Quantitative functional measures in MS: what is a reliable change?

The EDSS-Plus, an improved endpoint for disability progression in secondary progressive multiple sclerosis

BACKGROUND

The Expanded Disability Status Scale (EDSS) has wide scientific and regulatory precedent but limited ability to detect clinically relevant disability progression in secondary progressive multiple sclerosis (SPMS) patients, partly due to a lack of meaningful measurement of short-distance ambulatory and upper-extremity function.

OBJECTIVE

To present a rationale for a composite endpoint adding the timed 25-foot walk (T25FW) and 9-Hole Peg Test (9HPT) to EDSS for SPMS disability progression assessment.

METHODS

Using the International Multiple Sclerosis Secondary Progressive Avonex Clinical Trial (IMPACT) placebo arm ( n = 215) data, we analyzed disability progression using a novel progression endpoint, "EDSS-Plus," defined as progression on ⩾1 of 3 components (EDSS, T25FW, and/or 9HPT) confirmed ⩾24 weeks apart and with a ⩾20% minimum threshold change for T25FW and 9HPT.

RESULTS

Over 2 years, subjects classified as T25FW, 9HPT (dominant hand), or 9HPT (non-dominant hand) progressors worsened on average by 103.4%, 69.0%, and 59.2%, respectively, while non-progressors' times remained largely unchanged. Using EDSS-Plus, 59.5% of the patients had 24-week confirmed disability progression versus 24.7% (EDSS), 41.9% (T25FW), and 34.4% (9HPT (either hand)) on each component alone.

CONCLUSION

The 24-week confirmed minimum worsening of ⩾20% for T25FW and 9HPT clearly separates SPMS progressors from non-progressors. We propose that EDSS-Plus may represent an improved endpoint to identify SPMS disability progression.

SaGA S, the Short and Graphic A bility Score: an alternative scoring method for the motor components of the Multiple Sclerosis Functional C omposite

The timed performances of the 10-m timed walk (TMTW) and the nine-ho le peg test (NHPT) of 881 consecutive patients with multiple sclerosis (MS) undergoing a rehabilitation stay, were expressed as a logarithmic function of time in two subscores to form a composite score called the Short and G raphic A bility Score (SaGA S). The subscores (sS) were constructed in such a way that any interval of 0.5 unit corresponds to a change of 25% in the tests. The SaGA S was computed as the mean of four subscores: SaGAS=(2×2-TMTWsS+NHPTsS right hand+NHPTsS left hand). With the aid of a nomogram, the timed values of the tests are easily transformed into the corresponding subscores, which are then displayed graphically to facilitate follow-up over time. The correlation coefficients between the SaGA S and the two motor components of the MS Functional C omposite (MSFC) (r =0.987), the Expanded Disability Status Scale (EDSS)(r = -0.83), the Nottingham EADL Index (r =0.80) and the Rivermead Mobility Index (RMI) (r =0.90) were all statistically significant (P B-0.001), supporting the validity of the measure. SaGA S had a similar sensitivity to the RMI, but was significantly more sensitive than the EDSS in detecting changes occurring during the rehabilitation stay (14.9% versus 5.0%; P B-0.001) and over a one-year follow-up (35.3% versus 19.7%; P B-0.001). C ompared with the motor components of the MSFC, with which it shares several features, SaGA S has several advantages: it does not depend on the stratification of the study population; it does not skew the results of the NHPT towards improvement at the lower end; and it offers an independent assessment of both hands. SaGA S is a simple, intuitive, nonphysician-based measure, which could provide consistent scoring in future clinical trials.

The patient's perception of a (reliable) change in the Multiple Sclerosis Functional C omposite

Objective: To prospectively character ize the relation between two-year changes in functional impairment as measured by the Multiple Sclerosis Functio nal C omposite (MSFC) and changes in patient perceived disability as measured by the Guy’s Neurological Disability Scale (GNDS). Methods: O ne hundred and eighty-eight patients with multiple sclerosis (MS) were recruited at our outpatient clinic. Impairment and disability were assessed using the MSFC and G NDS at baseline and follow-up. Longitudinal correlations were studied between changes in MSFC and GNDS and their corresponding components. We also studied changes in G NDS in relation to what can be classified as a reliable change in MSFC; for example, 20% change in each MSFC component or a change of 0.5 in total MSFC score. In addition, we studied the change in total number of GNDS subcategories with a score of 3 or higher in relation to the predefined MSFC changes, these subcategories being indicative of the requirement for help by another person. Results: Despite good cross-sectional correlations between MSFC and GNDS, no significant correlation was found between longitudinal changes in MSFC and GNDS. A nalysing the change in GNDS in relation to the predefined MSFC changes shows that G NDS changes are nicely rank ordered when more stringent definitions of reliable change were applied. In addition, analysing the number of G NDS subcategories scored 3 or higher indicate that there is a profile of worsening on the MSFC being associated with increase in the amount of help required from others. Conclusion: O ur longitudinal data suggest that a reliable change is associated with a likewise change in patient perceived disability, the smallest reliable change being identified by at least 20% change in each MSFC component.

Clinical response and tolerability of fampridine in clinical practice

Background: Gait disorder is very prevalent in multiple sclerosis. After 15 years of disease progression, 50% of patients need assistive devices for walking. Materials & methods: We performed a multicenter observational study, including multiple sclerosis patients with an Expanded Disability Status Scale score between 4.0 and 7.0, normal kidney function and no previous history of seizures. Results: The study sample comprised 138 patients with average age of 50.3 years median Expanded Disability Status Scale of 6.0. After treatment, a significant reduction was observed in both the Timed 25-Foot Walk test (baseline, 20.3 s; 14 days, 13.2 s; p < 0.001; 3 months, 12.1 s; p < 0.001) and the 12-Item Multiple Sclerosis Walking Scale score (baseline, 82.3; 14 days, 59.4; p < 0.001; 3 months, 57.2; p < 0.001). Adverse events were recorded in 39.9% of patients.

Oral fingolimod in primary progressive multiple sclerosis (INFORMS): a phase 3, randomised, double-blind, placebo-controlled trial

BACKGROUND

No treatments have been approved for primary progressive multiple sclerosis. Fingolimod, an oral sphingosine 1-phosphate receptor modulator, is effective in relapse-onset multiple sclerosis, but has not been assessed in primary progressive multiple sclerosis. We assessed the safety and efficacy of fingolimod in patients with primary progressive multiple sclerosis.

METHODS

In INFORMS, a multicentre, double-blind, placebo-controlled parallel-group study, patients with primary progressive multiple sclerosis recruited across 148 centres in 18 countries were randomly allocated (1:1) with computer-generated blocks to receive oral fingolimod or placebo for at least 36 months and a maximum of 5 years. Patients were initially assigned to fingolimod 1·25 mg per day or placebo (cohort 1); however, after a protocol amendment on Nov 19, 2009, patients were switched in a masked manner to fingolimod 0·5 mg, whereas those on placebo continued on matching placebo. From then onwards, patients were assigned to receive fingolimod 0·5 mg/day or placebo (cohort 2). Key inclusion criteria were age 25-65 years, clinical diagnosis of primary progressive multiple sclerosis, 1 year or more of disease progression, and two of the following criteria: positive brain MRI; positive spinal cord MRI; or positive cerebrospinal fluid. Additional eligibility criteria included disease duration of 2-10 years and objective evidence of disability progression in the previous 2 years. Patients and study investigators were masked to group assignment. We used a novel primary composite endpoint based on change from baseline in Expanded Disability Status Scale (EDSS), 25' Timed-Walk Test, or Nine-Hole Peg Test to assess time to 3-month confirmed disability progression in study participants treated for at least 3 years. All randomised patients took at least one dose of study drug. The primary efficacy analysis included all patients in cohort 2 and those assigned to placebo in cohort 1. The safety analysis included all patients in cohorts 1 and 2. This study is registered with ClinicalTrials.gov, number NCT00731692. The study is now closed.

