Automatic Assessment of the 2-Minute Walk Distance for Remote Monitoring of People with Multiple Sclerosis.

The aim of this study was to investigate the feasibility of automatically assessing the 2-Minute Walk Distance (2MWD) for monitoring people with multiple sclerosis (pwMS). For 154 pwMS, MS-related clinical outcomes as well as the 2MWDs as evaluated by clinicians and derived from accelerometer data were collected from a total of 323 periodic clinical visits. Accelerometer data from a wearable device during 100 home-based 2MWD assessments were also acquired. The error in estimating the 2MWD was validated for walk tests performed at hospital, and then the correlation (r) between clinical outcomes and home-based 2MWD assessments was evaluated. Robust performance in estimating the 2MWD from the wearable device was obtained, yielding an error of less than 10% in about two-thirds of clinical visits. Correlation analysis showed that there is a strong association between the actual and the estimated 2MWD obtained either at hospital (r = 0.71) or at home (r = 0.58). Furthermore, the estimated 2MWD exhibits moderate-to-strong correlation with various MS-related clinical outcomes, including disability and fatigue severity scores. Automatic assessment of the 2MWD in pwMS is feasible with the usage of a consumer-friendly wearable device in clinical and non-clinical settings. Wearable devices can also enhance the assessment of MS-related clinical outcomes.

Connecting real-world digital mobility assessment to clinical outcomes for regulatory and clinical endorsement-the Mobilise-D study protocol.

BACKGROUND: The development of optimal strategies to treat impaired mobility related to ageing and chronic disease requires better ways to detect and measure it. Digital health technology, including body worn sensors, has the potential to directly and accurately capture real-world mobility. Mobilise-D consists of 34 partners from 13 countries who are working together to jointly develop and implement a digital mobility assessment solution to demonstrate that real-world digital mobility outcomes have the potential to provide a better, safer, and quicker way to assess, monitor, and predict the efficacy of new interventions on impaired mobility. The overarching objective of the study is to establish the clinical validity of digital outcomes in patient populations impacted by mobility challenges, and to support engagement with regulatory and health technology agencies towards acceptance of digital mobility assessment in regulatory and health technology assessment decisions. METHODS/DESIGN: The Mobilise-D clinical validation study is a longitudinal observational cohort study that will recruit 2400 participants from four clinical cohorts. The populations of the Innovative Medicine Initiative-Joint Undertaking represent neurodegenerative conditions (Parkinson's Disease), respiratory disease (Chronic Obstructive Pulmonary Disease), neuro-inflammatory disorder (Multiple Sclerosis), fall-related injuries, osteoporosis, sarcopenia, and frailty (Proximal Femoral Fracture). In total, 17 clinical sites in ten countries will recruit participants who will be evaluated every six months over a period of two years. A wide range of core and cohort specific outcome measures will be collected, spanning patient-reported, observer-reported, and clinician-reported outcomes as well as performance-based outcomes (physical measures and cognitive/mental measures). Daily-living mobility and physical capacity will be assessed directly using a wearable device. These four clinical cohorts were chosen to obtain generalizable clinical findings, including diverse clinical, cultural, geographical, and age representation. The disease cohorts include a broad and heterogeneous range of subject characteristics with varying chronic care needs, and represent different trajectories of mobility disability. DISCUSSION: The results of Mobilise-D will provide longitudinal data on the use of digital mobility outcomes to identify, stratify, and monitor disability. This will support the development of widespread, cost-effective access to optimal clinical mobility management through personalised healthcare. Further, Mobilise-D will provide evidence-based, direct measures which can be endorsed by regulatory agencies and health technology assessment bodies to quantify the impact of disease-modifying interventions on mobility. TRIAL REGISTRATION: ISRCTN12051706.

The 4-Hole-Board Test for Assessment of Long-Term Spatial Memory in Mice.

