Is Time to Reach EDSS 6.0 Faster in Patients with Late-Onset versus Young-Onset Multiple Sclerosis?

MethodsThis cross-sectional cohort study was conducted to identify LOMS and YOMS patients’ with relapsing remitting course at MS diagnosis. Time (years) to reach sustained EDSS 6.0 was compared between LOMS and AOMS patients. Cox proportional hazards model was used to evaluate the demographic and clinical predictors of time to EDSS 6.0 in these cohorts.ResultsLOMS and YOMS cohorts comprised 99 (10.7%) and 804 (89.3%) patients respectively. Spinal cord presentation at MS onset was more common among LOMS patients (46.5% vs. 32.3%). The proportions of LOMS and YOMS patients reaching EDSS 6.0 during the follow-up period were 19.2% and 15.7% respectively. In multivariable Cox proportional hazards model, older age at MS onset (adjusted hazard ratio (aHR) = 3.96; 95% CI: 2.14–7.32; p < 0.001), male gender (aHR = 1.85; 95% CI: 1.22–2.81; p = 0.004) and spinal cord presentation at onset (aHR = 1.47; 95% CI: 0.98–2.21; p = 0.062) were significantly associated with shorter time to EDSS 6.0.ConclusionsLOMS patients attained EDSS 6.0 in a significantly shorter period that was influenced by male gender and spinal cord presentation at MS onset.     

Is Metabolic Flexibility Altered in Multiple Sclerosis Patients?

Objectives

Metabolic flexibility is defined as ability to adjust fuel oxidation to fuel availability. Multiple sclerosis (MS) results in reduced muscle strength and exercise intolerance. We tested the hypothesis that altered metabolic flexibility contributes to exercise intolerance in MS patients.

Methods

We studied 16 patients (all on glatiramer) and 16 matched healthy controls. Energy expenditure (EE), and carbohydrate (COX) and lipid oxidation (LOX) rates were determined by calorimetry, before and after an oral glucose load. We made measurements either at rest (canopy device) or during 40 min low-grade (0.5 W/kg) exercise (metabolic chamber). We also obtained plasma, and adipose tissue and skeletal muscle dialysate samples by microdialysis to study tissue-level metabolism under resting conditions.

Results

At rest, fasting and postprandial plasma glucose, insulin, and free fatty acid levels did not differ between patients and controls. Fasting and postprandial COX was higher and LOX lower in patients. In adipose, fasting and postprandial dialysate glucose, lactate, and glycerol levels were higher in patients vs. controls. In muscle, fasting and postprandial dialysate metabolite levels did not differ significantly between the groups. During exercise, EE did not differ between the groups. However, COX increased sharply over 20 min in patients, without reaching a steady state, followed by an immediate decrease within the next 20 min and fell even below basal levels after exercise in patients, compared to controls.

Conclusions

Glucose tolerance is not impaired in MS patients. At rest, there is no indication for metabolic inflexibility or mitochondrial dysfunction in skeletal muscle. The increased adipose tissue lipolytic activity might result from glatiramer treatment. Autonomic dysfunction might cause dysregulation of postprandial thermogenesis at rest and lipid mobilization during exercise.     

Preserved Antigen-Specific Immune Response in Patients with Multiple Sclerosis Responding to IFNβ-Therapy

Background

Interferon-beta (IFNβ) regulates the expression of a complex set of pro- as well as anti-inflammatory genes. In cohorts of MS patients unstratified for therapeutic response to IFNβ, normal vaccine-specific immune responses have been observed. Data capturing antigen-specific immune responses in cohorts of subjects defined by response to IFNβ-therapy are not available.

Objective

To assess antigen-specific immune responses in a cohort of MS patients responding clinically and radiologically to IFNβ.

Methods

In 26 MS patients, clinical and MRI disease activity were assessed before and under treatment with IFNβ. Humoral and cellular immune response to influenza vaccine was prospectively characterized in these individuals, and 33 healthy controls by influenza-specific Enzyme-Linked Immunosorbent Assay (ELISA) and Enzyme Linked Immuno Spot Technique (ELISPOT).

Results

Related to pre-treatment disease activity, IFNβ reduced clinical and radiological MS disease-activity. Following influenza vaccination, frequencies of influenza-specific T cells and concentrations of anti-influenza A and B IgM and IgG increased comparably in MS-patients and in healthy controls.

