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HLA typing and the time a patient has spent on the waiting list are the primary criteria used to allocate cadaveric kidneys for transplantation in the United States. Candidates with no HLA-A, B, and DR mismatches are given top priority, followed by candidates with the fewest mismatches at the HLA-B and DR loci; this policy contributes to a higher transplantation rate among whites than nonwhites. We hypothesized that changing this allocation policy would affect graft survival and the racial balance among transplant recipients.We estimated the relative rates of kidney transplantation according to race resulting from the current allocation policy and racial differences in HLA antigen profiles, using a Cox model for the time from placement on the waiting list to transplantation. Another model, also adjusted for HLA-B and DR antigen profiles, estimated the relative rates of kidney transplantation that would result if the distribution of these antigen profiles were identical among the racial and ethnic groups. We also investigated the effect of HLA matching on the risk of graft failure, using a Cox model for the time from the first transplantation to graft failure. The results of the two analyses were used to estimate the change in the racial balance of transplantation and graft-failure rates that would result from the elimination of HLA-B matching or HLA-B and DR matching as a means of assigning priority.Eliminating the HLA-B matching as a priority while maintaining HLA-DR matching as a priority would decrease the number of transplantations among whites by 4.0 percent (166 fewer transplantations over a one-year period), whereas it would increase the number among nonwhites by 6.3 percent and increase the rate of graft loss by 2.0 percent.Removing HLA-B matching as a priority for the allocation of cadaveric kidneys could reduce the existing racial imbalance by increasing the number of transplantations among nonwhites, with only a small increase in the rate of graft loss.

Background The extent to which renal allotransplantation — as compared with long-term dialysis — improves survival among patients with end-stage renal disease is controversial, because those selected for transplantation may have a lower base-line risk of death. Methods In an attempt to distinguish the effects of patient selection from those of transplantation itself, we conducted a longitudinal study of mortality in 228,552 patients who were receiving long-term dialysis for end-stage renal disease. Of these patients, 46,164 were placed on a waiting list for transplantation, 23,275 of whom received a first cadaveric transplant between 1991 and 1997. The relative risk of death and survival were assessed with time-dependent nonproportional-hazards analysis, with adjustment for age, race, sex, cause of end-stage renal disease, geographic region, time from first treatment for end-stage renal disease to placement on the waiting list, and year of initial placement on the list. Results Among the various subgroups...

The benefits of HLA-A, B, and DR matching of cadaveric kidney grafts and recipients remain controversial when viewed from the perspective of social equity and graft survival.We estimated graft survival using proportional-hazards techniques, adjusting for patient and donor characteristics, for a series of 30,564 Medicare patients receiving a first cadaveric kidney transplant between 1984 and 1990. The effects of minimal achievable HLA mismatches and maximal matching on graft survival were estimated by simulated allocation of a sample of organs to a sample of 20,000 candidates for transplantation.The adjusted one-year graft survival was 84.3 percent for grafts with no mismatches and 77.0 percent for grafts with four mismatches. National rationing of donor organs to achieve minimal mismatching and maximal matching could potentially decrease the average number of HLA mismatches from 3.6 to 1.2, with a corresponding increase in the number of matches. As a consequence, projected five-year graft survival could potentially increase from 58.5 percent to 62.9 percent. This would be associated with a decrease in the proportion of kidneys allocated to black recipients from 22.2 to 15.0 percent.Under ideal circumstances, a policy of maximal matching of cadaveric renal transplants would increase five-year graft survival by a comparatively small 4.4 percentage points, but the actual benefit is likely to be smaller.