The hole-board test has been used in rodents since the early 60s to measure exploratory behavior, locomotor activity and cognitive function. The test is based on rodents' natural curiosity and attraction for novelty. Basically, the hole-board consists of a small square arena with an extractable platform as floor, which has a set of equally spaced circular holes on its surface. In this article, we describe the protocol of a 4-hole-board test allowing the assessment of long-term spatial memory in mice without the employment of water or food restriction, painful stimuli (as electrical shocks) or any aversive condition (as forced swimming or exposure to intense light). Four holes are present on the floor of the square arena (one for each of its four quadrants). Mice released in the arena spontaneously approach the holes and explore them by briefly inserting the snout inside, a behavior defined as nose-poking (or head-dipping). If, after 24 hr, rodents are re-exposed to the hole-board, the novelty of the holes decreases. Animals with an intact long-term memory will show a reduction of the frequency of nose-poking into the holes. The total number of nose-pokes on day 1 is an index of exploration, while the percentage of decrease in nose-poking on day 2 represents an index of long-term spatial memory. Number of quadrant crossings is scored as a control measure for locomotor activity, which with the present protocol should remain stable across the days of testing. Indeed, the 4-hole-board test represents a stress-free and animal-friendly option to evaluate long-term spatial memory. In the present paper, we provide detailed description of the hole-board apparatus and step-by-step protocol for assessment of spatial memory in mice. © 2021 Wiley Periodicals LLC. Basic Protocol 1: Validation of the 4-hole-board Basic Protocol 2: Evaluation of long-term spatial memory through the 4-hole-board test.

Real-time assessment of COVID-19 prevalence among multiple sclerosis patients: a multicenter European study.

We assessed the prevalence and impact of COVID-19 among multiple sclerosis (MS) patients across Europe by leveraging participant data collected as part of the ongoing EU IMI2 RADAR-CNS major programme aimed at finding new ways of monitoring neurological disorders using wearable devices and smartphone technology. In the present study, 399 patients of RADAR-MS have been included (mean age 43.9 years, 60.7% females) with 87/399 patients (21.8%) reporting major symptoms suggestive of COVID-19. A trend for an increased risk of COVID-19 symptoms under alemtuzumab and cladribine treatments in comparison to injectables was observed. Remote monitoring technologies may support health authorities in monitoring and containing the ongoing pandemic.

In vivo structural and functional assessment of optic nerve damage in neuromyelitis optica spectrum disorders and multiple sclerosis.

Early detection of neuromyelitis optica spectrum disorders (NMOSD), especially after optic neuritis, a presenting manifestation commonly observed also in multiple sclerosis (MS), is crucial for timely treatment and prognosis. Integrated visual pathway assessment with optical coherence tomography (OCT) and visual evoked potentials (VEP) may help in this task, showing in vivo different pathophysiological backgrounds. We evaluated combined VEP and OCT in a cross-sectional, single-centre study assessing 50 consecutive NMOSD patients, 57 MS patients and 52 healthy controls. After optic neuritis, VEP were more frequently absent in NMOSD compared to MS; most NMOSD eyes with recordable VEP showed prolonged latency, but extreme latency delays were less common than in MS. OCT showed predominantly axonal involvement in NMOSD, with 88% eyes (95% CI: 69-97%) displaying retinal nerve fibre layer thickness <60 µm even after first optic neuritis episode. Accuracy of OCT was further enhanced by combination with VEP into a new Z-score derived OCT-VEP index, measuring prevalence of axonal damage or demyelination. Our results suggest that integrated optic nerve assessment may elucidate differences in optic neuritis pathophysiology; conduction slowing with relatively preserved nerve fibre layer suggests MS, while severe neuroaxonal loss after optic neuritis, often hindering VEP response, characterizes NMOSD.

The Multiple Sclerosis Care Unit.

