Clinical relevance of brain volume measures in multiple sclerosis

A serial 10-year follow-up study of brain atrophy and disability progression in RRMS patients

BACKGROUND

We explored the evolution of brain atrophy in relation to development of confirmed disability progression (CDP) on serial 1.5T magnetic resonance imaging (MRI) scans over a 10-year period in 181 patients with early relapsing-remitting multiple sclerosis (RRMS).

METHODS

At 10-year follow-up, they were divided into those with (100) or without (76) CDP (confirmed after 48 weeks). Changes in whole brain (WB), cortical, gray matter (GM), white matter, and ventricular cerebrospinal fluid (vCSF) volumes were calculated on three-dimensional T1-weighted (3D-T1) scans between all available time points.

RESULTS

In multiple sclerosis (MS) patients with CDP compared to those without, the greatest effect size percentage volume change from baseline to follow-up was detected for WB (d = 0.55, -7.5% vs -5.2%, p < 0.001), followed by vCSF (d = 0.51, +41.1% vs +25.7%, p < 0.001), cortical (d = 0.49, -7.7% vs -6.2%, p = 0.001), and GM (d = 0.40, -7.1% vs -5.8%, p = 0.006) volumes. Mixed-effects model analysis, adjusted for age, sex, and treatment change, showed significant interactions between CDP status and percentage changes for WB and vCSF (p < 0.001), cortical (p = 0.02), and GM (p = 0.04) volumes.

CONCLUSIONS

WB and cortical atrophy, and enlargement of vCSF spaces are associated with development of CDP on serial yearly MRI assessments over a period of 10 years.

The Direct Effects of Fingolimod in the Central Nervous System: Implications for Relapsing Multiple Sclerosis

Fingolimod, a structural analog of sphingosine derived from fungal metabolites, is a functional antagonist of the G-protein-coupled sphingosine 1-phosphate (S1P) receptors S1P(1,3,4,5). In the treatment of relapsing forms of multiple sclerosis (RMS), fingolimod acts by reversibly retaining central memory T cells and naïve T cells in lymph nodes, thereby reducing the recirculation of autoreactive lymphocytes to the central nervous system (CNS). Fingolimod also has differential effects on the trafficking and function of B-cell subtypes and natural killer (NK) cells in peripheral blood and the CNS. Fingolimod also crosses the blood-brain barrier (BBB) and accumulates in the CNS. Experimental evidence increasingly supports a direct action of fingolimod within the CNS on brain cells, providing protection against the neurodegenerative component of RMS. We review the direct influence of this compound on CNS pathogenesis in RMS, including the central effects of fingolimod in animal models of MS and on neural cell types that express S1P receptors, such as astrocytes, BBB endothelial cells, microglia, neurones, and oligodendrocytes, which are all involved in RMS pathology.

Onset of clinical and MRI efficacy occurs early after fingolimod treatment initiation in relapsing multiple sclerosis

To minimize the clinical burden associated with multiple sclerosis (MS), early control of focal and diffuse CNS disease activity is a treatment priority. A post hoc analysis was conducted to evaluate the onset of efficacy of fingolimod treatment in patients with relapsing MS. Data from patients who received fingolimod 0.5 mg or placebo during either of two 24-month, double-blind, randomized, parallel-group clinical trials (FREEDOMS and FREEDOMS II) were pooled for analysis. Efficacy outcomes were: time to first confirmed relapse; annualized relapse rate (ARR); proportions of patients free from T1 gadolinium-enhancing lesions or new/newly enlarged T2 lesions; percentage brain volume loss (BVL); and change in Multiple Sclerosis Functional Composite (MSFC) z-score from baseline to 6 months. An early benefit was seen with fingolimod (N = 783) vs. placebo (N = 773) for ARR at both 3 and 6 months (3 months, 0.32 vs. 0.52, p = 0.0015; 6 months, 0.21 vs. 0.45, p < 0.0001). Time to first relapse was also delayed with fingolimod vs. placebo from day 48 onwards. At 6 months, more patients in the fingolimod group than in the placebo group were free from new MRI activity (65.3 vs. 40.5%, p < 0.0001) and had less BVL (37.1% reduction vs. placebo, p < 0.001). MSFC z-score favored fingolimod over placebo at 6 months, with improvements noted in 9-Hole Peg Test and Paced Auditory Serial Addition Test scores. Improvements in outcomes related to relapses, MRI, disability, cognition, and BVL occurred within 6 months of treatment initiation with fingolimod.

