AUTHOR=Hobert Markus A. , Nussbaum Susanne , Heger Tanja , Berg Daniela , Maetzler Walter , Heinzel Sebastian 

TITLE=Progressive Gait Deficits in Parkinson’s Disease: A Wearable-Based Biannual 5-Year Prospective Study

JOURNAL=Frontiers in Aging Neuroscience

VOLUME=11

YEAR=2019

URL=https://www.frontiersin.org/journals/aging-neuroscience/articles/10.3389/fnagi.2019.00022

DOI=10.3389/fnagi.2019.00022

ISSN=1663-4365

ABSTRACT=<p><bold>Background:</bold> Gait changes occur during all Parkinson’s disease (PD) stages and wearable sensor-derived gait parameters may quantify PD progression. However, key aspects that may qualify quantitative gait parameters as progression markers in PD remain elusive.</p><p><bold>Objectives:</bold> Longitudinal changes in gait parameters from a lower-back sensor under convenient and challenging walking conditions in early- and mid-stage PD patients (E-PD, M-PD) compared to controls were investigated.</p><p><bold>Methods:</bold> Normal- and fast-pace parameters (step: number, time, velocity, variability) were assessed every 6 months for up to 5 years in 22 E-PD (&lt;4 years baseline disease duration), 18 M-PD (&gt;5 years) and 24 controls. Parameter trajectories and associations with MDS-UPDRS-III were tested using generalized estimating equations.</p><p><bold>Results:</bold> Normal-pace step number (annual change in E-PD: 2.1%, Time<sup>∗</sup>Group: <italic>p</italic> = 0.001) and step time variability (8.5%, <italic>p</italic> &lt; 0.05) longitudinally increased in E-PD compared to controls (0.7%, -12%). For fast pace, no significant progression differences between groups were observed. Longitudinal changes in M-PD did not differ significantly from controls. MDS-UPDRS-III was largely associated with normal-pace parameters in M-PD.</p><p><bold>Conclusion:</bold> Wearables can quantify progressive gait deficits indicated by increasing step number and step time variability in E-PD. In M-PD, and for fast-pace, gait parameters possess limited potential as PD progression markers.</p>