Treatment of multiple sclerosis (MS) has become increasingly multifaceted and comprises not only a variety of disease-modifying drugs with different mechanism of action but also a wide range of symptomatic therapies. Today, it is not possible for the family physician or even many general neurologists to master the current treatment algorithm, and this calls for the establishment of multidisciplinary MS Care Units. The core of the MS Care Unit would, in addition to MS neurologists and nurses, typically comprise neuropsychologists, clinical psychologists, physiotherapists, occupational therapists and secretaries, and will work together with a group of different specialists on formalized diagnostic workup procedures, protocols for initiation and follow-up of disease-modifying therapies. It is obvious that the terms of performance of different MS Care Units will vary across regions and need to be balanced with clinical practice according to local conditions. Although the main objective for establishment of MS Care Units will be to offer the single MS patient seamless and correct management of the disease to increase patient satisfaction and quality of life, it may even be cost-effective for the society by maintaining the working ability and reducing the costs of home help and custodial care by keeping people with MS resourceful.

Smart watch, smarter EDSS: Improving disability assessment in multiple sclerosis clinical practice.

BACKGROUND: Patients' walking ability is critical for assessing the EDSS, the disability scale commonly used in MS clinical practice. Such assessment is usually based on patients' estimates or on the measures the neurologists observe during periodic visits. OBJECTIVES AND METHODS: We evaluated the agreement between patients' and neurologists' estimates of maximum walking ability and patients' mean maximum walking ability measured in their daily life through a GPS smartwatch, and assessed limitations of the current methods. RESULTS: Seventy-three patients with a median walking ability of 500m (IQR 400-800) were enrolled in the study. The agreement between patients' estimates and GPS measurements was modest (ICC 0.29, 95% CIs 0.06-0.49) and was influenced by course of the disease, patients' mood and inaccuracy at estimating long distances. A better reliability was found between neurologists' and GPS measures (ICC 0.68, 95% CIs 0.53-0.78), but the variability increased for longer distances and was influenced by patients' depressive symptoms, fatigue and course of the disease. CONCLUSIONS: This study showed a poor agreement between patients' and neurologists' estimates of maximum walking ability and patients' mean maximum walking ability measured in their daily life through a GPS smartwatch, with many factors affecting patient's and neurologists' estimates of the EDSS. The use of remote measurement technologies may provide a better understanding of the impact of MS in a patient's life.

Sativex in resistant multiple sclerosis spasticity: Discontinuation study in a large population of Italian patients (SA.FE. study).

BACKGROUND: The approval of Sativex for the management of multiple sclerosis (MS) spasticity opened a new opportunity to many patients. In Italy, the healthcare payer can be fully reimbursed by the involved pharma company with the cost of treatment for patients not responding after a 4 week (28 days) trial period (Payment by Results, PbR), and 50% reimbursed with the cost of 6 weeks (42 days) treatment for other patients discontinuing (Cost Sharing, CS). The aim of our study was to describe the Sativex discontinuation profile from a large population of spasticity treated Italian MS patients. METHODS: We collected data of patients from 30 MS centres across the country starting Sativex between January 2014 and February 2015. Data were collected from the mandatory Italian Medicines Agency (AIFA) web-registry. Predictors of treatment discontinuation were assessed using a multivariate Cox proportional regression analysis. RESULTS: During the observation period 631 out of 1597 (39.5%) patients discontinued Sativex. The Kaplan-Meier estimates curve showed that 333 patients (20.8%) discontinued treatment at 4 weeks while 422 patients (26.4%) discontinued at 6 weeks. We found after adjusted modeling that a higher NRS score at T1 (adjHR 2.23, 95% 2.07-2.41, p<0.001) and a lower baseline NRS score (adjHR 0.51 95% CI 0.46-0.56, p<0.001) were predictive of treatment discontinuation. CONCLUSION: These data show that the first 6 weeks are useful in identifying those patients in which Sativex could be effective, thus avoiding the cost of longer term evaluation.

Combining Cerebrospinal Fluid Biomarkers and Neuropsychological Assessment: A Simple and Cost-Effective Algorithm to Predict the Progression from Mild Cognitive Impairment to Alzheimer's Disease Dementia.