Establishing pathological cut-offs of brain atrophy rates in multiple sclerosis

OBJECTIVE

To assess whether it is feasible to establish specific cut-off values able to discriminate 'physiological' or 'pathological' brain volume rates in patients with multiple sclerosis (MS).

METHODS

The study was based on the analysis of longitudinal MRI data sets of patients with MS (n=206, 87% relapsing-remitting, 7% secondary progressive and 6% primary progressive) and healthy controls (HC; n=35). Brain atrophy rates were computed over a mean follow-up of 7.5 years (range 1-12) for patients with MS and 6.3 years (range 1-12.5) for HC with the SIENA software and expressed as annualised per cent brain volume change (PBVC/y). A weighted (on the follow-up length) receiver operating characteristic analysis and the area under the curve (AUC) were used for statistics.

RESULTS

The weighted PBVC/y was -0.51±0.27% in patients with MS and -0.27±0.15% in HC (p<0.0001). There was a significant age-related difference in PBVC/y between HC older and younger than 35 years of age (p=0.02), but not in patients with MS (p=0.8). The cut-off of PBVC/y, as measured by SIENA that could maximise the accuracy in discriminating patients with MS from HC, was -0.37%, with 67% sensitivity and 80% specificity. According to the observed distribution, values of PBVC/y as measured by SIENA that could define a pathological range were above -0.52% with 95% specificity, above -0.46% with 90% specificity and above -0.40% with 80% specificity.

CONCLUSIONS

Our evidence-based criteria provide values able to discriminate the presence or absence of 'pathological' brain volume loss in MS with high specificity. Such results could be of great value in a clinical setting, particularly in assessing treatment efficacy in MS.

Optimizing treatment success in multiple sclerosis

Despite important advances in the treatment of multiple sclerosis (MS) over recent years, the introduction of several disease-modifying therapies (DMTs), the burden of progressive disability and premature mortality associated with the condition remains substantial. This burden, together with the high healthcare and societal costs associated with MS, creates a compelling case for early treatment optimization with highly efficacious therapies. Often, patients receive several first-line therapies, while more recent and in part more effective treatments are still being introduced only after these have failed. However, with the availability of highly efficacious therapies, a novel treatment strategy has emerged, where the aim is to achieve no evidence of disease activity (NEDA). Achieving NEDA necessitates regular monitoring of relapses, disability and functionality. However, there is only a poor correlation between conventional magnetic resonance imaging measures like T2 hyperintense lesion burden and the level of clinical disability. Hence, MRI-based measures of brain atrophy have emerged in recent years potentially reflecting the magnitude of MS-related neuroaxonal damage. Currently available DMTs differ markedly in their effects on brain atrophy: some, such as fingolimod, have been shown to significantly slow brain volume loss, compared to placebo, whereas others have shown either no, inconsistent, or delayed effects. In addition to regular monitoring, treatment optimization also requires early intervention with efficacious therapies, because accumulating evidence shows that effective intervention during a limited period early in the course of MS is critical for maintaining neurological function and preventing subsequent disability. Together, the advent of new MS therapies and evolving management strategies offer exciting new opportunities to optimize treatment outcomes.

Amyloid PET imaging in multiple sclerosis: an (18)F-florbetaben study

Background

Positron emission tomography (PET) images with amyloid tracers show normal uptake in healthy white matter, which suggests that amyloid tracers are potentially useful for studying such white matter diseases as multiple sclerosis (MS).

Methods

Twelve patients diagnosed with MS (5 with RRMS, 5 with SPMS, and 2 with PPMS) and 3 healthy controls underwent studies with MRI and ¹⁸F-florbetaben-PET imaging. Images were preprocessed using Statistical Parametric Mapping software. We analysed ¹⁸F-florbetaben uptake in demyelinating plaques (appearing as hyperintense lesions in FLAIR sequences), in normal-appearing white matter, and in grey matter.

