The Relationship between Obsessive-Compulsive Disorder and Irritable Bowel Syndrome: A Systematic Review and Meta-Analysis

Introduction: Irritable bowel syndrome (IBS) might be associated with psychiatric disorders such as obsessive-compulsive disorder (OCD). This meta-analysis was conducted to compare the rate of OCD among patients with IBS and otherwise healthy controls. Methods: This study was conducted using a meta-analysis approach. International databases including PubMed, Web of Science, and Scopus, as well as the Google Scholar search engine were searched from 1985 to August 2020 to find the related studies. The standardized mean difference (SMD) of OCD between case and control groups was calculated and pooled by using a random-effects model. In addition, meta-regression and sub-group analysis were performed to identify variables that possibly explain the heterogeneity. Results: A total of 5167 patients including 1451 IBS patients for case and 3716 for control group entered 15 related studies were included in the analysis. Based on the results of the random effects analysis, the rate of obsessive-compulsive disorder in IBS patients in case group was higher than the control group (Pooled standardized mean difference, 0.76, I2 = 87.8%; 95% CI, 0.54-0.98; P <0.001). Egger’s (P = 0.083) and Begg’s (P = 0.09) tests did not show significant publication bias. Subgroup analysis also revealed that the type of studies and IBS diagnostic criteria were identified as factors affecting heterogeneity. Conclusion: The present meta-analysis demonstrated that the obsessive-compulsive disorder score in IBS patients was higher than the control group, regardless of subgroup analysis or meta-regression. Due to the significant relationship between these two disorders, psychiatrists and gastroenterologists can provide strategies and techniques for individual or group treatment of obsessive-compulsive disorder in patients with IBS based on the cognitive-behavioral therapy.