精神分裂症患者脑白质网络拓扑属性的改变

Altered topological properties in white matter structural networks in patients with schizophrenia

目的探讨精神分裂症患者脑白质结构网络拓扑属性的改变及其与临床症状之间的关系。方法对59例精神分裂症患者(患者组)和41名性别、年龄和受教育程度相匹配的健康对照者(对照组)采用确定性纤维追踪技术构建全脑白质结构网络,运用图论分析方法分析精神分裂症患者全脑白质结构网络拓扑属性的特点;采用偏相关分析方法探讨精神分裂症患者全局、节点属性与临床症状之间的关系。结果患者组与对照组全脑白质结构网络均具有小世界属性;与对照组相比,患者组脑白质网络的全局拓扑属性存在异常:最短路径长度显著增加(t=7.95,P=0.0001);全局效率(30.83±16.08,8.25±6.13;t=-9.81,P=0.002)、聚类系数(0.03±0.01,0.02±0.01;t=-4.48,P=0.0003)、平均聚类系数(t=-8.28,P=0.002)、小世界属性(3.92±0.79,2.79±0.56;t=-7.82,P=0.001)显著降低(P<0.005,FDR校正);精神分裂症患者扣带回(t=-4.11,P=0.000),枕上回(t=-6.05,P=0.002),颞上回(t=-10.46,P=0.001),颞中回(t=-10.38,P=0.000),丘脑(t=-6.10,P=0.000)和壳核(t=-8.38,P=0.000)的节点效率显著降低(P<0.005,FDR校正)。偏相关分析结果显示,患者组脑结构网络的全局拓扑属性、节点效率与临床症状之间无明显的相关性(Eglob:r=-0.14,P=0.279;Eloc:r=-0.06,P=0.628;Lp:r=0.28,P=0.031;Cp:r=0.27,P=0.043;λ:r=-0.18,P=0.166;γ:r=-0.29,P=0.026;σ:r=0.26,P=0.048;nEglob:r=0.36,P=0.005;nEloc:r=0.02,P=0.901)。结论精神分裂症患者脑白质结构网络存在全局拓扑属性的异常;皮层-纹状体-丘脑环路脑区的节点效率显著降低。

Objective To explore the changes of whole brain white matter(WM)structural network topological property in patients with schizophrenia(SP)and the associations between WM networks topological efficiency and clinical variables in patients.Methods Deterministic tractography was used to construct the WM networks of 59 patients with SP(patients group)and 41 age-,handedness-,and gender-matched healthy controls(HCs),and graph theoretical methods were applied to investigate abnormalities in the global and nodal properties of the WM network in these patients.Partial correlation analysis was used to analyze the relationship between global and nodal properties of the WM network and clinical variables in patients with SP.Results Both the patients with SP and HCs showed small-world organization of the WM networks.However,compared with HCs,the patients with SP exhibited significant abnormal global topology,including increased shortest path length(t=7.95,P=0.0001)and decreased global efficiency(30.83±16.08,8.25±6.13,t=-9.81,P=0.002),clustering coefficiency(0.03±0.01,0.02±0.01,t=-4.48,P=0.0003),the average clustering coefficiency(t=-8.28,P=0.002),the small-worldness(3.92±0.79,2.79±0.56,t=-7.82,P=0.001)of their WM structural networks(all P<0.005,FDR corrected).Further,the patients with SP showed a reduction in nodal efficiency predominately in the cingulate gyrus(t=-4.11,P=0.000),superior occipital gyrus(t=-6.05,P=0.002),superior temporal gyrus(t=-10.46,P=0.001),middle temporal gyrus(t=-10.38,P=0.000),thalamus(t=-6.10,P=0.000)and putamen(t=-8.38,P=0.000)(P<0.005,FDR corrected).Partial correlation results showed that there was no significant correlation between global topological properties,node efficiency and clinical symptoms in patients group(Eglob:r=-0.14,P=0.279;Eloc:r=-0.06,P=0.628;Lp:r=0.28,P=0.031;Cp:r=0.27,P=0.043;λ:r=-0.18,P=0.166;γ:r=-0.29,P=0.026;σ:r=0.26,P=0.048;nEglob:r=0.36,P=0.005;nEloc:r=0.02,P=0.901).Conclusions The patients with SP exhibit the abnormal of whole brain WM structural network topological property and the node efficiencies of cortico-striato-thalamo circuitry are significantly reduced.