Results

Mean standardized uptake value relative to cerebellum was higher in normally appearing white matter (NAWM) (1.51 ± 0.12) than in damaged white matter (DWM) (1.24 ± 0.12; P = .002). Mean percentage of change between NAWM and DWM was −17.56 % ± 6.22 %. This percentage of change correlated negatively with EDSS scores (r = −0.61, p < .05) and with age (r = −0.83, p < 0.01). Progressive forms of MS showed a more pronounced reduction of the uptake in DWM in comparison to relapsing-remitting form.

Conclusions

Uptake of ¹⁸F-florbetaben in damaged white matter is lower than that occurring in normally-appearing white matter. These findings indicate that amyloid tracers may be useful in studies of MS, although further research is needed to evaluate the utility of amyloid-PET in monitoring MS progression.

Electronic supplementary material

The online version of this article (doi:10.1186/s12883-015-0502-2) contains supplementary material, which is available to authorized users.

Inclusion of brain volume loss in a revised measure of 'no evidence of disease activity' (NEDA-4) in relapsing-remitting multiple sclerosis

Background:

‘No evidence of disease activity’ (NEDA), defined as absence of magnetic resonance imaging activity (T2 and/or gadolinium-enhanced T1 lesions), relapses and disability progression (‘NEDA-3’), is used as a comprehensive measure of treatment response in relapsing multiple sclerosis (RMS), but is weighted towards inflammatory activity. Accelerated brain volume loss (BVL) occurs in RMS and is an objective measure of disease worsening and progression.

Objective:

To assess the contribution of individual components of NEDA-3 and the impact of adding BVL to NEDA-3 (‘NEDA-4’)

Methods:

We analysed data pooled from two placebo-controlled phase 3 fingolimod trials in RMS and assessed NEDA-4 using different annual BVL mean rate thresholds (0.2%–1.2%).

Results:

At 2 years, 31.0% (217/700) of patients receiving fingolimod 0.5 mg achieved NEDA-3 versus 9.9% (71/715) on placebo (odds ratio (OR) 4.07; p < 0.0001). Adding BVL (threshold of 0.4%), the respective proportions of patients achieving NEDA-4 were 19.7% (139/706) and 5.3% (38/721; OR 4.41; p < 0.0001). NEDA-4 status favoured fingolimod across all BVL thresholds tested (OR 4.01–4.41; p < 0.0001).

Conclusion:

NEDA-4 has the potential to capture the impact of therapies on both inflammation and neurodegeneration, and deserves further evaluation across different compounds and in long-term studies.

The relationship between the rate of brain volume loss during first 24 months and disability progression over 24 and 48 months in relapsing MS

Clinical evidence in patients with relapsing-remitting multiple sclerosis suggests an association between MRI outcome measures and disability progression (DP). Post hoc analysis to investigate the association and potential predictive value of brain volume loss (BVL) with long-term DP in FREEDOMS. Patients were categorized into quartiles by SIENA-calculated percent brain volume change from baseline to month (M) 24. Patient characteristics at baseline were determined for each quartile, as were the proportions of patients at M24 and M48 reaching Expanded Disability Status Scale (EDSS) scores of ≥4.0 or ≥6.0 or DP confirmed at 3 months (CDP3) or 6 months (CDP6), and change in EDSS and Multiple Sclerosis Functional Composite. MS disease activity and severity as well as brain volume at baseline were predictive of subsequent BVL over 24 months. The quartiles of patients with greater BVL at 24 months were at highest risk (odds ratio, p value) for reaching EDSS ≥4 (2.8, p = 0.001) or ≥6 (5.73, p = 0.0005) and experienced more DP at M24 (CDP3 2.13, p = 0.002; CDP6 2.17, p = 0.003) and M48 (CDP3 1.98, p = 0.006; CDP6 1.87, p = 0.018) compared to the quartile of patients with the least amount of BVL. These findings confirm the clinical relevance of early brain volume changes for long-term DP.

