Does kidney transplantation with a standard or expanded criteria donor improve patient survival? Results from a Belgian cohort

Background: Changes in recipient and donor factors have reopened the question of survival benefits with kidney transplantation versus dialysis. Methods: We analyzed survival among 3808 adult Belgian patients waitlisted for a first deceased donor kidney transplant from 2000 to 2012. The primary outcome was mortality during the median waiting time plus 3 years of follow-up after transplantation or with continued dialysis. Outcomes were analyzed separately for standard criteria donor (SCD) and expanded criteria donor (ECD) kidney transplants. We adjusted survival analyses for recipient age (20-44 y, 45-64 y, ≥65 y), sex, and diabetes as primary renal disease. Results: Among patients aged ≥65 years, only SCD transplantation provided a significant survival benefit compared to dialysis, with a mortality of 16.3% (95% confidence interval 13.2%-19.9%) with SCD transplantation, 20.5% (16.1%-24.6%) with ECD transplantation, and 24.6% (19.4%-29.5%) with continued dialysis. Relative mortality risk was increased in the first months after transplantation compared to dialysis, with equivalent risk levels reached earlier with SCD than ECD transplantation in all age groups. Discussion: The results of this study suggest that older patients might gain a survival benefit with SCD transplantation versus dialysis, but any survival benefit with ECD transplantation versus dialysis may be small.