Association of age at diagnosis and Crohn's disease phenotype

Objective: to compare disease behaviour in patients with CD based on age at diagnosis. Design: cross-sectional study. Setting: tertiary referral centre. Subjects: patients with confirmed CD. Methods: behaviour was characterised according to the Montreal classification. Patients with either stricturing or penetrating disease were classified as having complicated disease. Age at diagnosis was categorised as < 17, 17-40, 41-59 and >= 60 years. Logistic regression analysis was performed to examine the association between advanced age >= 60 and complicated disease. Results: a total of 467 patients were evaluated between 2004 and 2010. Increasing age of diagnosis was negatively associated with complicated disease and positively associated with colonic disease. As age of diagnosis increased, disease duration (P < 0.001), family history of Inflammatory bowel disease (IBD) (P = 0.015) and perianal disease decreased (P < 0.0015). After adjustment for confounding variables, the association between age at diagnosis and complicated disease was no longer significant (OR: 0.60, 95% CI: 0.21-1.65). Conclusions: patients diagnosed with CD >= 60 were more likely to have colonic disease and non-complicated disease. However, the association between age at diagnosis and complicated disease did not persist after adjustment for confounding variables.