Immunological and short-term brain volume changes in relapsing forms of multiple sclerosis treated with interferon beta-1a subcutaneously three times weekly: an open-label two-arm trial

Background

Brain volume atrophy is observed in relapsing–remitting multiple sclerosis (RRMS).

Methods

Brain volume changes were evaluated in 23 patients with RRMS treated with interferon β-1a 44 μg given subcutaneously (SC) three times a week (tiw) and 15 healthy controls. Percentages of whole brain and tissue-specific volume change were measured from baseline (0 months) to 3 months, from 3 to 6 months, and from baseline to 6 months using SIENAX Multi Time Point (SX-MTP) algorithms. Immunological status of patients was also determined and correlations between subsets of T cells and changes in brain volume were assessed.

Results

Interferon β-1a 44 μg SC tiw in 23 patients with RRMS resulted in significant reductions in whole brain and gray matter tissue volume early in the treatment course (baseline to 3 months; mean change; –0.95 %; P = 0.030, –1.52 %; P = 0.004, respectively), suggesting a short-term treatment-induced pseudoatrophy effect. From baseline to 6 months, there were significant correlations observed between decreased T- cell expression of IL-17 F and decreased whole brain and brain tissue-specific volume.

Conclusions

These findings are consistent with the interpretation of the pseudoatrophy effect as resolution of inflammation following treatment initiation with interferon β-1a 44 μg SC tiw, rather than disease-related tissue loss.

Trial registration

ClinicalTrials.gov; NCT01085318

The effect of disease-modifying therapies on brain atrophy in patients with clinically isolated syndrome: a systematic review and meta-analysis

OBJECTIVES

Brain atrophy is associated with cognitive deficits in patients with clinically isolated syndrome (CIS) and can predict conversion to clinical definite multiple sclerosis. The aim of the present meta-analysis was to evaluate the effect of disease-modifying drugs (DMDs) on brain atrophy in patients with CIS.

METHODS

Eligible placebo-control randomized clinical trials of patients with CIS that had reported changes in brain volume during the study period were identified by searching the MEDLINE, SCOPUS, and Cochrane Central Register of Controlled Trials (CENTRAL) databases. This meta-analysis adopted the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines for systematic reviews and meta-analyses.

RESULTS

Three eligible studies were identified, comprising 1362 patients. The mean percentage change in brain volume was found to be significantly lower in DMD-treated patients versus placebo-treated subgroups (standardized mean difference [SMD]: = -0.13, 95% confidence interval [CI]: -0.25, 0.01; p = 0.04). In the subgroup analysis of the two studies that provided data on brain-volume changes for the first (0-12 months) and second (13-24 months) year of treatment, DMD attenuated brain-volume loss in comparison with placebo during the second year (SMD = -0.25; 95% CI: -0.43, -0.07; p < 0.001), but not during the first year of treatment (SMD = -0.01; 95% CI: -0.27, 0.24; p = 0.93). No evidence of heterogeneity was found between estimates, while funnel-plot inspection revealed no evidence of publication bias.

CONCLUSIONS

DMDs appear to attenuate brain atrophy over time in patients with CIS. The effect of DMDs on brain-volume loss is evident after the first year of treatment.

Evidence-based guidelines: MAGNIMS consensus guidelines on the use of MRI in multiple sclerosis--establishing disease prognosis and monitoring patients

The role of MRI in the assessment of multiple sclerosis (MS) goes far beyond the diagnostic process. MRI techniques can be used as regular monitoring to help stage patients with MS and measure disease progression. MRI can also be used to measure lesion burden, thus providing useful information for the prediction of long-term disability. With the introduction of a new generation of immunomodulatory and/or immunosuppressive drugs for the treatment of MS, MRI also makes an important contribution to the monitoring of treatment, and can be used to determine baseline tissue damage and detect subsequent repair. This use of MRI can help predict treatment response and assess the efficacy and safety of new therapies. In the second part of the MAGNIMS (Magnetic Resonance Imaging in MS) network's guidelines on the use of MRI in MS, we focus on the implementation of this technique in prognostic and monitoring tasks. We present recommendations on how and when to use MRI for disease monitoring, and discuss some promising MRI approaches that may be introduced into clinical practice in the near future.

