Background: Fistulae and stenoses represent frequent and severe complications in patients with Crohn's disease (CD). For an optimal treatment it would be helpful to identify factors being predictive for the development of CD-associated fistulae and stenoses to guide the clinical management or, ideally, prevent their occurrence. Our study therefore aimed to identify risk factors for fistulae and stenosis formation in CD patients.
Methods: We retrieved data of 1'600 CD patients from the nationwide Swiss IBD cohort study (SIBDCS). The risk of fistulae and stenoses in relation to gender, age at diagnosis, smoking status at diagnosis and ileal involvement at diagnosis were analyzed.
Results: In the multivariate analysis female gender showed a lower risk for developing perianal and any fistula (RR 0.721, 95% CI 0.582–0.893, p=0.003 and RR 0.717, 95% CI 0.580–0.888, p=0.002, respectively) and older age at diagnosis showed a lower risk for developing perianal fistula (RR 0.661, 95% CI 0.439–0.995, p=0.047). Furthermore, ileal involvement was associated with a lower risk for perianal fistula (RR 0.713, 95% CI 0.561–0.906, p=0.006), a lower risk for any fistula (RR 0.709, 95% CI 0.558–0.901, p=0.005) and a higher risk for stenoses (RR 2.170, 95% CI 1.728–2.725, p<0.001).
Conclusions: In the nationwide Swiss IBD cohort younger age at diagnosis and male gender were risk factors developing perianal and non-perianal fistulae. Additionally, ileal involvement revealed to be a potent risk factor (RR 2.170) to develop stenoses.