Different trends in intestinal and perianal surgery rates in patients with Crohn’s disease in Austria: A nationwide population-based study

BACKGROUND: Despite an increasing number of biological therapies, publications report conflicting surgery rates in Crohn's disease (CD). AIMS: To examine trends in the rates of surgeries for intestinal and perianal fistulizing CD in the era of biologics in Austria. METHODS: In this nationwide population-based study patients with a diagnosis of CD and CD-related intestinal or perianal surgeries between 2011 and 2019 were included. Data were retrospectively retrieved from the Austrian Health Insurance Funds. Absolute numbers of CD-related surgeries per year and per 100,000 Austrians were calculated and changes during the observation period compared with estimates of the CD prevalence. RESULTS: A cohort of 6,593 patients with CD underwent a total of 4,758 intestinal and 4,794 perianal surgeries from 2011 through 2019. Intestinal surgery rates remained stable with 5.9 vs. 6.0/100,000 Austrians and perianal surgeries rose from 5.0 to 7.5/100,000, equalling an annual increase of 0.2% and 5.2%, respectively, whereas the prevalence of CD rose by 3.2% annually (95% confidence interval 1.9 - 4.6). CONCLUSION: In Austrian CD patients intestinal resection rates remained stable, whereas perianal fistula surgeries increased. Adjustment for rising CD prevalence revealed fewer intestinal resections per CD patient years, while perianal fistula surgery rates continued to increase.