Clinical manifestation and perceived symptoms of walking-related performance fatigability in persons with multiple sclerosis.

Fatigue and walking difficulties are common impairments and activity limitations in persons with multiple sclerosis (PwMS). Walking fatigability (WF) can be measured by a Distance Walked Index and is defined as a decline in walking distance of 10% or more during the six-minute walking test (6MWT). However, the clinical manifestation and perceived symptoms related to fatigability are still not well documented. Forty-nine PwMS [Expanded Disability Status Scale (EDSS) ≤6] and 28 healthy controls (HC) performed a 6MWT. The perceived severity of 11 common symptoms was rated on a visual analogue scale of 0-10 before, immediately after, and 10, 20 and 30 minutes after the 6MWT by means of the symptom inventory. Short motor impairment screening tests at baseline together with other descriptive measures were performed. Twenty pwMS were categorized in the WF group and were more disabled (EDSS: 4.16 ± 1.41) than the non-walking fatigability group (n = 29, EDSS: 2.62 ± 1.94). PwMS showed exacerbations of several perceived symptoms in MS, where most symptoms returned to baseline within 10 minutes after the walking test. The WF group showed significantly more muscle weakness and gait impairment, together with balance problems, and experienced an increase in spasticity, pain and dizziness after 6MWT. Our findings showed that perceived severity of symptoms are higher in pwMS presenting WF, and increase temporally after the 6MWT. Future research with quantitative measurement during and after walking is recommended.

Measuring walking-related performance fatigability in clinical practice: a systematic review.

INTRODUCTION: Fatigability, a change in performance according to tasks and circumstances, can contribute to walking limitations in daily life. Walking-related fatigability (WF) has been assessed subjectively, but current knowledge on best objective measurement methods is limited. The aim of this study was to provide an overview of objective clinical measurement methods assessing WF in different populations. EVIDENCE ACQUISITION: Articles were searched in Pubmed and Web Of Science by two independent raters. Studies were included when meeting inclusion criteria of measuring WF objectively in a clinical setting, with no exclusion towards any population. Case studies and reviews were not included in the review (systematic review registration number: PROSPERO - CRD42017074121). In total, 28 articles were included. The study populations were older adults (N.=7), multiple sclerosis (N.=14), spinal muscle atrophy (N.=3), osteoarthritis (N.=3), interstitial lung diseases (N.=1), and myasthenia gravis (N.=1). Data about patient characteristics, walking task, WF formula and interpretation (cut-off values and/or psychometric properties) got extracted from included literature. Every included article got checked for quality and risk of bias. EVIDENCE SYNTHESIS: WF was mostly measured during longer walking test such as six-minute walking test (6MWT) and 500 or 400-m walking test, by comparing the first and last minute or lap for spatiotemporal or kinematic changes in well-defined formulas. No gold standard is however available yet given different tasks or outcome measures across study populations. CONCLUSIONS: Longer walking test were most often used, with a preference towards the 6MWT, thereby comparing the changes over the last and first part of the test. Psychometric properties need more documentation before inclusion as experimental outcome.