Global transcriptome profiling of mild relapsing-remitting versus primary progressive multiple sclerosis.

BACKGROUND AND PURPOSE: Genetic research in multiple sclerosis (MS) mostly compares patients with MS with healthy controls, but does not differentiate between MS disease courses. We compared peripheral blood gene expression patterns between extremes of MS phenotypes, i.e. patients with mild relapsing-remitting MS (mRRMS) and primary progressive MS (PPMS). METHODS: We analyzed global gene expression profiles of peripheral blood samples of age- and gender-matched patients with mRRMS and PPMS. Detailed bioinformatic and gene set enrichment analysis, pathway and principle component analyses were used to identify differentially expressed genes and pathways. RESULTS: A total of 84 genes were significantly deregulated between the groups. Of those, 19 had been previously reported to be deregulated in patients with MS as compared with healthy controls, including major histocompatibility complex, interferon receptor 2 and interleukin 6 receptor. Detailed molecular pathway analysis revealed significant up-regulation of antigen processing and presentation, leukocyte transendothelial migration, nucleotide-binding oligomerization domain-like receptor signaling, chemokine signaling and down-regulation of RNA transport, spliceosome and aminoacyl-tRNA biosynthesis pathways in PPMS compared with mRRMS. CONCLUSION: Our analyses show significant differences between mRRMS and PPMS gene expression. Surprisingly, the differentially expressed genes were mostly involved in immunological and inflammatory pathways, suggesting that the difference in MS phenotypes is caused primarily by a difference in immune responses. It should be kept in mind that our analyses were in peripheral blood only, and that the observed differences in inflammatory pathways may be a substrate of the analysed tissue. Further research into gene expression differences between disease courses including analyses in central nervous system tissue is warranted.

Smoking does not influence disability accumulation in primary progressive multiple sclerosis.

BACKGROUND AND PURPOSE: The modifiable risk factor cigarette smoking has been associated with an increased risk of developing multiple sclerosis (MS) and with disease activity in relapsing-remitting MS. However, less is known about the effect of smoking on disease progression in progressive MS. Here the association between cigarette smoking and disability accumulation in primary progressive MS (PPMS) is investigated. METHODS: Kaplan-Meier survival analyses and Cox proportional hazard modelling were used to investigate the influence of cigarette smoking on the risk of reaching Expanded Disability Status Scale (EDSS) 4 and 6 as well as the time from EDSS 4 to 6 in patients with PPMS. RESULTS: In all, 416 patients with PPMS and available smoking history were identified. Median time to EDSS 4 was 4 years in ever-smokers and 5 years in never-smokers (P = 0.27), and it was 9 years to EDSS 6 in both ever-smokers and never-smokers (P = 0.48). Smokers were not at increased risk of faster progression to EDSS 4, 6 and from EDSS 4 to 6. Age at disease onset was the strongest risk factor for progression to EDSS 4, 6 and from EDSS 4 to 6. CONCLUSIONS: Our investigation of a large and well-characterized population based PPMS cohort suggests that cigarette smoking does not influence disability accumulation in PPMS. Our findings support the idea that PPMS is driven by different underlying pathomechanisms than relapsing-remitting MS.

Application and a proposed modification of the 2010 McDonald criteria for the diagnosis of multiple sclerosis in a Canadian cohort of patients with clinically isolated syndromes.

BACKGROUND: The 2005 and 2010 McDonald criteria utilize magnetic resonance imaging (MRI) to provide evidence of disease dissemination in space (DIS) and time (DIT) for the diagnosis of multiple sclerosis (MS) in patients who have clinically isolated syndromes (CIS). METHODS: Data from 109 CIS patients not satisfying the 2005 criteria at entry into a randomized controlled minocycline trial were analyzed to determine the proportion who would have been diagnosed with MS at screening based on 2010 criteria. The impact of including symptomatic, as well as asymptomatic, MRI lesions to confirm DIT was also explored. RESULTS: Thirty percent (33/109) of patients, retrospectively, met the 2010 criteria for a diagnosis of MS at baseline. When both symptomatic and asymptomatic lesions were used to confirm DIT, three additional patients met the 2010 criteria. There was a significant 10.1% increase in the proportion of patients who met the 2010 DIS criteria, compared with the 2005 DIS criteria; however, two patients satisfied the 2005 DIS but not 2010 DIS criteria. CONCLUSION: Using 2010 McDonald criteria, 30% of the CIS patients could be diagnosed with MS using a single MRI scan. Inclusion of symptomatic lesions in the DIT criteria further increases this proportion to 33%.

