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Background: The use of disease-modifying therapies (DMTs) in multiple sclerosis (MS) has been associated with reduced relapse rates and accumulation of disability. However, studies examining impact of DMT on risk of transition to secondary progressive MS (SPMS) leveraging population-based nationwide data are still rare. Here, we determine the population incidence of conversion to SPMS using two consecutive nation-wide cohorts, one immediately before and one after the introduction of DMT in Sweden., Methods: We included two consecutive population cohorts of relapsing-remitting MS (RRMS) from the Swedish national MS register for the periods 1975-1994 (n = 2161), before DMT availability, and 1995-2011 (n = 3510), in which DMTs, mainly first generation DMT (injectables), became available and eventually were used by 70% of patients. We explored the risk of transition to SPMS as a calendar year function encompassing the two cohorts. In addition, we determined the incidence of transition to SPMS through age strata below and above 50 years in untreated and treated patient subgroups., Results: The risk of conversion to SPMS (adjusted for current age, current time since onset, calendar year and sex) was significantly lower in the second compared with the first population cohort (hazard ratio 0.58; CI 0.48, 0.70). The risk of SPMS conversion per calendar year decreased by 2.6% annually (p < 0.001) after 1995. The risk of SPMS conversion increased with age until age 50. Thereafter, it was unchanged or decreased among those with early MS onset age (<35 years), but continued to increase with onset at higher age, with similar trends in treated and untreated subgroups., Conclusion: The incidence of SPMS conversion significantly decreased at the population level after introduction of first generation DMTs by 1995. DMT efficiency was confirmed by a downward turn of the annual trajectory of the risk of SPMS conversion after 1995. An onset age determined pattern of variable SPMS incidence in higher age appeared in both treated and untreated strata. While first generation DMT delayed conversion to SPMS, their long-term effect was only moderate., Competing Interests: Declaration of Competing Interest Helen Tedeholm received a research grant from the Swedish MS Society in 2018. Funds for research time were granted by the Western Swedish Region. Fredrik Piehl has received research grants from Genzyme, Merck KGaA, and UCB, and fees for serving as chair of DMC in clinical trials with Parexel. Jan Lycke has received travel support and/or lecture honoraria from Biogen, Novartis, Merck, Alexion, Roche, and SanofiGenzyme; has served on scientific advisory boards for Biogen, Novartis, Merck, Roche, BSM, and SanofiGenzyme; serves on the editorial board of Acta Neurologica Scandinavica; and has received unconditional research grants from Biogen and Novartis. Jenny Link has nothing to declare. Leszek Stawiarz has nothing to declare. Joachim Burman has nothing to declare. Pierre de Flon has nothing to declare. Katarina Fink has received honoraria for lectures and advisory boards from Merck, Novartis, Roche, Biogen, and Aktelion. Martin Gunnarsson has nothing to declare. Johan Mellergård has received honoraria for advisory boards from Biogen, Sanofi Genzyme and Merck and lecture honoraria from Merck. Petra Nilsson has received travel support from Bayer Schering Pharma, Merck Serono, Biogen, and Genzyme a Sanofi Company; honoraria for lectures and advisory boards from Merck Serono and Genzyme a Sanofi Company; serves on advisory boards for Novartis and Roche; lectures for Biogen; and has received unrestricted grants from Biogen. Peter Sundström has nothing to declare. Anders Svenningsson has nothing to declare. Helena Johansson has nothing to declare. Oluf Andersen serves on the editorial board of Acta Neurologica Scandinavica., (Copyright © 2022. Published by Elsevier B.V.)

