Patterns and factors associated with dose escalation during maintenance treatment for inflammatory bowel disease: a population-based cohort study.

BACKGROUND: Biologics and small-molecule therapies are commonly used for long-term maintenance in patients with inflammatory bowel disease (IBD), including Crohn's disease (CD) and ulcerative colitis (UC). Dose escalation is often required to maintain treatment response, but real-world data on its frequency and contributing factors are limited. OBJECTIVES: To evaluate patterns of dose escalation during maintenance treatment and identify patient- and treatment-related factors associated with dose escalation in IBD. DESIGN: Retrospective, population-based cohort study. METHODS: Using data from the Korean Health Insurance Review and Assessment Service (HIRA), we identified adults with CD or UC who initiated maintenance treatment with biologics or small-molecule agents between 2018 and 2022. Dose escalation was defined as two consecutive doses ⩾50% higher than the expected daily dose within 1 year of treatment initiation. Multivariable logistic regression was used to assess associated factors. RESULTS: Among 2,186 patients with CD and 1,806 with UC, dose escalation occurred in 20.9% and 14.1%, respectively. In CD, ustekinumab had the highest escalation rate (69.1%), compared with infliximab (16.4%), adalimumab (21.2%), and vedolizumab (23.2%). For UC, adalimumab was most frequently escalated (21.8%), followed by tofacitinib (19.5%), ustekinumab (17.9%), and infliximab (10.0%). Steroid use, later lines of therapy (third- and fourth-line) were significantly associated with increased odds of dose escalation. CONCLUSION: Dose escalation is a common occurrence in IBD maintenance therapy, with substantial variation across treatment agents and patient profiles. These findings emphasize the importance of individualized treatment strategies to improve long-term disease control.