FINDINGS

970 patients were randomly assigned between Sept 3, 2008, and Aug 30, 2011 (147 to fingolimod 1·25 mg and 133 to placebo in cohort 1; 336 to fingolimod 0·5 mg and 354 to placebo in cohort 2). The efficacy analysis set (n=823) consisted of 336 patients randomly allocated to fingolimod 0·5 mg and 487 to placebo. Baseline characteristics were similar across groups and representative of a primary progressive multiple sclerosis population (48% women, mean age 48·5 years [SD 8·4], mean EDSS 4·67 [SD 1·03], 87% free of gadolinium-enhancing lesions). By end of study, 3-month confirmed disability progression had occurred in 232 and 338 patients in the fingolimod and placebo groups, respectively, resulting in Kaplan-Meier estimates of 77·2% (95% CI 71·87-82·51) of patients in the fingolimod group versus 80·3% (73·31-87·25) of patients in the placebo group (risk reduction 5·05%; hazard ratio 0·95, 95% CI 0·80-1·12; p=0·544). Safety results were generally consistent with those of studies of fingolimod in patients with relapse-onset multiple sclerosis. Lymphopenia occurred in 19 (6%) patients in the fingolimod group versus none in the placebo group, bradycardia in five (1%) versus one (<1%), and first-degree atrioventricular block in three (1%) versus six (1%). Serious adverse events occurred in 84 (25%) patients in the fingolimod group and 117 (24%) in the placebo group, including macular oedema in six (2%) versus six (1%), and basal-cell carcinoma in 14 (4%) versus nine (2%).

INTERPRETATION

The anti-inflammatory effects of fingolimod did not slow disease progression in primary progressive multiple sclerosis. Therapeutic strategies for primary progressive multiple sclerosis might need different approaches to those used for relapse-onset multiple sclerosis.

FUNDING

Novartis Pharma AG.

Treatment Optimization in Multiple Sclerosis

The treatment of multiple sclerosis has finally become possible with the advent of the current disease-modifying therapies (DMTs) that have had a significant impact on those living with this disease. Though demonstrating clear efficacy on a number of short-term outcome measures, unfortunately, these agents are not “cures” and many patients with multiple sclerosis continue to experience disease activity in spite of treatment. Clinicians are becoming more comfortable initiating therapy with DMTs, but it is now important to focus attention on monitoring the results of the chosen therapy and deciding whether or not a patient is responding well to treatment. At present, however, clinicians lack criteria for defining optimal versus suboptimal responses to DMTs as well as evidence-based guidelines on how to improve treatment outcomes. Using a recently published model as a framework, The Canadian Multiple Sclerosis Working Group developed practical recommendations on how neurologists can assess the status of patients on DMTs and decide when it may be necessary to modify treatment in order to optimize outcomes. The Canadian Multiple Sclerosis Working Group's recommendations are based on monitoring relapses, neurological progression and MRI activity. Other possible causes of suboptimal treatment responses or treatment failure are also considered.

Quantitative sensory and motor measures detect change overtime and correlate with walking speed in individuals with multiple sclerosis

BACKGROUND

Impairments of sensation, strength, and walking are common in multiple sclerosis (MS). The relationship among these abnormalities and how they change over time remains unclear.

OBJECTIVE

To determine the extent that quantitative lower extremity sensory and motor measures detect abnormalities over time, relate to global disability, and to walking speed in individuals with MS.

METHODS

This prospective, longitudinal analysis evaluated 136 MS subjects. Measures included measures of leg strength, sensation, the Expanded Disability Status Scale(EDSS) and timed 25-foot walk test (T25FW). Mixed effects regression models were used.

RESULTS

Our cohort׳s mean age is 44.3±10.8 years (mean±SD), EDSS score range 0–7.5, 66% were females, and follow-up time was 2.1±1.2 years. Strength significantly changed over time; the RRMS group demonstrated the greatest changes in ADF (3.3 lbs/yr) while the PPMS group showed significant HF changes (−2.1 lbs/yr). Walking speed was affected most by HF, especially in the weakest individuals (HF<20 lbs); T25FW increased by 0.20 s for each 1 lb loss (p=0.001). Likewise T25FW changed by 0.19 s for each 1 lb change in ADF (p<0.01).

CONCLUSION

Quantitative measures detected changes in sensation and strength over time, despite a stable respective functional systems scores of the EDSS. Quantitative measurement tools may improve the sensitivity of disability measures in MS and further investigation of these tools as outcomes in future clinical trials of rehabilitative and neuroreparative interventions is warranted.

Timed walk as primary outcome measure of treatment response in clinical trials for HTLV-1-associated myelopathy: a feasibility study

BACKGROUND

To advance the treatment of HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), randomised controlled therapeutic studies with appropriate and sensitive outcomes are reuired. One candidate outcome is the 10-metre walk test (10MWT), a patient-centred, simple and functional measure. To calculate sample size based on 10MWT as the primary outcome, variability within and between subjects must be known.

METHODS

Data on 10MWT from 76 patients with HAM/TSP were prospectively collected from four specialist centres in Brazil, Japan, USA and UK. Data, collected at two time points, 6 months apart, were log transformed and subjected to analysis of covariance.

RESULTS

Baseline mean (standard deviation = SD), median 10MWT were 23.5 (18.9), 16.3 s/10 m and at 6 months 24.9 (23.9), 16.4 s/10 m. The mean (SD) % increase in walk time was 5.74 % (28.2 %). After logarithmic transformation, the linear correlation between baseline and 24 weeks 10MWT was r = 0.938. Using these data, it was determined that a randomised controlled trial with 30 participants per group would have 90 % power to detect a 19 % decrease or a 23 % increase in 10MWT.

CONCLUSIONS

The intra-patient variability of 10MWT is relatively small in HAM/TSP over 6 months. 10MWT is a feasible outcome measure for a clinical trial in HAM/TSP. To our knowledge, this is the first ever recommendation for the sample size required for trials in HAM/TSP patients.

Detection of postural sway abnormalities by wireless inertial sensors in minimally disabled patients with multiple sclerosis: a case-control study

Background

Common clinical neurological exams can be insensitive to balance and mobility impairment at the early stages of multiple sclerosis (MS) and may not correspond with patient reports. Instrumented measurement of standing postural sway with inertial motion sensors may provide sensitive measures of balance impairment and better correspond with patient reports.

Methods

While wearing wireless inertial sensors, 20 subjects with MS – Expanded Disability Status Scale of less than 3.0 and a Timed 25 Foot Walk of 5 sec or less – and 20 age- and sex-matched control subjects stood with eyes open and eyes closed on a foam surface. Forty-six outcome measures of postural sway were derived. A stepwise logistic regression model determined which measures of instrumented sway provide independent predictors of group status. Subjects with MS also completed the Activities-Specific Balance Confidence (ABC) scale and the 12-Item MS Walking Scale (MSWS-12) as measures of subject-reported balance and mobility impairment.