Despite important efforts to solve the clinico-radiological paradox, correlation between lesion load and physical disability in patients with multiple sclerosis remains modest. One hypothesis could be that lesion location in corticospinal tracts plays a key role in explaining motor impairment. In this study, we describe the distribution of lesions along the corticospinal tracts from the cortex to the cervical spinal cord in patients with various disease phenotypes and disability status. We also assess the link between lesion load and location within corticospinal tracts, and disability at baseline and 2-year follow-up. We retrospectively included 290 patients (22 clinically isolated syndrome, 198 relapsing remitting, 39 secondary progressive, 31 primary progressive multiple sclerosis) from eight sites. Lesions were segmented on both brain (T2-FLAIR or T2-weighted) and cervical (axial T2- or T2*-weighted) MRI scans. Data were processed using an automated and publicly available pipeline. Brain, brainstem and spinal cord portions of the corticospinal tracts were identified using probabilistic atlases to measure the lesion volume fraction. Lesion frequency maps were produced for each phenotype and disability scores assessed with Expanded Disability Status Scale score and pyramidal functional system score. Results show that lesions were not homogeneously distributed along the corticospinal tracts, with the highest lesion frequency in the corona radiata and between C2 and C4 vertebral levels. The lesion volume fraction in the corticospinal tracts was higher in secondary and primary progressive patients (mean = 3.6 ± 2.7% and 2.9 ± 2.4%), compared to relapsing-remitting patients (1.6 ± 2.1%, both P < 0.0001). Voxel-wise analyses confirmed that lesion frequency was higher in progressive compared to relapsing-remitting patients, with significant bilateral clusters in the spinal cord corticospinal tracts (P < 0.01). The baseline Expanded Disability Status Scale score was associated with lesion volume fraction within the brain (r = 0.31, P < 0.0001), brainstem (r = 0.45, P < 0.0001) and spinal cord (r = 0.57, P < 0.0001) corticospinal tracts. The spinal cord corticospinal tracts lesion volume fraction remained the strongest factor in the multiple linear regression model, independently from cord atrophy. Baseline spinal cord corticospinal tracts lesion volume fraction was also associated with disability progression at 2-year follow-up (P = 0.003). Our results suggest a cumulative effect of lesions within the corticospinal tracts along the brain, brainstem and spinal cord portions to explain physical disability in multiple sclerosis patients, with a predominant impact of intramedullary lesions., (© The Author(s) (2020). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Spinal cord lesions detected on MRI hold important diagnostic and prognostic value for multiple sclerosis. Previous attempts to correlate lesion burden with clinical status have had limited success, however, suggesting that lesion location may be a contributor. Our aim was to explore the spatial distribution of multiple sclerosis lesions in the cervical spinal cord, with respect to clinical status. We included 642 suspected or confirmed multiple sclerosis patients (31 clinically isolated syndrome, and 416 relapsing-remitting, 84 secondary progressive, and 73 primary progressive multiple sclerosis) from 13 clinical sites. Cervical spine lesions were manually delineated on T2- and T2*-weighted axial and sagittal MRI scans acquired at 3 or 7 T. With an automatic publicly-available analysis pipeline we produced voxelwise lesion frequency maps to identify predilection sites in various patient groups characterized by clinical subtype, Expanded Disability Status Scale score and disease duration. We also measured absolute and normalized lesion volumes in several regions of interest using an atlas-based approach, and evaluated differences within and between groups. The lateral funiculi were more frequently affected by lesions in progressive subtypes than in relapsing in voxelwise analysis (P < 0.001), which was further confirmed by absolute and normalized lesion volumes (P < 0.01). The central cord area was more often affected by lesions in primary progressive than relapse-remitting patients (P < 0.001). Between white and grey matter, the absolute lesion volume in the white matter was greater than in the grey matter in all phenotypes (P < 0.001); however when normalizing by each region, normalized lesion volumes were comparable between white and grey matter in primary progressive patients. Lesions appearing in the lateral funiculi and central cord area were significantly correlated with Expanded Disability Status Scale score (P < 0.001). High lesion frequencies were observed in patients with a more aggressive disease course, rather than long disease duration. Lesions located in the lateral funiculi and central cord area of the cervical spine may influence clinical status in multiple sclerosis. This work shows the added value of cervical spine lesions, and provides an avenue for evaluating the distribution of spinal cord lesions in various patient groups., (© The Author(s) (2019). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

