of mass stability) had the strongest association with disability (R2 marginal 0.30, p < 0.001) and correlated well with MSWS-12 (R = 0.650, p < 0.001). PwMS tended to overestimate own balance compared to measured balance duration. The use of both self-reported and objective assessments from IMUs can secure the follow-up of balance in pwMS.

Immune cell subpopulations and serum neurofilament light chain are associated with increased risk of disease worsening in multiple sclerosis.

Changes is lymphocyte subpopulations in peripheral blood have been proposed as biomarkers for evaluation of disease activity in multiple sclerosis (MS). Serum neurofilament light chain (sNfL) is a biomarker reflecting neuro-axonal injury in MS that could be used to monitor disease activity, response to drugs and to prognosticate disease course. Here we show a moderate correlation between sNfL and lymphocyte cell subpopulations, and our data furthermore suggest that sNfL and specific immune cell subpopulations together could predict future disease worsening in MS.

Rebaseline no evidence of disease activity (NEDA-3) as a predictor of long-term disease course in a Norwegian multiple sclerosis population.

Introduction: No evidence of disease activity with three components (NEDA-3) is achieved if the person with MS (pwMS) has no new MRI lesions, no new relapses and no change in Expanded disability status scale (EDSS) over 1 year. Whether NEDA-3 is a good tool in measuring disease activity is up for discussion, but it is superior to the individual parameters separately and user-friendly. There is disagreement on whether NEDA-3 is a good predictor of long-term disability. Methods: This is a retrospective cohort study using real-world data with limited selection bias from the complete MS population at two hospitals in the southeast of Norway. We included pwMS diagnosed between 2006 and 2017 who had enough information to determine time to failure of NEDA-3 after diagnosis. Results: Of 536 pwMS, only 38% achieved NEDA 1 year after diagnosis. PwMS achieving NEDA were more likely to be started on a high efficacy drug as the initial drug, but there were no demographic differences. Mean time to NEDA failure was 3.3 (95% CI 2.9-3.7) years. Starting a high efficiacy therapy was associated with an increased risk of sustaining NEDA as compared to those receiving moderate efficacy therapy. PwMS who achieved NEDA at year one had a mean time to EDSS 6 of 33.8 (95% CI 30.9-36.8) years vs. 30.8 (95% CI 25.0-36.6) years in pwMS who did not achieve NEDA, p < 0.001. When rebaselining NEDA 1 year after diagnosis, 52.2% achieved NEDA in the 1st year after rebaseline, mean time to NEDA failure was 3.4 (95% CI 3.0-3.7) years and mean time to EDSS 6 was 44.5 (95% CI 40.4-48.5) years in pwMS achieving NEDA vs. 29.6 (95% CI 24.2-35.0) years in pwMS not achieving NEDA, p < 0.001. After rebaseline, pwMS with a high efficacy therapy as the initial drug had a mean time from diagnosis to NEDA fail of 4.8 years (95% CI 3.9-5.8) vs. 3.1 years (95% CI 2.7-3.5) in pwMS started on a moderate efficacy therapy, p < 0.001. In pwMS with NEDA failure at year one, 70% failed one, 28% failed two and 2% failed three components. New MRI lesions were the most common cause of NEDA failure (63%), followed by new relapses (50%) and EDSS change (25%). Conclusion: NEDA-3 from rebaseline after 1 year, once treatment is stabilized, can predict the long-term disease course in MS. Starting a high efficacy DMT is associated with longer time to NEDA failure than moderate therapies. Finally, most pwMS only fail one component and new MRI lesions are the most likely cause of NEDA failure.

Serum neurofilament light chain concentration predicts disease worsening in multiple sclerosis.

