自杀未遂青少年抑郁症患者脑网络分析

目的 观察自杀未遂青少年抑郁症患者脑网络图论和功能连接（FC）改变。方法 对自杀未遂青少年抑郁症组33例（未遂组）、不伴自杀行为青少年抑郁症组（单纯抑郁组）40例及52名健康青少年（NC组）行采集fMRI数据，获取并分析比较图论整体及局部属性指标，以发生改变脑区作为种子点，构建基于全脑体素的FC，分析比较组间FC差异。结果 脑网络均存在小世界属性。相比NC组，抑郁症患者视觉网络度中心性降低（P<0.01），且与汉密尔顿抑郁量表评分呈负相关（r=-0.31，P<0.01）；其躯体运动网络、突显网络FC下降，未遂组注意网络FC较单纯抑郁组增强（均通过TFCE校正，P<0.05）。结论 青少年抑郁症患者视觉网络信息传递能力下降，其程度与抑郁严重程度相关；注意网络病变所致注意空间能力受损可能是青少年抑郁症患者自杀行为的病理机制。

Brain network analysis of adolescent depression with attempted suicide

Objective To explore the changes of the graph theory metrics and the functional connectivity (FC) of adolescent depression with attempted suicide. Methods Resting-state functional MRI (rs-fMRI) data of 33 patients of adolescent depression with attempted suicide (attempted suicide group), 40 patients of adolescent depression without attempted suicide (no suicide group) and 52 normal adolescents (NC group) were collected, and a binary network was constructed. The brain regions changed in the graph theory attribute were selected as the seeds, and FC between seed and all the other voxels within the whole brain was computed and compared among groups. Results There were small world attributes in all subjects. Compared with NC group, the degree of centrality significantly decreased in adolescent depression patients (P<0.01), and there were negative correlations between the decreased degree of centrality and Hamilton Depression Scale scores (r=-0.31, P<0.01). Compared with NC group, FC of the somatomotor networks and the salience network decreased in adolescent depression patients, while FC of the attention network in attempted suicide group increased than in no suicide group (all TFCE correction, P<0.05). Conclusion Decrease of visual network information transmission ability in patients of adolescent depression is related to the severity of depression. The abnormal attention space ability caused by the attention network lesions may be the pathological mechanism of suicidal attempt in patients of adolescent depression.