Conclusions

By showing in a cohort of MS-patients responding to IFNβ vaccine-specific immune responses comparable to controls, this study indicates that antigen-specific immune responses can be preserved under successful IFNβ-therapy.     

Variables Related to Working Capability among Swiss Patients with Multiple Sclerosis—A Cohort Study

Introduction

Reduced working capability is one of the most devastating consequences of multiple sclerosis (MS). We aimed to study working capability and related variables in Swiss MS patients.

Materials and Methods

A cross-sectional analysis of employment status and risk factors for reduced working capability among MS patients treated at our outpatient clinic. A questionnaire was mailed to 644 MS patients and returned by 69.7%. 405 patients (66% female, mean age 44.2 years (SD±10.2), median EDSS 3.0 (SD±1.8)) were eligible for subsequent analysis.

Results

After a mean disease duration of 12.3 years (SD±8.25), full or part time employment was declared by 26.7% and 25.7%, respectively. Incapacity to work was reported by 27.1%. A total of 52.8% specified MS as the cause for altered working capability, whereas 20.5% cited reasons unrelated to the disorder. Even with minimal disability (EDSS<3) a significant proportion of patients (24%) reported reduced working capability. Among the MS-specific restricting factors were fatigue (47.6%), sensorimotor deficits (31.1%), impaired vision (3.3%) and pain (2.8%).

Conclusion

MS continues to takes its toll on the professional life of the patients early in the course. While complete incapacity becomes relevant with moderate to severe disability, many patients scale down to part-time even with minimal impairment.     

Endogenous Interferon-β-Inducible Gene Expression and Interferon-β-Treatment Are Associated with Reduced T Cell Responses to Myelin Basic Protein in Multiple Sclerosis

Autoreactive CD4⁺ T-cells are considered to play a major role in the pathogenesis of multiple sclerosis. In experimental autoimmune encephalomyelitis, an animal model of multiple sclerosis, exogenous and endogenous type I interferons restrict disease severity. Recombinant interferon-β is used for treatment of multiple sclerosis, and some untreated multiple sclerosis patients have increased expression levels of type I interferon-inducible genes in immune cells. The role of endogenous type I interferons in multiple sclerosis is controversial: some studies found an association of high expression levels of interferon-β-inducible genes with an increased expression of interleukin-10 and a milder disease course in untreated multiple sclerosis patients, whereas other studies reported an association with a poor response to treatment with interferon-β. In the present study, we found that untreated multiple sclerosis patients with an increased expression of interferon-β-inducible genes in peripheral blood mononuclear cells and interferon-β-treated multiple sclerosis patients had decreased CD4⁺ T-cell reactivity to the autoantigen myelin basic protein ex vivo. Interferon-β-treated multiple sclerosis patients had increased IL10 and IL27 gene expression levels in monocytes in vivo. In vitro, neutralization of interleukin-10 and monocyte depletion increased CD4⁺ T-cell reactivity to myelin basic protein while interleukin-10, in the presence or absence of monocytes, inhibited CD4⁺ T-cell reactivity to myelin basic protein. Our findings suggest that spontaneous expression of interferon-β-inducible genes in peripheral blood mononuclear cells from untreated multiple sclerosis patients and treatment with interferon-β are associated with reduced myelin basic protein-induced T-cell responses. Reduced myelin basic protein-induced CD4⁺ T-cell autoreactivity in interferon-β-treated multiple sclerosis patients may be mediated by monocyte-derived interleukin-10.     

Adenosine Deaminase and 5′Nucleotidase Activities in Peripheral Blood T Cells of Multiple Sclerosis Patients

Multiple sclerosis (MS) is one of the most common causes of neurological disability in young and middle-aged adults and is thought to be mediated by autoreactive T cells. Activities of adenosine deaminase (ADA) and 5′(nucleotidase (5′NT), which are involved in the differentiation and maturation of the lymphoid system, were measured in peripheral blood T cells from 21 MS patients and in 23 age and sex matched healthy controls to determine whether an association existed between these enzyme abnormalities and cellular immune functions. ADA and 5′NT activities were found significantly decreased in MS patients (P < .001 and P < .01 respectively) when compared with controls. Low levels of ADA and 5′NT activities were found irrespective of whether patients had relapsing–remitting or chronic progressive MS. These findings suggest that low levels of these enzyme activities in T cells may be related to the persistent abnormalities in T cell function in the clinical course of MS.     

Can Survival Prediction Be Improved By Merging Gene Expression Data Sets?