BACKGROUND: Serum neurofilament light (sNfL) chain is a promising biomarker reflecting neuro-axonal injury in multiple sclerosis (MS). However, the ability of sNfL to predict outcomes in real-world MS cohorts requires further validation. OBJECTIVE: The aim of the study is to investigate the associations of sNfL concentration, magnetic resonance imaging (MRI) and retinal optical coherence tomography (OCT) markers with disease worsening in a longitudinal European multicentre MS cohort. METHODS: MS patients (n = 309) were prospectively enrolled at four centres and re-examined after 2 years (n = 226). NfL concentration was measured by single molecule array assay in serum. The patients' phenotypes were thoroughly characterized with clinical examination, retinal OCT and MRI brain scans. The primary outcome was disease worsening at median 2-year follow-up. RESULTS: Patients with high sNfL concentrations (⩾8 pg/mL) at baseline had increased risk of disease worsening at median 2-year follow-up (odds ratio (95% confidence interval) = 2.8 (1.5-5.3), p = 0.001). We found no significant associations of MRI or OCT measures at baseline with risk of disease worsening. CONCLUSION: Serum NfL concentration was the only factor associated with disease worsening, indicating that sNfL is a useful biomarker in MS that might be relevant in a clinical setting.

Exploring Retinal Blood Vessel Diameters as Biomarkers in Multiple Sclerosis.

We aimed to determine whether retinal vessel diameters and retinal oxygen saturation in newly diagnosed patients with multiple sclerosis (pwMS) are different from those of a healthy population. Retinal blood vessel diameters were measured using imaging with a spectrophotometric non-invasive retinal oximeter. Twenty-three newly diagnosed untreated relapsing-remitting MS (RRMS) patients (mean age: 32.2 ± 7.5 years, age range = 18-50 years, 56.5% female) were measured and compared to 23 age- and sex-matched healthy controls (HCs) (mean age: 34.8 ± 8.1 years). Patients with Optic Neuritis were excluded. Retinal venular diameter (143.8 µm versus 157.8 µm: mean; p = 0.0013) and retinal arteriolar diameter (112.6 µm versus 120.6 µm: mean; p = 0.0089) were smaller in pwMS when compared with HCs, respectively. There was no significant difference in the oxygen saturation in retinal venules and arterioles in pwMS (mean: 60.0% and 93.7%; p = 0.5980) compared to HCs (mean: 59.3% and 91.5%; p = 0.8934), respectively. There was a significant difference in the median low contrast visual acuity (2.5% contrast) between the pwMS and the HC groups (p = 0.0143) Retinal arteriolar and venular diameter may have potential as objective biomarkers for MS.

Fatigue in multiple sclerosis is associated with socioeconomic factors.

OBJECTIVES: Fatigue is one of the leading causes of reduced quality of life and inability to work in people with multiple sclerosis (pwMS). Currently, no treatment effectively ameliorates fatigue. We still know little about what causes fatigue and which factors may contribute to fatigue. Knowledge about socioeconomic factors' role in fatigue might help us recognize strategies for the management of fatigue. Our aim was to explore whether socioeconomic factors are associated with the presence or level of perceived fatigue. METHODS: This is a cross-sectional study of the MS population in three Norwegian counties. We used the Fatigue Scale for Motor and Cognitive Functions to assess self-reported fatigue, and obtained socioeconomic data from Statistics Norway and questionnaires. To assess self-reported anxiety and depression, we employed the Hospital Anxiety and Depression Scale. Clinical data were gathered from the hospital record system. RESULTS: The response rate was 64% (1599/2512). Seventy percent of the respondents were female, and the mean age was 52 years. Higher levels of education were associated with lower levels of fatigue. Receiving a disability pension, being divorced and having children were all factors associated with higher levels of fatigue, as were low parental education, low income, current smoking, and autoimmune comorbidities. We found a higher prevalence of anxiety and depression in pwMS with fatigue compared to those without fatigue CONCLUSION: Female sex, high level of disability, anxiety, depression and socioeconomic factors were independently associated with fatigue in contemporary patients with MS. These factors should be considered when devising management strategies.

The influence of socioeconomic factors on access to disease modifying treatment in a Norwegian multiple sclerosis cohort.

