The impact of the UNOS mandatory sharing policy on recipients of the black and white races--experience at a single renal transplant center

Racial Disparities in Renal Allograft Survival: A Public Health Issue?

BACKGROUND

Racial disparities in renal transplantation outcomes have been documented with inferior allograft survival among African Americans compared with non-African Americans. These differences have been attributed to a variety of factors, including immunologic hyperresponsiveness, socioeconomic status, compliance, HLA matching, and access to care. The purpose of this study was to examine both immunologic and nonimmunologic risk factors for allograft loss with a goal of defining targeted strategies to improve outcomes among African Americans.

STUDY DESIGN

We retrospectively analyzed all primary deceased-donor adult renal transplants (n = 2,453) at our center between May 1987 and December 2004. Analysis included the impact of recipient and donor characteristics, HLA typing, and immunosuppressive regimen on graft outcomes. Data were analyzed using standard Kaplan-Meier actuarial techniques and were explored with nonparametric and parametric methods. Multivariable analyses in the hazard-function domain were done to identify specific risk factors associated with graft loss.

RESULTS

The 1-year allograft survival in recipients improved substantially throughout the study period, and 3-year allograft survival also improved. Risk factor analyses are shown by type of allograft and according to specific time periods. Risk of immunologic graft loss (acute rejection) was most prominent during the early phase. During late-phase, immunologic risk persists (chronic rejection), but recurrent disease, graft quality, and recipient's comorbidities have an increasingly greater role.

CONCLUSIONS

Advances in immunosuppression regimens have contributed to allograft survival in both early and late (constant) phases throughout all eras, but improvement in longterm outcomes for African Americans continues to lag behind non-African Americans. The disparity in renal allograft loss between African Americans and non-African Americans over time indicates that beyond immunologic risk, the impact of nonimmunologic variables, such as time on dialysis pretransplantation, diabetes, and access to medical care, can be key issues.

Disparities in outcome for black patients after pediatric heart transplantation

OBJECTIVE

To examine the relationship of black race to graft survival after heart transplantation in children.

STUDY DESIGN

United Network for Organ Sharing records of heart transplantation for subjects <18 years of age from 1987 to 2004 were reviewed. Analysis was performed using proportional hazards regression controlling for other potential risk factors.

RESULTS

Of the 4227 pediatric heart transplant recipients, 717 (17%) were black. The 1-year graft survival rate did not differ among groups; however, the 5-year graft survival rate was significantly lower for black recipients, 51% versus 69%, P < .001. The median graft survival for black recipients was 5.3 years as compared with 11.0 years for other recipients. Black recipients had a greater number of human leukocyte antigen mismatches, lower median household income, and a greater percentage with Medicaid as primary insurance, P < .001, P < .001, and P < .001. After adjusting for economic disparities, black race remained significantly associated with graft failure, odds ratio = 1.67 (95% CI 1.47 to 1.87), P < .001.

CONCLUSIONS

Median graft survival after pediatric heart transplantation for black recipients is less than half that of other racial groups. These differences do not appear to be related primarily to economic disparities.

Health disparities in transplantation: focus on the complexity and challenge of renal transplantation in African Americans

The field of renal transplantation has grown exponentially as a result of a greater understanding of the immune system and the advent of numerous immunosuppressive agents. Although African Americans and whites have benefited from these advances, equivalent long-term success eludes African Americans who are disadvantaged in gaining access to renal transplantation. This review summarizes the obstacles for African Americans to end-stage renal disease(ESRD) care, focusing on transplantation. Factors that predispose African Americans for ESRD, impede this ethnic group from timely transplantation, and negatively influence graft survival are examined. Possible solutions to these persistent problems are offered.

African Americans and renal transplantation: disproportionate need, limited access, and impaired outcomes

BACKGROUND

Renal transplantation is the therapy of choice for patients with end-stage renal disease (ESRD). However, African Americans' (AA) access to this modality is not commensurate with that of other races. This imbalance, coupled with AA disproportionately representing those with ESRD, has kept AA disadvantaged compared with other races, especially whites.

METHODS

We reviewed published reports that examined the connection between race and the incidence of chronic renal failure, access to optimal therapy, and outcomes of renal transplantation.

RESULTS

The incidence of ESRD in AA is 4 times greater than in whites, but AA remain less likely than whites to be referred for or undergo renal transplantation. Also, AA are at greater risk than whites to experience premature graft failure.

CONCLUSIONS

ESRD management has improved dramatically with the advent of successful renal transplantation. However, AA remain significantly disadvantaged in both access and outcomes compared with whites. Further evaluation of underlying causes and development of specific remedies is warranted.

The impact of HLA mismatches on the survival of first cadaveric kidney transplants

BACKGROUND

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.

METHODS

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.

RESULTS

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.

CONCLUSIONS

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.

OKT4 epitope correlates with renal allograft survival in African Americans

Flow cytometry was used to type the distribution of OKT4 and OKT4A epitopes in a population of African American renal allograft recipients. The prevalence of the OKT4A epitope is more common than previously described and is associated with increased graft survival.