Increased Risk of Cirrhosis in Patients with Inflammatory Bowel Disease: A Danish registry-based cohort study (1998-2018)

Background and Aims Prior studies suggest an increased risk of non-alcoholic fatty liver disease (NAFLD) in patients with inflammatory bowel disease (IBD). We aimed to investigate the risk of cirrhosis in a nationwide cohort of IBD patients compared to a matched non-IBD population. Methods Patients diagnosed with IBD without prior cirrhosis during 1998-2018 were identified in the Danish health registries and were matched 1:10 to persons without IBD. Cox regression was used to calculate hazard ratios (HRs) with corresponding 95% confidence intervals (CIs). Results Within the study population of 495,220 persons, a total of 2,741 cirrhosis cases were identified during follow-up, with a higher proportion of cases among patients with IBD (0.9%) compared to non-IBD persons (0.5%). Patients with IBD had a significantly higher risk of cirrhosis compared to non-IBD persons (adjusted HR (aHR) (95% CI): 1.84 (1.64-2.04)). The leading etiology of cirrhosis in IBD was NAFLD (51.6%), followed by alcohol (39.0%). The risk of cirrhosis among IBD patients (compared to non-IBD persons) was more pronounced among those diagnosed with IBD ≤ 40 years of age (aHR (95% CI): 3.08 (2.45-3.87); vs. > 40 years of age, 1.63 (1.45-1.84); p-value <0.001) and CD patients (aHR (95% CI): 2.20 (1.80-2.67); vs. 1.72 (1.52-1.95) among UC; p-value 0.04). Conclusion IBD was associated with an increased risk of incident cirrhosis, especially in patients aged ≤ 40 years at IBD diagnosis and in patients with CD. These findings point towards a need for focused screening for cirrhosis among IBD patients, especially in certain groups.