Results

The regression model identified medio-lateral sway path length and medio-lateral range of sway acceleration amplitude, each in the eyes-open condition, as the only two significant independent predictors to differentiate subjects with MS from those without MS (model chi-squared = 34.55, p < 0.0001): accuracy = 87.5 %, positive likelihood ratio = 6 (2.09–17.21), negative likelihood ratio = 0.12 (0.03–0.44). Range of sway acceleration amplitude significantly correlated with both ABC (Spearman’s r = −0.567, p = 0.009) and MSWS-12 scores (Spearman’s r = −0.590, p = 0.006).

Conclusions

Postural sway abnormalities in subjects with MS who are minimally disabled were detected using wireless inertial sensors and may signify a superior sensitivity to identify balance impairment prior to developing clinically evident disability or impaired gait speed. Further study is needed to confirm the clinical significance and predictive value of these objectively identified balance impairments.

Interferon Beta-1a (AVONEX®) as a Treatment Option for Untreated Patients with Multiple Sclerosis (AXIOM): A Prospective, Observational Study

The efficacy and safety of first-line disease-modifying therapies (DMT) for relapsing-remitting multiple sclerosis (RRMS) has been demonstrated in pivotal, randomized trials, but these studies do not reflect the routine care setting where treatment gaps or switches are common. The Avonex as Treatment Option for Untreated MS Patients (AXIOM) trial assessed the efficacy of newly-initiated intramuscular interferon beta-1a (IM IFNb-1a) after a treatment-free interval, with particular consideration of the previous course of disease and therapy. The AXIOM trial was an open, 12-month, observational, non-interventional study with a retrospective and a prospective part conducted in Germany. RRMS patients with a treatment-free interval of at least three months were included and treated with IFNb-1a for up to 12 months. Relapse rate, disability progression, injection-related parameters and quality of life observed during the prospective part were compared with retrospectively-collected data. Two hundred and thirty five RRMS patients participated in AXIOM. The mean relapse rate decreased from 1.1 in the three months before baseline to 0.2 per quarter during the twelve-month observational period; the Multiple Sclerosis Functional Composite score improved during twelve months of IM IFNb-1a treatment, while the Expanded Disability Status Scale score did not change over the course of this study. Compared to previous DMTs (IM IFNb-1a, subcutaneous IFNb-1a (SC IFNb-1a), SC IFNb-1b, glatiramer acetate), the patients experienced less injection site reactions and flu-like symptoms, with a stated improved quality of life. IM IFNb-1a was effective and well accepted in RRMS patients with no or discontinued previous therapy. These results from the routine care setting may inform optimization of DMT treatment in RRMS, but need confirmation in further studies.

Evaluation of Dalfampridine Extended Release 5 and 10 mg in Multiple Sclerosis: A Randomized Controlled Trial

BACKGROUND

Dalfampridine extended-release (ER) tablets, 10 mg twice daily, have been shown to improve walking in people with multiple sclerosis. We evaluated the safety and efficacy of dalfampridine-ER 5 mg compared with 10 mg.

METHODS

Patients were randomized to double-blind treatment with twice-daily dalfampridine-ER tablets, 5 mg (n = 144) or 10 mg (n = 143), or placebo (n = 143) for 4 weeks. Primary efficacy endpoint was change from baseline walking speed by the Timed 25-Foot Walk 3 to 4 hours after the last dose. At 40% of sites, 2-week change from baseline walking distance was measured by the 6-Minute Walk test.

RESULTS

At 4 weeks, walking speed changes from baseline were 0.363, 0.423, and 0.478 ft/s (placebo, dalfampridine-ER 5 mg, and dalfampridine-ER 10 mg, respectively [P = NS]). Post hoc analysis of average changes between pretreatment and on-treatment showed that relative to placebo, only dalfampridine-ER 10 mg demonstrated a significant increase in walking speed (mean ± SE): 0.443 ± 0.042 ft/s versus 0.303 ± 0.038 ft/s (P = .014). Improvement in 6-Minute Walk distance was significantly greater with dalfampridine-ER 10 mg (128.6 ft, P = .014) but not with 5 mg (76.8 ft, P = .308) relative to placebo (41.7 ft). Adverse events were consistent with previous studies. No seizures were reported.

CONCLUSIONS

Dalfampridine-ER 5 and 10 mg twice daily did not demonstrate efficacy on the planned endpoint. Post hoc analyses demonstrated significant increases in walking speed relative to placebo with dalfampridine-ER 10 mg. No new safety signals were observed.

Longitudinal changes in self-reported walking ability in multiple sclerosis

Background

Patient-reported outcomes are increasingly used to understand the clinical meaningfulness of multiple sclerosis disability and its treatments. For example, the 12-item Multiple Sclerosis Walking Scale (MSWS-12) measures the patient-reported impact of the disease on walking ability.

Objective

We studied longitudinal changes in walking ability using the MSWS-12 in a cohort of 108 patients with relapsing-remitting multiple sclerosis and moderate-to-severe disability from a single US center cohort study investigating multiple sclerosis symptoms and physical activity.

Methods

The MSWS-12 was completed every 6 months over 2 years together with self-reported measures of disease impact on daily life (Multiple Sclerosis Impact Scale) and walking disability (Patient Determined Disease Steps scale).

Results

The results revealed a high frequency of self-reported changes in walking ability at the individual level, affecting approximately 80% of patients for all four time periods. MSWS-12 scores remained stable at the group level for all four time periods. The magnitude of observed changes at the individual level was higher than the proposed minimal clinically important differences of 4 or 6 points and correlated better with Multiple Sclerosis Impact Scale physical scores than psychological scores, but little with self-reported Patient Determined Disease Steps Scale scores.

Conclusions

This novel finding of frequent fluctuations in self-reported walking ability is new and requires further investigation.

Functional clinical outcomes in multiple sclerosis: Current status and future prospects

For decades, the Expanded Disability Status Scale (EDSS) has been the principal measure of disability in clinical trials in patients with multiple sclerosis (MS) and in clinical practice. However, this test is dominated by effects on ambulation. Composite endpoints may provide a more sensitive measure of MS-related disability through the measurement of additional neurological functions. The MS Functional Composite (MSFC) includes a walking test (25-ft walk) plus tests of upper extremity dexterity (9-hole peg test) and cognitive function (Paced Auditory serial Addition test [PASAT]). Replacing PASAT with the Symbol Digit Modality test, a more sensitive test preferred by patients, may improve the clinical utility of the MSFC. In addition, disease-specific measures of QoL may be used alongside the MSFC (which does not include measurement of QoL). Clinical data suggest that disease-modifying therapies may delay or prevent relapse, and better composite measures will be valuable in the assessment of disease activity-free status in people with MS.

High doses of biotin in chronic progressive multiple sclerosis: a pilot study

BACKGROUND

No drug has been found to have any impact on progressive multiple sclerosis (MS). Biotin is a vitamin acting as a coenzyme for carboxylases involved in key steps of energy metabolism and fatty acids synthesis. Among others, biotin activates acetylCoA carboxylase, a potentially rate-limiting enzyme in myelin synthesis.

OBJECTIVES

The aim of this pilot study is to assess the clinical efficacy and safety of high doses of biotin in patients suffering from progressive MS.

STUDY DESIGN

Uncontrolled, non-blinded proof of concept study

METHODS

23 consecutive patients with primary and secondary progressive MS originated from three different French MS reference centers were treated with high doses of biotin (100-300mg/day) from 2 to 36 months (mean=9.2 months). Judgement criteria varied according to clinical presentations and included quantitative and qualitative measures.

