Chen Shuai, Wang Sheng-Hui, Bai Ying-Ying, Zhang Jie-Wen, Zhang Hong-Ju
Department of Neurology, Zhengzhou University People's Hospital, Henan Provincial People's Hospital, Zhengzhou, China.
Front Aging Neurosci. 2022 Apr 11;14:820479. doi: 10.3389/fnagi.2022.820479. eCollection 2022.
Idiopathic rapid eye movement Sleep Behavior Disorder (iRBD) is considered as a prodromal and most valuable warning symptom for Parkinson's disease (PD). Although iRBD and PD without RBD (nRBD-PD) are both α-synucleinopathies, whether they share the same neurodegeneration process is not clear enough. In this study, the pattern and extent of neurodegeneration were investigated and compared between early-stage nRBD-PD and iRBD from the perspective of whole-brain functional network changes.
Twenty-one patients with iRBD, 23 patients with early-stage nRBD-PD, and 22 matched healthy controls (HCs) were enrolled. Functional networks were constructed using resting-state functional MRI (fMRI) data. Network topological properties were analyzed and compared among groups by graph theory approaches. Correlation analyses were performed between network topological properties and cognition in the iRBD and nRBD-PD groups.
Both patients with iRBD and patients with early-stage nRBD-PD had attention, executive function, and some memory deficits. On global topological organization, iRBD and nRBD-PD groups still presented small-worldness, but both groups exhibited decreased global/local efficiency and increased characteristic path length. On regional topological organization, compared with HC, nRBD-PD presented decreased nodal efficiency, decreased degree centrality, and increased nodal shortest path length, while iRBD presented decreased nodal efficiency and nodal shortest path. For iRBD, brain regions with decreased nodal efficiency were included in the corresponding regions of nRBD-PD. Nodal shortest path changes were significantly different in terms of brain regions and directions between nRBD-PD and iRBD. Attention deficits were correlated with local topological properties of the occipital lobe in both iRBD and nRBD-PD groups.
Both global and local efficiency of functional networks declined in nRBD-PD and iRBD groups. The overlaps and differences in local topological properties between nRBD-PD and iRBD indicate that iRBD not only shares functional changes of PD but also presents distinct features.
特发性快速眼动睡眠行为障碍（iRBD）被认为是帕金森病（PD）的前驱症状且是最有价值的警示症状。尽管iRBD和无RBD的PD（nRBD-PD）均为α-突触核蛋白病，但它们是否共享相同的神经退行性变过程尚不清楚。在本研究中，从全脑功能网络变化的角度研究并比较了早期nRBD-PD和iRBD之间神经退行性变的模式和程度。
纳入21例iRBD患者、23例早期nRBD-PD患者和22例匹配的健康对照（HC）。使用静息态功能磁共振成像（fMRI）数据构建功能网络。采用图论方法分析并比较各组的网络拓扑特性。对iRBD组和nRBD-PD组的网络拓扑特性与认知进行相关性分析。
iRBD患者和早期nRBD-PD患者均存在注意力、执行功能及一些记忆缺陷。在全局拓扑组织方面，iRBD组和nRBD-PD组仍呈现小世界特性，但两组均表现出全局/局部效率降低和特征路径长度增加。在区域拓扑组织方面，与HC相比，nRBD-PD表现为节点效率降低、度中心性降低和节点最短路径长度增加，而iRBD表现为节点效率和节点最短路径降低。对于iRBD，节点效率降低的脑区包含在nRBD-PD的相应区域中。nRBD-PD和iRBD在脑区和方向上的节点最短路径变化存在显著差异。iRBD组和nRBD-PD组的注意力缺陷均与枕叶的局部拓扑特性相关。
nRBD-PD组和iRBD组的功能网络全局和局部效率均下降。nRBD-PD和iRBD在局部拓扑特性上的重叠和差异表明，iRBD不仅与PD共享功能变化，还呈现出独特特征。
