Long-term clinical outcome of primary progressive MS: Predictive value of clinical and MRI data

Clinical impact of gender and age at onset on disease trajectory in primary progressive multiple sclerosis patients

BACKGROUND AND OBJECTIVES

Primary-progressive multiple sclerosis (PPMS) is characterized by gradual neurological deterioration without relapses. This study aimed to investigate the clinical impact of gender and age at disease onset on disease progression and disability accumulation in patients with this disease phenotype.

METHODS

Secondary data from the RelevarEM registry, a longitudinal database in Argentina, were analyzed. The cohort comprised patients with PPMS who met inclusion criteria. Statistical analysis with multilevel Bayesian robust regression modeling was conducted to assess the associations between gender, age at onset, and Expanded Disability Status Scale (EDSS) score trajectories.

RESULTS

We identified 125 patients with a confirmed diagnosis of PPMS encompassing a total of 464 observations. We found no significant differences in EDSS scores after 10 years of disease progression between genders (-0.08; credible interval (CI): -0.60, 0.42). A 20-year difference in age at onset did not show significant differences in EDSS score after 10 years of disease progression (0.281; CI: -0.251, 0.814). Finally, we also did not find any clinically relevant difference between gender EDSS score with a difference of 20 years in age at onset (-0.021; CI: -0.371, 0.319).

CONCLUSION

Biological plausibility of gender and age effects does not correlate with clinical impact measured by EDSS score.

Understanding the spectrum of non-motor symptoms in multiple sclerosis: insights from animal models

Multiple sclerosis is a chronic autoimmune disease of the central nervous system and is generally considered to be a non-traumatic, physically debilitating neurological disorder. In addition to experiencing motor disability, patients with multiple sclerosis also experience a variety of non-motor symptoms, including cognitive deficits, anxiety, depression, sensory impairments, and pain. However, the pathogenesis and treatment of such non-motor symptoms in multiple sclerosis are still under research. Preclinical studies for multiple sclerosis benefit from the use of disease-appropriate animal models, including experimental autoimmune encephalomyelitis. Prior to understanding the pathophysiology and developing treatments for non-motor symptoms, it is critical to characterize the animal model in terms of its ability to replicate certain non-motor features of multiple sclerosis. As such, no single animal model can mimic the entire spectrum of symptoms. This review focuses on the non-motor symptoms that have been investigated in animal models of multiple sclerosis as well as possible underlying mechanisms. Further, we highlighted gaps in the literature to explain the non-motor aspects of multiple sclerosis in experimental animal models, which will serve as the basis for future studies.

Spinal cord lesions and brain grey matter atrophy independently predict clinical worsening in definite multiple sclerosis: a 5-year, multicentre study

OBJECTIVES

To evaluate the combined contribution of brain and cervical cord damage in predicting 5-year clinical worsening in a multicentre cohort of definite multiple sclerosis (MS) patients.

METHODS

Baseline 3.0T brain and cervical cord T2-weighted and three-dimensional T1-weighted MRI was acquired in 367 patients with MS (326 relapse-onset and 41 progressive-onset) and 179 healthy controls. Expanded Disability Status Scale (EDSS) score was obtained at baseline and after a median follow-up of 5.1 years (IQR=4.8-5.2). At follow-up, patients were classified as clinically stable/worsened according to EDSS changes. Generalised linear mixed models identified predictors of clinical worsening, evolution to secondary progressive (SP) MS and reaching EDSS=3.0, 4.0 and 6.0 milestones at 5 years.

RESULTS

At follow-up, 120/367 (33%) patients with MS worsened clinically; 36/256 (14%) patients with relapsing-remitting evolved to SPMS. Baseline predictors of EDSS worsening were progressive-onset versus relapse-onset MS (standardised beta (β)=0.97), higher EDSS (β=0.41), higher cord lesion number (β=0.41), lower normalised cortical volume (β=-0.15) and lower cord area (β=-0.28) (C-index=0.81). Older age (β=0.86), higher EDSS (β=1.40) and cord lesion number (β=0.87) independently predicted SPMS conversion (C-index=0.91). Predictors of reaching EDSS=3.0 after 5 years were higher baseline EDSS (β=1.49), cord lesion number (β=1.02) and lower normalised cortical volume (β=-0.56) (C-index=0.88). Baseline age (β=0.30), higher EDSS (β=2.03), higher cord lesion number (β=0.66) and lower cord area (β=-0.41) predicted EDSS=4.0 (C-index=0.92). Finally, higher baseline EDSS (β=1.87) and cord lesion number (β=0.54) predicted EDSS=6.0 (C-index=0.91).

CONCLUSIONS

Spinal cord damage and, to a lesser extent, cortical volume loss helped predicting worse 5-year clinical outcomes in MS.

Smouldering multiple sclerosis: the ‘real MS’

Using a philosophical approach or deductive reasoning, we challenge the dominant clinico-radiological worldview that defines multiple sclerosis (MS) as a focal inflammatory disease of the central nervous system (CNS). We provide a range of evidence to argue that the ‘real MS’ is in fact driven primarily by a smouldering pathological disease process. In natural history studies and clinical trials, relapses and focal activity revealed by magnetic resonance imaging (MRI) in MS patients on placebo or on disease-modifying therapies (DMTs) were found to be poor predictors of long-term disease evolution and were dissociated from disability outcomes. In addition, the progressive accumulation of disability in MS can occur independently of relapse activity from early in the disease course. This scenario is underpinned by a more diffuse smouldering pathological process that may affect the entire CNS. Many putative pathological drivers of smouldering MS can be potentially modified by specific therapeutic strategies, an approach that may have major implications for the management of MS patients. We hypothesise that therapeutically targeting a state of ‘no evident inflammatory disease activity’ (NEIDA) cannot sufficiently prevent disability accumulation in MS, meaning that treatment should also focus on other brain and spinal cord pathological processes contributing to the slow loss of neurological function. This should also be complemented with a holistic approach to the management of other systemic disease processes that have been shown to worsen MS outcomes.