RESULTS

In four patients with prominent visual impairment related to optic nerve injury, visual acuity improved significantly. Visual evoked potentials in two patients exhibited progressive reappearance of P100 waves, with normalization of latencies in one case. Proton magnetic resonance spectroscopy (H-MRS) in one case showed a progressive normalization of the Choline/Creatine ratio. One patient with left homonymous hemianopia kept on improving from 2 to 16 months following treatment׳s onset. Sixteen patients out of 18 (89%) with prominent spinal cord involvement were considered as improved as confirmed by blinded review of videotaped clinical examination in 9 cases. In all cases improvement was delayed from 2 to 8 months following treatment׳s onset.

CONCLUSIONS

These preliminary data suggest that high doses of biotin might have an impact on disability and progression in progressive MS. Two double-blind placebo-controlled trials are on going.

Neurological disability and its association with walking impairment in multiple sclerosis: brief review

SUMMARY 

Neurological disability and walking impairment are two common, co-varying consequences of multiple sclerosis (MS) that can result in substantial patient burden for daily activities and quality of life. Indeed, neurological disability and walking impairment are driven by pathological changes in the central nervous system, and measurement of walking function is a common method of monitoring the progression of disease and neurological disability. The existing data indicate that the presence of walking impairments range from performance through real-world outcomes based on comparison of MS versus healthy controls, and walking impairments become worse with increasing severity of neurological disability (i.e., progression). Accordingly, researchers and clinicians have considered both pharmaceutical and rehabilitation approaches for managing walking impairment in MS. Both approaches yield beneficial effects on walking outcomes, although the majority of research has focused on exercise training rather than pharmaceutical interventions. Overall, this underscores the importance of continued efforts toward identifying approaches for preventing, forestalling and restoring walking function in persons with MS across the spectrum of neurological disability and its progression.

A pooled analysis of two phase 3 clinical trials of dalfampridine in patients with multiple sclerosis

BACKGROUND

Two phase 3 clinical trials demonstrated that dalfampridine extended-release 10-mg tablets (D-ER), twice daily, significantly improved walking relative to placebo in patients with multiple sclerosis (MS). The objective of this study was to evaluate the efficacy and safety of D-ER in patients with MS using pooled data from the two phase 3 trials.

METHODS

Data were pooled from the two trials, and D-ER was compared with placebo for timed-walk responder rate, changes in walking speed, and the 12-item Multiple Sclerosis Walking Scale (MSWS-12). Response rates were evaluated with respect to demographic and clinical characteristics.

RESULTS

D-ER had a significantly higher proportion of timed-walk responders relative to placebo (37.6% vs. 8.9%; P < .0001). The responder rate was independent of age, gender, race, body-mass index, type of MS, duration of MS, baseline Expanded Disability Status Scale score, baseline walking speed, and concomitant use of immunomodulatory therapies. Significant improvements were observed in walking speed and in MSWS-12 score for the pooled D-ER group compared with placebo. The safety profile was consistent with the individual studies; no new safety or tolerability concerns were identified.

CONCLUSIONS

D-ER demonstrated efficacy for the improvement of walking in patients with MS; response was independent of demographic and clinical characteristics.

Neuromuscular adaptations to long-term progressive resistance training translates to improved functional capacity for people with multiple sclerosis and is maintained at follow-up

Background:

Progressive resistance training (PRT) is acknowledged to effectively improve muscle strength for people with multiple sclerosis (PwMS), but diverging results exist regarding whether such improvements translates to improved functional capacity, possibly relating to insufficient duration and/or intensity in some previous studies.

Objective:

The purpose of this study was to evaluate potential changes in functional capacity and neuromuscular function after 24 weeks of supervised PRT, and whether improvements are maintained after an additional 24 weeks of self-guided exercise.

Methods:

This study was a randomised controlled trial, with a training group and a waitlist group undergoing supervised PRT for 24 weeks initially or after 24 weeks of habitual lifestyle, respectively. Functional capacity, isometric muscle strength of knee extensors and flexors, neural drive and thigh muscle cross-sectional area was measured at baseline, after 24 and 48 weeks.

Results:

The training group significantly improved neuromuscular function of the knee extensors and flexors, which translated to improvements in functional capacity. Furthermore, the improved functional capacity was maintained after 24 weeks of self-guided physical activity. The waitlist group produced similar patterns of changes after PRT.

Conclusion:

Compelling evidence is provided, that PRT performed over sufficiently long periods, improves functional capacity, likely due to neuromuscular adaptations.

Treatment Optimization in MS: Canadian MS Working Group Updated Recommendations

The Canadian Multiple Sclerosis Working Group (CMSWG) developed practical recommendations in 2004 to assist clinicians in optimizing the use of disease-modifying therapies (DMT) in patients with relapsing multiple sclerosis. The CMSWG convened to review how disease activity is assessed, propose a more current approach for assessing suboptimal response, and to suggest a scheme for switching or escalating treatment. Practical criteria for relapses, Expanded Disability Status Scale (EDSS) progression and MRI were developed to classify the clinical level of concern as Low, Medium and High. The group concluded that a change in treatment may be considered in any RRMS patient if there is a high level of concern in any one domain (relapses, progression or MRI), a medium level of concern in any two domains, or a low level of concern in all three domains. These recommendations for assessing treatment response should assist clinicians in making more rational choices in their management of relapsing MS patients.

Addressing the regulatory and scientific challenges in multiple sclerosis – a statement from the EU regulators

Improving and facilitating the process of making new drugs available to patients with multiple sclerosis (MS) requires cooperation among the regulators and other stakeholders. This cooperation will also positively contribute towards developing guidelines of the highest quality in medical, regulatory and scientific aspects. This would be beneficial both in areas that require further guideline development, but also in fields where existing guidance should be adapted to take into account evolution in science. Considering the input from all stakeholders, the European Medicines Agency confirmed its intention to update the relevant guideline and apply a flexible approach towards new drug development strategies in MS. This article is the first official position from the EU regulators, presenting the main changes to be expected in the guidance document.

Development of dalfampridine, a novel pharmacologic approach for treating walking impairment in multiple sclerosis

Walking impairment is a clinical hallmark of multiple sclerosis (MS). Dalfampridine-ER, an extended-release formulation of dalfampridine (also known by its chemical name, 4-aminopyridine, and its international nonproprietary name, fampridine), was developed to maintain drug plasma levels within a narrow therapeutic window, and assessed for its ability to improve walking in MS. The putative mechanism of action of dalfampridine-ER is restoration of axonal conduction via blockade of the potassium channels that become exposed during axonal demyelination. Two pivotal phase III clinical trials demonstrated that dalfampridine-ER 10-mg tablets administered twice daily improved walking speed and patient-reported perceptions of walking in some patients. Dalfampridine-ER was generally well tolerated, and, at the approved dose, risk of seizure was neither elevated relative to placebo nor higher than the rate in the MS population. Dalfampridine-ER (AMPYRA®) was approved in the United States for the treatment of walking in patients with MS as demonstrated by an increase in walking speed. The use of the dalfampridine-ER is contraindicated in patients with a history of seizure. It is the first pharmacologic therapy for this indication and has been incorporated into clinical management of MS.

Factors associated with clinically significant increased walking time in multiple sclerosis: results of a survival analysis of short-term follow-up data from a clinical database

BACKGROUND

Because multiple sclerosis (MS) is variable and unpredictable, if symptom worsening could be predicted, patients may feel better prepared to manage changes in function.

