Factors and strategies affecting motor imagery ability in people with multiple sclerosis: a systematic review

Abstract

BackgroundAlthough growing evidence has shown beneficial effects of motor imagery (MI) training in different populations including people with multiple sclerosis (pwMS), not all patients with neurological diseases may benefit from MI. ObjectivesTo investigate factors and strategies affecting and enhancing MI ability in pwMS. Data sourcesMEDLINE/PubMed, PsycINFO, Cochrane Library, Scopus, EMBASE, EBSCOhost, Web of Science and REHABDATA databases, clinical trials registries, dissertation repositories, study bibliographies and internet search engines were searched through August 2021. Study selectionAny study type but single case studies investigating factors or strategies contributing to MI ability in pwMS. Study appraisal and synthesis methodsRisk of bias (RoB) was assessed using the Joanna Briggs Institute Checklist for Case-Control and Analytical Cross-Sectional Studies and Cochrane RoB-2.0 tool for randomised trials. A qualitative synthesis was performed summarising main results. ResultsEight databases, 4 trial registries, 9 dissertation repositories, and 1 internet search engine were searched. Fourteen studies including 366 pwMS and 236 healthy controls were included. Most frequently, cognitive impairment was reported as a negative factor influencing MI ability in pwMS. Other negative factors were cognitive fatigue and disability. Inconsistent evidence was found on the contribution of MS phenotype, anxiety, and depression. Using a theory-based MI framework and familiarisation to MI and external cueing may enhance MI ability. LimitationsEligible studies were highly heterogeneous. Conclusion and implications of key findingsCognitive impairment, cognitive fatigue and disability negatively influence MI ability in pwMS. Visual and/or auditory cueing of MI are strategies for facilitating MI ability. Systematic review registration numberPROSPERO CRD42020173081 Contribution of the Paper•Cognitive impairment, disability, and cognitive fatigue negatively affect MI ability in people with multiple sclerosis (pwMS). MS phenotype, anxiety, depression may be further contributing factors.•PwMS with MI ability impairment may not benefit from MI practice as much as pwMS with preserved MI ability.•External visual and/or rhythmic-auditory cueing of MI and the use of a theory-based MI framework facilitates the MI ability and thus, might enhance treatment effects.