PHILADELPHIA—A 30% or greater decline in estimated glomerular filtration rate (eGFR) between years 1 and 3 after kidney transplantation is associated with an increased risk of graft-censored graft failure and patient death, data presented at the 2015 American Transplant Congress suggest.

This magnitude of decline in eGFR potentially may be useful as a surrogate marker in clinical trials looking at the impact of interventions to prevent these outcomes, according to co-investigator Steven J. Chadban, MBBS, PhD, who presented study findings.

Using data from the Australia and New Zealand Dialysis and Transplant Registry, researchers studied 7,949 kidney transplants performed from 1995–2009 who were followed up for a total of 71,845 patient-years. Recipients experienced 1,121 graft losses and 1,192 deaths. Between years 1 and 3 post-transplant, 10% of patients experienced at least a 30% decline in eGFR. This decline was associated with a 6-fold increased risk in death-censored graft loss and a 2.3 times increased risk of patient death compared with stable eGFR.

Greater rates of eGFR decline were associated with progressively higher risks of these outcomes, according to the investigators.

The findings of the new study echo those of a study looking at how eGFR decline affects the subsequent risk of end-stage renal disease (ESRD) and mortality in patients with chronic kidney disease (CKD). The study, published in the Journal of the American Medical Association (2014;311:2518-2531), found that a 30% or greater decline in eGFR from a baseline of less than 60 mL/min/1.73 m² over 2 years was associated with an increased risk of both outcomes in adjusted analyses.

Dr. Chadban said he and his colleagues concluded that a 30% decline in post-transplant eGFR over 2 years is common and strongly associated with hard outcomes, “and given the fact that it very much mirrors the hard data from CKD, we would propose this as a potential surrogate outcome for future trials in kidney transplantation.”

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