Survival modelling in kidney transplantation: hazard rates of graft loss. Transplant Working Group of the Registry Committee of the European Dialysis and Transplantation Association-European Renal Association (EDTA-ERA).

Mathematical modelling of survival data provides long-term projection of graft survival and allows evaluation of the impact of several variables on graft outcome. We analysed 52,315 first cadaveric grafts performed between 1971 and 1985 and reported to the EDTA Registry. We quantified the risk of graft loss using the hazard rates. The hazard function provides the magnitude of the risk of graft loss at a given time post-transplantation. For the 1971 and the 1985 cohorts, the risk of graft loss at 1 month posttransplantation was 143 and 53 per 1000 patient-months, respectively. At 1 year it was 5 and 2.4 per 1,000, respectively. The hazard function thus allowed quantification of the magnitude of the risk of graft loss and its evolution along with time. At 5 years posttransplantation, the risk of graft loss was close to 1 per 1,000, whatever the cohort considered, quantifying the lack of improvement of graft losses in the long term since the early 1970s. It was also possible to evaluate the composition of the risk and to explore the respective influence of graft failure and of patient death.