Lee Silverman Voice Treatment (LSVT)-BIG to improve motor function in people with Parkinson's disease: a systematic review and meta-analysis

Objective: The technique called Lee Silverman Voice Treatment (LSVT)-LOUD has previously been used to improve voice quality in people with Parkinson's disease. The objective of this study was to assess the effectiveness of an alternate intervention, LSVT-BIG (signifying big movements), to improve functional mobility. Design: Systematic review with meta-analysis of randomized trials. Data sources: Medline, Embase, CINAHL, AgeLine, Scopus and Cochrane Library were searched from inception to September 2017 using multiple search terms related to Parkinson's disease and LSVT-BIG. Review method: Two researchers searched the literature for studies of the LSVT-BIG intervention of 16 sessions, delivered by a certified instructor over four weeks, to any other intervention. Outcomes related to functional ability were included. Study quality was appraised using the Cochrane Risk of Bias tool. Results: Four studies were included, reporting on three randomized trials of 84 participants with mild Parkinson's disease. Compared to physiotherapy exercises, or a shorter training protocol, there was a significant improvement in motor function assessed with the Unified Parkinson's Disease Rating Scale part III (mean difference = -3.20, 95% confidence interval = -5.18 to -1.23) and a trend towards faster Timed Up and Go performance (mean difference = -0.47, 95% confidence interval = -0.99 to 0.06) and 10-metre walk test (mean difference = -0.53, 95% confidence interval = -1.07 to 0.01). Conclusion: Compared to shorter format LSVT-BIG or general exercise, LSVT-BIG was more effective at improving motor function. This provides preliminary, moderate quality evidence that amplitude-oriented training is effective in reducing motor impairments for people with mild Parkinson's disease.