肠易激综合征伴抑郁状态患者静息态脑功能局部一致性研究

Regional homogeneity in the patients of irritable bowel syndrome complicated with depression： aresting-state functional magnetic resonance imaging study

目的通过静息态功能磁共振（rs—fMRI）技术对伴抑郁状态肠易激综合征（IBS）患者静息状态下的脑局部一致性（ReHo）变化特征进行研究，探讨IBS脑功能异常与抑郁的关系。方法选取2015年6月至2017年6月杭州师范大学附属医院消化内科诊断的IBS患者35例，根据汉密尔顿抑郁量表（HAMD）评分后分两组：IBS伴抑郁组21例，非抑郁组14例。招募性别、年龄、受教育年限匹配的健康对照者36名。入组者均行3．0Trs．fMRI及3DT1扫描，采用ReHo分析方法比较三组之间局部脑区神经自发活动同步性差异，单因素方差分析观察组间差异，进一步分析ReHo值显著差异脑区与胃肠道症状评定量表（GSRS）、HAMD评分的相关性。结果三组间ReHo有差异的脑区为右侧脑桥、左侧颞下回／梭状回、左侧颞上回／颞极、右侧额下回、右侧枕中回、右侧尾状核、左侧后扣带回／楔前叶、左侧中央后回、右侧顶下小叶；与健康对照组相比，两病例组ReHo均增高的脑区有左侧后扣带回／楔前叶、右侧顶下小叶、左侧中央后回、左侧颞上回／颞极；两病例组ReHo均减低的脑区有右侧枕中回和右侧额下回。IBS伴抑郁组与非抑郁组相比，ReHo增高的脑区为右侧尾状核，其ReHo值在对照组与非抑郁IBS组问差异无统计学意义；ReHo减低的脑区为右侧脑桥、左侧后扣带回／楔前叶、右侧顶下小叶、左侧中央后回。伴抑郁IBS组患者左侧后扣带回ReHo值与HAMD呈显著正相关（r=0．599，P=0．011），左侧中央后回ReHo值与GSRS呈显著正相关（r=0．547，P=0．023）。结论IBS患者存在默认网络和疼痛调节相关脑区的功能失调。IBS伴抑郁患者在痛觉感知及自我调节相关脑区的活动有其特有性，推测IBS对内脏疼痛的自我调节异常，与抑郁的发生有一定的联系，而抑郁又可加剧IBS患者痛觉感知等功能异常。

Objective To explore the changes of the brain regional homogeneity （ReHo） in the patients of irritable bowel syndrome （IBS） complicated with depression by using resting-state functional magnetic resonance imaging （rs-fMRI） and to investigate the relation between abnormal brain function and depression in those patients. Methods A total of 35 patients with IBS were included in this study, collected in Gastroenterology Department of Affiliated Hospital of Hangzhou Normal University from June 2015 to June 2017. According to Hamilton＇s Depression Scale （HAMD）-17 score, the IBS patients was divided into two groups ：IBS with depression group, 21 cases and non-depression group, 14 cases. Thirty-six healthy controls were recruited at the mean time （gender, age and years of education were matched with the patients）. Rs- fMRI and 3D T1 data were acquired with 3.0 T scanners. For all subjects, ReHo, a method measuring the synchronism of regional spontaneous activities, was calculated and one-way ANOVA was performed to assessthe group effects. For those regions with significant group effects, correlation between ReHo values and GSRS and HAMD scores was analyzed too. Results Significant group effects were found in multiple regions：the right pons, the left inferior temporal gyrus （ITG）/fusiform, the left superior temporal gyrus （STG）/ temporal pole, the right inferior frontal gyrus （IFG）, the right middle occipital gyrus （MOG）, the right caudate nucleus, the left posterior cingulate cortex/precuneus （pCC/pC）, the left postcentral gyrus, the rigbt inferior parietal lobule （IPF）. Compared with control group, all the two patient groups had increased ReHo values in the left pCC/pC, the right IPF, the left postcentral gyrus and the left STG/temporal pole; all the two patient groups had decreased ReHo values in the right MOG and the right IFG. Compared with non- depression group, depression group had increased ReHo values in the right caudate nucleus, and decreased ReHo values in the right pons, the left pCC/pC, the right IPF, the left postcentral gyrus. Particularly, there was no significant difference in the ReHo value in the fight caudate nucleus between the control group and the non-depressed IBS group. In the depression group, significantly positive correlations were observed between ReHo values and HAMD scores in the left pCC/pC （ r = 0. 599, P -- 0. O11 ）, and significantly positive correlations were observed between ReHo values and GSRS in the left postcentral gyrus （r = 0. 547, P = O. 023 ）. Conclusions IBS patients have abnormal ReHo regions in default network and pain regulation- associated brain area. IBS with depressed patients has its own characteristics in the brain regions which related with pain perception and self-regulation. IBS could has an abnormal self-regulation of visceral pain, which is associated with the occurrence of depression. Depression can aggravate the disorders of pain perception and other functions of IBS patients.