Evaluation of the times of disability progression and related factors in patients with primary progressive multiple sclerosis from Argentina

Background PPMS (primary progressive multiple sclerosis) patients represent less than 10% of MS patients in Argentina, men and women were similarly affected and most of them had a severe functional impairment. More rapid progression has been reported in males, but this is not the case in all datasets. The main objective of our study was to determine the time to EDSS (Expanded disability Status Scale) 4, 6 and 7 in PPMS patients. We also compared the times to reach these EDSS in men and women and aimed to identify factors associated with the disability progression. Method This cohort of patients with diagnosis of PPMS (n = 253) was selected from follow-up recorded in the RelevarEM registry database. Result The median times to EDSS 4, 6 and 7 were 24 (IQR 12-48), 72 (IQR 36-96) and 96 (IQR 60-120) months, respectively. Comparison of the survival curves to EDSS 4, 6 and 7 according to gender did not show significant differences (p = 0.33, p = 0.55 and p = 0.59). There is no evidence of an association between the clinical adjustment variables (sex, age >40 years at diagnosis, EDSS > 3 at onset and multifocal MS symptoms at disease onset) and the time of arrival at the EDSS 4, 6 and 7. Conclusion Severe disability was observed six years after the onset of symptoms. No association was found between the studied factors and the time to arrival to severe disability.

Definitions of primary-progressive multiple sclerosis trajectories by rate of clinical disability progression

BACKGROUND

Patients with primary progressive multiple sclerosis (PPMS) vary in the rate of disability progression.

OBJECTIVE

To classify clinical disability trajectories by rate of disability progression and evaluate predictive variables in PPMS patients.

METHODS

We analyzed the cumulative incidence of progression to disability and in accordance defined clinical PPMS disability trajectories. Correlation was performed with age, gender and disability at first presentation. Estimated onset was calculated and validated by the mathematical slope of disability progression.

RESULTS

The cohort included 304 PPMS patients, 146 (48%) were females, the mean age at first visit was 41.1 years, and the median follow up was 18.9 years. Median time to reach moderate and severe disability was 4.5 years (95%CI 3.8-5.2) and 12.6 years (95%CI 10.1-14.2), respectively. Extremely fast patients (3.3%) progressed to severe disability within 2-years, while very slow patients (4.7%) did not progress to moderate disability even 20 years after first presentation. Age and gender were not associated with progression. Moderate disability at first visit was associated with faster progression to severe disability. Mean estimated range of disease onset was between 4.3 to 9.9 years prior to first presentation.

CONCLUSIONS

Majority of PPMS patients progressed to moderate disability within 5-years and to severe disability within 15-years from first presentation. Clinical disability progression trajectories can help treatment-related decisions.

Adding brain volume measures into response criteria in multiple sclerosis: the Río-4 score

PURPOSE

Brain volume changes (BVC) on therapy in MS are being considered as predictor for treatment response at an individual level. We ought to assess whether adding BVC as a factor to monitor interferon-beta response improves the predictive ability of the (no) evidence of disease activity (EDA-3) and Río score (RS-3) criteria for confirmed disability progression in a historical cohort.

METHODS

One hundred one patients from an observational cohort treated with interferon-beta were assessed for different cutoff points of BVC (ranged 0.2-1.2%), presence of active lesions (≥ 1 for EDA/≥ 3 for RS), relapses, and 6-month confirmed disability progression (CDP), measured by the Expanded Disability Status Scale, after 1 year. Sensitivity, specificity, and positive and negative predictive values for predicting confirmed disability progression at 4 years in original EDA (EDA-3) and RS (RS-3) as well as EDA and RS including BVC (EDA-4 and RS-4) were compared.

RESULTS

Adding BVC to EDA slightly increased sensitivity, but not specificity or predictive values, nor the OR for predicting CDP; only EDA-3 showed a trend for predicting CDP (OR 3.701, p = 0.050). Adding BVC to RS-3 (defined as ≥ 2 criteria) helped to improve sensitivity and negative predictive value, and increased OR for predicting CDP using a cutoff of ≤ - 0.86% (RS-3 OR 23.528, p < 0.001; RS-4 for all cutoffs ranged from 15.06 to 32, p < 0.001). RS-4 showed areas under the curve larger than RS-3 for prediction of disability at 4 years.

CONCLUSION

Addition of BVC to RS improves its prediction of response to interferon-beta.

Chronic white matter lesion activity predicts clinical progression in primary progressive multiple sclerosis

Chronic active and slowly expanding lesions with smouldering inflammation are neuropathological correlates of progressive multiple sclerosis pathology. T₁ hypointense volume and signal intensity on T₁-weighted MRI reflect brain tissue damage that may develop within newly formed acute focal inflammatory lesions or in chronic pre-existing lesions without signs of acute inflammation. Using a recently developed method to identify slowly expanding/evolving lesions in vivo from longitudinal conventional T₂- and T₁-weighted brain MRI scans, we measured the relative amount of chronic lesion activity as measured by change in T₁ volume and intensity within slowly expanding/evolving lesions and non-slowly expanding/evolving lesion areas of baseline pre-existing T₂ lesions, and assessed the effect of ocrelizumab on this outcome in patients with primary progressive multiple sclerosis participating in the phase III, randomized, placebo-controlled, double-blind ORATORIO study (n = 732, NCT01194570). We also assessed the predictive value of T₁-weighted measures of chronic lesion activity for clinical multiple sclerosis progression as reflected by a composite disability measure including the Expanded Disability Status Scale, Timed 25-Foot Walk and 9-Hole Peg Test. We observed in this clinical trial population that most of total brain non-enhancing T₁ hypointense lesion volume accumulation was derived from chronic lesion activity within pre-existing T₂ lesions rather than new T₂ lesion formation. There was a larger decrease in mean normalized T₁ signal intensity and greater relative accumulation of T₁ hypointense volume in slowly expanding/evolving lesions compared with non-slowly expanding/evolving lesions. Chronic white matter lesion activity measured by longitudinal T₁ hypointense lesion volume accumulation in slowly expanding/evolving lesions and in non-slowly expanding/evolving lesion areas of pre-existing lesions predicted subsequent composite disability progression with consistent trends on all components of the composite. In contrast, whole brain volume loss and acute lesion activity measured by longitudinal T₁ hypointense lesion volume accumulation in new focal T₂ lesions did not predict subsequent composite disability progression in this trial at the population level. Ocrelizumab reduced longitudinal measures of chronic lesion activity such as T₁ hypointense lesion volume accumulation and mean normalized T₁ signal intensity decrease both within regions of pre-existing T₂ lesions identified as slowly expanding/evolving and in non-slowly expanding/evolving lesions. Using conventional brain MRI, T₁-weighted intensity-based measures of chronic white matter lesion activity predict clinical progression in primary progressive multiple sclerosis and may qualify as a longitudinal in vivo neuroimaging correlate of smouldering demyelination and axonal loss in chronic active lesions due to CNS-resident inflammation and/or secondary neurodegeneration across the multiple sclerosis disease continuum.

