Epidemiology and implications of concurrent diagnosis of eosinophilic oesophagitis and IBD based on a prospective population-based analysis

Objective Eosinophilic oesophagitis (EoO) and IBD are immune-mediated diseases of the gastrointestinal tract with possible overlapping pathogenic mechanisms. Our aim was to define the epidemiology and clinical implications of concurrent EoO and IBD diagnoses. Design We conducted a prospective cohort analysis using the Truven MarketScan database (2009-2016) to estimate the incidence and prevalence of EoO in patients with Crohn's disease (CD) or UC and vice versa. Cox proportional hazards and Kaplan-Meier methods were used to estimate the risk of EoO-related or IBD-related complications among patients with concurrent diagnoses. Results Among 134 013 536 individuals, the incidence of EoO, CD and UC were 23.1, 51.2 and 55.2 per 100 000 person-years, respectively. The risk of EoO was higher among patients with CD (incidence rate ratio [IRR] 5.4, p<0.01; prevalence ratio (PR) 7.8, p<0.01) or UC (IRR 3.5, p<0.01; PR 5.0, p<0.01), while the risk of IBD was higher among patients with EoO (CD: IRR 5.7, p<0.01; PR 7.6, p<0.01; UC: IRR 3.4, p<0.01; PR 4.9, p<0.01) versus individuals without either diagnosis. Concurrent diagnosis of EoO and IBD was associated with greater composite risk of IBD-related complications (CD: adjusted HR (aHR) 1.09, p=0.01; UC: aHR 1.10, p=0.04) but lower composite risk of EoO-related complications (aHR 0.59; p<0.01). Conclusion Based on a population-based prospective cohort analysis, the risk of EoO is significantly higher among patients with IBD and vice versa. Concurrent diagnoses might modify the risk of IBD-related and EoO-related complications. Studies defining the mechanisms underlying these observations are needed.