Validation of the KDRI in Korean Deceased Donor Kidney Transplantation

Abstract

Background: The United Network for Organ Sharing developed the continuous kidney donor risk index (KDRI) for measurement of the spectrum of risk associated with the various factors known to influence graft failure. This study was conducted in order to validate the KDRI in assessment of deceased donor kidney in Koreans. Methods: Patients (n=404) who underwent kidney transplants performed at five transplantation centers from 2000 to 2010 were studied retrospectively. The distribution of the KDRI of donor kidneys was calculated and the distribution of kidney donors by standard criteria donor (SCD)/expanded criteria donor (ECD) and KDRI was compared. The KDRI were divided into five groups: ＜0.8, 0.8∼1.0, 1.0∼1.2, 1.2∼1.4, and ≥1.4. Graft function and graft survival among KDRI groups were analyzed. Results: The mean KDRI was 1.01 (range, 0.55∼1.88). More than 90% of donors had KDRI ＜1.4. The distribution of kidneys by KDRI groups was 22.8%, 32.7%, 27.5%, 9.9%, and 7.2%, respectively. Among kidneys with KDRI ＜0.8, 10.5% were ECD, whereas all of the kidneys with KDRI ≥1.4 were ECD. The estimated GFR at one-year in the KDRI groups was 72.2, 65.8, 63.2, 69.1, and 47.1 mg/dL, respectively. Graft function was significantly lower in those with KDRI ≥1.4 (P＜0.001). Five-year graft survival in the KDRI groups was 91.6%, 92.2%, 91.3%, 94.1%, and 56.4%, respectively. Graft survival was also significantly lower in those with KDRI ≥1.4 (P=0.001). Conclusions: The KDRI is a useful tool for estimation of posttransplant outcomes in the Korean population. The KDRI can be used by physicians as an additional assessment tool to assist in the decision making process regarding donor organ selection.