重型抑郁障碍患者默认网络静态与动态功能连接变化

目的 基于静息态功能MRI(rs-fMRI)观察重型抑郁障碍(MDD)患者默认网络(DMN)静态与动态功能连接变化。方法 回顾性分析55例MDD患者(MDD组)及35名健康体检者(对照组)头颅高分辨率结构图像及rs-fMRI;以Matlab平台CONN工具箱进行图像预处理及独立成分分析(ICA)以提取DMN;比较组间DMN与全脑静态与动态功能连接变化;采用Pearson相关性分析观察MDD组与对照组存在差异脑区DMN与汉密尔顿抑郁量表-24项(HAMD-24)、汉密尔顿焦虑量表(HAMA)及韦氏智力测验评分的相关性。结果 相比对照组,MDD组DMN与丘脑、楔前叶及中央前回静态功能连接均减弱(P均＜0.05);MDD组DMN与丘脑功能连接强度与HAMD-24评分呈低度负相关(r=－0.333,P=0.014)。相比对照组,MDD组DMN内侧前额叶皮层、左/右外侧顶叶与伏隔核,以及左外侧顶叶、后扣带回与丘脑动态功能连接均减弱。MDD组DMN内侧前额叶皮层-伏隔核、后扣带回-丘脑动态功能连接强度与HAMD-24评分呈低度正相关(r=0.313,P=0.019;r=0.311,P=0.021)。结论 MDD患者DMN与局部脑区存在静态与动态连接异常,部分与抑郁症严重程度相关。

Changes of static and dynamic functional connectivity of default mode network in patients with major depressive disorder

Objective To explore changes of static and dynamic functional connectivity of default mode network (DMN) in patients with major depressive disorder (MDD) based on resting-state functional MRI (rs-fMRI). Methods Brain high-resolution structural MRI and rs-fMRI data of 55 MDD patients (MDD group) and 35 healthy subjects (control group) were retrospectively analyzed. Pre-processing and group independent component analysis (ICA) were performed to extract DMN using CONN toolbox running on the Matlab. Static and dynamic changes of functional connectivity of DMN and whole brain were compared between groups. Pearson correlation analysis was used to explore correlations of DMN in MDD group being different functional connectivity compared with control group and scores of Hamilton depression scale-24 (HAMD-24), Hamilton anxiety scale (HAMA) and Wechsler intelligence test. Results Compared with control group, static functional connectivity of DMN over thalamus, precuneus and precentral gyrus in MDD group were weakened (all P＜0.05), while functional connectivity strength between DMN and thalamus was lowly negatively correlated with HAMD-24 scores (r=－0.333, P=0.014). Compared with control group, dynamic functional connectivity between both medial prefrontal cortex and left/right lateral parietal lobe of DMN and nucleus accumbens, as well as left lateral parietal lobe, posterior cingulate gyrus of DMN and thalamus in MDD group were all weakened. In MDD group, dynamic functional connectivity strength of medial prefrontal cortex-nucleus accumbens and posterior cingulate gyrus-thalamus of DMN were both lowly positively correlated with HAMD-24 scores (r=0.313, P=0.019; r=0.311, P=0.021). Conclusion MDD patients had abnormal static and dynamic functional connectivity of DMN and other brain regions, some were associated with the severity of depressive disorder.