Motor network efficiency and disability in multiple sclerosis

OBJECTIVE

To develop a composite MRI-based measure of motor network integrity, and determine if it explains disability better than conventional MRI measures in patients with multiple sclerosis (MS).

METHODS

Tract density imaging and constrained spherical deconvolution tractography were used to identify motor network connections in 22 controls. Fractional anisotropy (FA), magnetization transfer ratio (MTR), and normalized volume were computed in each tract in 71 people with relapse onset MS. Principal component analysis was used to distill the FA, MTR, and tract volume data into a single metric for each tract, which in turn was used to compute a composite measure of motor network efficiency (composite NE) using graph theory. Associations were investigated between the Expanded Disability Status Scale (EDSS) and the following MRI measures: composite motor NE, NE calculated using FA alone, FA averaged in the combined motor network tracts, brain T2 lesion volume, brain parenchymal fraction, normal-appearing white matter MTR, and cervical cord cross-sectional area.

RESULTS

In univariable analysis, composite motor NE explained 58% of the variation in EDSS in the whole MS group, more than twice that of the other MRI measures investigated. In a multivariable regression model, only composite NE and disease duration were independently associated with EDSS.

CONCLUSIONS

A composite MRI measure of motor NE was able to predict disability substantially better than conventional non-network-based MRI measures.

The neuronal component of gray matter damage in multiple sclerosis: A [(11) C]flumazenil positron emission tomography study

OBJECTIVE

Using positron emission tomography (PET) with [(11) C]flumazenil ([(11) C]FMZ), an antagonist of the central benzodiazepine site located within the GABAA receptor, we quantified and mapped neuronal damage in the gray matter (GM) of patients with multiple sclerosis (MS) at distinct disease stages. We investigated the relationship between neuronal damage and white matter (WM) lesions and evaluated the clinical relevance of this neuronal PET metric.

METHODS

A cohort of 18 MS patients (9 progressive and 9 relapsing-remitting) was compared to healthy controls and underwent neurological and cognitive evaluations, high-resolution dynamic [(11) C]FMZ PET imaging and brain magnetic resonance imaging. [(11) C]FMZ binding was estimated using the partial saturation protocol providing voxel-wise absolute quantification of GABAA receptor concentration. PET data were evaluated using a region of interest (ROI) approach as well as on a vertex-by-vertex basis.

RESULTS

[(11) C]FMZ binding was significantly decreased in the cortical GM of MS patients, compared to controls (-10%). Cortical mapping of benzodiazepine receptor concentration ([(11) C]FMZ Bmax) revealed significant intergroup differences in the bilateral parietal cortices and right frontal areas. ROI analyses taking into account GM volume changes showed extensive decrease in [(11) C]FMZ binding in bilateral parietal, cingulate, and insular cortices as well as in the thalami, amygdalae, and hippocampi. These changes were significant in both progressive and relapsing-remitting forms of the disease and correlated with WM T2-weighted lesion load. [(11) C]FMZ cortical binding correlated with cognitive performance.

INTERPRETATION

This pilot study showed that PET with [(11) C]FMZ could be a promising and sensitive quantitative marker to assess and map the neuronal substrate of GM pathology in MS.

A Longitudinal Study of Disability, Cognition and Gray Matter Atrophy in Early Multiple Sclerosis Patients According to Evidence of Disease Activity

