The Influence of Antidepressants on the Disease Course Among Patients With Crohn's Disease and Ulcerative Colitis-A Danish Nationwide Register-Based Cohort Study.

Background: Psychiatric comorbidity might modify the disease course adversely in patients with inflammatory bowel disease (IBD). Treatment options include antidepressants, which, apart from improving mood, have anti-inflammatory properties that might modify the disease course. This nationwide study aimed to examine the influence of antidepressants on the disease course among patients with ulcerative colitis (UC) and Crohn's disease (CD).

Methods: Patients registered with an incident diagnosis of CD or UC in the Danish National Patient Register (2000-2017) were included. Information on antidepressant use and proxy measures of disease activity (health care and drug utilization) was extracted from national population registers. Poisson regression was performed to estimate disease activity rates by antidepressant use adjusted for confounders. Furthermore, the analyses were performed stratified by IBD subtype and type of antidepressants.

Results: A total of 42,890 patients were included (UC: 69.5%; CD: 30.5%). When adjusted for confounders, a lower incidence rate of disease activity was found among antidepressant users compared with nonusers in both CD (incidence rate ratio [IRR], 0.75; 95% confidence interval [CI], 0.68-0.82) and UC (IRR, 0.90; 95% CI, 0.84-0.95) patients. Further, markedly lower rates of disease activity were found among CD (IRR, 0.51; 95% CI, 0.43-0.62) and UC (IRR, 0.67; 95% CI, 0.59-0.75) patients with no use of antidepressants before IBD onset.

Conclusions: In this nationwide study, antidepressant use was found to be beneficial on the disease course among patients with UC and CD, particularly in patients with no use of antidepressants before IBD onset. Randomized controlled trials are warranted to investigate the potential of antidepressants being an adjunct treatment to conventional IBD therapy.