Increased risk for death and transplant failure after transplantation with kidneys from Expanded Criteria Donors in the Netherlands
F. van Ittersum, M. van Diepen, A. Hemke, F.W. Dekker, A.J. Hoitsma
Moderator(s): J. Ringers en T.P.J. Bezema
Location(s): Kleine Foyer
Category:
Introduction. Since the number of patients on the kidney waiting list started to increase from about 1980, criteria for organ donors have been expanded. UNOS classifies donors as Expanded Criteria Donors (ECD) in case of 1) age ≥ 60 years, or 2) age 50 to 60 years together with a history of hypertension, or a creatinine level over 132 µmol/l or CVA as death cause. Survival of ECD donor kidneys and their recipients has not been evaluated extensively in the Netherlands. Therefore, we compared outcome of ECD and non-ECD kidney transplantations in a Dutch transplant cohort, stratifying by age and diabetes.
Methods. All baseline and follow-up data of postmortal kidney transplantations between 1995 and 2005 in the Netherlands were derived from the Nederlandse Orgaan Transplantatie Registratie (NOTR). We included all first kidney transplants in recipients ≥ 18 years. Relative risks were analyzed by calculating hazard ratios (HR [95% CI]) using Cox proportional hazard models with ECD as determinant. We adjusted for confounding factors in two steps: 1) for HLA sharing, cold ischaemia time, donation after cardiac death (versus donation after brain death), and year of transplant; 2) for the confounders in step 1) and recipient characteristics such as age, gender previous dialysis duration, and PRA. Absolute risk differences were analyzed by calculating incidence density differences (IDD).
Results. We identified 3062 kidney transplantations (mean recipient age 49.0 (SD 12.8) years; 59% male; 955 ECD). In general, ECD was positively associated with graft failure including death (adjusted HR 1.54 [1.38 – 1.71]; crude IDD 37.8 [29.2 – 46.5]/1000 person-years). The adjusted HR tended to be lower in the recipients ≥ 60 years of age (1.26 [1.04 – 1.53] versus 1.68 [1.29 – 2.18] in recipients < 40 years; p between these groups 0.09). IDDs (unadjusted) were similar in the these age groups. In diabetic patients, the HR for graft failure including death was even higher: 2.10 [1.37 – 3.22] versus 1.52 [1.36 – 1.70] in the non-diabetic group, but not statistically significant (p = 0.2).
Conclusion. ECD kidney grafts have a poorer prognosis than non-ECD grafts. The adjusted relative risk for transplant failure and death is higher in younger recipients and diabetic patients. Further studies and ethical discussions should reveal whether donor kidney quality, characterized by ECD or more sophisticated classification systems, should influence the allocation to specific subgroups.