New treatment options may make “no evidence of disease activity” (NEDA: no relapses or disability progression and no new/enlarging MRI lesions, as opposed to “evidence of disease activity” (EDA) with at least one of the former), an achievable goal in relapsing-remitting multiple sclerosis (RRMS). The objective of the present study was to determine whether early RRMS patients with EDA at one-year follow-up had different disability, cognition, treatment and gray matter (GM) atrophy rates from NEDA patients and healthy controls (HC). RRMS patients (mean age 34 years, mean disease duration 2.2 years) were examined at baseline and one-year follow-up with neurological (n = 72), neuropsychological (n = 56) and structural MRI (n = 57) examinations. Matched HC (n = 61) were retested after three years. EDA was found in 46% of RRMS patients at follow-up. EDA patients used more first line and less second line disease modifying treatment than NEDA (p = 0.004). While the patients groups had similar disability levels at baseline, they differed in disability at follow-up (p = 0.010); EDA patients progressed (EDSS: 1.8–2.2, p = 0.010), while NEDA patients improved (EDSS: 2.0–1.7, p<0.001). Cognitive function was stable in both patient groups. Subcortical GM atrophy rates were higher in EDA patients than HC (p<0.001). These results support the relevance of NEDA as outcome in RRMS and indicate that pathological neurodegeneration in RRMS mainly occur in patients with evidence of disease activity.

Effect of intramuscular interferon beta-1a on gray matter atrophy in relapsing-remitting multiple sclerosis: A retrospective analysis

BACKGROUND

Changes in gray matter (GM) volume may be a useful measure of tissue loss in multiple sclerosis (MS).

OBJECTIVES

To investigate the rate, patterns, and disability correlates of GM volume change in an MS treatment clinical trial.

METHODS

Patients (n=140) with relapsing-remitting MS were randomized to intramuscular (IM) interferon (IFN) beta-1a or placebo. Treatment effects on GM fraction (GMF) and white matter (WM) fraction (WMF) changes, differences in rates of GMF and WMF change in year one and two on treatment, and differences in atrophy rates by disease progression status were assessed retrospectively.

RESULTS

Significantly less GM atrophy (during year two), but not WM atrophy (at any point), was observed with IM IFN beta-1a compared with placebo. Pseudoatrophy effects were more apparent in WM than in GM; in year one, greater WM volume loss was observed with IM IFN beta-1a than with placebo, whereas GM volume loss was similar between groups. Risk of sustained disability progression was significantly associated with GM, but not WM, atrophy.

CONCLUSIONS

These results suggest that GMF change is more meaningful than WMF as a marker of tissue loss and may be useful to augment whole brain atrophy measurements in MS clinical trials.

MRI in the Diagnosis and Monitoring of Multiple Sclerosis: An Update

Magnetic resonance imaging (MRI) is the most powerful tool for the early (differential) diagnosis of multiple sclerosis (MS) and has been part of the International Panel criteria (2001, 2005, 2010) for more than 10 years. The role of brain and spinal cord MRI in the diagnosis of MS is well established. New MR techniques and markers will further improve the diagnostic value in a research and clinical routine setting. In addition to diagnosis, MRI is widely used for prognostic evaluation as well as treatment efficacy and safety monitoring. This field has gained importance with the introduction of new MS therapeutics. Therefore, the scope of MRI-guided MS disease monitoring has been widened to include rigorous treatment monitoring aiming at "no evidence of disease activity (NEDA)". Next, safety monitoring of treated MS patients has become major concern to enable early detection of opportunistic infections such as progressive multifocal leukoencephalopathy (PML). Driven by these new developments, recently published expert panel guidelines stressed the need for standardized imaging protocols and targeted specialized imaging markers for MS diagnosis and disease monitoring. This review article aims to give an update on the role of MRI in the diagnosis and monitoring of MS with particular emphasis to treatment efficacy and safety, both in clinical practice and in research.

Evidence-based guidelines: MAGNIMS consensus guidelines on the use of MRI in multiple sclerosis-clinical implementation in the diagnostic process

The clinical use of MRI in patients with multiple sclerosis (MS) has advanced markedly over the past few years. Technical improvements and continuously emerging data from clinical trials and observational studies have contributed to the enhanced performance of this tool for achieving a prompt diagnosis in patients with MS. The aim of this article is to provide guidelines for the implementation of MRI of the brain and spinal cord in the diagnosis of patients who are suspected of having MS. These guidelines are based on an extensive review of the recent literature, as well as on the personal experience of the members of the MAGNIMS (Magnetic Resonance Imaging in MS) network. We address the indications, timing, coverage, reporting and interpretation of MRI studies in patients with suspected MS. Our recommendations are intended to help radiologists and neurologists standardize and optimize the use of MRI in clinical practice for the diagnosis of MS.