Disease activity impacts disability progression in primary progressive multiple sclerosis

BACKGROUND

Although solid information on the natural history of primary progressive multiple sclerosis (PPMS) is available, evidence regarding impact of disease activity on PPMS progression remains controversial.

OBJECTIVE

To describe the clinical characteristics, presence or absence of MRI activity, and natural history of a PPMS cohort from two referral centers in Argentina and assess whether clinical and/or radiological disease activity correlated with disability worsening.

METHODS

Retrospective study conducted at two MS clinics in Buenos Aires, Argentina, through comparative analysis of patients with and without evidence of disease activity.

RESULTS

Clinical and/or radiologic activity was presented in 56 (31%) of 178 patients. When stratified by age at onset, we found that for every 10 years of increase in age at onset, risk of reaching EDSS scores of 4 and 6 increased by 26% and 31%, respectively (EDSS 4: HR 1.26, CI 95%: 1.06-1.50; EDSS 6: HR 1.31, CI 95%: 1.06-1.62). Patients who presented clinical exacerbations reached EDSS scores of 6, 7 and 8 faster than those without associated exacerbations (p = 0.009, p = 0.016 and p = 0.001, respectively). Likewise, patients who presented gadolinium-enhancing lesions during the course of disease reached EDSS scores of 7 earlier (p = 0.002).

CONCLUSION

Older age at onset and presence of clinical and/or radiological disease activity correlated with accelerated disability progression in this cohort of PPMS patients.

MAGNIMS consensus recommendations on the use of brain and spinal cord atrophy measures in clinical practice

Early evaluation of treatment response and prediction of disease evolution are key issues in the management of people with multiple sclerosis (MS). In the past 20 years, MRI has become the most useful paraclinical tool in both situations and is used clinically to assess the inflammatory component of the disease, particularly the presence and evolution of focal lesions - the pathological hallmark of MS. However, diffuse neurodegenerative processes that are at least partly independent of inflammatory mechanisms can develop early in people with MS and are closely related to disability. The effects of these neurodegenerative processes at a macroscopic level can be quantified by estimation of brain and spinal cord atrophy with MRI. MRI measurements of atrophy in MS have also been proposed as a complementary approach to lesion assessment to facilitate the prediction of clinical outcomes and to assess treatment responses. In this Consensus statement, the Magnetic Resonance Imaging in MS (MAGNIMS) study group critically review the application of brain and spinal cord atrophy in clinical practice in the management of MS, considering the role of atrophy measures in prognosis and treatment monitoring and the barriers to clinical use of these measures. On the basis of this review, the group makes consensus statements and recommendations for future research.

Spinal Cord Atrophy in Multiple Sclerosis: A Systematic Review and Meta-Analysis

BACKGROUND AND PURPOSE

Spinal cord atrophy (SCA) is an important emerging outcome measure in multiple sclerosis (MS); however, there is limited consensus on the magnitude and rate of atrophy. The objective of this study was to synthesize the available data on measures of SCA in MS.

METHODS

Using published guidelines, relevant literature databases were searched between 1977 and 2017 for case-control or cohort studies reporting a quantitative measure of SCA in MS patients. Random-effects models pooled cross-sectional measures and longitudinal rates of SCA in MS and healthy controls (HCs). Student's t-test assessed differences between pooled measures in patient subgroups. Heterogeneity was assessed using DerSimonian and Laird's Q-test and the I ² -index.

RESULTS

A total of 1,465 studies were retrieved including 94 that met inclusion and exclusion criteria. Pooled estimates of mean cervical spinal cord (SC) cross-sectional area (CSA) in all MS patients, relapsing-remitting MS (RRMS), all progressive MS, secondary progressive MS (SPMS), primary-progressive MS (PPMS), and HC were: 73.07 mm² (95% CI [71.52-74.62]), 78.88 mm² (95% CI [76.92-80.85]), 69.72 mm² (95% CI [67.96-71.48]), 68.55 mm² (95% CI [65.43-71.66]), 70.98 mm² (95% CI [68.78-73.19]), and 80.87 mm² (95% C I [78.70-83.04]), respectively. Pooled SC-CSA was greater in HC versus MS (P < .001) and RRMS versus progressive MS (P < .001). SCA showed moderate correlations with global disability in cross-sectional studies (r-value with disability score range [-.75 to -.22]). In longitudinal studies, the pooled annual rate of SCA was 1.78%/year (95%CI [1.28-2.27]).

CONCLUSIONS

The SC is atrophied in MS. The magnitude of SCA is greater in progressive versus relapsing forms and correlates with clinical disability. The pooled estimate of annual rate of SCA is greater than reported rates of brain atrophy in MS. These results demonstrate that SCA is highly relevant as an imaging outcome in MS clinical trials.

Cervical Cord Atrophy and Long-Term Disease Progression in Patients with Primary-Progressive Multiple Sclerosis

BACKGROUND AND PURPOSE

Cervical cord atrophy has been associated with clinical disability in multiple sclerosis and is proposed as an outcome measure of neurodegeneration. The aim of this study was to quantify the development of cervical cord atrophy and to evaluate its association with disability progression in patients with primary-progressive multiple sclerosis.

MATERIALS AND METHODS

Thirty-one patients with primary-progressive multiple sclerosis underwent 1.5T brain and spinal cord MR imaging at baseline and 6-7 years later. The cervical spinal cord from C1 to C5 was segmented to evaluate the normalized overall cross-sectional area and the cross-sectional area of C2-C3, C3-C4, and C4-C5. The annualized rates of normalized cross-sectional area loss were also evaluated. To estimate clinical progression, we determined the Expanded Disability Status Scale score at baseline and at 2 and 14 years after baseline to compute the normalized area under the curve of the Expanded Disability Status Scale and the Expanded Disability Status Scale changes from baseline to the follow-up time points. Associations between the cord cross-sectional area and brain MR imaging and clinical measures were also investigated. Finally, the value of all these measures for predicting long-term disability was evaluated.

