The listing policy for simultaneous liver-kidney transplantation issued on July 10, 2017, imposed more stringent criteria on recipient renal function. Data on recipient outcomes following the change are scarce. M. L. Samoylova and colleagues at Duke University Hospital, Durham, North Carolina, conducted an analysis to examine outcomes prior to and following the policy change.
Results of the analysis were reported during a virtual presentation at the American Transplant Congress 2020. The presentation was titled Utilization and Outcomes of Simultaneous Liver-Kidney Transplants after Change in Allocation Policy.
Data from the United Network for Organ Sharing database were used to identify adult recipients of simultaneous liver-kidney transplant from 2007 to 2018. The patients were stratified into three eras: 2007 to 2011; 2012 to July 10, 2017, (policy change); and July 11, 2017, to July 2018. The researchers used Chi-squared test and multivariable Cox proportional hazard models to compare patient and graft survival at 1 year.
During the three eras, a total of 5809 patients received simultaneous liver-kidney transplantation: 1892 in the 2007 to 2011 era, 3004 in the 2012 to July 10, 2017, era, and 913 in the July 11, 2017, to July 2018 era. Median donor age and Kidney Donor Profile Index were similar among the three eras (35 years, 33 years, and 34 years, respectively, P=.33 and 1.05, 1.04.and 1.06, respectively; P=.01).
Over time, the number of Expanded Criteria Donors decreased (10%, 8%, and 7%, respectively). There was no change in the proportion of patients on hemodialysis while on the transplant waitlist over time (72.5% vs 72.6% vs 73,0%, respectively, P=.96). There was also no change in mean estimated glomerular filtration rate at transplant among those not on hemodialysis (21.7 mL/min/1.72 m2 vs 21.2 mL/min/1.73 m2 vs 21.2 mL/min/1.73 m2, respectively, P=.83).
Between the first two eras, 1-year survival improved and then remained unchanged following the policy change (85% vs 90% vs 91%, respectively, P=.37). Trends for liver and kidney graft survival were similar.
In multivariable models, there was no difference in survival at 5 years pre-policy versus post-policy (hazard ratio [HR], 1.24; 95% confidence interval, [CI] 0.96-1.60; P=.10). The models did suggest an increased hazard of liver graft failure within the first year (HR, 1.28; 95% CI, 1.01-1.63; P=.047).
In conclusion, the researchers said, “Recipient renal function at transplant appears unchanged after the change in simultaneous liver-kidney transplantation listing policy. Despite concern that the policy change would select for sicker recipients and result in poor outcomes, short-term outcomes are similar to prior. Further attention is necessary to the factors affecting outcomes of liver grafts and center-level differences in practice.”
Source: Samoylova ML, Shaw BI , Kesseli SJ, et al. Utilization and outcomes of simultaneous liver-kidney transplants after changes in allocation policy. Abstract of a presentation at the virtual American Transplant Congress 2020 (Abstract 580), May 30, 2020.