Yale Center for Analytic Sciences, Yale School of Public Health, New Haven, Connecticut.
United Network for Organ Sharing, Richmond, Virginia.
J Am Soc Nephrol. 2022 Aug;33(8):1613-1624. doi: 10.1681/ASN.2022010078. Epub 2022 May 10.
Performance of kidney transplant programs in the United States is monitored and publicly reported by the Scientific Registry of Transplant Recipients (SRTR). With relatively few allograft failure events per program and increasing homogeneity in program performance, quantifying meaningful differences in program competency based only on 1-year survival rates is challenging.
We explored whether the traditional end point of allograft failure at 1 year can be improved by incorporating a measure of allograft function (, eGFR) into a composite end point. We divided SRTR data from 2008 through 2018 into a training and validation set and recreated SRTR tiers, using the traditional and composite end points. The conditional 5-year deceased donor allograft survival and 5-year eGFR were then assessed using each approach.
Compared with the traditional end point, the composite end point of graft failure or eGFR <30 ml/min per 1.73 m at 1-year post-transplant performed better in stratifying transplant programs based on long-term deceased donor graft survival. For tiers 1 through 5 respectively, the 5-year conditional graft survival was 72.9%, 74.8%, 75.4%, 77.0%, and 79.7% using the traditional end point and 71.1%, 74.4%, 76.9%, 77.0%, and 78.4% with the composite end point. Additionally, with the five-tier system derived from the composite end point, programs in tier 3, tier 4, and tier 5 had significantly higher mean eGFRs at 5 years compared with programs in tier 1. There were no significant eGFR differences among tiers derived from the traditional end point alone.
This proof-of-concept study suggests that a composite end point incorporating allograft function may improve the post-transplant component of the five-tier system by better differentiating between transplant programs with respect to long-term graft outcomes.
美国的肾脏移植项目的表现由移植受者科学注册处（SRTR）进行监测和公开报告。由于每个项目的同种异体移植物失败事件相对较少，并且项目表现的同质化程度越来越高，仅基于 1 年生存率来量化项目能力方面的有意义差异具有挑战性。
我们探讨了是否可以通过将同种异体移植物功能（eGFR）的测量值纳入复合终点来改进 1 年的同种异体移植物失败的传统终点。我们将 2008 年至 2018 年的 SRTR 数据分为训练集和验证集，并使用传统和复合终点重新创建了 SRTR 分层。然后，使用每种方法评估条件性 5 年死亡供体移植物存活率和 5 年 eGFR。
与传统终点相比，移植后 1 年移植物衰竭或 eGFR<30ml/min/1.73m 的复合终点在根据长期死亡供体移植物存活率对移植项目进行分层方面表现更好。分别使用传统终点和复合终点，第 1 层至第 5 层的 5 年条件移植物存活率分别为 72.9%、74.8%、75.4%、77.0%和 79.7%，71.1%、74.4%、76.9%、77.0%和 78.4%。此外，使用复合终点衍生的五级系统，第 3 级、第 4 级和第 5 级的方案在 5 年内的平均 eGFR 明显高于第 1 级。仅使用传统终点衍生的层次之间没有明显的 eGFR 差异。
这项概念验证研究表明，纳入同种异体移植物功能的复合终点可能通过更好地区分长期移植物结局方面的移植项目来改善五级系统的移植后部分。