BACKGROUND: Correctly diagnosing Alzheimer's disease (AD) in prodromal phases would allow the adoption of experimental therapeutic strategies that could selectively interrupt the pathogenetic process before neuronal damage becomes irreversible. Therefore, great efforts have been aimed at finding early reliable disease markers. OBJECTIVE: The aim of this study was to identify a simple, cost effective, and reliable diagnostic algorithm to predict conversion from mild cognitive impairment (MCI) to AD. METHODS: 96 consecutive MCI patients admitted to the Neurology department of San Raffaele Hospital in Milan between January 2009 and January 2015 were included. All patients underwent neuropsychological assessment and lumbar puncture with CSF analysis of amyloid-ß 42 (Aß42), total tau (t-tau), and phosphorylated tau (p-tau) levels. Each patient underwent clinical and neuropsychological follow-up, in order to identify a possible progression from MCI to AD. The mean follow up time was 36.73 months. RESULTS: 37 out of 96 MCI converted to AD during follow up. CSF analysis and neuropsychological assessment reliably detected MCI patients who developed AD. In a subsample of 43 subjects, a Composite Cognitive Score (CCS) was calculated including episodic memory, executive function, and verbal fluency tests. Combining together CSF biomarkers and CCS increased the accuracy of the single predictors, correctly classifying 86% of patients with a specificity of 96% and a Positive Predictive Value of 93%. DISCUSSION: Even if preliminary, our data seem to suggest that CSF analysis and neuropsychological assessment could detect MCI patients who will convert to AD with high confidence. Their relative low cost and availability could make them worldwide essential tools in future clinical trials.

Assessment of cardiac safety during fingolimod treatment initiation in a real-world relapsing multiple sclerosis population: a phase 3b, open-label study.

The aim of this study was to evaluate short-term safety and tolerability of fingolimod in a real-world population with relapsing multiple sclerosis, focusing on cardiac safety during treatment initiation. Patients received fingolimod 0.5 mg once daily for four months. Patients excluded from the pivotal studies with certain pre-existing cardiac conditions or baseline cardiac findings (PCCs), and those receiving beta blockers (BBs) and/or calcium channel blockers (CCBs), were eligible. Heart rate (HR) and electrical conduction events were monitored using ambulatory electrocardiography for at least 6 h after the first dose. Of 2,417 enrolled patients, 2,282 (94.4 %) completed the study. Fingolimod initiation was associated with a transient, mostly asymptomatic decrease in HR. Bradycardia adverse events occurred in 0.6 % of patients and were more frequent in individuals receiving BBs/CCBs (3.3 %) than in other patient subgroups (0.5-1.4 %); most events were asymptomatic, and all patients recovered without pharmacological intervention. In the 6 h post-dose, the incidences of Mobitz type I second-degree atrioventricular block (AVB) and 2:1 AVB were higher in patients with PCCs (4.1 and 2.0 %, respectively) than in those without (0.9 and 0.3 %, respectively); at pre-dose screening, patients with PCCs had the same incidence of Mobitz type I second-degree AVB (4.1 %) and a slightly lower incidence of 2:1 AVB (0.7 %) than 6 h post-dose. All recorded conduction abnormalities were asymptomatic. This study adds to the evidence showing that cardiac effects during fingolimod initiation remain consistent with those known from previous, controlled studies, even if patients with PCCs are included.

Assessment of system dysfunction in the brain through MRI-based connectomics.

Network-based analysis of structural and functional connections has provided a new technique to study the brains of healthy people and patients with neurological and psychiatric disorders. Graph theory provides a powerful method to quantitatively describe the topological organisation of brain connectivity. With such a framework, the brain can be depicted as a set of nodes connected by edges. Distinct modifications of network topological organisation in the brain have been identified during development and normal ageing, whereas disrupted functional and structural connectivities have been associated with several neurological and psychiatric disorders, including dementia, amyotrophic lateral sclerosis, multiple sclerosis, and schizophrenia. These assessments have improved understanding of the clinical manifestations noted in these patients, including disability and cognitive impairment. Future network-based research might enable indentification of different stages of disorders, subtypes for cognitive impairment, and connectivity profiles associated with different clinical outcomes.