Background

High-throughput gene expression profiling technologies generating a wealth of data, are increasingly used for characterization of tumor biopsies for clinical trials. By applying machine learning algorithms to such clinically documented data sets, one hopes to improve tumor diagnosis, prognosis, as well as prediction of treatment response. However, the limited number of patients enrolled in a single trial study limits the power of machine learning approaches due to over-fitting. One could partially overcome this limitation by merging data from different studies. Nevertheless, such data sets differ from each other with regard to technical biases, patient selection criteria and follow-up treatment. It is therefore not clear at all whether the advantage of increased sample size outweighs the disadvantage of higher heterogeneity of merged data sets. Here, we present a systematic study to answer this question specifically for breast cancer data sets. We use survival prediction based on Cox regression as an assay to measure the added value of merged data sets.

Results

Using time-dependent Receiver Operating Characteristic-Area Under the Curve (ROC-AUC) and hazard ratio as performance measures, we see in overall no significant improvement or deterioration of survival prediction with merged data sets as compared to individual data sets. This apparently was due to the fact that a few genes with strong prognostic power were not available on all microarray platforms and thus were not retained in the merged data sets. Surprisingly, we found that the overall best performance was achieved with a single-gene predictor consisting of CYB5D1.

Conclusions

Merging did not deteriorate performance on average despite (a) The diversity of microarray platforms used. (b) The heterogeneity of patients cohorts. (c) The heterogeneity of breast cancer disease. (d) Substantial variation of time to death or relapse. (e) The reduced number of genes in the merged data sets. Predictors derived from the merged data sets were more robust, consistent and reproducible across microarray platforms. Moreover, merging data sets from different studies helps to better understand the biases of individual studies and can lead to the identification of strong survival factors like CYB5D1 expression.     

Can Global Weed Assemblages Be Used to Predict Future Weeds?

Predicting which plant taxa are more likely to become weeds in a region presents significant challenges to both researchers and government agencies. Often it is done in a qualitative or semi-quantitative way. In this study, we explored the potential of using the quantitative self-organising map (SOM) approach to analyse global weed assemblages and estimate likelihoods of plant taxa becoming weeds before and after they have been moved to a new region. The SOM approach examines plant taxa associations by analysing where a taxon is recorded as a weed and what other taxa are recorded as weeds in those regions. The dataset analysed was extracted from a pre-existing, extensive worldwide database of plant taxa recorded as weeds or other related status and, following reformatting, included 187 regions and 6690 plant taxa. To assess the value of the SOM approach we selected Australia as a case study. We found that the key and most important limitation in using such analytical approach lies with the dataset used. The classification of a taxon as a weed in the literature is not often based on actual data that document the economic, environmental and/or social impact of the taxon, but mostly based on human perceptions that the taxon is troublesome or simply not wanted in a particular situation. The adoption of consistent and objective criteria that incorporate a standardized approach for impact assessment of plant taxa will be necessary to develop a new global database suitable to make predictions regarding weediness using methods like SOM. It may however, be more realistic to opt for a classification system that focuses on the invasive characteristics of plant taxa without any inference to impacts, which to be defined would require some level of research to avoid bias from human perceptions and value systems.     

Can Amphipod Behavior Help to Predict Chronic Toxicity of Sediments?

Amphipods are widely used in both acute and chronic (sub-lethal) sediment tests. Acute sediment tests provide relatively rapid results, but may fail to detect moderately toxic contaminants that are bound to the sediment, whereas chronic life-cycle tests are rarely performed as they are time consuming and expensive. Observations during chronic testing of oil-contaminated sediment suggested that there may be a link between the behavior of the marine amphipod Corophium volutator and reduction in growth rate. Behavior tests were performed with six individual amphipods per treatment using sediment spiked with weathered Forties oil with burrowing time, re-emergence from sediment, and activity prior to burrowing as endpoints. Further behavior tests were used to predict the chronic toxicity of sediments spiked with three crude oils each with a dominant unresolved complex mixture of hydrocarbons (UCM). The effect of sediment type on behavior was also investigated. The results suggested that although the behavior test could not be used alone as a viable alternative to sediment toxicity tests, it could prove useful as an adjunct to acute tests, and help select sediments that deserve further investigation.     