RESULTS

Some normalized cross-sectional area measurements showed moderate correlations with the normalized area under the curve of the Expanded Disability Status Scale, ranging from -0.439 to -0.359 (P < .05). Moreover, the annualized rate of the normalized mean cross-sectional area loss and the baseline Expanded Disability Status Scale were independent predictors of long-term disability progression.

CONCLUSIONS

These data indicate that development of cervical cord atrophy is associated with progression of disability and is predictive of this event in patients with primary-progressive MS.

Alemtuzumab CARE-MS II 5-year follow-up: Efficacy and safety findings

OBJECTIVE

To evaluate 5-year efficacy and safety of alemtuzumab in patients with active relapsing-remitting multiple sclerosis and inadequate response to prior therapy.

METHODS

In the 2-year Comparison of Alemtuzumab and Rebif Efficacy in Multiple Sclerosis (CARE-MS) II study (NCT00548405), alemtuzumab-treated patients received 2 courses (baseline and 12 months later). Patients could enter an extension (NCT00930553), with as-needed alemtuzumab retreatment for relapse or MRI activity. Annualized relapse rate (ARR), 6-month confirmed disability worsening (CDW; ≥1-point Expanded Disability Status Scale [EDSS] score increase [≥1.5 if baseline EDSS = 0]), 6-month confirmed disability improvement (CDI; ≥1-point EDSS decrease [baseline score ≥2.0]), no evidence of disease activity (NEDA), brain volume loss (BVL), and adverse events (AEs) were assessed.

RESULTS

Most alemtuzumab-treated patients (92.9%) who completed CARE-MS II entered the extension; 59.8% received no alemtuzumab retreatment. ARR was low in each extension year (years 3-5: 0.22, 0.23, 0.18). Through 5 years, 75.1% of patients were free of 6-month CDW; 42.9% achieved 6-month CDI. In years 3, 4, and 5, proportions with NEDA were 52.9%, 54.2%, and 58.2%, respectively. Median yearly BVL remained low in the extension (years 1-5: -0.48%, -0.22%, -0.10%, -0.19%, -0.07%). AE exposure-adjusted incidence rates in the extension were lower than in the core study. Thyroid disorders peaked at year 3, declining thereafter.

CONCLUSIONS

Alemtuzumab provides durable efficacy through 5 years in patients with an inadequate response to prior therapy in the absence of continuous treatment.

CLASSIFICATION OF EVIDENCE

This study provides Class III evidence that alemtuzumab provides efficacy and slowing of brain atrophy through 5 years.

CXCL10 and CXCL13 chemokines in patients with relapsing remitting and primary progressive multiple sclerosis

OBJECTIVES

Multiple sclerosis (MS) is a chronic inflammatory demyelinating disease of the central nervous system characterized by a variable clinical course. Different pathogenic mechanisms responsible for relapsing remitting (RRMS) and primary progressive multiple sclerosis (PPMS) are modulated by immunological process with important role of chemokine network. CXCL10 and CXCL13 chemokines act as chemoattractants and modulators of proinflammatory reactions promoting process of demyelination. In the present study, we investigated the concentrations of CXCL10 and CXCL13 in serum and cerebrospinal fluid (CSF) of patients with RRMS and PPMS.

MATERIALS AND METHODS

The study groups comprised 25 RRMS patients (39,5±12years), 24 PPMS patients (49,9±10,5years), 31 healthy individuals (36±10,4years) with tension headache without symptoms of inflammatory diseases. A quantitive test kit based on ELISA has been used for chemokines measurement. Correlations analysis between the levels of CXCL10, CXCL13 and patient age, duration of MS, EDSS and IgG index were done.

RESULTS

The mean concentration of CXCL10 in the CSF was statistically significantly higher in RRMS in comparison with the control group. The mean concentration of CXCL13 in the CSF was significantly higher in RRMS and PPMS than in the control group. The results have shown that in the stable phase of MS without relapse, mean concentration of CXCL10 and CXCL13 in CSF did not differ significantly between RRMS and PPMS. In PPMS a positive correlation between IgG index and CSF CXCL10 level or CSF CXCL13 level was observed. In RRMS a positive correlation between IgG index and CSF CXCL13 level was observed.

CONCLUSIONS

These data indicate involvement of CXCL10 and CXCL13 chemokines in immunopathogenetic mechanisms in MS. There was no significant difference between mean CXCL10 or CXCL13 concentrations in the CSF in both RRMS and PPMS patients. No significant correlations were found between patient age and chemokines levels in theCSF in all groups. It suggest that these chemokines play similar role in inflammatory process despite more pronounced neurodegenerative process in PPMS.

Imaging of noninfectious inflammatory disorders of the spinal cord

Myelitis, or inflammation of the spinal cord, produces a characteristic clinical syndrome. Among the many causes of myelitis are the prototypical demyelinating diseases multiple sclerosis and neuromyelitis optica, each of which has distinct clinical, pathologic, and radiographic features. Less distinct are the myelitides associated with systemic autoimmune conditions like sarcoidosis and lupus. Nondemyelinating conditions such as arachnoiditis, dural arteriovenous fistula, and tumor infiltration may also produce inflammation of the spinal cord. The objective of this review is to aid the clinician in the radiographic diagnosis of noninfectious inflammatory diseases of the spinal cord.

A Personalized Approach in Progressive Multiple Sclerosis: The Current Status of Disease Modifying Therapies (DMTs) and Future Perspectives

Using the term of progressive multiple sclerosis (PMS), we considered a combined population of persons with secondary progressive MS (SPMS) and primary progressive MS (PPMS). These forms of MS cannot be challenged with efficacy by the licensed therapy. In the last years, several measures of risk estimation were developed for predicting clinical course in MS, but none is specific for the PMS forms. Personalized medicine is a therapeutic approach, based on identifying what might be the best therapy for an individual patient, taking into account the risk profile. We need to achieve more accurate estimates of useful predictors in PMS, including unconventional and qualitative markers which are not yet currently available or practicable routine diagnostics. The evaluation of an individual patient is based on the profile of disease activity.Within the neurology field, PMS is one of the fastest-moving going into the future.

