Objective: The aim of the study was to use hospitalization data for the analysis of inflammatory bowel disease time trends in the United States.

Methods: US hospital utilization data were available for individual years from 1970 to 2004 through the National Hospital Discharge Survey. Age-specific rates of hospitalization were calculated for consecutive 5-year periods.

Results: An increase in the rates of hospitalization for Crohn's disease was most pronounced in the age group 65+ followed by the age group 45 to 64. By contradistinction, the rates in the youngest age group 0 to 44 stayed largely unchanged. In ulcerative colitis, a significant increase in hospitalization rates was limited to the oldest age group, whereas the rates in the middle and young age group remained unchanged.

Conclusions: Extrapolation of the current trends suggests that in the future the hospitalization for inflammatory bowel disease may start to level off. This may occur earlier and be more pronounced in younger age groups and patients with ulcerative colitis than Crohn's disease.