Long Term Outcomes of Kidney Transplant: Characteristics of Recipients with 20 or More Years of Graft Survival

Abstract

Objective: Kidney transplant survival in the first year after transplantation has significantly improved, although long-term results are less encouraging. In recent years the pressure on the scientific community on the need to refine methods to discover the possible factors that can predict graft survival after 10, 20 years or more after transplantation is increased. Few previous studies have evaluated patient and laboratory characteristics associated with optimal long-term graft survival. The objective of this study was to identify possible factors associated with the survival of the transplanted kidney in the very long term. Methods: We retrospectively studied adults who had received first-time, single kidney transplants between 1967 and 1991 at S. Orsola Hospital in Kidney Transplant Centre in Bologna. We compared the clinical, immunological, and laboratory profile of patients whose grafts were still functioning ≥ 20 years after kidney transplantation to those whose transplants survived <20 years. Results: We identified 111 patients (24.5%) who received transplants with a functioning graft for 20 or more years after transplantation. Female gender, living donor, younger donor age, shorter delayed graft function duration (DGF), lower one-year creatinine and higher one-year eGFR predicted ≥ 20-year functional graft survival in the univariate analyses. In the multivariate analysis, only female gender, shorter DGF duration and 1-year creatinine and eGFR remained as significant predictors of graft survival ≥ 20 years. Conclusions: To our knowledge, this is the first report of 20-year graft survival being associated with one-year renal function. Accordingly, efforts should be targeted to preserving graft function in the first year after kidney transplantation. In addition we have identified a population of long-term kidney transplants survivors who will be the subject of further studies in order to clarify mechanism of immunological tolerance to transplant.