RESUMO
OBJECTIVE: The goal of this study was to analyze how depression associated with Parkinson's disease (PD) affected gait variability in these patients using a dual-task paradigm. Additionally, the dependency of the executive functions and the impact of depression on gait variability were analyzed. PATIENTS AND METHODS: Three subject groups were included: patients with PD, but no depression (PD-NonDep; 14 patients), patients with both PD and depression (PD-Dep; 16 patients) and healthy controls (HC; 15 subjects). Gait was recorded using the wireless sensors. The participants walked under four conditions: single-task, motor dual- task, cognitive dual-task, and combined dual-task. Variability of stride length, stride duration, and swing time was calculated and analyzed using the statistical methods. RESULTS: Variability of stride duration and stride length were not significantly different between PD-Dep and PD-NonDep patients. The linear mixed model showed that swing time variability was statistically significantly higher in PD-Dep patients compared to controls (pâ¯=â¯0.001). Hamilton Disease Rating Scale scores were significantly correlated with the swing time variability (pâ¯=â¯0.01). Variability of all three parameters of gait was significantly higher while performing combined or cognitive task and this effect was more pronounced in PD-Dep group of patients. CONCLUSIONS: Depression in PD was associated with swing time variability, and this effect was more prominent while performing a dual-task. SIGNIFICANCE: Diagnosing and treating depression might be important for gait improvement and fall reduction in PD patients.