OBJECTIVE

The objective of this paper is to study the prediction of walking impairment in MS.

METHODS

We retrieved data for all MS patients at our center (2008-2009), including baseline and follow-up timed 25-foot walk (T25FW) times. We assessed the incidence of ≥20% worsening in T25FW by developing two survival models: (1) disease course and (2) Multiple Sclerosis Performance Scales (MSPS) score. The outcome was days until ≥20% worsening in T25FW. Covariates were disease subtype, years since diagnosis, Patient Health Questionnaire-9 (PHQ-9) score, and demographics. Data were interval censored; missing data were handled with multiple imputation.

RESULTS

Of 1544 patients, 309 (20%) experienced ≥20% worsening T25FW. For disease course, time to worsening was significantly shorter for secondary progressive vs. relapsing-remitting disease (p < 0.001). For MSPS, patients with lower baseline MSPS scores progressed more slowly (p = 0.001). In both models, sex, baseline T25W, and time since diagnosis were significantly associated with worsening. In the disease course model, PHQ 9 score may be related to worsening (p = 0.07).

CONCLUSION

These findings suggest factors associated with worsening in T25FW and a potential approach to establishing indicators associated with clinically significant change.

Detecting clinically-relevant changes in progressive multiple sclerosis

OBJECTIVE

To investigate which changes in different clinical outcome measures contribute most to increased disease impact, as reported by the patient, in progressive multiple sclerosis (MS).

METHODS

From a cohort of prospectively-followed MS patients, we selected progressive patients with two visits, 4-6 years apart. We assessed long-term changes on the Expanded Disability Status Scale (EDSS), Timed 25-Foot Walk (T25FW), 9-Hole Peg Test (9HPT) and Guy's Neurological Disability Scale (GNDS). We defined the presence or absence of clinically meaningful change by using the Multiple Sclerosis Impact Scale (MSIS-29) as an anchor measure. We also studied change on recently identified sub-scales of GNDS.

RESULTS

Change on GNDS (especially the spinal-plus subscale) contributed most to increased disease impact. Also change on the T25FW contributed largely. Specific profiles of change in T25FW and MSIS seemed to exist (generally, a lower increase in disease impact in patients with longer disease duration and higher baseline impact/disability). In some patients a dissociation existed between increased impact, according to the MSIS-29, and objective physical worsening of the T25FW.

CONCLUSION

These results support using GNDS (particularly the spinal-plus domain) and T25FW in outcome measurement in progressive MS. We suggest there is a relation between baseline clinical characteristics and an increased impact at follow-up. This may have implications for patient selection in trials for progressive MS.

Sustained-release fampridine (4-aminopyridine) in multiple sclerosis: efficacy and impact on motor function

Objective

The aim of this study was to determine the efficacy of sustained-release fampridine (4-aminopyridine) in veterans with multiple sclerosis (MS) with limited ambulatory ability, and its impact on motor function in an outpatient setting.

Design

Retrospective.

Setting

Tertiary referral center [Veterans Affairs (VA) Medical Center].

Participants

Veterans; 20 MS patients were prescribed dalfampridine (10 mg twice daily) due to their difficulty with walking based on patient and caregiver report and clinician impression of change in the ability to ambulate based on prior 10-meter (10M) and 2-minute walk tests (2MWTs).

Intervention

Not applicable.

Main Outcome Measures

The primary outcome measures were mean changes in walking speed (10M walk test), walking distance (2MWT), and Total Functional Independence Measure (TFIM). Improvement of >20 % in walking speed was indicated as a clinically meaningful change.

Results

Treatment with dalfampridine resulted in significant improvement in walking speed and endurance (p < 0.05). Walking speed increased by 33 % and walking endurance by 31 %, representing clinically meaningful improvement. This change was not influenced by change in muscle tone. This improvement in mobility was associated with a clinically significant change in motor function. Adverse effects, including insomnia, dizziness, and headache, were experienced by five patients who discontinued the medication after a minimum of 4 weeks.

Conclusion

Treatment with dalfampridine resulted in clinically relevant improvements in walking speed and endurance in MS patients with limited ambulation and helped improve their motor function.

Electronic supplementary material

The online version of this article (doi:10.1007/s40268-013-0020-x) contains supplementary material, which is available to authorized users.

Composite end points to assess delay of disability progression by MS treatments

Background:

The Expanded Disability Status Scale (EDSS) has low sensitivity and reliability for detecting sustained disability progression (SDP) in multiple sclerosis (MS) trials.

Objective:

This study evaluated composite disability end points as alternatives to EDSS alone.

Methods:

SDP rates were determined using 96-week data from the Olympus trial (rituximab in patients with primary progressive MS). SDP was analyzed using composite disability end points: SDP in EDSS, timed 25-foot walk test (T25FWT), or 9-hole peg test (9HPT) (composite A); SDP in T25FWT or 9HPT (composite B); SDP in EDSS and (T25FWT or 9HPT) (composite C); and SDP in any two (EDSS, T25FWT, and 9HPT) (composite D).

Results:

Overall agreements between EDSS and other disability measures in defining SDP were 66%−73%. Composite A showed similar treatment effect estimate versus EDSS alone with much higher SDP rates. Composite B, C, and D all showed larger treatment effect estimate with different or similar SDP rates versus EDSS alone. Using composite A (24-week confirmation only), B, C, or D could reduce sample sizes needed for MS trials.

Conclusion:

Composite end points including multiple accepted disability measures could be superior to EDSS alone in analyzing disability progression and should be considered in future MS trials.

Systematic literature review and validity evaluation of the Expanded Disability Status Scale (EDSS) and the Multiple Sclerosis Functional Composite (MSFC) in patients with multiple sclerosis

BACKGROUND

There are a number of instruments that describe severity and progression of multiple sclerosis and they are increasingly used as endpoints to assess the effectiveness of therapeutic interventions. We examined to what extent the psychometric properties of two accepted instruments--EDSS and MSFC--meet methodological standards and the value they have in clinical trials.

METHODS

We conducted a systematic literature search in relevant databases [MEDLINE (PubMed), ISI Web of Science, EMBASE, PsycINFO & PSYNDEX, CINAHL] yielding 3,860 results. Relevant full-text publications were identified using abstract and then full-text reviews, and the literature was reviewed.

RESULTS

For evaluation of psychometric properties (validity, reliability, sensitivity of change) of EDSS and MSFC, 120 relevant full-text publications were identified, 54 of them assessed the EDSS, 26 the MSFC and 40 included both instruments. The EDSS has some documented weaknesses in reliability and sensitivity to change. The main limitations of the MSFC are learning effects and the z-scores method used to calculate the total score. However, the methodological criterion of validity applies sufficiently for both instruments.For use in clinical studies, we found the EDSS to be preferred as a primary and secondary outcome measure in recent studies (50 EDSS, 9 MSFC).

CONCLUSIONS

Recognizing their strengths and weaknesses, both EDSS and MSFC are suitable to detect the effectiveness of clinical interventions and to monitor disease progression. Almost all publications identify the EDSS as the most widely used tool to measure disease outcomes in clinical trials. Despite some limitations, both instruments are accepted as endpoints and neither are discussed as surrogate parameters in identified publications. A great advantage of the EDSS is its international acceptance (e.g. by EMA) as a primary endpoint in clinical trials and its broad use in trials, enabling cross-study comparisons.