Corpus callosum volume and interhemispheric transfer in multiple sclerosis.

BACKGROUND: The corpus callosum (CC) is frequently compromised in patients with multiple sclerosis (MS). Structural and functional measurements of the CC may be useful to monitor the progression of the disease. The aim of this pilot study was to determine if bimanual tactile temporal thresholds correlates with CC volume. A tactile temporal threshold is the longest temporal interval that separates the onsets of two tactile stimuli when they are judged by the observer as simultaneous. Judgments to bimanual stimulations require interhemispheric transfer via the CC. METHODS: Thresholds were examined in MS patients and matched controls. Magnetic resonance (MR) images were acquired on a 3T MR system within 48 hours of clinical assessment and measurement of thresholds. RESULTS: Corpus callosum volume was assessed by using a semiautomatic livewire algorithm. The CC volume was smaller (by 21% on average, p < 0.01) and thresholds were higher (by 49% on average, p < 0.03) in MS patients when compared to controls. A significant correlation (r = -0.66, p = 0.01) between CC volume and thresholds emerged for the MS patients. CONCLUSION: Measuring treatment benefits of neuroprotective and repair therapies is a well recognized challenge in MS research. The overall findings of this study suggest that these measurements, which involve the transfer of information interhemispherically via the CC, may be promising outcome measures that warrant further scientific exploration to develop a model to measure recovery.

3T deep gray matter T2 hypointensity correlates with disability over time in stable relapsing-remitting multiple sclerosis: a 3-year pilot study.

Abnormally decreased deep gray matter (GM) signal intensity on T2-weighted MRI (T2 hypointensity) is associated with brain atrophy and disability progression in patients with multiple sclerosis (MS) and is believed to represent excessive iron deposition. We investigated the time course of deep GM T2 hypointensity and its relationship with disability at 3T in 8 stable relapsing-remitting (RR) MS patients treated with minocycline over 3years. MRI and disability measurements were compared at baseline, 6, 12, 24, and 36months. Grand mean deep GM T2 hypointensity was negatively correlated with EDSS over time (r=-0.94, P=0.02). This correlation was strongest in the head of caudate (r=-0.95, P=0.01) and putamen (r=-0.89, P=0.04). Additionally, baseline grand mean deep GM T2 hypointensity appears to predict third year EDSS (r=-0.72, P=0.04). These results suggest that iron associated deep GM injury correlates with patient disability in stable RRMS. Measurements of deep GM T2 hypointensity at high field MRI may prove to be useful in monitoring individuals with MS. Further studies are required to confirm these results in a large sample and to determine if T2 hypointensity changes in clinically active MS patients.

Glatiramer acetate in combination with minocycline in patients with relapsing--remitting multiple sclerosis: results of a Canadian, multicenter, double-blind, placebo-controlled trial.