OBJECTIVE: Several studies report an impact of socioeconomic factors on access to disease modifying treatment (DMT) in multiple sclerosis (MS), with a trend of less access to more deprived persons. We investigated the impact of socioeconomic status (SES) on access to treatment in a well-defined Norwegian MS cohort. METHODS: This is a study of a population-based Norwegian MS cohort. We collected detailed information on disease development, progression, and DMT administered. Socioeconomic data was obtained from Statistics Norway and a questionnaire. RESULTS: We included 1314 persons with relapsing remitting MS at the prevalence date 01/01/2018. The population ever treated with DMTs is younger at onset, has shorter time from onset to diagnosis and lower expanded disability status score (EDSS) at diagnosis. The persons with MS (pwMS) with the highest levels of education, and those who are married are more likely to be ever treated with DMT. In the subgroup treated with a high efficacy DMT as a first drug, the pwMS are younger at prevalence date (39.9 years (SD 12.1)) compared with those who are not treated with a high efficacy DMT as first drug (43.8 years (SD 10.3)). The subgroup treated with a high efficacy DMT as a first drug has a 0.5 point higher EDSS at diagnosis compared to those not treated with a high efficacy DMT as a first drug. The level of education, household income and marital status are inversely related to access to high efficacy DMT as a first drug. None of the above differences persist when analyzing the subgroup diagnosed within the last six years (2012-2017). CONCLUSIONS: Since 2012, the pwMS in this Norwegian cohort are treated equally with DMT in terms of different measures of socioeconomic position.

Sensor-based gait analyses of the six-minute walk test identify qualitative improvement in gait parameters of people with multiple sclerosis after rehabilitation.

The aim of this work was to determine whether wearable inertial measurement units (IMUs) could detect gait improvements across different disability groups of people with Multiple Sclerosis (pwMS) by the six-minute walk test (6MWT) during a rehabilitation stay in a specialized rehabilitation center. Forty-six pwMS and 20 healthy controls (HC) were included in the study. They performed the 6MWT with two inertial measurement units (IMUs) placed on the feet. Thirty-two of the pwMS were retested at the end of the stay. PwMS were divided in a mild-disability and a moderate-disability group. The 6MWT was divided in six sections of 1 min each for technical analysis, and linear mixed models were used for statistical analyses. The comparison between the two disability groups and HC highlighted significant differences for each gait parameter (all p < 0.001). The crossing effect between the test-retest and the two disability groups showed greater improvement for the moderate-disability group. Finally, the gait parameter with the higher effect size, allowing the best differentiation between the disability groups, was the foot flat ratio (R2 = 0.53). Gait analyses from wearable sensors identified different evolutions of gait patterns during the 6MWT in pwMS with different physical disability. The measured effect of a short-time rehabilitation on gait with 6MWT was higher for pwMS with higher degree of disability. Using IMUs in a clinical setting allowed to identify significant changes in inter-stride gait patterns. Wearable sensors and key parameters have the potential as useful clinical tools for focusing on gait in pwMS.

Stereotyped B-cell responses are linked to IgG constant region polymorphisms in multiple sclerosis.

Clonally related B cells infiltrate the brain, meninges, and cerebrospinal fluid of MS patients, but the mechanisms driving the B-cell response and shaping the immunoglobulin repertoires remain unclear. Here, we used single-cell full-length RNA-seq and BCR reconstruction to simultaneously assess the phenotypes, isotypes, constant region polymorphisms, and the paired heavy- and light-chain repertoires in intrathecal B cells. We detected extensive clonal connections between the memory B cell and antibody-secreting cell (ASC) compartments and observed clonally related cells of different isotypes including IgM/IgG1, IgG1/IgA1, IgG1/IgG2, and IgM/IgA1. There was a strong dominance of the G1m1 allotype constant region polymorphisms in ASCs, but not in memory B cells. Tightly linked to the G1m1 allotype, we found a preferential pairing of the immunoglobulin heavy-chain variable (IGHV)4 gene family with the κ variable (IGKV)1 gene family. The IGHV4-39 gene was most used and showed the highest frequency of pairing with IGKV1-5 and IGKV1(D)-33. These results link IgG constant region polymorphisms to stereotyped B-cell responses in MS and indicate that the intrathecal B-cell response in these patients could be directed against structurally similar epitopes.

