To investigate the clinical symptoms and mental state of patients with irritable bowel syndrome with diarrhea (IBS-D), and to analyze the characteristics of psychological disorders in patients with IBS-D and their impacts on intestinal symptoms.

From July 2009 to June 2012, patients met Rome Ⅲ criteria of IBS-D were consecutively enrolled at Peking Union Medical College Hospital. The symptoms of IBS were investigated by IBS symptoms questionnaire and mental state were evaluated by Hamilton anxiety scale (HAMA) and Hamilton depression scale (HAMD). The differences in intestinal symptoms between patients with comorbid psychological disorders and without psychological disorders were compared. And the correlation between the scores of HAMA, HAMD and intestinal symptoms were analyzed. Two independent sample t-tests, chi square test and Fisher exact probability were performed for statistical analysis. Spearman rank correlation was used for correlation analysis.

A total of 231 patients with IBS-D were enrolled. There were 133 males and 98 females with an age of (42.8±11.1) years old and a disease course of (4.5 years (8.0 years)). The HAMA and HAMD scores were 17.00±7.12 and 14.05±6.00, respectively, and 72.29% (167/231) patients had comorbid psychological disorders, 32.90% (76/231) patients had moderate to severe anxiety and/or depression, mainly had anxiety. The proportion of patients with ordinary abdominal pain or discomfort and the proportion of moderate to severe abdominal pain or discomfort in patients with psychological disorders were higher than those of patients without psychological disorders (53.29%, 89/167 vs. 34.37%, 22/64; 49.44%, 44/89 vs. 18.18%, 4/22), and the differences were statistically significant (χ²=6.634 and 7.002, P=0.010 and 0.009). In patients with comorbid psychological disorders, more patients had frequent onset of abdominal pain or discomfort, less achieved completely improvement after defecation, and often accompanied with defecation related symptoms. The HAMD score was positively correlated with the onset frequency of IBS (r=0.172, P=0.009), and the HAMA score was positively correlated with the degree of abdominal pain or discomfort before defecation (r=0.134, P=0.042). The HAMA and HAMD scores were negatively correlated with the improvement degree of abdominal pain or discomfort after defecation (r=-0.215, P=0.001; r=-0.251, P<0.01), and were positively correlated with waiting time for symptoms improvement (r=0.175, P=0.008; r=0.219, P= 0.001).

Most IBS-D patients have comorbid psychological disorders, anxiety and/or depression greatly impact the intestinal symptoms of patients with IBS.

Irritable bowel syndrome; Depression; Anxiety; Psychological disorders; Intestinal symptoms