The spinal cord is frequently affected by atrophy and/or lesions in multiple sclerosis (MS) patients. Segmentation of the spinal cord and lesions from MRI data provides measures of damage, which are key criteria for the diagnosis, prognosis, and longitudinal monitoring in MS. Automating this operation eliminates inter-rater variability and increases the efficiency of large-throughput analysis pipelines. Robust and reliable segmentation across multi-site spinal cord data is challenging because of the large variability related to acquisition parameters and image artifacts. In particular, a precise delineation of lesions is hindered by a broad heterogeneity of lesion contrast, size, location, and shape. The goal of this study was to develop a fully-automatic framework - robust to variability in both image parameters and clinical condition - for segmentation of the spinal cord and intramedullary MS lesions from conventional MRI data of MS and non-MS cases. Scans of 1042 subjects (459 healthy controls, 471 MS patients, and 112 with other spinal pathologies) were included in this multi-site study (n = 30). Data spanned three contrasts (T 1 -, T 2 -, and T 2 ∗ -weighted) for a total of 1943 vol and featured large heterogeneity in terms of resolution, orientation, coverage, and clinical conditions. The proposed cord and lesion automatic segmentation approach is based on a sequence of two Convolutional Neural Networks (CNNs). To deal with the very small proportion of spinal cord and/or lesion voxels compared to the rest of the volume, a first CNN with 2D dilated convolutions detects the spinal cord centerline, followed by a second CNN with 3D convolutions that segments the spinal cord and/or lesions. CNNs were trained independently with the Dice loss. When compared against manual segmentation, our CNN-based approach showed a median Dice of 95% vs. 88% for PropSeg (p ≤ 0.05), a state-of-the-art spinal cord segmentation method. Regarding lesion segmentation on MS data, our framework provided a Dice of 60%, a relative volume difference of -15%, and a lesion-wise detection sensitivity and precision of 83% and 77%, respectively. In this study, we introduce a robust method to segment the spinal cord and intramedullary MS lesions on a variety of MRI contrasts. The proposed framework is open-source and readily available in the Spinal Cord Toolbox., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Objectives: The aim of this study was to identify factors influencing the long-term clinical progression of multiple sclerosis (MS). A special objective was to investigate whether early treatment decisions influence outcome., Methods: We included 639 patients diagnosed with MS from 2001 to 2007. The median follow-up time was 99 months (8.25 years). Cox regression models were applied to identify factors correlating with the outcome variable defined as time from treatment start to irreversible score 4 of the Expanded Disability Status Scale (EDSS)., Results: Patients initiated on treatment later had a greater risk of reaching EDSS 4 (hazard ratio of 1.074 (95% confidence interval (CI), 1.048-1.101)), increased by 7.4% for every year of delay in treatment start after MS onset. Patients who started treatment after 3 years from MS onset reached the outcome sooner with hazard ratio of 2.64 (95% CI, 1.71-4.08) compared with the patients who started treatment within 1 year from MS onset. Baseline EDSS and age at onset were found to be predictive factors of disability progression., Conclusion: Early treatment initiation was associated with a better clinical outcome. In addition, we confirmed the well-established prognostic factors of late age at onset and early disability.

Background: Multiple sclerosis (MS) is a chronic disease of the central nervous system. One of the major questions concerning the clinical progression of MS, still insufficiently elaborated or confirmed, is if it can be slowed down or augmented by external factors. Immunomodulatory treatment is a disease modifiable factor shown to influence disease progression of various medical conditions., Objective: To investigate if treatment affects the long-term clinical progression of MS, measured as time from diagnosis to score of 4 or higher of Expanded Disability Status Scale (EDSS)., Methods: Longitudinal, prospective data concerning treatment status and EDSS were collected by health professionals in the Swedish MS Registry. Study cohort comprised new diagnosed MS patients at Karolinska Hospital between 2001 and 2005. Survival analysis adjusted for suspected confounders was used with the outcome variable time from diagnosis to EDSS ≥ 4., Results: Early treatment was correlated with longer time from diagnosis to EDSS ≥ 4 (HR: 1.77; 95 % CI: 1.15-2.73; p = 0.01). Additionally, the influence of the covariates-age at onset and the baseline EDSS, which were statistically significant with hazard ratios of 1.03 and 2.1, respectively, was found., Conclusion: Early treatment was associated with a better clinical outcome.

