Concomitant psoriasis may be associated with a more severe disease course in inflammatory bowel disease: a retrospective cohort study.

Psoriasis and inflammatory bowel disease (IBD) share genetic and immunological features, but the impact of concomitant psoriasis on the clinical course of IBD is not well defined. We investigated whether concomitant psoriasis is associated with increased treatment burden and worse outcomes in patients with IBD. This retrospective cohort study included 75 patients with IBD from two academic centers in South Korea (IBD with psoriasis [IBD-PS], n = 25; IBD-only, n = 50). The IBD-PS group included only patients in whom psoriasis was diagnosed prior to IBD. Demographic data and clinical outcomes were analyzed. The primary endpoints were biologic and immunomodulator (IMM) use, and secondary endpoints included IBD-related surgery and emergency room (ER) visits. Time-to-event outcomes were assessed using Kaplan-Meier methods. Biologic and IMM use were significantly higher in the IBD-PS group than in the IBD-only group (biologics: 40% vs. 16%; IMMs: 60% vs. 20%). Treatment escalation to biologics or IMMs occurred earlier in patients with concomitant psoriasis (log-rank P = 0.0021). ER visits were numerically more frequent among patients with severe psoriasis, and the time to first hard clinical event (IBD-related surgery or ER visit) tended to be shorter in the IBD-PS group, although this difference was not statistically significant. Overall, concomitant psoriasis may be associated with increased treatment intensity and a more aggressive IBD course. These findings support the need for coordinated multidisciplinary care and further validation in prospective multicenter studies.