The UNOS scientific renal transplant registry. United Network for Organ Sharing.Clin Transpl. 1995CT
Overall one-, 5-, and projected 10-year graft survival rates were 81%, 58% and 39%, respectively for 51,442 cadaveric kidney transplants performed at 251 U.S. transplant centers from October 1987-December 1994. The comparable results for recipients of living donor kidneys were significantly higher, 91%, 75%, and 60% (p<0.001). One-year first cadaver graft survival rates improved from 77% for transplants performed in 1987-1988 to 84% for transplants performed in 1991-1992 (p<0.001). Recipients of second cadaveric transplants in 1987-1988 had a 69% one-year graft survival rate compared with 81% for those transplanted after 1990 (p<0.001). Graft survival rates have been stable since 1991. The percentage of broadly sensitized first transplant recipients decreased from 13% before 1991 to 7% after, and the one-year graft survival rates increased by 4-6% for both sensitized and nonsensitized recipients between the 2 periods (p<0.001). Among retransplanted patients, the percent of broadly sensitized recipients fell from 40-33% over the same periods (p<0.01). One-year graft survival rates increased by 7-8% for sensitized and nonsensitized patients (p<0.001). One-year graft survival rates improved from 74-83% for Blacks (p<0.001) and from 78-85% for non-Blacks (p<0.001) transplanted for the first time when comparing transplants performed in 1987-88 with those performed in 1993-94. The cause of donor death had a significant effect on graft survival. The 5-year graft survival rate was 61% for 28,923 recipients of trauma donor kidneys compared with 54% for 16,956 transplants from CVA donors (p<0.001). Kidneys from CVA donors increased from 28% of all cadaveric kidneys in 1988 to 38% in 1994. The donor's age was a more important determinant of long-term survival, however, and correlated strongly with the cause of donor death. Only 16% of CVA donors were reportedly age 30 or less, compared with 75% of trauma donors. First cadaver graft survival decreased by approximately 2% for each 12 hours of cold ischemia time. Although there was a significant increase in the incidence of delayed graft function from 19% when the CIT was less than 12 hours to 35% when the CIT was more than 36 hours, there was no significant long-term effect of cold ischemia time. The recent change in UNOS policy to share zero-HLA mismatched kidneys resulted in a 2-fold increase (from 8%-16%) in the number of HLA-matched transplants performed during the first 6 months following the change. The percentage of Blacks who have received matched kidneys following this change has increased from less than 2% to more than 5%, a 3-fold increase. The 163 Blacks who received an HLA-matched kidney prior to 1995 had a 65% 4-year graft survival rate compared with 53% for mismatched Blacks (p<0.001). The incidence of early rejections was also reduced by 25% among matched recipients and the graft half-life was 8 years compared with 5 years for mismatched Blacks. About 25% of HLA-matched kidneys were transplanted to ABO compatible but not identical recipients. Although the effect of the policy allowing compatible transplants did not result in a large number of type O kidneys transplanted to non-O recipients when only 8% of kidneys were shared, the recent change in allocation policy may be detrimental to type O waiting patients.