The Swedish MS registry (SMSreg) is designed to assure quality health care for patients with multiple sclerosis (MS). It has been active since 2001 and web-based since 2004. It runs on government funding only and is used in all Swedish neurology departments. The SMSreg currently includes data on 14,500 of Sweden's estimated 17,500 prevalent patients with MS. One important function of SMSreg, to which participation is voluntary, is to serve as a tool for decision support and to provide an easy overview of the patient information needed at clinical visits. This is its core feature and explains why the majority of Swedish MS specialists contribute data. Another success factor for SMSreg is that entered data can be readily accessed, either through a query function into Excel format or through a set of predesigned tables and diagrams in which parameters can be selected. Recent development includes a portal allowing patients to view a summary of their registered data and to report a set of patient-reported outcomes. SMSreg data have been used in close to 100 published scientific reports. Current projects include an incidence cohort (EIMS), post-marketing cohorts of patients on novel disease-modifying drugs (IMSE), and a prevalence cohort (GEMS). As these studies combine physical sampling and questionnaire data with clinical documentation and possible linkage to other public registries, together they provide an excellent platform for integrated MS research., (© 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Background: An increasing women-to-men ratio in later birth cohorts of patients with multiple sclerosis (MS) has been observed in several populations and has been hypothesised to be due to one or several environmental factors of importance for disease aetiology. However, in a study based on data from the Swedish MS registry (SMSreg) this ratio was recently reported to be rather stable during the 20(th) century., Objective: The purpose of this study was to reinvestigate the women-to-men ratio in Sweden based on data from all available data sources, including deceased patients., Method: We combined data from the SMSreg with data from national patient registers., Results: In total we obtained information on 19,510 MS patients born 1931-1985, 13,321 women and 6189 men. The women-to-men ratio increased from 1.70 for patients born in the 1930s to 2.67 for patients born in the 1980s. When comparing the coverage of SMSreg to the full data set, a significantly higher proportion of women born 1931-1935 compared to men born in the same period were found in SMSreg, resulting in a sampling bias hiding the increasing sex ratio in the full material., Conclusion: The women-to-men ratio in MS has increased in Sweden during the 20(th) century similarly to observations in other western countries., (© The Author(s), 2014.)

Background: Long-term changes regarding corpus callosum area (CCA) and information processing speed in cognitive and sensory-motor tasks have rarely been studied in multiple sclerosis (MS)., Objective and Methods: Information processing speed in cognitive (Symbol Digit Modalities Test, SDMT), sensory (visual and auditory reaction time) and motor (finger-tapping speed, FT; right and left hand) tasks as well as auditory inter-hemispheric transfer (verbal dichotic listening, VDL) was related to CCA, measured by MRI at baseline and at follow-up after nine years in 22 patients with MS. Possible confounding by demographic (age, gender and education), clinical (symptom onset, duration, severity of disease) and relative brain volume (RBV) as well as T2 lesion load was taken into account., Results: The smaller the CCA at baseline, the slower was SDMT performance at baseline. In a similar way, CCA at follow-up was associated with poor SDMT result at follow-up. Furthermore, the higher the annual rate of change in CCA, the poorer was performance in VDL on the left ear and the more pronounced was the right ear advantage. A positive relationship between performance in VDL right ear and annual rate of change in RBV was also seen. Sensory-motor tests were not significantly associated with CCA. T2 lesion load at baseline was associated with FT performance at baseline. Demographic, clinical and radiological (RBV and T2 lesion load) characteristics did not confound the significant relation between CCA and SDMT., Conclusions: CCA unlike RBV and T2 lesion load was associated with SDMT, which indicated a marked cognitive rather than perceptual-motor component., (© 2012 John Wiley & Sons A/S.)

Background: Sex ratio in multiple sclerosis has been reported from several geographical areas. The disease is more common in women. In Europe the female-to-male ratio varies from 1.1 to 3.4. A recent study from Canada has reported a significant increase, with time, in female-to-male ratio in multiple sclerosis over the last 100 years., Objective: The aim of this study was to analyse any change in sex ratio in multiple sclerosis in the Swedish population., Methods: Data from the Swedish MS Register and data from the Swedish National Statistics Office were used to estimate sex ratio by year of birth and year of onset., Results: In the analysis of sex ratio by year of birth there were 8834 patients (6271 women and 2563 men) born between 1931 and 1985. The mean women-to-men ratio was 2.62. No clear trend was noted for the women-to-men ratio by year of birth (Spearman's rho = 0.345, p = 0.298, n = 11). The number of patients analysed by year of onset was 9098 during the time period 1946 until 2005. The mean women-to-men ratio was 2.57. No significant change in women-to-men ratio (Spearman's rho = -0.007, p = 0.983, n = 12) with time was observed., Conclusion: There is no evidence for an increasing women-to-men ratio with time amongst Swedish multiple sclerosis patients.