Minocycline is proposed as an add-on therapy to improve the efficacy of glatiramer acetate in relapsing-remitting multiple sclerosis. The effect of minocycline plus glatiramer acetate was evaluated in this double-blind, placebo-controlled study by determining the total number of T1 gadolinium-enhanced lesions at months 8 and 9 in patients who were starting glatiramer acetate and had at least one T1 gadolinium-enhanced lesion on screening magnetic resonance imaging. Forty-four participants were randomized to either minocycline 100 mg twice daily or matching placebo for 9 months as add-on therapy. They were assessed at screening and months 1, 3, 6, 8 and 9. Forty participants completed the study. Compared with glatiramer acetate/placebo, glatiramer acetate/minocycline reduced the total number of T1 gadolinium-enhanced lesions by 63% (mean 1.47 versus 2.95; p = 0.08), the total number of new and enlarging T2 lesions by 65% (mean 1.84 versus 5.14; p = 0.06), and the total T2 disease burden (p = 0.10). A higher number of gadolinium-enhanced lesions were present in the glatiramer acetate/minocycline group at baseline; this was incorporated into the analysis of the primary endpoint but makes interpretation of the data more challenging. The risk of relapse tended to be lower in the combination group (0.19 versus 0.41; p = NS). Treatment was safe and well tolerated. We conclude that efficacy endpoints showed a consistent trend favoring combination treatment. As minocycline is a relatively safe oral therapy, further study of this combination is warranted in relapsing-remitting multiple sclerosis.

High dose oral steroids commonly used to treat relapses in Canadian MS clinics.

BACKGROUND: Glucocorticoid treatment improves the speed of functional recovery of acute multiple sclerosis (MS) relapses but has not been shown to provide any long-term functional benefit. There is currently no convincing evidence that the clinical benefit is influenced by the route of administration or the dosage of glucocorticoid, or the particular glucocorticoid prescribed. Recent studies support similarities in the bioequivalence and in the clinical effect of high dose oral corticosteroids for MS relapses. OBJECTIVE: This survey aimed to determine the relapse treatment preferences of clinicians in Canadian MS clinics. METHODS: Members of the Canadian Network of MS Clinics are linked by an email server. A one page survey was distributed to the group to determine and report use of corticosteroids to manage MS relapses amongst Canadian MS specialists. RESULTS: Fifty-one clinicians from 17 MS clinics were surveyed. 32 (63%) surveys were returned representing 16 clinics. Five doses are most commonly prescribed, usually without a taper. Three or four doses and the use of a corticosteroid taper, however, are not uncommon. Gastric cytoprotection and sedatives are often prescribed for use as needed. CONCLUSION: This survey illustrates that when Canadian clinicians with expertise in managing MS treat MS relapses they choose high dose corticosteroids, either oral or i.v. The results therefore represent Canadian practice as these clinicians provide direct patient care and influence care by community neurologists. Until evidence clearly identifies a superior practice all options should be available to clinicians and their patients.

Ethics of placebo-controlled clinical trials in multiple sclerosis: a reassessment.

The increasing number of established effective therapies for relapsing multiple sclerosis (MS) and emerging consensus for early treatment raise practical concerns and ethical dilemmas for placebo-controlled clinical trials in this disease. An international group of clinicians, ethicists, statisticians, regulators, and representatives from the pharmaceutical industry convened to reconsider prior recommendations regarding the ethics of placebo-controlled trials in MS. The group concluded that placebo-controlled trials can still be done ethically, with restrictions. For patients with relapsing MS for which established effective therapies exist, placebo-controlled trials should only be offered with rigorous informed consent if the subjects refuse to use these treatments, have not responded to them, or if these treatments are not available to them for other reasons (e.g., economics). Suggestions are provided to protect subject autonomy and improve informed consent procedures. Recommendations are tighter than previously suggested for placebo-controlled trials in "resource-restricted" environments where established therapies may not be available. Guidance is also provided on the ethics of alternative trial designs and the balance between study subject burden and risk, scientific rationale and interpretability of trial outcomes.

Anti-depressant use in association with interferon and glatiramer acetate treatment in multiple sclerosis.

