Preexisting depression and early outcomes in inflammatory bowel disease: a propensity score-matched cohort study.

BACKGROUND: Depression is common in inflammatory bowel disease (IBD) and associated with adverse outcomes, but most studies examine depression arising after IBD diagnosis. Whether depression predating IBD diagnosis is independently associated with early postdiagnosis outcomes remains unclear. METHODS: Using aggregated, de-identified electronic health record data from the TriNetX US Collaborative Network, we conducted parallel propensity score-matched cohort studies in adults with newly diagnosed Crohn's disease (CD) and ulcerative colitis (UC). Exposure was depression recorded 1 to 24 months before the initial IBD diagnosis. Primary outcomes over 24 months were biologic therapy use, emergency department visits, inpatient admissions, and gastrointestinal surgery. Secondary outcomes included colonoscopy, imaging, corticosteroid use, elevated C-reactive protein, anemia, hypoalbuminemia, malnutrition, and all-cause mortality. RESULTS: Preexisting depression was significantly associated with all four primary outcomes in both cohorts. Biologic therapy use showed the strongest association (CD: hazard ratio [HR] 1.20, 95% confidence interval [CI] 1.14-1.28; UC: HR 1.42, 95% CI 1.33-1.52). Emergency department visits (CD: HR 1.11, 95% CI 1.07-1.15; UC: HR 1.20, 95% CI 1.17-1.24), inpatient admission (CD: HR 1.07, 95% CI 1.03-1.11; UC: HR 1.10, 95% CI 1.07-1.14), and surgery (CD: HR 1.14, 95% CI 1.09-1.19; UC: HR 1.10, 95% CI 1.06-1.14) were also elevated. Effect sizes were larger in UC than in CD for most outcomes. C-reactive protein elevation was observed in both cohorts, while anemia and hypoalbuminemia were significantly elevated only in UC. All-cause mortality did not differ significantly. CONCLUSIONS: Preexisting depression is associated with increased treatment escalation and acute care utilization following IBD diagnosis. C-reactive protein elevation in both cohorts may reflect inflammatory burden but could also reflect differential testing. These hypothesis-generating findings suggest that preexisting depression may identify patients warranting closer early monitoring, although further research is needed to determine causality.