Introduction: Multiple sclerosis (MS) has a variable progression with an early onset of atrophy. Individual longitudinal radiological evaluations (over decades) are difficult to perform due to the limited availability of magnetic resonance imaging (MRI) in the past, patients lost in follow-up, and the continuous updating of scanners. We studied a cohort with widespread disease duration at baseline. The observed individual atrophy rates over time of 10 years represented four decades of disease span., Methods: Thirty-seven MS patients (age range 24-65 years with disease duration 1-33 years) were consecutively selected and evaluated with MRI at baseline 1995 and in 1996. They were followed up for a decade (mean of 9.25 years, range 7.3-10 years) up to 2003-2005. Brain parenchymal volume and volumes of the supratentorial ventricles were analyzed with semi-automated volumetric measurements at three time points (1995, 1996, and 2003-2005)., Results: Volumetric differences were found over shorter periods of time (1-7 months); however, differences vanished by the end of follow-up. A uniform longitudinal decrease in brain volume and increase in ventricle volumes were found. Frontal horn width (1D) correlated strongest to 3D measures. No statistical differences of atrophy rates between MS courses were found. Supratentorial ventricular volumes were associated with disability and this association persisted during follow-up., Conclusion: Despite variable clinical courses, the degenerative effects of MS progression expressed in brain atrophy seem to uniformly progress over longer periods of time. These volumetric changes can be detected using 1D and 2D measurements performed on a routine PACS workstation.

Background: For decades, normalized one-dimensional (1D) measures have been used in the evaluation of brain atrophy. In multiple sclerosis (MS), the use of normalized linear measures over longitudinal follow-up remains insufficiently documented., Purpose: To evaluate the association between different regional atrophy measures and disability in MS patients over four decades in a longitudinal cross-sectional study., Material and Methods: 37 consecutively selected MS patients were included. At baseline, patients had a range of disease duration (1-33 years) and age (24-65 years). Each patient was followed by magnetic resonance imaging (MRI) for a mean of 9.25 years (range 7.3-10 years). Four 1D measures were applied at three time points on axial 5-mm T1-weighted images. Three clinical MS subgroups were represented: relapsing-remitting MS (RRMS), secondary progressive MS (SPMS), and primary progressive MS (PPMS)., Results: There were significant changes in all 1D ratios during follow-up. The Evans ratio (ER) and the bifrontal ratio (BFR) were associated with the development of disability. Changes of ER and BFR reflected more aggressive disease progression, as expressed by MS severity score (MSSS)., Conclusion: All four normalized ratios showed uniform atrophy progression, suggesting a consistent rate of atrophy over long-term disease duration independent of MS course. Disability status correlated with 1D measures, suggesting that serial evaluation of Evans and bifrontal ratios might contribute to the radiological evaluation of MS patients.

Background: In multiple sclerosis (MS), brain atrophy assessed by linear measurements of ventricular widths has been reported to be well correlated with three-dimensional (3D) measurements. Therefore, serial linear measurements with no need for advanced 3D evaluation may be proven to be robust markers of irreversible, destructive changes., Purpose: To evaluate the rate of supratentorial ventricular enlargement representing four decades of disease span., Material and Methods: 37 MS patients with disease duration at baseline ranging from 1 to 33 years were included. The mean time of the individual magnetic resonance imaging (MRI) follow-up was 9.25 years (range 7.3-10 years). Enlargement rate of the third and lateral ventricles was studied over time by applying three linear measurements on axial 5-mm T1-weighted MRI images., Results: Progression of supratentorial ventricular widths during 9 years' follow-up was found. The mean annual width increase of the third ventricle was 0.20 mm (P<0.001, 95% confidence interval [CI] 0.15-0.25), for the frontal horn width 0.32 mm (P<0.001, 95% CI 0.23-0.40), and increase of the intercaudate distance was 0.26 mm (P<0.001, 95% CI 0.19-0.33). The association between these three measurements and disability status persisted at the time of follow-up., Conclusion: We found uniform ventricular enlargement progression during four decades of disease span, suggesting unchanging total brain atrophy progression over time.