No significant differences in absenteeism or academic achievements in a Norwegian multiple sclerosis case control study.

BACKGROUND: The duration and features of the multiple sclerosis (MS) prodrome are not well defined. We aimed to ascertain whether people with a future MS diagnosis have more days of absence and perform worse in upper secondary school than age, gender and county-matched controls. METHODS: Using registry data from the southeast of Norway, we identified people with MS born ≥1978. Statistics Norway provided information on grades and days of absence in cases and matched controls. We looked at absence in the three years of upper secondary school and grades in the compulsory subjects Norwegian, English, mathematics and physical education. RESULTS: We identified 107 cases with disease onset one year or more after graduation and 626 controls. There were no significant differences in absence or grades achieved in the population as a whole or in those with disease onset within four years of diagnosis, and no association between time to disease onset and days of absence or grades. CONCLUSION: There was no difference in days of absence or grades achieved in upper secondary school in the four years leading up to disease onset in cases compared to controls. A potential prodrome may not affect cognition enough to impact school achievements.

Early High Efficacy Treatment in Multiple Sclerosis Is the Best Predictor of Future Disease Activity Over 1 and 2 Years in a Norwegian Population-Based Registry.

Background: Moderate and high efficacy disease modifying therapies (DMTs) have a profound effect on disease activity. The current treatment guidelines only recommend high efficacy DMTs for patients with highly active MS. The objective was to examine the impact of initial treatment choice in achieving no evidence of disease activity (NEDA) at year 1 and 2. Methods: Using a real-world population-based registry with limited selection bias from the southeast of Norway, we determined how many patients achieved NEDA on moderate and high efficacy DMTs. Results: 68.0% of patients who started a high efficacy DMT as the first drug achieved NEDA at year 1 and 52.4% at year 2 as compared to 36.0 and 19.4% of patients who started a moderate efficacy DMT as a first drug. The odds ratio (OR) of achieving NEDA on high efficacy drugs compared to moderate efficacy drugs as a first drug at year 1 was 3.9 (95% CI 2.4-6.1, p < 0.001). The OR for high efficacy DMT as the second drug was 2.5 (95% CI 1.7-3.9, p < 0.001), and was not significant for the third drug. Patients with a medium or high risk of disease activity were significantly more likely to achieve NEDA on a high efficacy therapy as a first drug compared to moderate efficacy therapy as a first drug. Conclusions: Achieving NEDA at year 1 and 2 is significantly more likely in patients on high-efficacy disease modifying therapies than on moderate efficacy therapies, and the first choice of treatment is the most important. The immunomodulatory treatment guidelines should be updated to ensure early, high efficacy therapy for the majority of patients diagnosed with MS.

Maternal education has significant influence on progression in multiple sclerosis.

OBJECTIVE: The identification of potential risk factors for disease severity is of great importance in the treatment of multiple sclerosis. The influence of socioeconomic status on progression in multiple sclerosis (MS) is sparsely investigated. Our aim was to investigate how socioeconomic status in adolescence influences disease progression in later life. METHODS: A total of 1598 patients with multiple sclerosis from a well-defined population in Norway were included. Detailed information on disease progression, measured by expanded disability status scale (EDSS) and multiple sclerosis severity score (MSSS), were combined with data on socioeconomic factors. We used residency and parental level of education at patients' age 16 and exposure to second-hand smoking as a measure of socioeconomic status in adolescence, adjusting for the same variables as well as use of disease modifying treatments at prevalence date 01.01.18. RESULTS: High maternal level of education at patients' age 16 was significantly associated with less pronounced disease progression measured by MSSS (ß-coefficient -0.58, p = 0.015), younger age and lower EDSS at disease onset, and shorter time from onset to diagnosis. No significant associations were found for paternal education level and MSSS. The use of any disease modifying treatment before prevalence date was significantly associated with disease progression (ß-coefficient -0.49, p=0.004), while residence, current and second-hand smoking were not. CONCLUSION: This study on a population-based, real-world cohort shows that the parental level of education has a significant impact on a timely diagnosis of MS. In addition to disease modifying treatment, maternal level of education also had an impact on disease progression in later life.

