Comorbidities in adolescents with inflammatory bowel disease: findings from a population-based cohort study

Background Inflammatory bowel diseases are associated with various immune- and non-immune-mediated conditions. We aimed to assess the association of inflammatory bowel diseases with comorbidities at late adolescence. Methods Jewish Israeli adolescents who underwent a general health evaluation prior to enlistment to the Israeli Defense Forces from 2002 to 2016 were included. Results Overall, 891 subjects (595 Crohn's disease, 296 ulcerative colitis, median age 17.1 years) and 1,141,841 controls were analyzed. Crohn's disease was associated with arthritis (odds ratio (OR) 4.7, 95% confidence interval (CI) 2.4-9.1), thyroid disease (OR 2.6, 95% CI 1.2-5.5), atopic dermatitis (OR 2, 95% CI 1.1-3.6), autoimmune hepatitis (OR 4.4, 95% CI 2.3-8.6), nephrolithiasis (OR 3.6, 95% CI 1.2-11.4), and pancreatitis (OR 41.8, 95% CI 17.2-101.9). Ulcerative colitis was associated with arthritis (OR 3.6, 95% CI 1.0-9.8), thyroid disease (OR 4.8, 95% CI 1.2-19.4), autoimmune hepatitis (OR 8, 95% CI 4-16.2), and pancreatitis (OR 51, 95% CI 16.1-158.9). Primary sclerosing cholangitis was associated with both diseases. Asthma, celiac, type 1 diabetes, psoriasis, and bone fractures were not more common in both diseases. Male predominance was noted for most associations. Conclusions At adolescence, both Crohn's disease and ulcerative colitis are associated with multiple comorbidities, not limited to autoimmune disorders.