Changes in medical treatment and surgery rates in inflammatory bowel disease: a nationwide cohort study 1979–2011

Abstract

Introduction Treatment possibilities have changed in inflammatory bowel disease (IBD). We assessed changes in medical treatment and surgery over time and impact of medications on risk of surgery in a population-based cohort. Methods 48 967 individuals were diagnosed with IBD (Crohn's disease (CD), 13 185; ulcerative colitis (UC), 35 782) during 1979–2011. Cumulative probability of receiving 5-aminosalicylic acids (5-ASA), topical, oral corticosteroids, thiopurines, and tumour necrosis factor-α (TNF-α) blockers, and of first minor or major surgery according to period of diagnosis, was estimated. Medication use and risk of surgery was examined by Cox regression. Results 5-year cumulative probability of first major surgery decreased from 44.7% in cohort (1979–1986) to 19.6% in cohort (2003–2011) (p < 0.001) for CD, and from 11.7% in cohort (1979–1986) to 7.5% in cohort (2003–2011) (p < 0.001) for UC. Minor surgery risk decreased significantly in CD. From cohort (1995–2002) to cohort (2003–2011), a significant increase in use of thiopurines and TNF-α blockers was observed, paralleled by a significant decrease in use of 5-ASA and corticosteroids. Comparing use of azathioprine (or oral corticosteroids) to never-use, no convincing surgery-sparing effect was found. Comparing use in 3+ months of a given drug with use 1 year. Conclusions Parallel to an increasing use of thiopurines and TNF-α blockers in IBD over time, a persistent significant decrease in surgery rates was observed along with a significant decrease in use of 5-ASA and corticosteroids. However, no convincing surgery-sparing effect of newer medications was found.