Risk of avascular necrosis in patients with inflammatory bowel disease: Insights from a nationwide cohort study and the impact of corticosteroid use

Background and aim: Corticosteroid use is a risk factor for avascular necrosis (AVN) and inflammatory bowel disease (IBD) patients are often exposed to higher corticosteroid usage. We investigated the epidemiology and risk factors of AVN in a nationwide population-based cohort of IBD patients.

Methods: Patients newly diagnosed with IBD were identified, and sex- and age-matched participants from the general population were selected in a 1:3 IBD:non-IBD ratio. We investigated newly diagnosed AVN and assessed the incidence rates and risk of AVN with multivariate Cox regression models.

Results: During the median follow-up period of 7.22±3.85 years, 357 (0.62 %) were newly diagnosed with AVN. The risk of AVN was higher in IBD (aHR = 1.42, 95 % CI: 1.25-1.62). Ulcerative colitis (UC) patients showed a particularly elevated risk of developing AVN. IBD patients with higher cumulative corticosteroid intake and exposed to a mean prednisolone-equivalent daily dose>20 mg for >1 month were at higher risk of AVN. In Crohn's disease (CD), longer exposure time to >20 mg prednisolone-equivalent presented a trend in increased risk.

Conclusion: AVN risk was higher in IBD than in those without, particularly in UC and corticosteroid use in IBD could pose a crucial role. These underscore the importance of considering the AVN etiological factors, particularly corticosteroid use.