Refractory migraine: the role of the physician in assessment and treatment of a problematic disease.

Patients affected by chronic forms of headache are often very difficult to treat. Refractory patients are so defined when adequate trials of specific drugs (for acute or prophylactic treatment) failed both to reduce the burden of disease and to improve headache-related quality of life. An escalating approach is suggested to test different kinds of therapies. All comorbid factors should be addressed. More invasive modalities (such as neurostimulation) or promising approaches such as repetitive transcranial magnetic stimulation (rTMS) could be a future major step as third line therapies.

Quantitative muscle strength assessment in duchenne muscular dystrophy: longitudinal study and correlation with functional measures.

BACKGROUND: The aim of this study was to perform a longitudinal assessment using Quantitative Muscle Testing (QMT) in a cohort of ambulant boys affected by Duchenne muscular dystrophy (DMD) and to correlate the results of QMT with functional measures. This study is to date the most thorough long-term evaluation of QMT in a cohort of DMD patients correlated with other measures, such as the North Star Ambulatory Assessment (NSAA) or three 6-min walk test (6MWT). METHODS: This is a single centre, prospective, non-randomised, study assessing QMT using the Kin Com(®) 125 machine in a study cohort of 28 ambulant DMD boys, aged 5 to 12 years. This cohort was assessed longitudinally over a 12 months period of time with 3 monthly assessments for QMT and with assessment of functional abilities, using the NSAA and the 6MWT at baseline and at 12 months only. QMT was also used in a control group of 13 healthy age-matched boys examined at baseline and at 12 months. RESULTS: There was an increase in QMT over 12 months in boys below the age of 7.5 years while in boys above the age of 7.5 years, QMT showed a significant decrease. All the average one-year changes were significantly different than those experienced by healthy controls. We also found a good correlation between quantitative tests and the other measures that was more obvious in the stronger children. CONCLUSION: Our longitudinal data using QMT in a cohort of DMD patients suggest that this could be used as an additional tool to monitor changes, providing additional information on segmental strength.

Reduction in healthcare and societal resource utilization associated with cladribine tablets in patients with relapsing-remitting multiple sclerosis: analysis of economic data from the CLARITY Study.

BACKGROUND: Multiple sclerosis (MS) is a common, chronic, neurodegenerative condition associated with substantial healthcare and societal economic burden. Disease-modifying MS treatments have the potential to reduce health resource utilization (HRU), thereby reducing the attendant socioeconomic burden. OBJECTIVE: This study aimed to compare health and societal resource use and productivity in patients with relapsing-remitting MS (RRMS) receiving cladribine tablets versus placebo over 96 weeks in the CLARITY study. METHODS: The CLARITY study was a 96-week, randomized, double-blind, placebo-controlled study in patients with RRMS. HRU data, societal resource use and productivity data were collected at baseline and during scheduled patient visits, at 6-month intervals. The recall period for the HRU questionnaire was 3 months. The study was carried out at 155 sites across 32 countries worldwide. The intent-to-treat population comprised 1326 patients with RRMS randomized to cladribine 3.5 mg/kg (n = 433) or 5.25 mg/kg (n = 456) tablets or placebo (n = 437). Patient subgroups with high baseline disease activity were identified based on criteria of ≥2 relapses in the previous year (n = 392); ≥1 T1 gadolinium-enhancing (Gd+) lesion (n = 413); and ≥2 relapses in the previous year plus ≥1 T1 Gd+ lesion (n = 138). Cladribine tablets were administered in two (3.5 mg/kg group) or four (5.25 mg/kg group) short courses given at 4-week intervals at the start of a 48-week treatment period, followed by another two courses at the start of a subsequent 48-week re-treatment period. Interferon-ß rescue therapy was permitted from week 24. Intravenous corticosteroids were available for the treatment of neurological relapses. HRU outcomes included mean number of hospital days and emergency room (ER), clinic and home visits during each study period. Societal resource use and productivity outcomes included mean number of hours and days of paid assistance, mean patient and carer work days missed, and self-reported productivity. RESULTS: The mean number of hospital days per patient over 96 weeks was lower in the cladribine tablets groups (3.5 mg/kg group: -3.19 days; 5.25 mg/kg group: -1.54 days [both p < 0.01]) versus placebo. Likewise the mean number of ER visits was lower in both cladribine tablet groups compared with placebo (3.5 mg/kg group: -0.09 visits; 5.25 mg/kg group: -0.11 visits [both p < 0.01]), and the mean number of clinic visits was also lower in both cladribine tablet groups (3.5 mg/kg group: -0.68 visits; 5.25 mg/kg group: -0.66 visits [both p = 0.01]). Furthermore, treatment with cladribine tablets was associated with reduced mean numbers of missed work days for patients (3.5 mg/kg group: -2.42 days [p < 0.01]; 5.25 mg/kg group: -0.60 days [p = 0.50]). Corticosteroid use was lower amongst patients in the cladribine tablet groups than in the placebo group. The reduction in hospital days following treatment with cladribine tablets was also observed in patients with high disease activity at study baseline. CONCLUSION: This study provides evidence that the efficacy of cladribine tablets observed during the CLARITY study was associated with a reduced consumption of healthcare resources and a decreased need for medical and societal support. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT00213135; EudraCT number: 2004-005148-28.