High prevalence of fatigue in contemporary patients with multiple sclerosis.

OBJECTIVE: The prevalence of multiple sclerosis (MS)-related fatigue may have changed due to new diagnostic criteria and new disease modifying drugs. We aimed to assess the prevalence of fatigue in a contemporary MS cohort, and to explore associations between fatigue and clinical and demographic factors. METHODS: This is a cross-sectional study of the MS population in three Norwegian counties. Fatigue was assessed with the Fatigue Scale for Motor and Cognitive Functions (FSMC). We also assessed self-reported anxiety, depression and daytime sleepiness. RESULTS: The response rate was 64% (1599/2512). The mean age of the participants was 52 ± 13 years, median EDSS was 2.5 (IQR 1.5-3.0) and median disease duration from onset was 16 years (IQR 8-25). We found a prevalence of fatigue of 81%. Women had a higher prevalence of fatigue than men (83% vs 78%, p = 0.02). The prevalence increased with age (p < 0.001) and with increasing disease severity (p < 0.001), but in multivariate analyses, only sex and disease severity remained independent determinants of fatigue. Anxiety, depression, and daytime sleepiness were more prevalent in patients with fatigue than in those without fatigue (all p-values < 0.001). CONCLUSION: The prevalence of fatigue is high in contemporary patients with MS. Fatigue is associated with female sex and level of disability, as well as with anxiety, depression and excessive daytime sleepiness.

The course of multiple sclerosis rewritten: a Norwegian population-based study on disease demographics and progression.

OBJECTIVES: Over the past few decades, there has been an improvement in the rate of disability progression in multiple sclerosis (MS) patients, and most studies relate this evolvement to the introduction of disease-modifying therapies. However, several other factors have changed over this period, including access to MRI and newer diagnostic criteria. The aim of this study is to investigate changes in the natural course of MS over time in a near-complete and geographically well-defined population from the south-east of Norway. METHODS: We examined disease progression and demographics over two decades and assessed the effect of disease-modifying therapies using linear mixed-effect models. RESULTS: In a cohort of 2097 patients, we found a significant improvement in disability as measured by the Expanded Disability Status Scale (EDSS) stratified by age, and the improvement remained significant after adjusting for time on disease-modifying medications, gender and progressive MS at onset. The time from disease onset to EDSS 6 in the total cohort was 29.8 years (95% CI 28.5-31.1) and was significantly longer in patients diagnosed after 2006 compared to patients diagnosed before. There are significant differences between patient demographics, as well as time to EDSS 6, in the near-complete, geographically well-defined population compared to an additional cohort from the capital Oslo and its suburbs. CONCLUSION: The natural course of MS is improving, but the improvement seen in disease progression has multifaceted explanations. Our study underlines the importance of completeness of data, relevant timeframes and demographics when comparing different MS populations. Studies on incomplete populations should be interpreted with caution.

LesionQuant for Assessment of MRI in Multiple Sclerosis-A Promising Supplement to the Visual Scan Inspection.

