Age at disease onset of inflammatory bowel disease is associated with later extraintestinal manifestations and complications.

A small but increasing number of patients with inflammatory bowel disease are diagnosed during childhood or adolescence, and disease distribution and severity at onset vary according to the age at diagnosis. Clinical factors present at the time of diagnosis can be predictive of the disease course. The aim of this study was to characterize disease behavior and the cumulative complications and extraintestinal manifestations 10 years after the diagnosis and to assess their association with age at diagnosis. Data of patients participating with the Swiss IBD cohort study registry, a disease duration of 10 years and a complete data set were analyzed. The outcome was defined as the cumulative change of disease behavior, the occurrence of extra-intestinal manifestations or complications, and the necessity for medical or surgical interventions. A total of 481 patients with Crohn's disease (CD) and 386 patients with ulcerative colitis (UC), grouped according to disease onset before 10, 17, 40, or after 40 years of age, were analyzed. Despite differences in sex, initial disease location, and smoking habits, at 10 years after the diagnosis, no difference was found regarding disease behavior in CD or regarding progression of disease extension in UC. Similarly, no age-of-onset-dependent cumulative need for medical or surgical therapies was found. However, higher rates of anemia and lower rates of arthralgia and osteopenia were found in both pediatric-onset CD and UC, and a tendency toward higher rates of stomatitis in pediatric-onset CD, and of primary sclerosing cholangitis and ankylosing spondylitis in pediatric-onset UC. After 10 years of disease evolution, age at disease onset is not anymore associated with disease behavior but only with a small difference in the occurrence of specific extraintestinal manifestations and complications