A Paired Kidney Analysis of Multiorgan Transplantation

This is the authors' abstract. We don't add key points for this paper.

In Brief Background United Network for Organ Sharing multiorgan transplantation allocation policy allows sequestration of a kidney by another solid organ regardless of the priority of the candidate for the kidney allograft. The implications of this policy for kidney allograft survival are not well understood. Methods We conducted a retrospective cohort analysis of pairs of deceased donor kidney transplants where 1 kidney was allocated to a simultaneous liver-kidney (SLK) or simultaneous heart-kidney (SHK) recipient and the contralateral kidney to a kidney transplant alone (KTA) recipient (cohort from February 2002 to December 2010). Graft and patient survivals were assessed with Cox regression models. Results There were 1998 SLK and 276 SHK transplants with matching KTA transplants. Five-year kidney graft (64% [SLK] vs 75% [KTA], P < 0.001) and patient survivals (66% [SLK] vs 81% [KTA], P < 0.001) were significantly lower in SLK versus KTA recipients of the contralateral kidney. Among the entire cohort of SLK in this analysis, the cumulative difference in graft survival 1 year after transplant was 115 years, and by 5 years, the difference increased to 1062 years. Among the SHK arm of our study, 5-year graft survival (72% [SHK] vs 73% [KTA], P = 0.71) did not significantly differ, although patient survival (75% [SHK] vs 84% [KTA], P = 0.02) was higher in KTA recipients. Conclusions Kidney graft survival is inferior among SLK relative to KTA, but not SHK. Multiorgan transplantation allocation may not be congruent with the intention of new kidney allocation policies that attempt to maximize survival after kidney transplantation. This paired-kidney analysis of the UNOS/OPTN data of kidney transplant patients transplanted between 2002 and 2010 shows that kidney allograft survival in simultaneous liver-kidney transplantation is inferior to kidney transplant alone; whereas kidney allograft survival in simultaneous heart-kidney transplantation is not inferior to kidney transplant alone.