Mediation analysis for integrating motor symptoms of Parkinson's disease, cognitive function, and gait...

In Parkinson's disease (PD) patients, the severity of motor symptoms is closely related to the degree of gait disorder and cognitive impairment; notably, the latter also exhibits a significant correlation with gait disorder. Evidently, there exists a complex relationship between motor symptoms, cognitive function, and gait characteristics.

This study aims to conduct an in-depth analysis of the relationships among MDS-UPDRS III score, MoCA score, and gait parameters by constructing a mediation model.

We found that a higher MDS-UPDRS III score was associated with a smaller plantar dorsiflexion angle, slower velocity, and worse swing phase symmetry, and these associations were not mediated by the MoCA score. Age was a confounder in the relationship between MDS-UPDRS III score, MoCA, and velocity. A higher MDS-UPDRS III score was associated with shorter stride length, and this association was partially mediated by the MoCA score.

The results indicated that, when analyzing plantar dorsiflexion angle and swing phase symmetry in PD patients, the influence of motor symptoms was dominant; when analyzing stride length, motor symptoms and cognitive function need to be considered simultaneously; when analyzing velocity, the influence of motor symptoms and age should be focused on.