Assessing upper limb function in multiple sclerosis

The need to fully assess upper limb function in multiple sclerosis (MS) has become increasingly clear with recent studies revealing a high prevalence of upper limb dysfunction in persons with MS leading to increased dependency and reduced quality of life. It is important that clinicians and researchers use tailored outcome measures to systematically describe upper limb (dys)function and evaluate potential deterioration or improvement on treatment. This topical review provides a comprehensive summary of currently used upper limb outcome measures in MS, classified according to the levels of the International Classification of Functioning (ICF). The clinical utility, strengths, weaknesses and psychometric properties of common upper limb outcome measures are discussed. Based on this information, recommendations for selecting appropriate upper limb outcome measures are given. The current shortcomings in assessment which need to be addressed are identified.

Upper limb assessment in multiple sclerosis: a systematic review of outcome measures and their psychometric properties

OBJECTIVE

To provide an overview of applied upper limb outcome measures in multiple sclerosis (MS) according to the International Classification of Functioning, Disability and Health (ICF) levels and to review their psychometric properties in MS.

DATA SOURCES

PubMed and Web of Knowledge.

STUDY SELECTION

Articles published until June 2013 were selected when written in English, published in the last 25 years, peer reviewed, including >5 persons with MS, and including standardized clinical upper limb outcome measures. Included articles were screened based on title/abstract and full text by 2 independent reviewers. In case of doubt, feedback from a third independent reviewer was obtained. Additionally, references lists were checked for relevant articles. Of the articles, 109 met the selection criteria and were included for data extraction.

DATA EXTRACTION

All reported clinical upper limb outcome measures were extracted from the included studies and classified according to the ICF levels by 2 independent reviewers. In addition, available psychometric properties (reliability, validity, responsiveness) in MS were summarized and discussed.

DATA SYNTHESIS

A diversity of outcome measures assessing impairments on the body functions and structures level (n=33), upper limb capacity (n=11), and performance (n=8) on the activity level were extracted from 109 articles. Hand grip strength and the nine-hole peg test (NHPT) were the most frequently used outcome measures. However, multiple outcome measures are necessary to encapsulate the multidimensional character of the upper limb function. The psychometric properties were insufficiently documented for most of the outcome measures, except for the NHPT.

CONCLUSIONS

The results of this review may help with the selection of appropriate outcome measures and may guide future research regarding the psychometric properties in MS.

Clinically meaningful performance benchmarks in MS: timed 25-foot walk and the real world

OBJECTIVE

Identify and validate clinically meaningful Timed 25-Foot Walk (T25FW) performance benchmarks in individuals living with multiple sclerosis (MS).

METHODS

Cross-sectional study of 159 MS patients first identified candidate T25FW benchmarks. To characterize the clinical meaningfulness of T25FW benchmarks, we ascertained their relationships to real-life anchors, functional independence, and physiologic measurements of gait and disease progression. Candidate T25FW benchmarks were then prospectively validated in 95 subjects using 13 measures of ambulation and cognition, patient-reported outcomes, and optical coherence tomography.

RESULTS

T25FW of 6 to 7.99 seconds was associated with a change in occupation due to MS, occupational disability, walking with a cane, and needing "some help" with instrumental activities of daily living; T25FW ≥8 seconds was associated with collecting Supplemental Security Income and government health care, walking with a walker, and inability to do instrumental activities of daily living. During prospective benchmark validation, we trichotomized data by T25FW benchmarks (<6 seconds, 6-7.99 seconds, and ≥8 seconds) and found group main effects on 12 of 13 objective and subjective measures (p < 0.05).

CONCLUSIONS

Using a cross-sectional design, we identified 2 clinically meaningful T25FW benchmarks of ≥6 seconds (6-7.99) and ≥8 seconds. Longitudinal and larger studies are needed to confirm the clinical utility and relevance of these proposed T25FW benchmarks and to parse out whether there are additional benchmarks in the lower (<6 seconds) and higher (>10 seconds) ranges of performance.

Recommendations for the use of prolonged-release fampridine in patients with multiple sclerosis (MS)

Prolonged-release fampridine (fampridine PR) is a potassium channel blocker that improves conductivity of signal on demyelinated axons in central nervous system. Fampridine PR has been approved to improve speed of walking in patients with multiple sclerosis. This statement provides a brief summary of data on fampridine PR and recommendations on practical use of the medication in clinical practice, prediction, and evaluation of response to treatment and patient management.

Home-based balance training using the Wii balance board: a randomized, crossover pilot study in multiple sclerosis

OBJECTIVE

To evaluate the effectiveness of a home-based rehabilitation of balance using the Nintendo Wii Balance Board System (WBBS) in patients affected by multiple sclerosis (MS).

METHODS

In this 24-week, randomized, 2-period crossover pilot study, 36 patients having an objective balance disorder were randomly assigned in a 1:1 ratio to 2 counterbalanced arms. Group A started a 12-week period of home-based WBBS training followed by a 12-week period without any intervention; group B received the treatment in reverse order. As endpoints, we considered the mean difference (compared with baseline) in force platform measures (i.e., the displacement of body center of pressure in 30 seconds), 4-step square test (FSST), 25-foot timed walking test (25-FWT), and 29-item MS Impact Scale (MSIS-29), as evaluated after 12 weeks and at the end of the 24-week study period.

RESULTS

The 2 groups did not differ in baseline characteristics. Repeated-measures analyses of variance showed significant time × treatment effects, indicating that WBBS was effective in ameliorating force platform measures (F = 4.608, P = .016), FSST (F = 3.745, P = .034), 25-FWT (F = 3.339, P = .048), and MSIS-29 (F = 4.282, P = .023). Five adverse events attributable to the WBSS training (knee or low back pain) were recorded, but only 1 patient had to retire from the study.

CONCLUSION

A home-based WBBS training might potentially provide an effective, engaging, balance rehabilitation solution for people with MS. However, the risk of WBBS training-related injuries should be carefully balanced with benefits. Further studies, including cost-effectiveness analyses, are warranted to establish whether WBBS may be useful in the home setting.

Estimation of the effect of dalfampridine-ER on health utility by mapping the MSWS-12 to the EQ-5D in multiple sclerosis patients

Background

Trials have not assessed the effect of dalfampridine-extended release (dalfampridine-ER) on health utility. We sought to evaluate the effect of dalfampridine-ER tablets (prolonged-release fampridine in Europe) on health utility in patients with multiple sclerosis (MS) by mapping subjects’ individual item scores from the 12-Item Multiple Sclerosis Walking Scale (MSWS-12) onto the Euroqol 5-Dimension (EQ-5D) health utility index.

Methods

Data from study MS-F203, a randomized trial of dalfampridine-ER tablets, 10 mg twice daily, in patients with MS, were used to calculate the health utility scores with two MSWS-12 to EQ-5D mapping equations (one derived in a North American [NA] registry, the other a United Kingdom [UK] registry). MS-F203 participants were categorized as dalfampridine-ER 20%-responders (achieving ≥20% improvement on the Timed 25-Foot Walk), dalfampridine-ER 20%-nonresponders (<20% improvement), or placebo patients. Mean change in health utility scores from baseline to each double-blind treatment evaluation (visits 3-6 occurring at post-randomization weeks 2, 6, 10, and 14) and each off-drug follow-up evaluation (visits 7-8 occurring at weeks 16 and 18) were calculated and reported as effect sizes (ESs).

