Involvement of cortical dysfunction in frequent falls in patients with Parkinson's disease

Introduction: Gait and balance disorders are common clinical features of Parkinson's disease (PD). Although falls significantly affect the activities of daily living (ADL) and quality of life (QOL) of patients with PD, the underlying neural mechanisms associated with frequent falls in PD patients are still unclear. Methods: Hypothesizing that the cerebral cortex would contribute to frequent falls in PD, we obtained 3D T1-weighted images from 91 non-dementia patients with PD and performed voxel-based morphometric analysis (VBM). Gray matter volume was compared between patients with and without frequent falls to investigate the structural basis for frequent falls in PD. As an ancillary analysis, we also performed resting-state functional magnetic resonance analysis using data from 58 patients. Results: Among the 91 patients, 36 had experienced frequent falls. Gray matter volume in the right superior temporal gyrus (STG) and the right inferior parietal lobule (IPL) of these patients was significantly lower than that of the non-frequent fallers. There was also a significant correlation between fall frequency and gray matter volume in these two regions. Additionally, resting-state functional analysis revealed lower connectivity in the right posterior perisylvian region, including in the IPL and STG, in frequent fallers than in non-frequent fallers. Conclusion: Frequent falls in PD are associated with structural and functional abnormality of the cerebral cortex including the right IPL and STG.