首发早发性抑郁症患者脑灰质体积及结构协变网络的异常改变

Abnormal gray matter and structural covariance network in first-episode and early-onset depression

目的探讨首发早发性抑郁症(EOD)患者脑灰质体积(GMV)异常及不同脑区的协同改变。方法对60例首发未用药EOD患者(病例组)与年龄、性别及受教育年限相匹配的64名健康对照者(对照组)行3.0 T 3D T1WI高分辨结构像扫描,采用基于体素形态学的方法得到全脑GMV,采用独立样本t检验比较2组被试GMV是否存在差异,选取差异脑区作为种子点进行结构协变网络(SCN)分析,采用Spearman秩相关分析病例组差异脑区GMV与病程、汉密尔顿抑郁量表(HAMD)17评分的相关性。结果与对照组相比,病例组右侧眶额叶皮质、右侧背外侧前额叶、右侧顶下小叶、右侧顶上小叶、双侧楔前叶GMV升高(P<0.05,FDR校正)。以右侧眶额叶皮质、右侧背外侧前额叶作为种子点进行SCN分析发现病例组存在异常的协变脑区,主要位于额、顶、颞、枕叶皮层及边缘系统、小脑(P<0.05,FDR校正)。此外,病例组右侧眶额叶皮质(r=-0.314,P=0.015)、左侧楔前叶(r=-0.283,P=0.029)GMV与病程呈负相关,右侧背外侧前额叶GMV与HAMD17评分中焦虑/躯体化因子(r=0.331,P=0.010)、左侧楔前叶GMV与HAMD17评分中体质量因子(r=0.255,P=0.049)呈正相关。结论首发未用药EOD患者前额叶、顶叶部分脑区GMV存在异常改变,并且大脑中存在更广泛的协变脑区和结构连接。另外,部分脑区GMV异常改变与临床特征具有相关性。前额叶及顶叶部分脑区或许可成为客观评价抑郁症患者脑结构受损的生物学标记。

Objective To investigate the abnormalities of gray matter volume(GMV)and the synergistic changes in different cerebral regions in the first-episode and early-onset depression(EOD)patients.Methods A total of 60 patients with untreated EOD(EOD group)and 64 healthy controls(control group)matched for age,gender,and education underwent high-resolution T1WI MR scans.Voxel-based morphometry was used to calculate the cerebral GMV.The difference in GMV between the two groups was compared with the t-test.Different brain regions were selected as seeds for structural covariation network(SCN)analysis.Spearman correlation model was used to analyze the correlation between the GMV in different cerebral regions and illness duration as well as the scores of Hamilton rating scale for depression(HAMD)17 items in EOD group.Results Compared to control group,the EOD group had significantly increased GMV in the right orbitofrontal cortex,right dorsolateral prefrontal cortex,right inferior parietal lobule,right superior parietal lobule and bilateral precuneus(P<0.05,corrected by FDR).Based on the right orbitofrontal cortex and dorsolateral prefrontal cortex as seed regions,structural covariance analysis revealed that abnormal cooperative brain regions in EOD group,mainly distributed in the bilateral frontal lobe,parietal lobe,occipital lobe,temporal lobe,paralimbic system and cerebellum(P<0.05,corrected by FDR).In EOD group,significant negative correlations were observed between the GMV in the right orbitofrontal cortex(r=-0.314,P=0.015),the left precuneus(r=-0.283,P=0.029),and illness duration.Significant positive correlations were observed between the GMV in the right dorsolateral prefrontal cortex and the scores of anxiety/somatization factor of HAMD17(r=0.331,P=0.010),the left precuneus and weight factor of HAMD17(r=0.255,P=0.049),respectively.Conclusions Abnormal GMV changes are observed in some regions of the prefrontal and parietal lobule in patients with untreated EOD,accompanied by extensive covariant brain regions and additional structural connectivity.In addition,the abnormal GMV changes in some regions are associated with clinical features.Part of the prefrontal and parietal lobule may be the biomarkers to objectively evaluate abnormal brain structure in depression patients in the early stage.