首发抑郁症患者肠道菌群特征及其与健康人群肠道菌群结构的差异

比较首发抑郁症患者与健康人群肠道菌群的差异，探讨抑郁症患者肠道菌群和抑郁症状间的关系，为抑郁症的发病机制研究及治疗提供一定的理论依据。

选择2019年10月至2020年9月我院收治的首发抑郁症患者及健康人群为研究对象，分为抑郁组（n = 23）和健康组（n = 31）。对研究对象肠道菌群16S rRNA基因中V4−V5区域片段进行基因测序，使用汉密尔顿抑郁量表对两组对象抑郁症状进行评估。检测两组对象肠道菌群α多样性、β多样性和组间差异。

首发抑郁症患者与健康人群肠道菌群多样性差异无统计学意义（均P＞0.05）。两组对象肠道拟杆菌门和拟杆菌纲的相对丰度差异有统计学意义（均P＜0.05）。两组对象芽胞杆菌目等的相对丰度差异有统计学意义（P＜0.05）。在属水平和种水平上，两组对象分别有28个菌属和40个菌种的丰度差异有统计学意义（均P＜0.05）。LEfSe分析显示，拟杆菌科、艾克曼菌科等10种菌科是造成两组对象肠道菌群差异的主要细菌。

首发抑郁症患者与健康人群肠道菌群多样性未发现显著差异，但抑郁症患者肠道菌群结构与健康人群相比发生了改变，主要体现在拟杆菌属等细菌在抑郁症患者肠道中的相对丰度显著上升。

The difference in intestinal flora between first-episode depression patients and healthy individuals

Objective To compare the difference in the intestinal flora between first-episode depression (FED) patients and normal individuals, explore the relationship between intestinal flora and depression symptoms, and provide certain theoretical basis for the pathogenesis of depression and treatment. Methods FED patients and healthy individuals in our hospital from Oct 2019 to Sep 2020 were enrolled. The V4 - V5 region fragments in the 16S rRNA gene in intestinal flora of the depression group (n = 23) and the health group (n = 31) were genetically sequenced, and the Hamilton depression scale was used to evaluate the depression symptoms in the two groups. The relative abundance of intestinal flora was tested, and α diversity test, β diversity test, and the significance test between groups were performed. Results There was no significant difference in the diversity of intestinal flora between the two groups (all P＞0.05). The relative abundances of Bacteroidetes and Bacteroidetes in the two groups were significantly different (all P＜0.05), and at the order level, Bacillales was significantly different in the two groups (P＜0.05). At the genus level and species level, the abundances of 28 genera and 40 species of bacteria were significantly different between the two groups (all P＜0.05). According to LEfSe analysis, ten bacterial colonies including Bacteroidaceae and Akkermansiaceae were the main bacterial colonies that caused the difference in intestinal flora between the depression group and the control group. Conclusion In this study, no significant difference was found in the diversity of intestinal flora between patients with FED and normal individuals. The structural composition of intestinal flora of patients with FED has changed compared with that of normal people, which is mainly reflected in the significant increase in the relative abundance of Bacteroides in the intestines of depression patients.