Factors Associated With Long-term Kidney Allograft Survival: A Contemporary Analysis of the UNOS Database.

Abstract

Background: Various clinicopathologic markers, such as 1-year serum creatinine (Cr), have been used to prognosticate kidney allografts after transplantation. However, a contemporary analysis of their relationship with long-term graft survival is lacking. This study aimed to analyze recent data on the association of prognostic factors with kidney allograft survival in patients who underwent transplantation in the modern era.

Methods: Adult kidney-transplant recipients in the UNOS database (2008-2020) were identified. Living and deceased donor allografts were analyzed separately and stratified by 1-year serum Cr level: ≤1.0, 1.0 to 1.5, 1.5 to 2.0, and >2.0 mg/dL. Time-to-event analysis was performed with long-term death-censored graft survival as the primary outcome. In addition, factors associated with raised 1-year serum Cr and with long-term allograft failure were identified.

Results: 174,547 patients were included. Ten-year survival decreased with increasing 1-year creatinine, and these trends persisted on adjusted analysis for both living donor (Cr ≤ 1.0 mg/dL: reference; Cr 1.0-1.5 mg/dL aHR = 1.77 [1.59-1.96]; Cr 1.5-2.0 mg/dL aHR = 3.24 [2.89-3.64] and; Cr > 2.0 mg/dL aHR = 9.78, [8.64-11.07], P < .01) as well as deceased donor allografts (Cr ≤ 1.0 mg/dL: reference; Cr 1.0-1.5 mg/dL aHR = 1.74 [1.63-1.86]; Cr 1.5-2.0 mg/dL aHR = 3.06 [2.84-3.30] and; Cr > 2.0 mg/dL aHR = 8.51, [7.89-9.18], P < .01).

Conclusion: These results characterize the association between 1-year serum creatinine levels and other clinicopathologic factors with long-term kidney allograft survival. We demonstrate the ability of prognostic factors to stratify patients by risk of graft failure in a contemporary patient cohort that is representative of current practice and outcomes.