Assessment of MRI abnormalities of the brainstem from patients with migraine and multiple sclerosis.

BACKGROUND: In patients with migraine, functional changes have been described in the red nucleus (RN), substantia nigra (SN) and periaqueductal gray matter (PAG). PURPOSE: To evaluate whether and at which frequency these structures are involved by MRI-detectable structural abnormalities in migraineurs and to investigate the pathogenic role of these abnormalities by assessing their frequency and extent in patients with multiple sclerosis (MS) and migraine. METHODS: On brain dual-echo scans obtained from 58 migraineurs (40 without and 18 with aura), 37 MS patients with migraine without aura and 42 MS patients without migraine, the presence of hyperintense lesions involving the brainstem structures was recorded. A test of heterogeneity between groups was used to compare the presence of lesions among patient groups. RESULTS: Lesions of RN, SN and PAG were found in all patient groups, with frequency from 57.5% to 86.5%. Significant between-group differences for all these regions were found. No difference was found between migraine patients with and without aura. Compared with MS patients without migraine, MS patients with migraine had more significant involvement of the SN (p=0.02) and RN (p<0.0001). Compared with migraine patients, MS patients with migraine had more significant involvement of the SN and PAG (p ranging from 0.009 to 0.02). CONCLUSIONS: T2-visible lesions in the brainstem are frequent in patients with migraine, but do not seem to be associated with the presence of aura. Demyelinating lesions in the RN, SN and PAG might be among the factors responsible for the presence of migraine in patients with MS.

Cost-utility analysis of intravenous immunoglobulin and prednisolone for chronic inflammatory demyelinating polyradiculoneuropathy.

The aim of this study was to provide an incremental cost-effectiveness analysis comparing intravenous immunoglobulin (IVIg) and prednisolone treatment for chronic inflammatory demyelinating polyradiculoneuropathy. Patients were recruited to a double-blind randomized crossover trial from nine European centres and received either prednisolone or IVIg during the first 6-week treatment period on which the economic evaluation was based. A societal perspective was adopted in measuring service use and costs, although the costs of lost employment were not included. The main outcome measure in the economic evaluation was the number of quality adjusted life years (QALYs) gained, with change in a 11-point disability scale used to measure clinical outcomes. Service use and quality of life data were available for 25 patients. Baseline costs were controlled for using a bootstrapped multiple regression model. The cost difference between the two treatments was estimated to be euro 3754 over the 6-week period. Health-related quality of life, as measured by the EuroQol EQ-5D instrument, increased more in the IVIg group but the difference was not statistically significant. Using a net-benefit approach it was shown that the probability of IVIg being cost-effective in comparison with prednisolone was 0.5 or above (i.e. was more likely to be cost-effective than cost-ineffective) only if one QALY was valued at over euro 250 000. The cost-effectiveness of IVIg is greatly affected by the price of IVIg and the amount administered. The impact of later side-effects of prednisolone on long-term costs and quality of life are likely to reduce the cost per QALY of IVIg treatment.