Background and Goals: Multiple sclerosis (MS) is a central nervous system inflammatory disease where magnetic resonance imaging (MRI) is an important tool for diagnosis and disease monitoring. Quantitative measurements of lesion volume, lesion count, distribution of lesions, and brain atrophy have a potentially significant value for evaluating disease progression. We hypothesize that utilizing software designed for evaluating MRI data in MS will provide more accurate and detailed analyses compared to the visual neuro-radiological evaluation. Methods: A group of 56 MS patients (mean age 35 years, 70% females and 96% relapsing-remitting MS) was examined with brain MRI one and 5 years after diagnosis. The T1 and FLAIR brain MRI sequences for all patients were analyzed using the LesionQuant (LQ) software. These data were compared with data from structured visual evaluations of the MRI scans performed by neuro-radiologists, including assessments of atrophy, and lesion count. The data from LQ were also compared with data from other validated research methods for brain segmentation, including assessments of whole brain volume and lesion volume. Correlations with clinical tests like the timed 25-foot walk test (T25FT) were performed to explore additional value of LQ analyses. Results: Lesion count assessments by LQ and by the neuro-radiologist were significantly correlated one year (cor = 0.92, p = 2.2 × 10-16) and 5 years (cor = 0.84, p = 2.7 × 10-16) after diagnosis. Analyzes of the intra- and interrater variability also correlated significantly (cor = 0.96, p < 0.001, cor = 0.97, p < 0.001). Significant positive correlation was found between lesion volume measured by LQ and by the software Cascade (cor = 0.7, p < 0.001. LQ detected a reduction in whole brain percentile >10 in 10 patients across the time-points, whereas the neuro-radiologist assessment identified six of these. The neuro-radiologist additionally identified five patients with increased atrophy in the follow-up period, all of them displayed decreasing low whole brain percentiles (median 11, range 8-28) in the LQ analysis. Significant positive correlation was identified between lesion volume measured by LQ and test performance on the T25FT both at 1 and 5 years after diagnosis. Conclusion: For the number of MS lesions at both time-points, we demonstrated strong correlations between the assessments done by LQ and the neuro-radiologist. Lesion volume evaluated with LQ correlated with T25FT performance. LQ-analyses classified more patients to have brain atrophy than the visual neuro-radiological evaluation. In conclusion, LQ seems like a promising supplement to the evaluation performed by neuro-radiologists, providing an automated tool for evaluating lesions in MS patients and also detecting early signs of atrophy in both a longitudinal and cross-sectional setting.

Prevalence of multiple sclerosis in rural and urban districts in Telemark county, Norway.

OBJECTIVE: To explore the trends in prevalence and incidence of multiple sclerosis (MS) in Telemark, Norway (latitude 58.7-60.3˚N), over the past two decades, with focus on differences between rural and urban areas. METHODS: Data from all patients with a confirmed diagnosis of MS in Telemark since 1993 were prospectively recorded and collected in a retrospective chart review. Prevalence estimates on January 1st 1999, 2009 and 2019, and incidence rates at five-year intervals between 1999 and 2018 were calculated and all results were adjusted to the European Standard Population. The study population was divided into urban and rural residency using a Norwegian governmental index. RESULTS: We registered 579 patients with MS in Telemark between 1999 and 2019. The adjusted prevalence estimates for January 1st 1999, 2009 and 2019 were 105.8/105, 177.1/105 and 260.6/105, respectively. In 2019, the prevalence estimates were 250.4/105 in urban and 316.2 /105 in rural areas. Between 1999 and 2018, the yearly incidence increased from 8.4/105 to 14.4/105. CONCLUSIONS: The prevalence of MS in Telemark is among the highest ever reported in Norway, consistent with an increasing incidence in the county over the past twenty years. The even higher prevalence in the rural areas is unlikely to be explained by possible risk factors like latitude, exposure to sunlight and diet. Further studies on differences between urban and rural areas are required to reveal possible new risk factors.

The diagnostic value of IgG index versus oligoclonal bands in cerebrospinal fluid of patients with multiple sclerosis.

