首发抑郁症的患者静息态脑网络度中心度与认知功能研究

Study on the degree centrality of resting state brain network and cognitive function in patients with first episode depression

目的基于体素的度中心度方法(DC)分析探讨首发抑郁症患者静息态脑网络节点中心地位的特点及其认知功能损害的神经影像学机制。方法纳入2013年5月至2019年3月武汉大学人民医院收治的首发抑郁症患者及同期招募健康对照各30例进行静息态磁共振扫描,并行数字符号测试、数字广度测试及语言流畅性测试。对静息态磁共振数据进行常规预处理,计算各组DC值图,采用双样本t检验分别比较两组DC值及认知功能测试评分,最后采用Pearson相关分析静息态脑网络DC值与认知功能测试评分的相关性。结果(1)与健康对照组比较,首发抑郁症患者在数字符号测试[(62.37±10.30)分比(70.47±10.12)分]、数字广度测试[顺背、倒背:(8.20±0.76)分比(9.27±1.12)分、(5.30±1.15)分比(5.73±1.56)分]及语言流畅性测试评分[(19.50±2.57)分比(22.57±4.45)分]明显下降,差异均有统计学意义(均P<0.01)。(2)与健康对照组比较,首发抑郁症患者左侧额上回DC值下降,右侧枕叶距状皮质、右侧扣带回中部、右侧纹状体DC值升高(P<0.01,AlphaSim校正,体素个数>55)。(3)相关分析结果显示,首发抑郁症患者右侧纹状体DC值与数字符号测试评分呈负相关(r=-0.48,P=0.01);左侧额上回DC值与数字广度测试及语义流畅性测试评分呈正相关(r=0.38,P=0.04;r=0.41,P=0.03)。结论首发抑郁症患者存在静息状态脑网络节点中心地位的改变,这些脑区主要位于右侧枕叶距状皮质、右侧扣带回中部、右侧纹状体及左侧额上回,其中右侧纹状体及左侧额上回脑网络节点中心地位的改变与患者认知功能损害密切相关,将为探索抑郁症认知功能损害的神经影像机制提供可能的神经影像依据。

Objective Based on the voxel-based degree centrality (DC) analysis, to investigate thecharacteristics of resting state brain network node centrality and the neuroimaging mechanism of cognitiveimpairment in patients with first-episode depression. Methods From May 2013 to March 2019, totally 30patients with first-episode depression in Renming Hospital of Wuhan University (MD group) and 30 healthycontrols (NC group) were included in the study. All subjects underwent resting-state fMRI. Then Digital SymbolTest (DST), Digital Span Test (DSPT), and Verbal Fluency Test (VFT) were performed. The resting state fMRIdata were routinely preprocessed, and the DC map of each group was calculated. The DC value and cognitivefunction test score of the two groups were compared by double sample t-test. Pearson correlation was usedto analyze the correlation between the DC value and cognitive function test scores. Results (1)Comparedwith NC gorup, MD group showed decreased score in DST [(62.37±10.30) vs (70.47±10.12)], DSPT[forward: (8.20±0.76) vs (9.27±1.12);backward (5.30±1.15) vs (5.73±1.56)], and VFT [(19.50±2.57) vs(22.57±4.45)], and the differences were statistically significant (P< 0.01). (2) Compared with NC group, theDC value of the left superior frontal gyrus decreased, while the DC value of the right occipital calarine cortex,right middle cingulate cortex, right striatum increased in patients with first-episode depression (P<0.01, AlphaSimcorrection, voxel number > 55). (3) The Pearson correlation analysis showed that the DC value of the rightstriatum was negatively correlated with DST score of patients with first-episode depression (r=-0.48,P=0.01), while the DC value of the left superior frontal gyrus was positively correlated with the DSPT score and VFT score(r=0.38, P=0.04;r=0.41, P=0.03). Conclusions There are changes in centrality of brain network nodes inpatients with first episode of depression. These brain regions are mainly located in the right occipital cortex,the middle of right cingulate gyrus, the right striatum and the left superior frontal gyrus. The changes of thecentral position of the network nodes in the right striatum and the left superior frontal gyrus are closely relatedto the cognitive impairment of patients, which will provide a possible neuroimaging basis for exploring theneuroimaging mechanism of cognitive impairment in depression.