Assessment of normal-appearing white and gray matter in patients with primary progressive multiple sclerosis: a diffusion-tensor magnetic resonance imaging study.

BACKGROUND: Diffusion-tensor magnetic resonance imaging is sensitive to the more destructive aspects of multiple sclerosis (MS) evolution occurring outside and within T2-visible lesions and, as a consequence, holds promise for providing a more complete picture of primary progressive (PP) MS-related tissue damage than conventional magnetic resonance imaging. OBJECTIVE: To improve our understanding of PPMS by assessing the extent of occult pathological features in the normal-appearing white and gray matter of the brain using diffusion-tensor magnetic resonance imaging. METHODS: Ninety-six patients with PPMS, 47 patients with secondary progressive (SP) MS, and 44 healthy control subjects were studied. T2-hyperintense and T1-hypointense lesion volumes were calculated, and the volume of the whole brain tissue was measured. Diffusion-tensor magnetic resonance imaging scans were postprocessed and analyzed to obtain the mean diffusivity and fractional anisotropy histograms from the brain and from the normal-appearing white and gray matter in isolation. RESULTS: The mean T2-hyperintense and T1-hypointense lesion volumes were lower in patients with PPMS than in patients with SPMS, while the mean absolute brain volumes were similar in the 2 groups. The average lesion diffusivity was significantly higher in patients with SPMS than in patients with PPMS (P<.001). Histogram-derived metrics of the brain tissue and normal-appearing white and gray matter were significantly different between patients with PPMS and healthy subjects (range, P =.004 to <.001). Average diffusivity values were significantly higher in patients with SPMS than in patients with PPMS for all the tissues studied (range, P =.001 to <.001). Fractional anisotropy histogram-derived quantities did not significantly differ between the 2 patient groups (range, P =.94 to.03). CONCLUSION: This study confirms that, in patients with PPMS, normal-appearing white and gray matter are not spared by disease-related pathological processes, although they are affected to a lesser degree than in patients with SPMS.

Assessment, pathophysiology and treatment of fatigue in multiple sclerosis.

This review will update current views of the physiopathology and treatment of fatigue in multiple sclerosis. Fatigue is a common symptom in multiple sclerosis, being reported by about a third of the patients. For many of them it is the most disabling symptom, with negative consequences on working activity and daily life. There are no objective measures of fatigue which is essentially based on subjective complaints. Even if fatigue may be influenced by motor disturbances and depression, it is largely independent from both. Peripheral mechanisms, such as muscular disuse and deconditioning, joint abnormalities and metabolic changes of muscular fibers, have very little role in multiple sclerosis fatigue. All the available data indicate that fatigue is a 'central' phenomenon, due to multiple causes. Neurophysiological studies revealed an impairment of volitional drive to the descending motor pathways and functional imaging studies fund a selective involvement of frontal cortex and basal ganglia. Therefore, a dysfunction of the circuits between thalamus, basal ganglia and frontal cortex, affected by the multiple sclerosis lesions and/or disturbed in their function by the products of inflammation could be the substrate of fatigue. No specific treatments are available - management strategies include medications, exercise and behavioral therapy - in most cases a combined approach is suitable. Enhancers of vigilance, like amantadine and modafinil, were shown to be effective in class I and II trials, however their effects are modest. Aminopyridines may indirectly influence fatigue by reducing nerve conduction block in motor fibers. Some recent studies suggest the positive effects of drugs on fatigue may be via reducing the inflammatory activity, such as for glatiramer acetate.