BACKGROUND: Diagnostic criteria for multiple sclerosis have been developed to guide the diagnostic process. In the latest revision of the McDonald criteria, the presence of oligoclonal bands may replace the need for dissemination in time. The aim of this study is to investigate if the less time-consuming analysis of immunoglobulin G index in cerebrospinal fluid can safely predict the findings of oligoclonal bands. METHODS: This is a retrospective study of patients with multiple sclerosis at three hospitals in South-East Norway where lumbar puncture is performed routinely. We included patients diagnosed with multiple sclerosis after 2005 with known oligoclonal band status and an immunoglobulin G index score. RESULTS: Of 1295 patients diagnosed during or after 2005, 93.8% were oligoclonal band positive at diagnosis. Of 842 multiple sclerosis patients with known immunoglobulin G index and oligoclonal band status, 93.3% were oligoclonal band positive and 76.7% had an elevated immunoglobulin G index. The positive predictive value of a high immunoglobulin G index when oligoclonal bands are positive was 99.4% (95% confidence interval 98.4-99.8%). The negative predictive value of a normal immunoglobulin G index when oligoclonal bands are negative was 26.5% (95% confidence interval 23.5-29.9%). CONCLUSION: An immunoglobulin G index >0.7 has a positive predictive value >99% for oligoclonal bands. An elevated immunoglobulin G index adds diagnostic value versus oligoclonal bands and saves time in the diagnostic process.

Hospitalization following influenza infection and pandemic vaccination in multiple sclerosis patients: a nationwide population-based registry study from Norway.

Patients with multiple sclerosis (MS) are at increased risk of infections and related worsening of neurological function. Influenza infection has been associated with increased risk of various neurological complications. We conducted a population-based registry study to investigate the risk of acute hospitalization of MS patients in relation to influenza infection or pandemic vaccination in Norway. The entire Norwegian population in the years 2008-2014 was defined as our study population (N = 5,219,296). Information on MS diagnosis, influenza infection and vaccination were provided by Norwegian national registries. The self-controlled case series method was used to estimate incidence rate ratios (IRRs) with 95% confidence intervals (95% CI) in defined risk periods. 6755 MS patients were identified during the study period. Average age at first registration of an MS diagnosis was 51.8 years among men and 49.9 years among females (66.9%). The IRR for emergency hospitalization among MS patients the first week after an influenza diagnosis was 3.4 (95% CI 2.4-4.8). The IRR was 5.6 (95% CI 2.7-11.3) after pandemic influenza, and 4.8 (95% CI 3.1-7.4) after seasonal influenza. Pandemic vaccination did not influence risk of hospitalization [IRR within the first week: 0.7 (95% CI 0.5-1.0)]. Among MS patients, influenza infection was associated with increased risk for acute hospitalization while no increased risk was observed after pandemic vaccination. Influenza vaccination could prevent worsening of MS-related symptoms as well as risk of hospitalization.

No differential gene expression for CD4+ T cells of MS patients and healthy controls.

BACKGROUND: Multiple sclerosis-associated genetic variants indicate that the adaptive immune system plays an important role in the risk of developing multiple sclerosis. It is currently not well understood how these multiple sclerosis-associated genetic variants contribute to multiple sclerosis risk. CD4+ T cells are suggested to be involved in multiple sclerosis disease processes. OBJECTIVE: We aim to identify CD4+ T cell differential gene expression between multiple sclerosis patients and healthy controls in order to understand better the role of these cells in multiple sclerosis. METHODS: We applied RNA sequencing on CD4+ T cells from multiple sclerosis patients and healthy controls. RESULTS: We did not identify significantly differentially expressed genes in CD4+ T cells from multiple sclerosis patients. Furthermore, pathway analyses did not identify enrichment for specific pathways in multiple sclerosis. When we investigated genes near multiple sclerosis-associated genetic variants, we did not observe significant enrichment of differentially expressed genes. CONCLUSION: We conclude that CD4+ T cells from multiple sclerosis patients do not show significant differential gene expression. Therefore, gene expression studies of all circulating CD4+ T cells may not result in viable biomarkers. Gene expression studies of more specific subsets of CD4+ T cells remain justified to understand better which CD4+ T cell subsets contribute to multiple sclerosis pathology.