肠易激综合征伴抑郁患者静息态fMRI度中心度的研究

Degree centrality analysis on resting-state functional MRI in patients with irritable bowel syndrome and depressive symptoms

目的采用静息态功能磁共振成像(rs-fMRI)技术,探讨肠易激综合征伴抑郁症状(DEP-IBS)患者度中心度(DC)的改变。方法选取IBS患者49例,根据汉密尔顿抑郁量表(HAMD)评分后分两组:DEP-IBS组28例,IBS不伴抑郁(nDEP-IBS)组21例。同期招募性别、年龄、受教育年限匹配的健康对照者(HC)36例。入组者均行静息状态下脑部fMRI扫描,经预处理和后处理计算出全脑DC值图,采用单向分类协方差分析(one-way ACNOVA)比较三组间DC值分布图的差异,并分析DEP-IBS组差异脑区的DC值与胃肠道症状评定量表(GSRS)、HAMD-17表评分的相关性。结果One-way ACNOVA结果显示,三组间DC值有差异的脑区为左侧岛叶、左内侧额上回、左侧中央前回;与nDEP-IBS患者和HC相比,DEP-IBS患者DC值显著降低的脑区有左侧岛叶,DC值显著升高的脑区有左侧中央前回。nDEP-IBS组与HC组在该两脑区的DC值没有显著差异;两患者组左内侧额上回的DC值均明显低于HC,而在两组IBS患者间无显著统计学差异。DEP-IBS患者左侧岛叶DC值与HAMD评分呈负相关(r=-0.524,P=0.009)。结论DEP-IBS患者多个脑区DC值存在异常,左侧岛叶、左侧中央前回节点中心地位的异常可能与IBS伴抑郁的病理生理机制有关。

Objective To study the changes of degree centrality(DC)on resting-state MRI in patients with irritable bowel syndrome(IBS)and depressive symptoms.Methods Forty-nine patients with IBS were divided into two groups according to the Hamilton depression scale(HAMD)with(28)and without(21)depressive symptoms.Thirty-six healthy subjects were recruited as control matched in gender,age and education level.All subjects underwent resting-state functional MRI and the DC values of the whole brain were calculated before and after processing.One-way analysis of covariance(ANOVA)was used to compare the DC maps among the three groups.The correlation between the DC values of the different brain regions in the depression group as well as the scores of gastrointestinal symptom rating scale and HAMD was analyzed.Results The brain regions with different DC values among the three groups were left insula,left medial superior frontal gyrus,and left precentral gyrus.The DC value of the left insula was significantly decreased and the DC value of the left central precentral gyrus was significantly increased in IBS with depression.There was no significant difference in DC values between IBS without depression and healthy control.The DC values of the left medial superior frontal gyri in both IBS patient groups were significantly lower than that in healthy control,while there was no significant difference between the two IBS patient groups.The DC value of the left insula was negatively correlated with HAMD score(r=-0.524,P=0.009)in IBS without depression.Conclusion DC values of multiple brain regions were abnormal in patients with IBS and depression.Abnormal changes in node centrality in the left insula and left central precentral gyrus may be related to the pathophysiological mechanism of IBS with depression.