The effect of Share 35 on biliary complications: An interrupted time series analysis

Abstract

The purpose of the Share 35 allocation policy was to improve liver transplant waitlist mortality, targeting high MELD waitlisted patients. However, policy changes may also have unintended consequences that must be balanced with the primary desired outcome. We performed an interrupted time series assessing the impact of Share 35 on biliary complications in a select national liver transplant population using the Vizient CDB/RM database. Liver transplants that occurred between October 2012 and September 2015 were included. There was a significant change in the incident-rate of biliary complications between Pre-Share 35 (n = 3018) and Post-Share 35 (n = 9984) cohorts over time (P =.023, r 2  =.44). As a control, a subanalysis was performed throughout the same time period in Region 9 transplant centers, where a broad sharing agreement had previously been implemented. In the subanalysis, there was no change in the incident-rate of biliary complications between the two time periods. Length of stay and mean direct cost demonstrated a change after implementation of Share 35, although they did not meet statistical difference. While the target of improved waitlist mortality is of utmost importance for the equitable allocation of organs, unintended consequences of policy changes should be studied for a full assessment of a policy's impact.