African American race does not confer an increased risk of clinical events in patients with primary sclerosing cholangitis

Background: The natural history of primary sclerosing cholangitis (PSC) among African Americans (AA) is not well understood. Methods: Transplant-free survival and hepatic decompensation-free survival were assessed using a retrospective research registry from 16 centers throughout North America. Patients with PSC alive without liver transplantation after 2008 were included. Diagnostic delay was defined from the first abnormal liver test to the first abnormal cholangiogram/liver biopsy. Socioeconomic status was imputed by the Zip code. Results: Among 850 patients, 661 (77.8%) were non-Hispanic Whites (NHWs), and 85 (10.0%) were AA. There were no significant differences by race in age at diagnosis, sex, or PSC type. Inflammatory bowel disease was more common in NHWs (75.8% vs. 51.8% p=0.0001). The baseline (median, IQR) Amsterdam-Oxford Model score was lower in NHWs (14.3, 13.4-15.2 vs. 15.1, 14.1-15.7, p=0.002), but Mayo risk score (0.03, -0.8 to 1.1 vs. 0.02, -0.7 to 1.0, p=0.83), Model for End-stage Liver Disease (5.9, 2.8-10.7 vs. 6.4, 2.6-10.4, p=0.95), and cirrhosis (27.4% vs. 27.1%, p=0.95) did not differ. Race was not associated with hepatic decompensation, and after adjusting for clinical variables, neither race nor socioeconomic status was associated with transplant-free survival. Variables independently associated with death/liver transplant (HR, 95% CI) included age at diagnosis (1.04, 1.02-1.06, p<0.0001), total bilirubin (1.06, 1.04-1.08, p<0.0001), and albumin (0.44, 0.33-0.61, p<0.0001). AA race did not affect the performance of prognostic models. Conclusions: AA patients with PSC have a lower rate of inflammatory bowel disease but similar progression to hepatic decompensation and liver transplant/death compared to NHWs.