Association Between Institutional Factors and Long-Term Survival Following Transjugular Intrahepatic Portosystemic Shunt

Abstract

Transjugular intrahepatic portosystemic shunt (TIPS) is a procedure designed to treat portal hypertension. Hospital teaching status is an institutional factor found to be predictive of outcomes following several complex procedures; however, its impact on outcomes following TIPS is unknown. The aim of this study was to determine the association between hospital teaching status and long-term survival in patients with cirrhosis receiving TIPS. We performed a retrospective population-based cohort study using linked administrative health data from Ontario, Canada. Adult patients with cirrhosis who received TIPS between January 1, 1998, and December 31, 2016, with follow-up until December 31, 2017, were included. Hospital teaching status was defined based on hospital participation in the instruction of medical students and/or resident physicians. Liver transplant-free (LTF) survival was evaluated using Kaplan-Meier analysis, and overall survival was assessed using competing risks regression analysis, which accounted for hospital clustering. A total of 857 unique patients were included (mean age 57.1 years; 69.1% male). The TIPS procedures were performed in teaching hospitals (84.3%) as well as nonteaching hospitals (15.7%). Median LTF survival was more than twice as long for procedures performed in teaching hospitals compared to nonteaching hospitals (2.2 years versus 0.9 year, respectively; P < 0.001). After adjusting for confounders and clustering, hospital teaching status was not independently associated with mortality (nonteaching subdistribution hazard ratio [sHR], 1.32; 95% confidence interval [CI], 0.97-1.81; P = 0.08); however, annual hospital procedure volume was (per unit increase sHR, 0.96; 95% CI, 0.93-0.99; P = 0.003). Conclusion: Hospital procedure volume is associated with long-term survival following TIPS. These results further support the centralization of TIPS to high-volume hospitals to improve long-term outcomes in this population.