To investigate the differences in gut microbiota in adult patients with irritable bowel syndrome(IBS)and their correlations with quality of life and psychiatric symptoms in patients with different subtypes.

From August 2020 to January 2022, 258 patients with IBS and 50 healthy people were selected as the study objects.According to the type of IBS, they were divided into diarrhea type(IBS-D)group, constipation type(IBS-C)group and mixed type(IBS-M)group.Clinical data were collected, and the differences in gut microbiota, clinical symptom severity evaluation system score(IBS-SSS), SF-36 quality of life scale score, Hamilton Anxiety Scale(HAMA), and Hamilton Depression Scale(HAMD)scores among different groups were compared.The correlations between gut microbiota in each group and IBS-SSS, SF-36 quality of life scale score, HAMA and HAMD scores were analyzed using Spearman method.

The levels of Enterococcus and Enterobacteriaceae in the IBS-D group, IBS-C group and IBS-M group were significantly higher than those in the control group, while the levels of Bifidobacterium and Lactobacillus were significantly lower than those in the control group(P<0.05); The degree of abdominal pain, frequency of abdominal pain, degree of abdominal distension, satisfaction with defecation, degree of interference with daily life, HAMA and HAMD scale scores in the IBS-D, IBS-C and IBS-M groups were significantly higher than those in the control group, while the SF-36 score was significantly lower than that in the control group(P<0.05); The levels of Enterococcus and Enterobacteriaceae in the IBS-D group were positively correlated with the degree of abdominal pain, frequency of abdominal pain, degree of interference with daily life and HAMA score, and negatively correlated with SF-36; The correlations between the levels of Bifidobacteria and Lactobacilli and the above indicators were opposite(P<0.05); In the IBS-C group, the levels of Enterococcus and Enterobacteriaceae were positively correlated with degree of abdominal distention, satisfaction with defecation and degree of interference with daily life, and negatively correlated with SF-36; The correlations between the levels of Bifidobacteria and Lactobacilli and the above indicators were opposite(P<0.05); In IBS-M patients, Enterococcus and Enterobacteriaceae levels were negatively correlated with SF-36, while Bifidobacterium and Lactobacillus were positively correlated with SF-36(P>0.05).

IBS patients, especially diarrhea type and constipation type, have different intestinal flora, and have a certain degree of correlation with the degree of severity of illness, quality of life and mental state.