Brain Metabolite Changes in Patients with Relapsing-Remitting and Secondary Progressive Multiple Sclerosis: A Two-Year Follow-Up Study

Magnetic resonance spectroscopy (MRS) provides the unique ability to monitor several disease-related pathological processes via their characteristic metabolic markers in vivo. In the present study metabolic compositions were assessed every six months over the period of two years in 36 patients with Multiple Sclerosis (MS) including 21 relapsing-remitting (RR), 15 secondary progressive (SP) patients and 12 normal subjects. The concentrations of the main MRS-detectable metabolites N-acetylaspartate and N-acetylaspartylglutamate (tNAA), creatine and phosphocreatine (tCr), choline containing compounds (Cho), myo-Inositol (Ins), glutamine and glutamate (Glx) and their ratios were calculated in the normal appearing white matter (NAWM) and in selected non-enhancing white matter (WM) lesions. Association between metabolic concentrations in the NAWM and disability were investigated. Concentration of tNAA, a marker for neuroaxonal integrity, did not show any difference between the investigated groups. However, the patients with SPMS showed significant reduction of tNAA in the NAWM over the investigation period of two years indicating diffuse neuroaxonal loss during the disease course. Furthermore, we found a significant increase of Ins, Ins/tCr and Ins/tNAA in WM lesions independently from the course of the disease suggesting ongoing astrogliosis in silent-appearing WM lesions. Analyzing correlations between MRS metabolites in the NAWM and patients clinical status we found the positive correlation of Ins/tNAA with disability in patients with RRMS. In SPMS positive correlation of Cho with disability was found.

Brain and cord myelin water imaging: a progressive multiple sclerosis biomarker

OBJECTIVES

Conventional magnetic resonance imaging (MRI) is used to diagnose and monitor inflammatory disease in relapsing remitting (RR) multiple sclerosis (MS). In the less common primary progressive (PP) form of MS, in which focal inflammation is less evident, biomarkers are still needed to enable evaluation of novel therapies in clinical trials. Our objective was to characterize the association - across the brain and cervical spinal cord - between clinical disability measures in PPMS and two potential biomarkers (one for myelin, and one for atrophy, both resulting from the same imaging technique).

METHODS

Multi-component driven equilibrium single pulse observation of T1 and T2 (mcDESPOT) MRI of the brain and cervical spinal cord were obtained for 15 PPMS patients and 11 matched controls. Data were analysed to estimate the signal related to myelin water (VFM), as well as volume measurements. MS disability was assessed using the Multiple Sclerosis Functional Composite score, which includes measures of cognitive processing (Paced Auditory Serial Addition Test), manual dexterity (9-Hole Peg Test) and ambulatory function (Timed 25-Foot Walk); and the Expanded Disability Status Scale.

RESULTS

Brain and spinal cord volumes were different in PPMS compared to controls, particularly ventricular (+ 46%, p = 0.0006) and cervical spinal cord volume (- 16%, p = 0.0001). Brain and spinal cord myelin (VFM) were also reduced in PPMS (brain: - 11%, p = 0.01; spine: - 19%, p = 0.000004). Cognitive processing correlated with brain ventricular volume (p = 0.009). Manual dexterity correlated with brain ventricular volume (p = 0.007), and both brain and spinal cord VFM (p = 0.01 and 0.06, respectively). Ambulation correlated with spinal cord volume (p = 0.04) and spinal cord VFM (p = 0.04).

INTERPRETATION

In this study we demonstrated that mcDESPOT can be used to measure myelin and atrophy in the brain and spinal cord. Results correlate well with clinical disability scores in PPMS representing cognitive, fine motor and ambulatory disability.

Spinal cord MRI in multiple sclerosis--diagnostic, prognostic and clinical value

Multiple sclerosis (MS) is an inflammatory disorder of the CNS that affects both the brain and the spinal cord. MRI studies in MS focus more often on the brain than on the spinal cord, owing to the technical challenges in imaging this smaller, mobile structure. However, spinal cord abnormalities at disease onset have important implications for diagnosis and prognosis. Furthermore, later in the disease course, in progressive MS, myelopathy becomes the primary characteristic of the clinical presentation, and extensive spinal cord pathology--including atrophy, diffuse abnormalities and numerous focal lesions--is common. Recent spinal cord imaging studies have employed increasingly sophisticated techniques to improve detection and quantification of spinal cord lesions, and to elucidate their relationship with physical disability. Quantitative MRI measures of cord size and tissue integrity could be more sensitive to the axonal loss and other pathological processes in the spinal cord than is conventional MRI, putting quantitative MRI in a key role to elucidate the association between disability and spinal cord abnormalities seen in people with MS. In this Review, we summarize the most recent MS spinal cord imaging studies and discuss the new insights they have provided into the mechanisms of neurological impairment. Finally, we suggest directions for further and future research.

Cervical spinal cord volume loss is related to clinical disability progression in multiple sclerosis

OBJECTIVE

To examine the temporal evolution of spinal cord (SC) atrophy in multiple sclerosis (MS), and its association with clinical progression in a large MS cohort.

METHODS

A total of 352 patients from two centres with MS (relapsing remitting MS (RRMS): 256, secondary progressive MS (SPMS): 73, primary progressive MS (PPMS): 23) were included. Clinical and MRI parameters were obtained at baseline, after 12 months and 24 months of follow-up. In addition to conventional brain and SC MRI parameters, the annualised percentage brain volume change and the annualised percentage upper cervical cord cross-sectional area change (aUCCA) were quantified. Main outcome measure was disease progression, defined by expanded disability status scale increase after 24 months.

RESULTS

UCCA was lower in SPMS and PPMS compared with RRMS for all time points. aUCCA over 24 months was highest in patients with SPMS (-2.2% per year) and was significantly higher in patients with disease progression (-2.3% per year) than in stable patients (-1.2% per year; p=0.003), while annualised percentage brain volume change did not differ between subtypes (RRMS: -0.42% per year; SPMS -0.6% per year; PPMS: -0.46% per year) nor between progressive and stable patients (p=0.055). Baseline UCCA and aUCCA over 24 months were found to be relevant contributors of expanded disability status scale at month-24, while baseline UCCA as well as number of SC segments involved by lesions at baseline but not aUCCA were relevant contributors of disease progression.

