Unraveling gait automaticity decline independent of cognitive decline in Parkinson’s disease: a study using the new Parkinson's Affordable Neuro-movement Detection and Analysis (PANDA) system

Background: Daily life mobility often requires walking while performing simultaneous cognitive or motor tasks, such as talking or carrying items This ability relies on automaticity, the nervous system’s capacity to coordinate movements with minimal attentional resources, which is impaired in Parkinson’s disease (PD). Increased attentional control during gait is a key strategy to mitigate this impairment. The interplay between automaticity and cognitive function affects gait performance under dual task (DT) conditions. Aging may also impair both automaticity and cognition. While several studies have examined gait deficiencies under DT in PD, the decline in gait automaticity from early to intermediate stages, independent of cognitive impairment, education, and aging, remains unclear. Objective: To investigate the decline in gait automaticity associated with disease progression, independent of cognition, age, gender, and education in people with PD. Methods: 114 individuals with PD were divided into three groups based on Hoehn and Yahr (H&Y) stages, matched for age, gender, years of schooling, and global cognitive capacity assessed by the Montreal Cognitive Assessment (MoCA). Participants completed three gait tests (Timed Up and Go; 10-meter walking test; 6-meter bidimensional gait analysis - PANDA), under DT conditions two different cognitive tasks (verbal fluency and regressive counting). The order of gait, conditions and cognitive task parameters were randomized. The primary variable for Timed Up and Go and the 10-meter walking test was the time to complete the test. For the 6-meter bidimensional gait analysis (PANDA-gait), the new Gait Performance Index (GPI) was calculated from various gait cinematic parameters. Results: Kruskal-Wallis ANOVA showed that the GPI from DT with verbal fluency differentiated the three groups (H&Y I-II, p<.03; H&Y I-III, p<.00001; H&Y II-II, p<.02). The GPI from DT with regressive counting and the other two clinical tests did not show significant differences between H&Y I-II. Conclusion: Gait automaticity progressively declines from the early stage of PD, as indicated by the GPI, independent of cognitive capacity, age, gender, and education. The GPI, based on the low-cost, brief, and friendly PANDA-gait, may serve as an alternative for early detection and monitoring of gait automaticity decline in PD in clinical settings.