Gene Expression Profile of Peripheral Blood Lymphocytes from Renal Cell Carcinoma Patients Treated with IL-2, Interferon-�� and Dendritic Cell Vaccine

Lymphocytes are a key component of the immune system and their differentiation and function are directly influenced by cancer. We examined peripheral blood lymphocyte (PBL) gene expression as a biomarker of illness and treatment effect using the Affymetrix Human Gene ST1 platform in patients with metastatic renal cell carcinoma (mRCC) who received combined treatment with IL-2, interferon-?-2a and dendritic cell vaccine. We examined gene expression, cytokine levels in patient serum and lymphocyte subsets as determined by flow cytometry (FCM). Pre-treatment PBLs from patients with mRCC exhibit a gene expression profile and serum cytokine profile consistent with inflammation and proliferation not found in healthy donors (HD). PBL gene expression from patients with mRCC showed increased mRNA of genes involved with T-cell and T_REG-cell activation pathways, which was also reflected in lymphocyte subset distribution. Overall, PBL gene expression post-treatment (POST) was not significantly different than pre-treatment (PRE). Nevertheless, treatment related changes in gene expression (post-treatment minus pre-treatment) revealed an increased expression of T-cell and B-cell receptor signaling pathways in responding (R) patients compared to non-responding (NR) patients. In addition, we observed down-regulation of T_REG-cell pathways post-treatment in R vs. NR patients. While exploratory in nature, this study supports the hypothesis that enhanced inflammatory cytotoxic pathways coupled with blunting of the regulatory pathways is necessary for effective anti-cancer activity associated with immune therapy. This type of analysis can potentially identify additional immune therapeutic targets in patients with mRCC.     

Do Treatment Quality Indicators Predict Cardiovascular Outcomes in Patients with Diabetes?

Background

Landmark clinical trials have led to optimal treatment recommendations for patients with diabetes. Whether optimal treatment is actually delivered in practice is even more important than the efficacy of the drugs tested in trials. To this end, treatment quality indicators have been developed and tested against intermediate outcomes. No studies have tested whether these treatment quality indicators also predict hard patient outcomes.

Methods

A cohort study was conducted using data collected from >10.000 diabetes patients in the Groningen Initiative to Analyze Type 2 Treatment (GIANTT) database and Dutch Hospital Data register. Included quality indicators measured glucose-, lipid-, blood pressure- and albuminuria-lowering treatment status and treatment intensification. Hard patient outcome was the composite of cardiovascular events and all-cause death. Associations were tested using Cox regression adjusting for confounding, reporting hazard ratios (HR) with 95% confidence intervals.

Results

Lipid and albuminuria treatment status, but not blood pressure lowering treatment status, were associated with the composite outcome (HR = 0.77, 0.67–0.88; HR = 0.75, 0.59–0.94). Glucose lowering treatment status was associated with the composite outcome only in patients with an elevated HbA1c level (HR = 0.72, 0.56–0.93). Treatment intensification with glucose-lowering but not with lipid-, blood pressure- and albuminuria-lowering drugs was associated with the outcome (HR = 0.73, 0.60–0.89).

Conclusion

Treatment quality indicators measuring lipid- and albuminuria-lowering treatment status are valid quality measures, since they predict a lower risk of cardiovascular events and mortality in patients with diabetes. The quality indicators for glucose-lowering treatment should only be used for restricted populations with elevated HbA1c levels. Intriguingly, the tested indicators for blood pressure-lowering treatment did not predict patient outcomes. These results question whether all treatment indicators are valid measures to judge quality of health care and its economics.     

Subcutaneous Interferon β-1a May Protect against Cognitive Impairment in Patients with Relapsing–Remitting Multiple Sclerosis: 5-Year Follow-up of the COGIMUS Study

Objective

To assess the effects of subcutaneous (sc) interferon (IFN) -1a on cognition over 5 years in mildly disabled patients with relapsing–remitting multiple sclerosis (RRMS).

Methods

Patients aged 18–50 years with RRMS (Expanded Disability Status Scale score ≤4.0) who had completed the 3-year COGIMUS study underwent standardized magnetic resonance imaging, neurological examination, and neuropsychological testing at years 4 and 5. Predictors of cognitive impairment at year 5 were identified using multivariate analysis.

