Can virtual reality interventions reduce falls in Parkinson's disease? A systematic review and meta-analysis of randomized trials.

BACKGROUND: Virtual reality (VR) is increasingly utilized in neurorehabilitation, yet the translational gap between improved clinical scores and actual fall reduction in Parkinson’s disease (PD) persists. OBJECTIVE: We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) in individuals with PD to quantify the effect of VR interventions on fall rate relative to conventional controls. METHODS: A systematic search of six major databases was conducted. Methodological quality was assessed using RoB 2 and certainty of evidence via GRADE. The primary outcome was fall rate, analyzed as incidence rate ratio (IRR), while secondary outcomes included the number of fallers, Activities-Specific Balance Confidence (ABC) scale, and Falls Efficacy Scale (FES). Subgroup analyses, based on activity of controls and supervision were planned and performed. RESULTS: We included 19 RCTs (22 reports). A meta-analysis on four trials (n = 270) assessing the primary outcome showed a pooled IRR of 0.54 (95% confidence interval [CI] 0.35–0.84), indicating a 46% reduction in fall rate favoring VR (low-certainty evidence). Four trials (n = 335) also showed a 25% relative reduction in the number of fallers with at least one fall (low-certainty evidence; risk ratio [RR] 0.75, 95% CI 0.60–0.93). Psychological benefits were also suggested, while further subgroup analyses revealed that improvements were driven by supervised interventions, showing a statistically significant effect on FES family at post-intervention (standardized mean difference [SMD] -0.62; 95% CI -0.93, -0.31) and ABC at follow-up (mean difference [MD] 5.47; 95% CI 2.42, 8.53). CONCLUSIONS: VR-based rehabilitation may meaningfully reduce fall rate and the proportion of fallers in people with PD compared to conventional controls, although current evidence is of low certainty and is based on a small number of trials. Further research is needed in assessing fall rate with priority and in comparing equal VR protocols, particularly with different supervision levels, to determine optimal implementation.