Effectiveness of Motor Imagery in the Rehabilitation of People With Parkinson's Disease: A Systematic Review and Meta-Analysis

Background and Objective With more research completed using Motor imagery (MI) in people with Parkinson's disease, this study gathered and synthesized evidence on the use of MI for Parkinson's disease in improving rehabilitation outcomes.Methods Medical Literature Analysis and Retrieval System Online, Embase, Web of Science, The Cochrane Library, PsycINFO, Cumulative Index to Nursing and Allied Health Literature, and Scopus were searched from inception to May 2023. We included randomized controlled trials that examine the effects of MI on individuals with Parkinson's disease. Two reviewers selected articles and extracted study characteristics and results independently. The Physiotherapy Evidence Database scale was used to assess the methodological quality. Mean differences and 95% confidence intervals were calculated. Heterogeneity was assessed using the I2 statistic.Results Thirteen articles with 12 studies were included, involving 320 individuals with Parkinson's disease, with moderate to high methodological quality (mean = 6.62/10). Compared with the control group, 3 articles reported significant greater improvements in cognitive function, 7 reported significant greater improvement in motor function, 1 article reported significant greater improvement in quality of life, and 1 reported significant greater confidence in daily task performance. No statistically significant effects were found in the meta-analyses. Conclusion. Results of individual articles were in favor of the MI intervention. No statistically significant results were found in the meta-analyses. This might be due to the small number of studies and the heterogeneity of interventions and outcome measures used. MI may be effective in improving some rehabilitation outcomes, but meta-analytic evidence is lacking. More research with larger sample size and less heterogeneous samples, interventions, and outcome measures, is warranted.Systematic Review Registration PROSPERO registration number CRD42021230556.