CONCLUSIONS

SC MRI parameters including baseline UCCA and SC lesions were significant MRI predictors of disease progression. Progressive 24-month upper SC atrophy occurred in all MS subtypes, and was faster in patients exhibiting disease progression at month-24.

Therapeutic strategies for relapsing-remitting multiple sclerosis: a special focus on reduction of grey matter damage as measured by brain atrophy

In the past two decades, several pathological and radiological findings convincingly demonstrated that damage of the cortical and deep grey matter is a key issue in multiple sclerosis with a significant impact on physical and cognitive disability. Moreover, it has become increasingly evident that the effect of available therapies on the inflammatory white matter damage is not a guarantee of a meaningful effect on the neurodegenerative process mainly affecting the grey matter. Despite the efficacy of all approved disease-modifying drugs should be measured considering such a relevant aspect of the disease, data from clinical trials are few, scattered and heterogeneous. The aim of this review is to summarize the evidence so far acquired on the effect of reducing grey matter damage produced by current and emerging disease-modifying therapies for multiple sclerosis.

Brain atrophy in natalizumab-treated patients: A 3-year follow-up

Background:

A pseudoatrophy effect has been held responsible for the lack of net impact of natalizumab on brain volume outcomes in 2-year trials, but no data are available beyond 24 months.

Objective:

We aimed to investigate brain volume dynamics in natalizumab-treated patients in up to 3 years after therapy initiation with clinical correlations.

Methods:

Patients on natalizumab for at least 3 years were clinically assessed 3-monthly. Magnetic resonance imaging scans were performed at baseline and yearly. Brain volume changes were obtained with SIENA. Multivariate models were used to investigate the association between baseline inflammation and changes in brain volume and disability.

Results:

Sixty-two patients with multiple sclerosis were analysed. Mean age and disease duration were 34.7 (SD: 8.3) and 10.4 (SD: 6.6) years. Presence of gadolinium enhancement at baseline was not associated with Expanded Disability Status Scale changes ( p=0.468), but was associated with larger brain volume decreases ( p=0.005) in the first ( p=0.024) and second year ( p=0.019) but not in the third year ( p=0.863). Brain volume changes at 12 and 36 months were marginally associated with disability status at month 12 ( p=0.094) and 36 ( p=0.084), respectively.

Conclusions:

Baseline inflammation affects brain volume measures up to 24 months after natalizumab initiation. A marginal association of brain volume changes with disability is present.

Brain atrophy and lesion load predict long term disability in multiple sclerosis

OBJECTIVE

To determine whether brain atrophy and lesion volumes predict subsequent 10 year clinical evolution in multiple sclerosis (MS).

DESIGN

From eight MAGNIMS (MAGNetic resonance Imaging in MS) centres, we retrospectively included 261 MS patients with MR imaging at baseline and after 1-2 years, and Expanded Disability Status Scale (EDSS) scoring at baseline and after 10 years. Annualised whole brain atrophy, central brain atrophy rates and T2 lesion volumes were calculated. Patients were categorised by baseline diagnosis as primary progressive MS (n=77), clinically isolated syndromes (n=18), relapsing-remitting MS (n=97) and secondary progressive MS (n=69). Relapse onset patients were classified as minimally impaired (EDSS=0-3.5, n=111) or moderately impaired (EDSS=4-6, n=55) according to their baseline disability (and regardless of disease type). Linear regression models tested whether whole brain and central atrophy, lesion volumes at baseline, follow-up and lesion volume change predicted 10 year EDSS and MS Severity Scale scores.

RESULTS

In the whole patient group, whole brain and central atrophy predicted EDSS at 10 years, corrected for imaging protocol, baseline EDSS and disease modifying treatment. The combined model with central atrophy and lesion volume change as MRI predictors predicted 10 year EDSS with R(2)=0.74 in the whole group and R(2)=0.72 in the relapse onset group. In subgroups, central atrophy was predictive in the minimally impaired relapse onset patients (R(2)=0.68), lesion volumes in moderately impaired relapse onset patients (R(2)=0.21) and whole brain atrophy in primary progressive MS (R(2)=0.34).

CONCLUSIONS

This large multicentre study points to the complementary predictive value of atrophy and lesion volumes for predicting long term disability in MS.

Primary progressive multiple sclerosis: part of the MS disease spectrum or separate disease entity?

Multiple sclerosis (MS), the most frequent demyelinating disease, is characterized by a variable disease course. The majority of patients starts with relapsing remitting (RR) disease; approximately 50-60% of these patients progress to secondary progressive (SP) disease. Only about 15% of the patients develop a progressive disease course from onset, termed primary progressive multiple sclerosis (PPMS); the underlying pathogenic mechanisms responsible for onset of the disease with either PPMS or relapsing remitting multiple sclerosis (RRMS) are unknown. Patients with PPMS do not show a female predominance and usually have a later onset of disease compared to patients with RRMS. Monozygous twins can be concordant or discordant for disease courses indicating that the disease course is not only genetically determined. Primary progressive multiple sclerosis and secondary progressive multiple sclerosis (SPMS) share many similarities in imaging and pathological findings. Differences observed among the different disease courses are more of a quantitative than qualitative nature suggesting that the different phenotypes are part of a disease spectrum modulated by individual genetic predisposition and environmental influences. In this review, we summarize the knowledge regarding the clinical, epidemiological, imaging, and pathological characteristics of PPMS and compare those characteristics with RRMS and SPMS.

T2 lesion location really matters: a 10 year follow-up study in primary progressive multiple sclerosis

OBJECTIVES

Prediction of long term clinical outcome in patients with primary progressive multiple sclerosis (PPMS) using imaging has important clinical implications, but remains challenging. We aimed to determine whether spatial location of T2 and T1 brain lesions predicts clinical progression during a 10-year follow-up in PPMS.

METHODS

Lesion probability maps of the T2 and T1 brain lesions were generated using the baseline scans of 80 patients with PPMS who were clinically assessed at baseline and then after 1, 2, 5 and 10 years. For each patient, the time (in years) taken before bilateral support was required to walk (time to event (TTE)) was used as a measure of progression rate. The probability of each voxel being 'lesional' was correlated with TTE, adjusting for age, gender, disease duration, centre and spinal cord cross sectional area, using a multiple linear regression model. To identify the best, independent predictor of progression, a Cox regression model was used.

