Objective: To study changes in treatment and disease course in patients with Crohn's disease (CD) in the South Limburg region of the Netherlands between 1991 and 2014.
Design: Population-based cohort study.
Methods: All 1162 CD patients in the 'IBD South Limburg cohort' were divided across three subcohorts on the basis of year of diagnosis: 1991-1998 (N = 316), 1999-2005 (N = 387) and 2006-2011 (N = 459). We compared the risk of hospitalization, bowel resection and the development of strictures and/or fistulas across the subcohorts. We also compared cumulative corticosteroid use and the relationship between the outcome measures and maintenance medication.
Results: In the period 1991-2014 there was an increase in the number of patients treated within 5 years with immunomodulators from 30.6% to 70.8%. For treatment with biologicals there was an increase from 3.1% to 41.2%. In parallel, the risk of hospitalization decreased from 65.9% to 44.2% and the risk of bowel resection decreased from 42.9% to 17.4%. The risk of developing strictures or fistulas remained stable (21.2%). There was no significant association between the outcome measures and the use of immunomodulators or biologicals. Furthermore, corticosteroid use decreased over time; this was linked to use of immunomodulators and biologicals.
Conclusion: Treatment of Crohn's disease has changed over the past two decades, and the disease course has improved. We found no association between changes in maintenance medication and disease course.