Results

Of 331 patients who completed the 3-year COGIMUS study, 265 participated in the 2-year extension study, 201 of whom (75.8%; sc IFN β-1a three times weekly: 44 µg, n = 108; 22 µg, n = 93) completed 5 years'' follow-up. The proportion of patients with cognitive impairment in the study population overall remained stable between baseline (18.0%) and year 5 (22.6%). The proportion of patients with cognitive impairment also remained stable in both treatment groups between baseline and year 5, and between year 3 and year 5. However, a significantly higher proportion of men than women had cognitive impairment at year 5 (26.5% vs 14.4%, p = 0.046). Treatment with the 22 versus 44 µg dose was predictive of cognitive impairment at year 5 (hazard ratio 0.68; 95% confidence interval 0.48–0.97).

Conclusions

This study suggests that sc IFN β-1a dose-dependently stabilizes or delays cognitive impairment over a 5-year period in most patients with mild RRMS. Women seem to be more protected against developing cognitive impairment, which may indicate greater response to therapy or the inherently better prognosis associated with female sex in MS.     

Is the Concept of Quality of Life Relevant for Multiple Sclerosis Patients with Cognitive Impairment? Preliminary Results of a Cross-Sectional Study

Background

Cognitive impairment occurs in about 50% of multiple sclerosis (MS) patients, and the use of self-reported outcomes for evaluating treatment and managing care among subjects with cognitive dysfunction has been questioned. The aim of this study was to provide new evidence about the suitability of self-reported outcomes for use in this specific population by exploring the internal structure, reliability and external validity of a specific quality of life (QoL) instrument, the Multiple Sclerosis International Quality of Life questionnaire (MusiQoL).

Methods

Design: cross-sectional study. Inclusion criteria: MS patients of any disease subtype. Data collection: sociodemographic (age, gender, marital status, education level, and occupational activity) and clinical data (MS subtype, Expanded Disability Status Scale, disease duration); QoL (MusiQoL and SF36); and neuropsychological performance (Stroop color-word test). Statistical analysis: confirmatory factor analysis, item-dimension correlations, Cronbach''s alpha coefficients, Rasch statistics, relationships between MusiQoL dimensions and other parameters.

Principal Findings

One hundred and twenty-four consecutive patients were enrolled. QoL scores did not differ between the 69 cognitively non-impaired patients and the 55 cognitively impaired patients, except for the symptoms dimension. The confirmatory factor analysis performed among the impaired subjects showed that the structure of the questionnaire matched with the initial structure of the MusiQoL. The unidimensionality of the MusiQoL dimensions was preserved, and the internal validity indices were satisfactory and close to those of the reference population.

Conclusions/Significance

Our study suggests that executive dysfunction did not compromise the reliability and the validity of the self-reported QoL questionnaires.     

Pharmacogenomics of Interferon-? Therapy in Multiple Sclerosis: Baseline IFN Signature Determines Pharmacological Differences between Patients

Background

Multiple sclerosis (MS) is a heterogeneous disease. In order to understand the partial responsiveness to IFNß in Relapsing Remitting MS (RRMS) we studied the pharmacological effects of IFNß therapy.

Methodology

Large scale gene expression profiling was performed on peripheral blood of 16 RRMS patients at baseline and one month after the start of IFNß therapy. Differential gene expression was analyzed by Significance Analysis of Microarrays. Subsequent expression analyses on specific genes were performed after three and six months of treatment. Peripheral blood mononuclear cells (PBMC) were isolated and stimulated in vitro with IFNß. Genes of interest were measured and validated by quantitative realtime PCR. An independent group of 30 RRMS patients was used for validation.

Principal Findings

Pharmacogenomics revealed a marked variation in the pharmacological response to IFNß between patients. A total of 126 genes were upregulated in a subset of patients whereas in other patients these genes were downregulated or unchanged after one month of IFNß therapy. Most interestingly, we observed that the extent of the pharmacological response correlates negatively with the baseline expression of a specific set of 15 IFN response genes (R = −0.7208; p = 0.0016). The negative correlation was maintained after three (R = −0.7363; p = 0.0027) and six (R = −0.8154; p = 0.0004) months of treatment, as determined by gene expression levels of the most significant correlating gene. Similar results were obtained in an independent group of patients (n = 30; R = −0.4719; p = 0.0085). Moreover, the ex vivo results could be confirmed by in vitro stimulation of purified PBMCs at baseline with IFNß indicating that differential responsiveness to IFNß is an intrinsic feature of peripheral blood cells at baseline.

Conclusion

These data imply that the expression levels of IFN response genes in the peripheral blood of MS patients prior to treatment could serve a role as biomarker for the differential clinical response to IFNß.