RESULTS

A significant correlation between a shorter TTE and a higher probability of a voxel being lesional on T2 scans was found in the bilateral corticospinal tract and superior longitudinal fasciculus, and in the right inferior fronto-occipital fasciculus (p<0.05). The best predictor of progression rate was the T2 lesion load measured along the right inferior fronto-occipital fasciculus (p=0.016, hazard ratio 1.00652, 95% CI 1.00121 to 1.01186).

CONCLUSION

Our results suggest that the location of T2 brain lesions in the motor and associative tracts is an important contributor to the progression of disability in PPMS, and is independent of spinal cord involvement.

Primary progressive multiple sclerosis diagnostic criteria: a reappraisal

The diagnostic criteria used in primary progressive (PP) and relapsing-remitting (RR) multiple sclerosis (MS) show substantial differences. This introduces complexity in the diagnosis of MS which could be resolved if these criteria could be unified in terms of the requirements for dissemination in space (DIS). The aim of this study was to assess whether a single algorithm may be used to demonstrate DIS in all forms of MS. Five sets of RRMS criteria for DIS were applied to a cohort of 145 patients with established PPMS (mean disease duration: 11 years - PPMS-1): C1: Barkhof-Tintoré (as in 2005 McDonald's criteria); C2: Swanton et al. (as in JNNP 2006); C3: presence of oligoclonal bands plus two lesions (as in McDonald's criteria); C4 and C5: a two-step approach was also followed (patients not fulfilling C1 or C2 were then assessed for C3). Two sets of PPMS criteria for DIS were applied: C6: Thompson et al. (as in 2001 McDonald's criteria); C7: 2005 McDonald criteria. A second sample of 55 patients with less than 5 years of disease duration (PPMS-2) was also analysed using an identical approach. For PPMS-1/PPMS-2, fulfilment was: C1:73.8%/66.7%; C2:72.1%/59.3%; C3:89%/79.2%; C4:96%/92.3%; C5:96%/85.7%; C6:85.8%/78.7%; C7:91%/80.4%. Levels of fulfilment suggest that the use of a single set of criteria for DIS in RRMS and PPMS might be feasible, and reinforce the added value of cerebrospinal fluid (CSF) findings to increase fulfilment in PPMS. Unification of the DIS criteria for both RRMS and PPMS could be considered in further revisions of the MS diagnostic criteria.

Reactive astrocytes form scar-like perivascular barriers to leukocytes during adaptive immune inflammation of the CNS

Factors that regulate leukocyte entry and spread through CNS parenchyma during different types of CNS insults are incompletely understood. Reactive astrocytes have been implicated in restricting the spread of leukocytes from damaged into healthy parenchyma during the acute and local innate inflammatory events that follow CNS trauma, but the roles of reactive astrocytes during the chronic and widespread CNS inflammation associated with adaptive or acquired immune responses are uncertain. Here, we investigated the effects of transgenically targeted ablation of proliferating, scar-forming reactive astrocytes on the acquired immune inflammation associated with experimental autoimmune encephalitis (EAE). In wild-type mice with EAE, we found that reactive astrocytes densely surrounded perivascular clusters of leukocytes in a manner reminiscent of astrocyte scar formation after CNS trauma. Transgenically targeted ablation of proliferating astrocytes disrupted formation of these perivascular scars and was associated with a pronounced and significant increase in leukocyte entry into CNS parenchyma, including immunohistochemically identified macrophages, T lymphocytes and neutrophils. This exacerbated inflammation was associated with a substantially more severe and rapidly fulminant clinical course. These findings provide experimental evidence that reactive astrocytes form scar-like perivascular barriers that restrict the influx of leukocytes into CNS parenchyma and protect CNS function during peripherally initiated, acquired immune inflammatory responses in the CNS. The findings suggest that loss or disruption of astrocyte functions may underlie or exacerbate the inflammation and pathologies associated with autoimmune diseases of the CNS, including multiple sclerosis.

A single-center, randomized, double-blind, placebo-controlled study of interferon beta-1b on primary progressive and transitional multiple sclerosis

Inflammation and neurodegeneration may have differential impacts on disease evolution in the different forms of multiple sclerosis. However, a beneficial effect of immunomodulatory drugs should not be ruled out in primary progressive multiple sclerosis. Our aim is to investigate the safety and efficacy of interferon beta-1b in primary progressive multiple sclerosis. We conducted a double-blind, stratified, randomized, parallel group, phase II pilot study where patients with primary progressive multiple sclerosis or ‘transitional’ forms of multiple sclerosis received interferon beta-1b at doses of 8 MIU or placebo for 24 months. The main objective of the study was to investigate the safety and tolerability of interferon beta-1b. The primary efficacy variable was the time to neurological deterioration (Expanded Disability Status Scale) confirmed at 3 months. Seventy-three patients were included and three dropped out the study. More patients in the treatment arm had at least one related adverse event (94.4% versus 45.9%; p < 0.001); no other significant differences in safety endpoints were observed. Time to neurological deterioration was not different between trial arms (log-rank test, p = 0.3135). Statistically significant differences favoring treatment were observed for the Multiple Sclerosis Functional Composite score at several timepoints, T1 and T2 lesion volume changes at 12 and 24 months, mean number of active lesions and proportion of patients with active lesions at 24 months. We conclude that interferon beta-1b is safe and well tolerated in patients with primary progressive multiple sclerosis and transitional multiple sclerosis. Positive effects of interferon beta on secondary clinical and magnetic resonance imaging outcomes were observed, but a beneficial effect on Expanded Disability Status Scale progression was not demonstrated.

Cerebrospinal fluid biomarkers in multiple sclerosis

In patients with multiple sclerosis (MS) intensive efforts are directed at identifying biomarkers in bodily fluids related to underlying disease mechanisms, disease activity and progression, and therapeutic response. Besides MR imaging parameters cerebrospinal fluid (CSF) biomarkers provide important and specific information since changes in the CSF composition may reflect disease mechanisms inherent to MS. The different cellular and protein-analytical methods of the CSF and the recommended standard of the diagnostic CSF profile in MS are described. A brief update on possible CSF biomarkers that might reflect key pathological processes of MS such as inflammation, demyelination, neuroaxonal loss, gliosis and regeneration is provided.

