Differentiating gait behaviors between early-stage dementia with Lewy bodies and Parkinson's disease

Introduction: There is a need for improved biomarkers given that differentiating Dementia with Lewy bodies (DLB) from Parkinson's disease (PD) can be difficult in the earlier stages. Therefore, this study aimed to characterize and evaluate whether gait differences exist between PD and DLB patients in the early course of their disease by assessing normal and dual task walking conditions.

Methods: Twenty-six PD and 20 DLB patients who were within five years of their initial diagnosis and 16 healthy older adults walked across a 6-meter pressure sensor walkway under three conditions (i) self-paced gait, (ii) walking while subtracting 1 s from 100 and (iii) walking while subtracting serial 7 s from 100.

Results: During self-paced gait, DLB patients demonstrated impaired pace (velocity, step length) and rhythm (stance time) compared to early-stage PD patients. Study findings revealed velocity, step length, step time, stance time and step velocity variability offered moderate accuracy for discriminating DLB from PD patients. Increasing cognitive load during dual tasking (serial 1 s vs. serial 7 s) did not expose or intensify any gait differences between PD and DLB.

Conclusion: These findings suggest quantitative gait measurements may be a promising, sensitive, and selective biomarker for differentiating clinical patterns of neurodegeneration. An understanding of early disease gait profiles may also prove useful as a tool for tracking phenoconversion to a synucleinopathy in those prodromal patients who are at high risk, such as those with isolated Rapid Eye Movement Sleep Behavior Disorder.