BACKGROUND: Randomized controlled trials incorporating validated depression scales have failed to identify an association between interferon beta treatment and depression in MS. This is surprising since interferons used in other clinical contexts are considered capable of causing depression. The negative results in MS could be due inadequate power in the published trials. METHODS: In this study, longitudinal data from an IMS Health Canada database called the Therapy Dynamics database were analyzed. The database contains information about prescriptions filled at outpatient pharmacies in Canada, linked at the individual level over time periods as long as 36 months. Antidepressant prescriptions were used as a proxy indicator for depressive disorders. The frequency of antidepressant use was compared in cohorts treated with glatiramer acetate and interferon beta. RESULTS: No differences in the frequency of antidepressant treatment were observed. A large proportion (approximately 40%) in all treatment cohorts were treated with antidepressants at some time over the study interval. The proportions remained comparable after adjustment for age and sex and in a time-to-event analysis of new antidepressant prescriptions. Among patients receiving prescriptions exclusively from Neurologists, the frequency of exposure to antidepressants was much lower (2.4%). CONCLUSIONS: This analysis uncovered no evidence that antidepressant treatment occurs more often in people treated with interferon beta than in those treated with glatiramer acetate. These results help to confirm that depression is not associated with interferon beta treatment in MS.

Reliability of visual temporal thresholds.

BACKGROUND: Visual processing deficits involving temporal characteristics are typically not captured by the widely used outcome measures (i.e., Expanded Disability Status Scale, Multiple Sclerosis Functional Composite) in multiple sclerosis (MS). Visual temporal thresholds (i.e., measurements of the temporal aspects in visual processing) are typically significantly higher (i.e., prolonged) in MS patients when compared to controls. The test-retest reliability of these thresholds was examined in patients with MS. METHODS: Visual temporal thresholds were measured in 21 stable MS patients during two separate test sessions. Test-retest reliability and the standard error of measurement were calculated. The threshold of change in visual temporal thresholds in MS patients that would correspond to real change beyond measurement error with 95% certainty was also calculated. For comparisons, a control group (n = 10) was included. RESULTS: The test-retest reliability of this measure of visual temporal thresholds was 0.97. The threshold indicating change beyond chance or measurement error with 95% certainty was 11 ms. Higher thresholds were significantly correlated with longer durations of disease. CONCLUSIONS: This measure of visual temporal thresholds has excellent test-retest reliability and a change of greater than 11 ms is highly likely to represent real change in MS patients. The findings indicate that these measurements may provide useful clinical information about functional changes regarding the temporal aspects of the visual system, which is currently not captured by the Extended Disability Status Scale.

Experimental models of neuroprotection relevant to multiple sclerosis.

Activated T cells, particularly those of the T-helper (Th) 1 subset, have the capacity to kill neurons. Strategies for preventing such damage may include deviation of activated T cells into the Th2 subset (e.g., via use of glatiramer acetate), alteration of functional properties of Th1 cells (e.g., through use of interferon [INF]-beta or IV immunoglobulin), and inhibition of activated cell migration into the CNS (e.g., by employing INF-beta or natalizumab). Matrix metalloproteinase-9 (MMP-9) also causes neuron death in neurotoxicity models, and examination of medications with MMP inhibitory activity indicates that minocycline is capable of preventing such damage. Minocycline also has other properties relevant to conferring neuroprotection, such as inhibition of microglial activity and apoptosis pathways. In a small pilot study in patients with relapsing-remitting multiple sclerosis, minocycline treatment produced favorable outcomes in terms of gadolinium-enhancing lesions and clinical course. Further studies are needed to establish whether experimental neuroprotection strategies involving these mechanisms may be translated into preventing neurodegeneration in multiple sclerosis.

Deep grey matter "black T2" on 3 tesla magnetic resonance imaging correlates with disability in multiple sclerosis.

T2 hypointensity (black T2, BT2) in the deep grey matter of multiple sclerosis (MS) patients correlate weakly with disability at 1.5 T. BT2 is likely to be caused by abnormal iron deposition. We compared the correlation between disability and deep grey matter BT2 measured on 3 T MRI and on 1.5 T MRI in 17 MS patients. We observed a significant correlation between expanded disability status scale and signal intensity on 3 T MRI in the globus pallidus and the caudate nucleus (r = -0.5, P < 0.05). BT2 at 3 T may be a useful MRI measure associated with disability in MS and warrants further study.

