Examining Sensory Systems that Contribute to Falls in Parkinson’s disease using Computerized Dynamic Posturography: A Secondary Analysis (Preprint)

BACKGROUND Falls in PD are a complex, multifactorial entity that involves motor, non-motor, environmental, and cognitive factors. While the environmental, cognitive, and motor factors that contribute to falls in PD are well-documented, there are limited investigations into the sensory systems that also contribute to falls. OBJECTIVE The study’s purpose is to determine whether any of the Sensory Organization Test (SOT) conditions or composite scores are associated with falls in people with PD. METHODS The study was a secondary analysis of interventions studies in people with Parkinson's disease aimed at reducing falls and improving mobility. This analysis was to examine correlations between the SOT variables (Conditions 1-6 and composite scores) and the number of falls. Further analysis was performed using the Kruskal–Wallis test to determine if there were differences amongst fall groups and SOT variables). RESULTS Data from 40 participants were included in the study, 24 males and 16 females with a mean age of 68.9 (SD 8.1). Spearman rank correlations found significant negative correlations between the number of falls and SOT Condition (P <.05). Condition 1 (ρ = -.331), Condition 2 (ρ = -.512), and Condition 3 (ρ = -.462). A Kruskal-Wallis test documented a significant group effect between the fall group and Condition 2, (χ2 = 8.434, P = .015) and Condition 3, (χ2= 8.708, P =.013). CONCLUSIONS SOT Condition 2 and 3 were the variables that showed an association with falls in this cohort. The literature indicates that the vestibular system contributes to postural instability; however, it may be that the early decline of the vestibular system, combined with the later decline of the visual system, leads to falls in PD. Readers should exercise caution regarding the results because of the small sample size and the inclusion of only sensory variables. Further investigations should continue on the sensory contributions to falls in PD and in particular. SOT Condition 2. CLINICALTRIAL n/a