Background: The disparity between donor kidney availability and demand has increased utilization of kidneys from older living donors (OLD). We compared graft and patient outcomes of patients on maintenance dialysis after transplantation with OLD kidneys to those receiving younger live donor (YLD) kidneys and deceased donor (DD) kidneys.
Methods: Using Australia and New Zealand Dialysis and Transplant Registry, primary live and deceased donor renal transplant recipients aged 18 years or older between 1997 and 2009 were stratified into six groups: standard criteria deceased donor kidneys with total ischemic time of less than 12 hours (SCD, <12), SCD of 12 or greater, expanded criteria donor (ECD) less than 12, ECD of 12 or greater, YLD (LD, <60 years), and OLD kidneys (LD, ≥60 years). Preemptive and multiple-organ transplants were excluded.
Results: Of the 6,317 renal transplant recipients, 346 (5.5%) received OLD kidneys. Compared with kidneys from SCD of less than 12 hours, OLD kidneys were associated with a greater risk of death-censored graft failure (DCGF; adjusted HR 2.00; 95% confidence interval, 1.32-3.03) and inferior 5-year graft function (estimated glomerular filtration rate of 45 mL/min vs. 56 mL/min), although no increase in 5-year mortality (HR, 1.18; 95% confidence interval, 0.80-1.76). Outcomes for OLD kidneys were also inferior to YLD recipients, although modestly superior to ECD kidneys. Chronic allograft nephropathy was more commonly reported as the cause of DCGF among recipients of OLD kidneys than other donor types.
Conclusion: Patient survival was equal, but graft outcomes for recipients of OLD kidneys were inferior to those obtained with YLD and SCD kidneys. This study suggests that OLD kidneys should be utilized cautiously, cognizant of the fact that younger recipients may have a life expectancy in excess of the life of the transplanted kidney.