The clinical response to minocycline in multiple sclerosis is accompanied by beneficial immune changes: a pilot study.

Minocycline has immunomodulatory and neuroprotective activities in vitro and in an animal model of multiple sclerosis (MS). We have previously reported that minocycline decreased gadolinium-enhancing activity over six months in a small trial of patients with active relapsing-remitting MS (RRMS). Here we report the impact of oral minocycline on clinical and magnetic resonance imaging (MRI) outcomes and serum immune molecules in this cohort over 24 months of open-label minocycline treatment. Despite a moderately high pretreatment annualized relapse rate (1.3/year pre-enrolment; 1.2/year during a three-month baseline period) prior to treatment, no relapses occurred between months 6 and 24. Also, despite very active MRI activity pretreatment (19/40 scans had gadolinium-enhancing activity during a three-month run-in), the only patient with gadolinium-enhancing lesions on MRI at 12 and 24 months was on half-dose minocycline. Levels of the p40 subunit of interleukin (IL)-12, which at high levels might antagonize the proinflammatory IL-12 receptor, were elevated over 18 months of treatment, as were levels of soluble vascular cell adhesion molecule-1. The activity of matrix metalloproteinase-9 was decreased by treatment. Thus, clinical and MRI outcomes are supported by systemic immunological changes and call for further investigation of minocycline in MS.

Identifying reliable change in tactile temporal thresholds in multiple sclerosis: test-retest reliability.

BACKGROUND: Tactile temporal thresholds are typically significantly higher (ie, prolonged) in multiple sclerosis (MS) patients when compared to controls and increase significantly during relapses, probably reflecting integrity of conduction across a portion of the corpus callosum. As part of an ongoing validation study of tactile temporal thresholds, the test-retest reliability of these thresholds was examined in patients with MS. METHODS: Tactile temporal thresholds were measured in 61 MS patients during two separate test sessions within three weeks. Test-retest reliability and the standard error of measurement were calculated. The threshold of change in tactile temporal thresholds in MS patients that would correspond to real change beyond measurement error with 95% certainty was also calculated. RESULTS: The test-retest reliability of this measure of tactile temporal thresholds was 0.93. The threshold indicating change beyond chance or measurement error with 95% certainty was 19 ms. CONCLUSIONS: This measure of tactile temporal thresholds has excellent test-retest reliability and a change of greater than 19 ms is highly likely to represent real change. This measure is promising as a precise, reliable outcome measure in MS.

Tactile temporal thresholds detect relapse-related changes in multiple sclerosis: a preliminary study.

BACKGROUND: Tactile temporal thresholds, which represent the time separating the onset of two tactile stimuli when they are judged as simultaneous, can differentiate a group of people with multiple sclerosis (MS) from normal controls. Demyelination, axonal injury and loss, and altered information processing all occur in MS and may cause these increased thresholds. Thus, tactile temporal thresholds may be a useful outcome measure in MS. Our objective was to assess whether tactile temporal thresholds reflect change during a MS relapse. METHODS: During a study to evaluate the stability of tactile temporal thresholds in people with MS, two participants suffered relapses. Both events were associated with prolonged thresholds (i.e., significantly increased thresholds). CONCLUSIONS: Tactile temporal thresholds can detect neurologic worsening and thus warrant further evaluation as a useful method to facilitate in the monitoring of disease change in people with MS.

A comparison of health utility measures for the evaluation of multiple sclerosis treatments.

