The Relative Contribution of Physical and Cognitive Fall Risk Factors in People With Parkinson's Disease: A Large Prospective Cohort Study

Background. In order to develop multifaceted fall prevention strategies for people with Parkinson's disease (PD), greater understanding of the impact of physical and cognitive performance on falls is required. Objective. We aimed to identify the relative contribution of a comprehensive range of physical and cognitive risk factors to prospectively-measured falls in a large sample of people with PD and develop an explanatory multivariate fall risk model in this group. Methods. Measures of PD signs and symptoms, freezing of gait, balance, mobility, proprioception, leg muscle strength, and cognition were collected on 205 community-dwelling people with PD. Falls were monitored prospectively for 6 months using falls diaries. Results. A total of 120 participants (59%) fell during follow-up. Freezing of gait (P < .001), dyskinesia (P = .02), impaired anticipatory and reactive balance (P < .001), impaired cognition (P = .002), reduced leg muscle strength (P = .006), and reduced proprioception (P = .04) were significantly associated with future falls in univariate analyses. Freezing of gait (risk ratio [RR] = 1.03, 95% confidence interval [CI] = 1.00-1.05, P = .02), impaired anticipatory (RR = 1.01, 95% CI = 1.00-1.02, P =.03) and reactive (RR = 1.26, 95% CI = 1.01-1.58, P = .04) balance, and impaired orientation (RR = 1.28, 95% CI = 1.01-1.62, P = .04) maintained significant associations with falls in multivariate analysis. Conclusion. The study findings elucidate important physical and cognitive determinants of falls in people with PD and may assist in developing efficacious fall prevention strategies for this high-risk group.