Predictors of Complicated Disease Course in Children and Adults With Ulcerative Colitis: A Nationwide Study From the epi-IIRN

Abstract

Abstract Background Data on predictors of complicated ulcerative colitis (UC) course from unselected populations cohorts are scarce. We aimed to utilize a nationwide cohort to explore predictors at diagnosis of disease course in children and adults with UC. Methods Data of patients diagnosed with UC since 2005 were retrieved from the nationwide epi-IIRN cohort. Complicated disease course was defined as colectomy, steroid-dependency, or the need for biologic drugs. Hierarchical clustering categorized disease severity at diagnosis based on complete blood count, albumin, C-reactive protein and erythrocyte sedimentation rate (ESR), analyzed together. Results A total of 13 471 patients with UC (1427 [11%] pediatric-onset) including 103 212 person-years of follow-up were included. Complicated disease course was recorded in 2829 (21%) patients: 1052 (7.9%) escalated to biologics, 1357 (10%) experienced steroid-dependency, and 420 (3.1%) underwent colectomy. Probabilities of complicated disease course at 1 and 5 years from diagnosis were higher in pediatric-onset (11% and 32%, respectively) than adult-onset disease (4% and 16%; P < .001). In a Cox multivariate model, complicated course was predicted by induction therapy with steroids (hazard ratio [HR], 1.5; 95% CI, 1.2-2.0), extraintestinal manifestations (HR, 1.3; 95% CI, 1.03-1.5) and the disease severity clusters of blood tests (HR, 1.8; 95% CI, 1.01-3.1), while induction therapy with enemas (HR, 0.6; 95% CI, 0.5-0.7) and older age (HR, 0.99; 95% CI, 0.98-0.99) were associated with noncomplicated course. Conclusion In this nationwide cohort, the probability of complicated disease course during the first 5 years from diagnosis was 32% in pediatric-onset and 16% in adults with UC and was associated with more severe clusters of routinely collected laboratory tests, younger age at diagnosis, extraintestinal manifestations, and type of induction therapy.