Inflammatory bowel disease and the long-term risk of depression: A prospective cohort study of the UK biobank

Objective: Depression is more common in patients with chronic inflammatory diseases, but whether inflammatory bowel disease (IBD), a chronic, relapsing immune-mediated disease, is associated with a higher risk of depression remains uncertain. Method: We studied 497,134 participants in the UK Biobank, including 3561 IBD patients. Multivariate Cox proportional risk models were constructed to investigate the risk associated with IBD and depression adjusting for potential confounding factors including sociodemographic, lifestyle, and family history variables. Results: The average age of participants was 56.54 +/- 8.09 years; 54.3% were female and 90.4% were white. Over a mean follow-up period of 13.3 years, the cumulative incidence of depression was 8.2% (95% CI: 7.3%-9.1%) in IBD patients compared with 4.9% (95% CI: 4.9%-5.0%) in individuals without IBD. Compared with non-IBD participants, the adjusted hazard ratio (HR) for depression among IBD patients was 1.56 (95% CI: 1.39-1.76), with an adjusted HR of 1.54 (95% CI: 1.25-1.90) in Crohn's disease and 1.52 (95% CI: 1.30-1.78) in ulcerative colitis, respectively. Conclusion: IBD patients had a significantly higher risk of depression than non-IBD participants after adjusting for multiple confounding factors. We recommend screening for depression in middle-aged adults with IBD and no established history of depression.