Impaired interhemispheric synchrony in Parkinson's disease with depression.

Yajing Zhu,Jia-Hong Gao,Weiguo Liu,Mingze Xu,Xiao Hu,Xiaopeng Song,Erfeng Li,Yonggui Yuan,Jiajia Liu

doi:10.1038/srep27477

Abstract

The alterations of interhemispheric resting-state functional connectivity (FC) in Parkinson’s disease (PD) with depression remain unclear, so we aimed to explore the differences of interhemispheric FC between PD with and without depression. Twenty-one depressed PD (DPD) patients, 49 non-depressed PD (NDPD) patients and 50 matched healthy controls (HC) participated in this study. Resting-state functional magnetic resonance imaging (fMRI) data were analyzed with the voxel-mirrored homotopic connectivity (VMHC) approach. The DPD patients showed lower VMHC values in the bilateral dorsolateral prefrontal cortex (DLPFC) and calcarine cortex compared to both NDPD and HC groups, and further receiver operating characteristic curves (ROC) analyses revealed that the VMHC in these two brain areas could be used as biomarkers to distinguish DPD from NDPD and from HC. The pooled PD patients (both DPD and NDPD) exhibited decreased VMHC in the bilateral putamen, middle occipital gyrus (MOG), postcentral gyrus (PoCG), paracentral lobule (PCL) and cerebellum posterior lobe when compared with HC. Decreased VMHC values within the DLPFC and calcarine cortex appeared to be unique features for DPD and might be used as potential neuroimaging markers to distinguish DPD patients from NDPD and HC groups. These findings may underlie the neural mechanisms of depression in PD.

Highlights

Variables Age, years Gender, male/female Education, years Disease duration, years HDRS UPDRS-III H & Y MMSE Montreal Cognitive Assessment (MoCA) LED, mg/day
The DPD patients showed significantly reduced voxel-mirrored homotopic connectivity (VMHC) values in the dorsolateral prefrontal cortex (DLPFC)[22,23] and calcarine cortex compared with both NDPD and healthy controls (HC)
The pooled Parkinson’s disease (PD) patients (DPD and NDPD) exhibited lower VMHC in the bilateral putamen, middle occipital gyrus (MOG), postcentral gyrus (PoCG), paracentral lobule (PCL) and cerebellum posterior lobe when compared with the HC group

Summary

Introduction

Variables Age, years Gender, male/female Education, years Disease duration, years HDRS UPDRS-III H & Y MMSE MoCA LED, mg/day. Considering that previous studies have shown decreased interhemispheric FC in major depressive disorder (MDD)[20,21] and depression is the most common psychiatric disorder in PD, it would be meaningful to distinguish the areas affected purely by depression from those affected by motor symptoms. We hypothesized that the depressed and non-depressed PD (DPD and NDPD) patients would exhibit reduced VMHC in different brain regions compared with the healthy controls (HC). Given that depression is associated with abnormal cognitive control from the frontal areas over the subcortical structures, we expected that the prefrontal or limbic regions would be affected in DPD patients besides those motor-related areas affected in both DPD and NDPD

Objectives

Methods

Results

Conclusion