Primary sclerosing cholangitis-inflammatory bowel disease: epidemiology, mortality, and impact of diagnostic sequence

Background and aims — Primary sclerosing cholangitis (PSC) carries significant morbidity and mortality compared with inflammatory bowel disease (IBD). We characterized epidemiology trends and outcomes in those with PSC-IBD and IBD, paying particular attention to the impact of PSC-IBD diagnostic sequence on outcomes.

Methods — Incidence and prevalence of PSC-IBD and IBD (2002–2018) were evaluated using validated health administrative data-derived cohorts from Ontario, Canada (population ∼15 million). Transplant and death outcomes were assessed, with PSC-IBD diagnostic sequence as the exposure of interest.

Results — Incidence of PSC-IBD and IBD was 0.46 and 24.6/100,000 person-years (PYs) respectively, whereas prevalence was 5.53 and 588/100,000 PY respectively. Incidence/prevalence of PSC-IBD increased over time, unlike for IBD. Age at IBD diagnosis was earlier among those with PSC-IBD compared with those with IBD alone. Higher socioeconomic status associated with high PSC-IBD incidence rates and fastest incidence rise. Those diagnosed with IBD before PSC had higher risk of transplant/death compared with PSC before IBD (hazard ratio [HR] 1.34, 95% CI 1.02–1.75), driven by an increased risk of death (HR 2.73, 95% CI 1.68–4.45). PSC-IBD had a 4.5-fold greater risk of transplant/death compared with IBD alone. Liver-related and luminal gastrointestinal disease, particularly hepatopancreatobiliary malignancy, were predominant causes of death among those with PSC-IBD, while cardiovascular and respiratory diseases were predominant among those with IBD.

Conclusions — Population-level data support distinct epidemiological patterns among people living with PSC-IBD compared with IBD, including a higher socioeconomic status and worse outcomes in those found to have IBD before PSC.