New treatment measurements for treatment effects on relapses and progression

Multiple sclerosis (MS) is considered to be a two stage disease: a first stage in which inflammatory phenomena are crucial and a later one in which degenerative processes become the hallmark. The role of magnetic resonance imaging (MRI) is nowadays of great help both to establish the diagnosis and to rule out other conditions. At the clinically isolated syndrome (CIS) stage, MRI is an important tool both to predict the appearance of a second attack or the development of disability at long term. In the relapsing-remitting (RR) phase of the disease conventional MRI is probably less helpful to predict future relapses and disability. Cross sectional and longitudinal studies have shown very weak correlations between lesion burden on brain T2 and disability in the progressive forms of MS. Regarding T2 burden of disease, a plateau effect for EDSS values greater than 4.5 has been observed. Measures related to brain or spinal cord atrophy together with MR Spectroscopy, Magnetization Transfer Imaging and Diffusion Tensor Imaging may be useful in the future to better monitor disease progression in the late degenerative phase of the condition. MRI has also been of great help in monitoring the effect of immunomodulatory drugs in CIS or RRMS clinical trials. Its role to predict treatment response is still controversial on an individual basis.

Predicting progression in primary progressive multiple sclerosis: a 10-year multicenter study

Rates of progression vary widely in primary progressive multiple sclerosis. This multicenter study aimed to identify predictors of progression over 10 years. A total of 101 patients who had been imaged at baseline and 2 years were scored on the expanded disability status scale after 10 years. Ordinal logistic regression identified the following independent variables that predicted progression: male sex, shorter disease duration, and slower timed walk test at baseline (best overall predictor), and deterioration in expanded disability status scale score and reduction in brain volume over 2 years. These predictors of long-term disability provide some insight into disease progression.

Magnetic resonance imaging measures of brain and spinal cord atrophy correlate with clinical impairment in secondary progressive multiple sclerosis

BACKGROUND

Neuroaxonal loss is a pathological substrate of disability in progressive multiple sclerosis (MS) and can be estimated in vivo by measuring tissue atrophy on magnetic resonance imaging (MRI). While there is some evidence that brain atrophy correlates better with disability than T2 lesion load in secondary progressive MS, the clinical relevance of atrophy within specific regions of the central nervous system requires further evaluation.

METHODS

Clinical and MRI examinations were performed in 117 subjects with secondary progressive MS. MRI analysis included measures of normalized brain volume (NBV), normalized grey matter (NGMV) and white matter volume (NWMV), central cerebral volume (CCV), spinal cord cross-sectional area (SCCA), and brain T2 and T1 lesion volume. Clinical assessments included the expanded disability status scale (EDSS) and MS functional composite (MSFC).

RESULTS

All MRI measures correlated significantly with the MSFC score, with the strongest correlation being for the NBV (r = 0.47; P < 0.001). NBV and SCCA were the only significant independent predictors of the MSFC score in a stepwise regression model containing all the MRI measures, and SCCA was the only MRI measure to show a significant association with the EDSS. While NGMV had stronger correlations with the clinical variables than NWMV, NBV was more correlated with clinical impairment than either measure.

CONCLUSIONS

This data suggests that measures of atrophy, particularly of the whole brain and spinal cord, are relevant and useful disease markers in secondary progressive MS.

Primary-progressive multiple sclerosis

About 10-15% of patients with multiple sclerosis (MS) present with gradually increasing neurological disability, a disorder known as primary-progressive multiple sclerosis (PPMS). Compared with relapse-onset multiple sclerosis, people with PPMS are older at onset and a higher proportion are men. Inflammatory white-matter lesions are less evident but diffuse axonal loss and microglial activation are seen in healthy-looking white matter, in addition to cortical demyelination, and quantitative MRI shows atrophy and intrinsic abnormalities in the grey matter and the white matter. Spinal cord atrophy corresponds to the usual clinical presentation of progressive spastic paraplegia. Although neuroaxonal degeneration seems to underlie PPMS, the pathogenesis and the extent to which immune-mediated mechanisms operate is unclear. MRI of the brain and spinal cord, and examination of the CSF, are important investigations for diagnosis; conventional immunomodulatory therapies, such as interferon beta and glatiramer acetate, are ineffective. Future research should focus on the clarification of the mechanisms of axonal loss, improvements to the design of clinical trials, and the development of effective neuroprotective treatments.

Measuring brain atrophy in multiple sclerosis

The last decade has seen the development of methods that use conventional magnetic resonance imaging (MRI) to provide sensitive and reproducible assessments of brain volumes. This has increased the interest in brain atrophy measurement as a reliable indicator of disease progression in many neurological disorders, including multiple sclerosis (MS). After a brief introduction in which we discuss the most commonly used methods for assessing brain atrophy, we will review the most relevant MS studies that have used MRI-based quantitative measures of brain atrophy, the clinical importance of these results, and the potential for future application of these measures to understand MS pathology and progression. Despite the number of issues that still need to be solved, the measurement of brain atrophy by MRI is sufficiently precise and accurate. It represents one of most promising in vivo measures of neuroaxonal degeneration in MS, and it should be used extensively in the future to assess and monitor pathological evolution and treatment efficacy in this disease.

Prognostic Factors in Multiple Sclerosis

Prognostic factors to determine the patient's likelihood of developing MS are important for several reasons. Prognostic factors are important to the patient who wants to be informed about his/her prospects, to the clinician who needs to individuate the patients who deserve immune treatments, and to the researcher who needs to improve the design and the analysis of the therapeutic trials. In addition, with the development of new immune therapies, whose early use is strongly encouraged, it is crucial to dispose of reliable clinical predictors to identify the patients who are candidates for early or aggressive therapies. Several studies have indicated that a poor prognosis is related to male gender; a late age at onset; motor, cerebellar, and sphincter involvement at onset; a progressive course at onset; a short inter-attack interval; a high number of early attacks; and a relevant early residual disability. Paraclinical support for MS prognosis is given by imaging techniques, cerebrospinal fluid analysis, and evoked potential examinations. The most sensitive paraclinical test to predict conversion from suspected demyelinating disease to definite MS is MRI.