Background: In multiple sclerosis (MS), multiple periventricular lesions are commonly the first findings on MRI. However, most of these MS lesions are clinically silent. The brain atrophy rate has shown better correlation to physical disability, but it is not clear how atrophy develops over decades. Corpus callosum forms the roof of the third and lateral ventricles. The corpus callosum area (CCA) in a midsagittal image is age independent in a normal adult population up to the seventh decade; therefore it can be used as a marker for non-age-related, pathological brain atrophy., Objectives: To investigate whether and how CCA decreases in size over time in patients with MS., Methods: In a clinical observational study, 37 patients with MS with a wide range of disease duration at baseline (1-33 years) were followed. Three different MS courses were represented. The mean of individual MRI follow-up was 9 years. Multiple sclerosis severity score (MSSS) was also applied to evaluate disability at baseline and after 9 years of follow-up., Results: A significant decrease in CCA over 9 years (p<0.001) and a persisting association between CCA and the disability status were found. The atrophy rate was similar ever four decades of MS for all MS courses. The mean annual CCA decrease was 9.25 mm2 (1.8%). Surprisingly, atrophy rate did not correlate with sex, disease duration, age at MS onset or MS course., Conclusions: Serial evaluations of CCA might be a robust method in monitoring a non-age-related decrease in CCA, reflecting progression of irreversible destructive changes in MS.

Magnetic resonance imaging (MRI) allows examining inflammation and central nervous system (CNS) tissue damage in patients suffering from multiple sclerosis (MS), a demyelinating disease of the CNS. Using real-time PCR, we quantified mRNA levels of apoptosis regulators CD95, CD95 ligand, caspase-8, -10 and cellular FLICE-inhibitory protein (cFLIP), and cytokines IL-10 and TNF-alpha in blood mononuclear cells of MS patients at the time of MRI examination. Patients with detectable gadolinium-enhancing lesions had lower expression of CD95 and caspase-8 (P<0.05). Lesion load and brain atrophy did not correlate with expression levels of any of the target molecules studied. Disease duration correlated positively with both FLIP/caspase-8 and CD95/CD3 ratios (P<0.05). These results support the notion that the CD95-dependent pathway plays a complex role in the regulation of survival of activated immune cells in MS.

Magnetic resonance imaging (MRI) remains the most valuable tool for monitoring disease activity and progression in patients with multiple sclerosis (MS), a chronic demyelinating disease of the central nervous system (CNS) with presumably autoimmune etiology. Chemokine receptors have been implicated in MS as key molecules directing inflammatory cells into the CNS. Regulatory (CD4+CD25+) T cells (Tr cells) are important in suppressing autoimmunity, and their absolute or functional deficit could be expected in MS. In the present study, venous blood was obtained from MS patients concurrent with MRI examination of the brain, and expression of chemokine receptors CCR1, CCR2, CCR5, CXCR3 and CXCR4 by CD4 T cells and monocytes, proportions of Tr cells, as well as expression of CD45RO, CD95, CTLA-4, HLA-DR and interleukin (IL)-10 by Tr cells and non-Tr (CD25-) CD4 T cells was analyzed by flow cytometry. Surface expression of CXCR3 by CD4 T cells was downregulated in the group of patients with high lesion load (LL) on T2-weighted images and gadolinium (Gd)-enhancing lesions on T1-weighted images, compared to the group with high LL and no Gd-enhancing lesions, and to the group with low LL, suggesting internalization of CXCR3 due to the release of its chemokine ligand (IP-10/CXCL10) from active MS lesions. Proportions of Tr cells amongst all CD4 T cells, and expression of IL-10 by Tr cells were increased in the patients with high LL and Gd-enhancing lesions. These results suggest that there is correlation between MRI parameters, chemokine receptor expression and the status of circulating Tr cells in MS, but further studies need to discriminate between pathogenetically relevant and bystander phenomena.