Results

Using the NA-derived equation, dalfampridine-ER 20%-responders demonstrated improvement in health utility vs. placebo; starting at week 6 (mean difference in ES = 0.44, p = 0.002) and maintained at weeks 10 (ES = 0.41, p = 0.01) and 14 (ES = 0.71, p < 0.001). These improvements were no longer evident after dalfampridine-ER was discontinued (p > 0.05 at weeks 16 and 18). Dalfampridine-ER 20%-nonresponders did not show improvement vs. placebo at any visit (p > 0.05 for all). When using the UK-derived equation, improvement was seen in dalfampridine-ER 20%-responders vs. placebo at weeks 2, 6, 10, and 14 (ESs = 0.49, 0.55, 0.59, and 0.99; p < 0.03 for all), but not when dalfampridine-ER was discontinued (weeks 16 and 18; p > 0.05 for both). Dalfampridine-ER 20%-nonresponders showed no improvement at any visit (p > 0.05 for all).

Conclusion

Regardless of the equation used, dalfampridine-ER response was associated with an improvement in health utility.

Timed 25-foot walk: direct evidence that improving 20% or greater is clinically meaningful in MS

OBJECTIVE

In this study, we used data from clinical trials of dalfampridine (fampridine outside the United States) to re-examine the clinical meaningfulness of Timed 25-Foot Walk (T25FW) changes.

METHODS

Pooled data were analyzed from 2 phase III randomized placebo-controlled clinical trials of dalfampridine in multiple sclerosis (MS) (n = 533). Walking speed (T25FW) and patient-reported walking ability (MS Walking Scale-12 [MSWS-12]) were measured, concurrently, multiple times before and during treatment. We examined T25FW speed variability within and between visits, correlations of T25FW speed with MSWS-12 score, and changes in MSWS-12 (mean scores, effect sizes) associated with percent T25FW changes.

RESULTS

T25FW speed variability was small (within- and between-visit averages = 7.2%-8.7% and 14.4%-16.3%). Correlations between T25FW and MSWS-12 values were low (-0.20 to -0.30), but relatively stronger between their change values (-0.33 to -0.41). Speed improvements of >20%, and possibly 15%, were associated with clinically meaningful changes in self-reported walking ability using MSWS-12 change score and effect size criteria.

CONCLUSIONS

This study builds on existing research and provides direct evidence that improvements in T25FW speed of ≥ 20% are meaningful to people with MS. The dalfampridine data enabled examinations previously not possible, including spontaneous and induced speed changes, speed change anchored to change in self-reported walking ability, and a profile of speed changes. Results support the T25FW as a clinically meaningful outcome measure for MS clinical trials.

The reliability, precision and clinically meaningful change of walking assessments in multiple sclerosis

BACKGROUND

Assessing walking impairment in those with multiple sclerosis (MS) is common, however little is known about the reliability, precision and clinically important change of walking outcomes.

OBJECTIVE

The purpose of this study was to determine the reliability, precision and clinically important change of the Timed 25-Foot Walk (T25FW), Six-Minute Walk (6MW), Multiple Sclerosis Walking Scale-12 (MSWS-12) and accelerometry.

METHODS

Data were collected from 82 persons with MS at two time points, six months apart. Analyses were undertaken for the whole sample and stratified based on disability level and usage of walking aids. Intraclass correlation coefficient (ICC) analyses established reliability: standard error of measurement (SEM) and coefficient of variation (CV) determined precision; and minimal detectable change (MDC) defined clinically important change.

RESULTS

All outcome measures were reliable with precision and MDC varying between measures in the whole sample: T25FW: ICC=0.991; SEM=1 s; CV=6.2%; MDC=2.7 s (36%), 6MW: ICC=0.959; SEM=32 m; CV=6.2%; MDC=88 m (20%), MSWS-12: ICC=0.927; SEM=8; CV=27%; MDC=22 (53%), accelerometry counts/day: ICC=0.883; SEM=28450; CV=17%; MDC=78860 (52%), accelerometry steps/day: ICC=0.907; SEM=726; CV=16%; MDC=2011 (45%). Variation in these estimates was seen based on disability level and walking aid.

CONCLUSION

The reliability of these outcomes is good and falls within acceptable ranges. Precision and clinically important change estimates provide guidelines for interpreting these outcomes in clinical and research settings.

Repeatability of the timed 25-foot walk test for individuals with multiple sclerosis

OBJECTIVE

The purpose of this study was to determine if there is a practice effect present in the timed 25-foot walk in ambulatory individuals with multiple sclerosis.

DESIGN

Thirty six people (30 women and 6 men) diagnosed with relapsing remitting multiple sclerosis participated in two testing sessions, one week apart. Each participant performed two sequential trials of the timed 25-foot walk test per session and the walk performance was measured with a laser timing system.

RESULTS

We observed improvements in walking speed between the two trials of session one (trial one: 6.42 (0.09) vs. trail two: 5.97 (0.08) seconds, p < 0.001). Within session two, performance remained stable (trial three: 5.71 (0.07) vs. trial four: 5.63 (0.07) seconds, p > 0.05). We also observed a significant improvement in walking speed when averages of the two trials were compared across sessions (session 1: 6.19 (0.09) vs. session 2: 5.67 (0.07) seconds, p < 0.01).

CONCLUSIONS

Based on our results, familiarization of the timed 25-foot walk test improves stability of walk performance scores in ambulatory individuals with relapsing remitting multiple sclerosis.

Single rescuer exertion using a mechanical resuscitation device: a randomized controlled simulation study

OBJECTIVES

The goal of this experimental study was to investigate rescuer exertion when using "Animax," a manually operated hand-powered mechanical resuscitation device (MRD) for cardiopulmonary resuscitation (CPR), compared to standard basic life support (BLS).

METHODS

This was a prospective, open, randomized, crossover simulation study. After being trained, 80 medical students with substantial knowledge in BLS performed one-rescuer CPR using either the MRD or the standard BLS for 12-minute intervals in random order. The main outcome parameter was the heart rate pressure product (RPP) as an index of cardiac work. Secondary outcome parameters were physical exhaustion quantified by the Borg scale (measurement of perceived exertion), Nine Hole Peg Test (NHPT; measurement of fine motor skills), and capillary lactate concentration during testing.

RESULTS

While no significant difference could be found for the RPP, a significantly increased mean heart rate during the final minute of standard BLS compared to the MRD was found (139 ± 22 beats/min vs. 135 ± 26 beats/min, p = 0.027). By contrast, subjective exertion using the MRD was rated significantly higher on the Borg scale (15.1 ± 2.4 vs. 14.6 ± 2.6, p = 0.027). Mean serum lactate concentration was significantly higher when the MRD was used compared to standard BLS (3.4 ± 1.5 mmol/L vs. 2.1 ± 1.3 mmol/L, p ≤ 0.001).

CONCLUSIONS

Use of the MRD leads to a RPP of the rescuers comparable to standard BLS. These findings suggest that there is no clinically relevant reduction of exertion if this MRD is used by a single rescuer. If this kind of MRD is used for CPR, frequent changeovers with a second rescuer should be considered as the guidelines suggest for standard CPR.

The impact of slower walking speed on activities of daily living in patients with multiple sclerosis

AIMS

To identify the relevance and impact of walking speed (WS) over a short distance on activities of daily living (ADLs) in patients with multiple sclerosis (MS).

METHODS

An internet-administered survey of MS patients in four countries was distributed to 605 individuals in 2010. Participants had MS for > 5 years and must have reported difficulty walking as a result of MS. The impact of MS on walking and the effects of WS on ADLs were assessed based upon responses (scored on a scale of 1-10) to five questions and categorised post hoc as: high (8-10), moderate (4-7) or low (1-3) impact/importance.

