Association between inflammatory bowel disease and subsequent depression or anxiety disorders- A retrospective cohort study of 31,728 outpatients

Background: Crohn's disease (CD) and ulcerative colitis (UC) are characterized by chronic intestinal and systemic inflammation. The extraintestinal sequelae of inflammatory bowel disease (IBD) are major contributors to disease morbidity and significantly affect patients' quality of life. Here, we evaluated the association between IBD and subsequent depression or anxiety disorder in a large outpatient collective from Germany.Methods: 15,864 individual IBD patients (CD: n = 6,791, UC: n = 9073) and 15,864 nearest neighbor propensity score matched patients without IBD were included from the Disease Analyzer database (IQVIA). Diagnoses of depression and anxiety disorders were compared between IBD and non-IBD patients during a five-year follow-up period using Kaplan-Meier estimators and Cox-regression models.Results: After 5 years of follow-up, depression was diagnosed in 14.4% of CD patients versus 10.2% of matched pairs (p < 0.001) and in 13.1% of UC patients versus 10.1% of matched pairs (p < 0.001). In line, the incidence of anxiety order was significantly higher among CD (4.7% vs. 4.4%, p = 0.009) and UC patients (4.3% vs. 3.5%, p = 0.005). Regression analysis confirmed a significant association between IBD and both mental conditions (Hazard Ratio (HR)(CD/depression): 1.40, HRUC/depression: 1.32, HRCD/anxiety disorder: 1.21, HRUC/anxiety disorder: 1.28). Subgroup analyses revealed a stronger association for CD and depression (HR: 1.51) and UC and depression (HR:1.49) among male patients as well as UC and anxiety disorders (HR: 1.51) among female patients.Conclusion: Our data argue for a significant association between IBD and mental diseases including depression and anxiety disorders. Although further pathophysiological research is warranted, we hypothesize that specific psychological screening measures in IBD patients could improve quality of life and outcome.