Introduction

There is a well-known association between inflammatory bowel disease (IBD) and primary sclerosing cholangitis (PSC). It is estimated that approximately 2% of IBD patients have PSC. However, there is little data regarding the impact of PSC on the prognosis of patients with IBD.

Aims & Methods

We conducted a retrospective cohort study using TriNetX, a multi-institutional database, to compare outcomes of patients with IBD and those with both IBD and concomitant PSC between 2003 and 2023. All patients with a confirmed diagnosis of Crohn's disease (CD), ulcerative colitis (UC), or indeterminate colitis with or without PSC were eligible. One-to-one propensity score matching was employed to balance demographic parameters, comorbid conditions, and IBD medications between cohort 1 (IBD) and cohort 2 (IBD and concomitant PSC). The primary endpoint was a composite endpoint including risk of mortality, hospitalization, and surgery. Secondary endpoints were the risk of mortality, IBD-related surgery, and IBD-related hospitalization. Risks were expressed as Hazard Ratio (HR) with a 95% confidence interval (CI).

Results

A total of 409,104 IBD patients were analyzed, including cohort 1 (405,923) and cohort 2 (3,181). After propensity score matching, 3007 patients from each group were included (mean age 48.1 ± 19.4 years, female 40%, UC 75%, CD 24,8%). Cohort 2 patients had an higher risk of experiencing the composite endpoint compared to cohort 1 group (HR 1.326, CI 1.232-1.428). Similarly, a higher risk of experiencing hospitalization and mortality was identified in subjects with IBD and concomitant PSC (HR 1.326, CI 1.224-1.436 and HR 1.697, CI 1.467-1.963 respectively). No difference was detected in terms of surgery between the two groups (HR 1.181, CI 0.970-1.438). Another analysis was performed to compare the outcomes of patients with CD or UC with or without concomitant PSC. Both CD and UC patients with concomitant PSC had an higher risk of achieving the composite endpoint (HR 1.186, CI 1.026-1.372 and HR 1.293, CI 1.189-1.408, respectively). An increased risk of mortality and hospitalization was found both in patients with CD (HR 2.164, CI 1.587-2.952, and 1.207, CI 1.031-1.412, respectively) and UC (HR 1.875, CI 1.578-2.228 and HR 1.279, CI 1.168-1.401, respectively) and concomitant PSC. In patients with CD or UC and concomitant PSC no increased risk of surgery was found (HR 0.954, CI 0.641-1.421 and HR 1.102, CI 0.886-1.369, respectively).

Conclusion

In the largest case series of patients with IBD and PSC, concomitant PSC increased risk of mortality and IBD-related hospitalization.