dc.description.abstract | Background: Parkinson’s disease (PD) is a highly heterogeneous condition and various clinical subtypes have been discriminated. The objective of this study was to investigate differences in subcortical-cortical structural covariance (SC) between two PD subtypes. These subtypes differed on motor symptom severity, executive functioning and verbal memory impairments.
Methods: A seed-based SC analysis was conducted on magnetic resonance imaging (MRI) scans from 57 PD patients who were screened at the VU University medical center. We examined SC of the dorsal caudal putamen (DCP), the dorsal caudate nucleus (DCN) and the anterior hippocampus (AH), which are considered key areas within brain networks important for motor-, executive- and memory function in PD respectively. Post hoc, mediation analyses were performed to investigate whether the clinical measures would mediate SC.
Results: No significant results were found using FWE-correction. However, several uncorrected SC differences were found between C3 and C4 using exploratory analyses. Adding the relevant clinical measures as a mediator did not explain the SC. Discussion: The current study adds to a growing body of literature of heterogeneity in PD pathology. Future research on the underlying pathology of PD subtypes is required within larger patient groups, with special attention to gender differences. Graph theory based SC analysis or morphometric similarity mapping could be promising alternative approaches to investigate this topic. | |