Simultaneous Liver-kidney Versus Liver Transplantation Categorized by Pretransplant eGFR: Impact of the 2017 OPTN...

Simultaneous liver-kidney transplantation (SLKT) has increased substantially in the United States since adoption of the Model for End-stage Liver Disease-based allocation, now comprising 9%-10% of liver transplants. The survival benefit of SLKT compared with liver transplantation alone (LTA) remains uncertain.

Using the Organ Procurement and Transplant Network (OPTN)/United Network for Organ Sharing registry, we analyzed 63 407 adult liver transplants (57 780 LTA; 5627 SLKT) performed between 2010 and 2019. Patient survival was evaluated across pretransplant estimated glomerular filtration rate (eGFR) categories and according to transplant era before and after implementation of the 2017 OPTN policy.

Among patients with pretransplant eGFR ≥30 mL/min/1.73 m 2 , SLKT conferred no survival benefits, and LTA recipients achieved comparable or better long-term outcomes. In contrast, SLKT significantly reduced mortality in patients with advanced renal dysfunction. For eGFR 15-29 mL/min/1.73 m 2 , SLKT reduced 1-, 3-, and 5-y mortality by 25%, 15%, and 13%, respectively. For eGFR <15 mL/min/1.73 m 2 , SLKT reduced 1-, 3-, 5-, and 10-y mortality by 32%, 24%, 22%, and 17%, respectively. Following implementation of the 2017 OPTN policy and "Safety Net" policies, SLKT procedures declined. The survival advantage of SLKT observed in the pre-policy era was no longer evident post-policy, with 1.4% of LTA recipients undergoing kidney after liver transplantation under "Safety Net" allocation priority.

SLKT is associated with survival benefit in patients with severe renal dysfunction (eGFR <30 mL/min/1.73 m 2 ). Following implementation of the 2017 OPTN policy, this survival difference was no longer evident, and SLKT procedures were reduced without compromising survival. These findings support a stage-specific allocation strategy incorporating the "Safety Net" framework.