Know your tools--concordance of different methods for measuring brain volume change after ischemic stroke

INTRODUCTION

Longitudinal brain volume changes have been investigated in a number of cerebral disorders as a surrogate marker of clinical outcome. In stroke, unique methodological challenges are posed by dynamic structural changes occurring after onset, particularly those relating to the infarct lesion. We aimed to evaluate agreement between different analysis methods for the measurement of post-stroke brain volume change, and to explore technical challenges inherent to these methods.

METHODS

Fifteen patients with anterior circulation stroke underwent magnetic resonance imaging within 1 week of onset and at 1 and 3 months. Whole-brain as well as grey- and white-matter volume were estimated separately using both an intensity-based and a surface watershed-based algorithm. In the case of the intensity-based algorithm, the analysis was also performed with and without exclusion of the infarct lesion. Due to the effects of peri-infarct edema at the baseline scan, longitudinal volume change was measured as percentage change between the 1 and 3-month scans. Intra-class and concordance correlation coefficients were used to assess agreement between the different analysis methods. Reduced major axis regression was used to inspect the nature of bias between measurements.

RESULTS

Overall agreement between methods was modest with strong disagreement between some techniques. Measurements were variably impacted by procedures performed to account for infarct lesions.

CONCLUSIONS

Improvements in volumetric methods and consensus between methodologies employed in different studies are necessary in order to increase the validity of conclusions derived from post-stroke cerebral volumetric studies. Readers should be aware of the potential impact of different methods on study conclusions.

The effect of disease modifying therapies on brain atrophy in patients with relapsing-remitting multiple sclerosis: a systematic review and meta-analysis

Background

The aim of the present meta-analysis was to evaluate the effect of disease-modifying drugs (DMD) on brain atrophy in patients with relapsing-remitting multiple sclerosis (RRMS) using available randomized-controlled trial (RCT) data.

Methods

We conducted a systematic review and meta-analysis according to PRISMA guidelines of all available RCTs of patients with RRMS that reported data on brain volume measurements during the study period.

Results

We identified 4 eligible studies, including a total of 1819 RRMS patients (71% women, mean age 36.5 years, mean baseline EDSS-score: 2.4). The mean percentage change in brain volume was found to be significantly lower in DMD versus placebo subgroup (standardized mean difference: -0.19; 95%CI: -0.27–-0.11; p<0.001). We detected no evidence of heterogeneity between estimates (I² = 30%, p = 0.19) nor publication bias in the Funnel plots. Sensitivity analyses stratifying studies according to brain atrophy neuroimaging protocol disclosed no evidence of heterogeneity (p = 0.16). In meta-regression analyses, the percentage change in brain volume was found to be inversely related with duration of observation period in both DMD (meta-regression slope = -0.03; 95% CI: -0.04–-0.02; p<0.001) and placebo subgroups (meta-regression slope = -0.05; 95% CI: -0.06–-0.04; p<0.001). However, the rate of percentage brain volume loss over time was greater in placebo than in DMD subgroup (p = 0.017, ANCOVA).

Conclusions

DMD appear to be effective in attenuating brain atrophy in comparison to placebo and their benefit in delaying the rate of brain volume loss increases linearly with longer treatment duration.

Correlation between brain volume loss and clinical and MRI outcomes in multiple sclerosis

OBJECTIVE

We investigated the determinants and clinical correlations of MRI-detected brain volume loss (BVL) among patients with relapsing-remitting multiple sclerosis from the phase 3 trials of fingolimod: FREEDOMS, FREEDOMS II, and TRANSFORMS.

METHODS

Post hoc analyses were conducted in the intent-to-treat populations from each trial and in a combined dataset of 3,635 patients from the trials and their extensions. The relationship between brain volume changes and demographic, clinical, and MRI parameters was studied in pairwise correlations (Pearson) and in multiple regression models. The relative frequency of confirmed disability progression was evaluated in the combined dataset by strata of concurrent BVL at up to 4 years.