To quantify and characterize seasonal variation in monosymptomatic optic neuritis (MON) onsets, multiple sclerosis (MS) onsets and MS exacerbations (MSE), a meta-analysis was performed, using established methods and pooling weighted information obtained from nine reports on MON, six reports on MS onsets and nine reports on MSE, which fulfilled specific criteria for report quality and data homogeneity. The results suggested that MON, MS onsets and MSE in the Northern hemisphere present a similar pattern with highest frequencies in spring and lowest in winter. These differences were highest for MS onsets, 45% with 95% CI 36-55%, and lowest for MSE, 10% with 95% CI 7-13%, statistically significant and robust, insensitive to an alternative seasonal definition, not unduly influenced by any single primary study, and supported by fail-safe N calculations. Random variation, misclassification and publication bias were less likely to account for the reported generalized seasonal patterns.

Localized short echo time magnetic resonance (MR) spectra were obtained from patients with multiple sclerosis of relapsing-remitting or secondary chronic-progressive course and from healthy controls. Automated analysis using model spectra, sensitivity correction, and subtraction of partial ventricular volume yielded tissue concentrations of metabolites that were in line with findings of previous studies. Additional findings were increased creatine in chronic lesions and increased myo-inositol in normal-appearing white matter. Regression analysis was performed to reveal concomitant changes of metabolite concentrations. Differences in the correlations between cholines and myo-inositol suggest increased expression of myo-inositol in chronic lesions or of cholines in active, contrast-enhanced lesions. A correlation between N-acetyl-aspartate and creatine, which is probably due to extracellular edema, was observed in active but not in chronic lesions. Creatine and cholines correlated in chronic lesions, which may be the result of gliosis. The consequences of these findings for the interpretation of absolute concentrations and creatine ratios are discussed.

Enhanced expression of pro- and anti-inflammatory cytokines is a common finding in MS, but attempts to correlate cytokine expression with disease activity have produced conflicting results. In this paper, gadolinium-(Gd-)enhancing lesions on brain MRI were used as markers for active inflammation in patients with MS not treated with any immunomodulatory drugs. In parallel, in situ hybridization was used to detect blood and cerebrospinal fluid (CSF) mononuclear cells (MNC) expressing cytokine mRNA. An association was observed between numbers of perforin mRNA expressing CSF MNC and numbers of Gd-enhancing brain MRI lesions. Perforin mRNA expressing CSF MNC were not detected in any of the patients lacking active lesions on brain MRI. The expression of tumor necrosis factor-alpha, interleukin-10 (IL-10) and IL-12 mRNA in CSF MNC did not differ between MS patients with and without active MRI lesions. Based on the present finding, a role for perforin in the disruption of the blood-brain barrier in MS can be hypothesized.

The article presents a study on the effect of an immunomodulatory treatment in delaying the secondary progression (SP) of relapsing-remitting multiple sclerosis (RRMS). Methods used include survival analysis, Gothenburg Incidence Cohort (GIC), and Cox regression models. Result shows that disease modifying drugs (DMDs) slows the SP process of RRMS.

Objective To estimate the cost-effectiveness of a new treatment (natalizumab) for multiple sclerosis (MS) compared with current standard therapy with disease-modifying drugs (DMDs) in Sweden. Methods A Markov model was constructed to illustrate disease progression based on functional disability (the Expanded Disability Status Scale (EDSS)). The effectiveness of natalizumab was based on a 2-year clinical trial in 942 patients (AFFIRM). The effectiveness of current DMDs was estimated from a matched sample of 512 patients in the Stockholm MS registry. Patients withdrawing from treatment were assumed to follow the disease course of 824 patients with relapsing-remitting disease at onset in the Ontario natural history cohort. Costs and utilities are based on a recent observational study in 1339 patients. All data sets were available at the patient level. Main results are presented from the societal perspective, over a 20-year time frame, in 2005 Euros (€1 = 9.25 SEK). Results In the base case, treatment with natalizumab was less expensive and more effective than treatment with current DMDs. When only healthcare costs were considered, the cost per quality-adjusted life year gained with natalizumab was €38 145. Results are sensitive only to the time horizon of the analysis and assumptions about effectiveness of natalizumab beyond the trial. Conclusions This cost-effectiveness analysis used registry data, cohort and observational studies to extrapolate the efficacy findings of natalizumab from the AFFIRM clinical trial to measure effectiveness in clinical practice. The analysis results suggest that for the population considered, natalizumab provides an additional health benefit at a similar cost to current DMDs from a societal perspective. [ABSTRACT FROM AUTHOR]