Background: The Vienna classification of Crohn's disease (CD) distinguishes three patient subgroups according to disease behavior: stricturing, penetrating, and inflammatory. Our aim was to assess the long-term evolution of the disease behavior of CD and to determine the predictive factors and prognostic implications of this evolution.
Methods: Occurrence and predictive factors of a stricturing and/or a penetrating complication were searched for in 2,002 patients with CD studied retrospectively. In addition, the 1995-2000 disease course was assessed prospectively in a cohort of 646 patients with disease duration >5 years, classified according to their previous disease behavior.
Results: 1,199 patients (60%) developed a stricturing (n = 254) or a penetrating (n = 945) complication. Twenty-year actuarial rates of inflammatory, stricturing, and penetrating disease were 12, 18, and 70%, respectively. The initial location of lesions was the main determinant of the time and type of the complication. In the cohort study, year-by-year activity and therapeutic requirements did not show significant sustained differences between behavioral subgroups.
Conclusion: Most patients with CD will eventually one day develop a stricturing or a perforating complication. Initial location determines the type of the complication. Classification of patients into a behavioral group from previous history has no impact upon activity during the following years.