RESULTS

Increasing age, disease duration, T2 lesion volume, T1-hypointense lesion volume, and disability were associated with reduced brain volume (p < 0.001, all). The strongest individual baseline predictors of on-study BVL were T2 lesion volume, gadolinium-enhancing lesion count, and T1-hypointense lesion volume (p < 0.01, all). During each study, BVL correlated most strongly with cumulative gadolinium-enhancing lesion count, new/enlarged T2 lesion count (p < 0.001, both), and number of confirmed on-study relapses (p < 0.01). Over 4 years in the combined dataset (mean exposure to study drug, 2.4 years), confirmed disability progression was most frequent in patients with greatest BVL.

CONCLUSIONS

Rate of BVL in patients during the fingolimod trials correlated with disease severity at baseline and new disease activity on study, and was associated with worsening disability.

Fingolimod effect on brain volume loss independently contributes to its effect on disability

Background:

Brain volume loss occurs in patients with relapsing–remitting MS. Fingolimod reduced brain volume loss in three phase 3 studies.

Objective:

To evaluate whether the effect of fingolimod on disability progression was mediated by its effects on MRI lesions, relapses or brain volume loss, and the extent of this effect.

Methods:

Patients (992/1272; 78%) from the FTY720 Research Evaluating Effects of Daily Oral Therapy in Multiple Sclerosis (FREEDOMS) study were analyzed. Month-24 percentage brain volume change, month-12 MRI-active lesions and relapse were assessed. The Prentice criteria were used to test surrogate marker validity. The proportion of treatment effect on disability progression explained by each marker was calculated.

Results:

Two-year disability progression was associated with active T2 lesions (OR = 1.24; p = 0.001) and more relapses during year 1 (OR = 2.90; p < 0.001) and lower percentage brain volume change over two years (OR = 0.78; p < 0.001). Treatment effect on active T2 lesions, relapses and percentage brain volume change explained 46%, 60% and 23% of the fingolimod effect on disability. Multivariate analysis showed the number of relapses during year 1 (OR = 2.62; p < 0.001) and yearly percentage brain volume change over two years (OR = 0.85; p = 0.009) were independent predictors of disability progression, together explaining 73% of fingolimod effect on disability.

Conclusions:

The treatment effect on relapses and, to a lesser extent, brain volume loss were both predictors of treatment effect on disability; combining these predictors better explained the effect on disability than either factor alone.

A randomized controlled phase II trial of riluzole in early multiple sclerosis

Objectives

We evaluated the effect of riluzole versus placebo added to weekly IM interferon beta-1a in early multiple sclerosis (MS).

Methods

This is a randomized (1:1), double-blind, placebo-controlled trial of riluzole 50 mg twice daily in subjects with MS onset less than 1 year prior. Trial participation was up to 3 years. The primary endpoint was change in percent brain volume change. Secondary endpoints included changes in normalized gray and normal-appearing white matter volumes, retinal nerve fiber layer thickness (RNFL), MS Functional Composite and Symbol Digit Modalities Test scores. Mixed model regression analysis was used to compare the changes over time between groups.

Results

Forty-three subjects were randomized to study drug (22 riluzole, 21 placebo). Baseline characteristics were overall similar between groups except for older age (P = 0.042), higher normalized cerebrospinal fluid volume (P = 0.050), lower normalized gray matter volume (P = 0.14), and thinner RNFL (P = 0.043) in the riluzole group. In the primary analysis, percent brain volume change in the placebo group decreased at a rate of 0.49% per year whereas the riluzole group decreased by 0.86% per year (0.37% more per year; 95% CI −0.78, 0.024; P = 0.065). Although age did not influence the rate of brain volume decline, the difference between groups was attenuated after adjustment for baseline normalized gray matter and lesion volume (0.26% more per year in riluzole group; 95% CI −0.057, 0.014; P = 0.22). Analyses of secondary outcomes showed no differences between groups.

Interpretation

This trial provides class 1 evidence that riluzole treatment does not meaningfully reduce brain atrophy progression in early MS.