RESULTS

Of the participants who completed the survey (n = 112), 60% were female patients, 63% were aged ≥ 45 years, and 55% had relapsing-remitting MS. Approximately, half of participants reported a high impact of MS on their general walking ability (46%) and their ability to increase WS over a short distance (55%). Up to 53% of participants reported avoiding ADLs because of concerns about WS; within this cohort, older male patients and patients with secondary-progressive MS were highly represented.

DISCUSSION

These results, which highlight the importance of WS to patients with MS and emphasise the impact of WS on health-related quality of life and ADLs, underscore the importance of clinical measures of WS, such as the timed 25-foot walk, in assessing walking in MS patients.

CONCLUSION

  Walking speed over a short distance has a significant impact on ADLs for patients with MS.

Sustained-release fampridine and the role of ion channel dysfunction in multiple sclerosis

Ion channel dysfunction is an important mechanism that contributes to functional disability and axonal degeneration in multiple sclerosis (MS). Recent studies have revealed that there are complex rearrangements of voltage-gated Na+ channels that occur with acute brain inflammation in MS, with up-regulation of primitive Na+ channel isoforms such as Nav 1.2 during acute inflammation. While these changes may help support neural conduction, increased expression of ‘persistent’ Na+ conductances and altered function of the Na+/K+ pump may contribute to axonal degeneration in MS. Increased expression of K+ channels due to demyelination has also been considered as a contributing factor to conduction failure in MS. Recent phase II and phase III clinical trials have demonstrated improvements in walking speed in patients receiving fampridine SR, a K+ channel blocker. This medication appears to be well-tolerated with a low risk of serious adverse events and provides benefits in both relapsing and progressive forms of MS.

EDSS variability before randomization may limit treatment discovery in primary progressive MS

Background:

Baseline Expanded Disability Status Scale (EDSS) is usually based on a single measurement. Here we evaluated whether using a baseline EDSS derived from two pre-treatment measurements improves the detection of progression events and the ability to demonstrate a therapeutic effect in delaying MS disability progression.

Methods:

Real data from OLYMPUS, a phase II/III randomized, placebo-controlled trial of rituximab in patients with primary progressive multiple sclerosis (PPMS), as well as simulated data were analyzed. Several definitions of baseline EDSS were used to capture sustained disability progression (SDP) events. Variations in the EDSS were estimated by linear mixed-effect models.

Results:

Selecting the higher of two baseline EDSS scores lowered the number of SDP events in both treatment groups, so decreasing sensitivity, and reduced the number of false SDP events, so increasing specificity. Conversely, selecting the lower of two baseline scores increased sensitivity but decreased specificity. Increased power (~7% based on the simulation study) was observed when the average of screening and Week 0 EDSS scores was used for baseline.

Conclusion:

Baseline EDSS derived from two pre-treatment EDSS measurements may enhance the ability of detecting a therapeutic effect in slowing disability progression in PPMS. This strategy could be implemented in future clinical trials of patients with MS.

Social and economic burden of walking and mobility problems in multiple sclerosis

BACKGROUND

Multiple sclerosis (MS) is a chronic progressive neurological disease and the majority of patients will experience some degree of impaired mobility. We evaluated the prevalence, severity and burden of walking and mobility problems (WMPs) in 5 European countries.

METHODS

This was a cross-sectional, patient record-based study involving 340 neurologists who completed detailed patient record forms (PRF) for patients (>18 years) attending their clinic with MS. Patients were also invited to complete a questionnaire (PSC). Information collected included demographics, disease characteristics, work productivity, quality of life (QoL; EuroQol-5D and Hamburg Quality of Life Questionnaire Multiple Sclerosis [HAQUAMS]) and mobility (subjective patient-reported and objectively measured using the timed 25 foot walk test [T25FW]). Relationships between WMPs and disease and other characteristics were examined using Chi square tests. Analysis of variance was used to examine relationships between mobility measures and work productivity.

RESULTS

Records were available for 3572 patients of whom 2171 also completed a PSC. WMPs were regarded as the most bothersome symptom by almost half of patients who responded (43%; 291/683). There was a clear, independent and strong directional relationship between severity of WMPs (subjective and objective) and healthcare resource utilisation. Patients with longer T25FW times (indicating greater walking impairment) were significantly more likely to require additional caregiver support (p < 0.0001), visit a variety of healthcare professionals including their primary care physicians (p = 0.0044) and require more long-term non-disease modifying drugs (p = 0.0001). A similar pattern was observed when subjective reporting of the severity of WMPs was considered. Work productivity was also markedly impacted by the presence of WMPs with fewer patients working full time and a reduction in weekly working hours as T25FW times and the subjective severity of WMPs increased.

CONCLUSIONS

In Europe, WMPs in MS represent a considerable personal and social burden both financially and in terms of quality of life. Interventions to improve mobility could have significant benefits for patients and society as a whole.

Evaluating cognitive outcome measures for MS clinical trials: what is a clinically meaningful change?

Brief cognitive assessments are increasingly emphasized in MS treatment studies and clinical care. While much is known about the reliability of several widely-used neuropsychological tests, interpretation of the changes in individual patients is inadequate. The FDA offers guidance on the issue, as related to patient-reported outcomes. Unfortunately, cognitive ability is only weakly correlated with the frequency and severity of self-reported cognitive problems. In this review, we critically examined the psychometrics of neuropsychological testing in MS, emphasizing statistical and anchor-based approaches to interpreting clinically meaningful change. We suggest that there are two paths forward that should be currently pursued. First, to employ co-primary outcomes, including a brief cognitive test and a clinician or observer's impression on a scale of change, where successful treatment would require showing significant improvement in both measures. Secondly, to work toward showing that when reliable brief cognitive tests are employed, increments of statistically-relevant change would correlate with changes in clinically-relevant anchors (such as vocational disability or clinical relapses with cognitive impairment). The latter goal will allow a more parsimonious and scientifically efficient approach of utilizing only the brief cognitive test as a primary outcome. While some progress has been made in this direction, more research is needed. We are of the opinion that data from both the statistical and clinically meaningful approaches will be necessary to develop valid definitions of meaningful change on cognitive outcome measures, and that it would be best to pursue research using tests that already have well-established reliability and validity.

Revisiting the multiple sclerosis functional composite: proceedings from the National Multiple Sclerosis Society (NMSS) Task Force on Clinical Disability Measures

This article describes proceedings from a meeting of the National Multiple Sclerosis Society (NMSS) Task Force on Clinical Disability Measures (the TF). The TF was appointed by the NMSS Research Programs Advisory Committee with the goal of pooling and analyzing existing datasets to explore the utility of novel disability outcome measures based on the Multiple Sclerosis Functional Composite (MSFC) approach. The TF seeks to determine the suitability of the MSFC approach as a primary clinical outcome measure for registration trials in MS. The TF met in Washington, DC, Dec. 14 and 15, 2011, and provided unanimous support for a collaborative approach involving representatives from academic medicine, the pharmaceutical industry, regulatory agencies, the NMSS and the Critical Path Institute. There was also unanimous agreement that analysis of existing datasets would be useful in making progress toward the objective. The TF placed high value on determining the clinical meaning of individual component measures for the MSFC, and in establishing optimal analysis methods for MSFC so that scores would be more interpretable than the originally recommended z-score method. The background for a collaborative project aimed at developing an improved disability outcome measure is described in this paper.