In this cohort, immunological therapy was initiated within the first months of disease. Surgery and hospitalization rates did not differ between patients from eastern and western Europe, although more western European patients received biological agents and were comparable to previous population-based inception cohorts.

In this European population-based inception cohort of unselected IBD patients, Eastern and Western European patients differed in environmental factors prior to diagnosis. Eastern European patients exhibited higher occurrences of suspected risk factors for IBD included in the Western lifestyle.

In this population-based unselected cohort, costs during the first year of disease were mainly incurred by investigative procedures and surgeries. However, biologicals accounted for >15% of costs. Long-term follow-up of the cohort is needed to assess the cost-effectiveness of biological agents.