OBJECTIVES: To evaluate the practical application and psychometric properties of three health utility measures in a sample of MS patients with a broad range of neurological disability as measured by the Extended Disability Status Scale (EDSS). METHODS: Patients randomly selected from two MS clinic registries were assessed using standard clinical methods and completed three generic measures of health utility (EQ-5D, HUI Mark III, SF-6D). The proportion of missing data, test/retest reliability, and construct validity of each health utility measure were examined. RESULTS: The assessments were completed by 187 patients. Less than 10% of data were missing for the subscales of the SF-6D (< 3.2%), HUI Mark III (<1.6%), and EQ-5D (< or =7.5%). Severely disabled patients were more likely to omit physical function questions for the SF-6D (20%), and EQ-5D (43%). Retest reliability for the SF-6D (ICC = 0.83), EQ-5D (ICC = 0.81), and HUI Mark III (ICC = 0.87) were adequate for population surveys. Correlations between assessment of clinical function and each health utility measure were strongest for the HUI Mark III (HUI Mark III EDSS rho = -0.77, HUI Mark III ambulation index rho = -0.76, HUI Mark III timed 25 foot walk rho = -0.73, HUI Mark III nine hole peg test rho = -0.65). CONCLUSIONS: The health utility measures were generally feasible and reliable but the HUI Mark III demonstrated highest concordance with the EDSS across the full range of neurological disability. Of the three measures studied, the HUI Mark III may be the most appropriate for cost effectiveness evaluations of MS therapies.

The bioavailability of IV methylprednisolone and oral prednisone in multiple sclerosis.

Oral prednisone (1)might be a convenient, inexpensive alternative to IV methylprednisolone (IVMP) if the bioequivalent dose was known. We compared the total amount of steroid absorbed after 1250 mg oral prednisone vs 1 gram IVMP in 16 patients with multiple sclerosis (MS). At 24 hours, the mean area under the concentration-time curve (AUC), the main component of bioavailability, did not differ between groups (p = 0.122). This suggests that the amount of absorbed corticosteroid is similar after either steroid at these doses.

The effect of immunomodulatory treatment on multiple sclerosis fatigue.

OBJECTIVE: To assess the effects of glatiramer acetate and beta interferon on fatigue in multiple sclerosis. METHODS: Fatigue was measured at baseline and six months using the fatigue impact scale (FIS). Groups (glatiramer acetate and beta interferon) were evaluated for the proportion improved, using Fisher's exact test. Logistic regression analysis assessed the relation between treatment group and improvement and controlled for confounding variables. RESULTS: Six month paired FIS assessments were available for 218 patients (76% female). Ages ranged between 19 and 61 years, with 86% having relapsing-remitting disease. Glatiramer acetate was used by 61% and beta interferon by 39%. At baseline, total FIS and subscale scores were comparable in the two groups. More patients improved on glatiramer acetate than on beta interferon on total FIS (24.8% v 12.9%, p = 0.033; adjusted odds ratio = 2.36, 95% confidence interval 1.03 to 5.42), and on physical (28.6% v 14.1%, p = 0.013) and cognitive subscales (21.1% v 10.6%, p = 0.045). Logistic regression analysis confirmed the association between glatiramer acetate use and improved fatigue, after accounting for baseline group differences. CONCLUSIONS: The odds of reduced multiple sclerosis fatigue were around twice as great with glatiramer acetate treatment as with beta interferon. Confirmation of this result is required.

Major depression in multiple sclerosis: a population-based perspective.

OBJECTIVE: To determine the prevalence of major depression in multiple sclerosis (MS) in a population-based sample controlling for nonspecific illness effects. METHODS: This study used data from a large-scale national survey conducted in Canada: the Canadian Community Health Survey (CCHS). The analysis included 115,071 CCHS subjects who were 18 years or older at the time of data collection. The CCHS interview obtained self-reported diagnoses of MS and employed a brief predictive interview for major depression: the Composite International Diagnostic Interview Short Form for Major Depression. The 12-month period prevalence of major depression was estimated in subjects with and without MS and with and without other long-term medical conditions. RESULTS: The prevalence of major depression was elevated in persons with MS relative to those without MS and those reporting other conditions. The association persisted after adjustment for age and sex (adjusted odds ratio = 2.3, 95% CI 1.6 to 3.3). Major depression prevalence in MS for those in the 18- to 45-year age range was high at 25.7% (95% CI 15.6 to 35.7). CONCLUSIONS: The prevalence of major depression in the population with MS is elevated. This elevation is not an artifact of selection bias and exceeds that associated with having one or more other long-term conditions.