SIGNIFICANCE OF THE DONOR AGE EFFECT ON KIDNEY-TRANSPLANTS

The shortage of cadaveric donor kidneys for transplantation has forced a re-evaluation of the limits on donor age acceptability. However, as more kidneys from older donors have been transplanted, a significantl y lower graft survival has been noted among their recipients. The impa ct of utilizing older donor kidneys and the relative importance of don or age with respect to other factors has not been clarified. A total o f 43 172 cadaver donor transplants reported to the UNOS Scientific Ren al Transplant Registry between 1987 and 1995 were the subjects of this study. Cox regression analysis was utilized to assess the joint effec ts on graft survival of donor age and HLA mismatch, recipient sex, rac e, age, original disease, donor death cause, cold ischemia time, and t ransplant year. Increased first day anuria, dialysis requirement, and discharge serum creatinine were noted with increasing donor age. Moreo ver, long-term graft and patient survival diminished as donor age incr eased. The 5-yr graft survival of zero HLA-A,B,DR mismatched kidneys f ell steadily from 81% when the donor was aged 21-30 to 39% when the do nor was over age 60. The reported causes of kidney transplant failure were remarkably similar for old and young donors. The best transplant results were obtained with zero HLA-A,B,DR mismatched transplants from young donors and the worst with older donor kidneys, regardless of HL A compatibility. We calculated that up to 21% of kidney failures resul ted from insufficient renal mass due to age and were incorrectly attri buted to chronic rejection.