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

Outcome predictors in African-American deceased-donor renal allograft recipients

The relative importance of donor and recipient risk factors in predicting outcomes in African-American (AA) renal allograft recipients receiving contemporary immunosuppression, including early steroid withdrawal, has not been previously examined. We assessed the impact of 21 risk factors on five primary outcomes in 132 deceased-donor AA renal allograft recipients transplanted from July 2001 to August 2006 with follow-up 6-67 (mean 35 +/- 17) months by univariate and multivariate analysis. Thymoglobulin or basiliximab was given for induction, and mycophenolate mofetil with either tacrolimus or sirolimus (SRL) +/- prednisone for maintenance. Non-compliance accounted for 26% of graft loss (GL) and 19% of acute rejection (AR) episodes, and was more prevalent in patients who were HCV+ and those on prednisone. Delayed graft function remained a significant predictor of GL, but not via increased AR, and donor ethnicity emerged as an important predictor of patient death. De novo use of SRL resulted in increased AR, and only increased recipient age significantly predicted new-onset diabetes mellitus. Our preliminary results suggest the need for improvements in patient education, pre-transplant psychosocial assessment, and late post-transplant psychosocial support and can be utilized to help guide donor/recipient selection and tailor immunosuppressive management to optimize outcomes in this challenging group of patients.

Racial disparity trends for graft failure in the US pediatric kidney transplant population, 1980-2004

Graft survival among adult African American kidney transplant patients remains low compared to whites, but little information is available for children and adolescents. We examined trends in graft failure among US incident primary kidney transplant patients aged <19 years (n = 13 692), 1980-2004. Trends in 1-year and 2- to 5-year graft failure (for patients whose grafts survived the first year) were analyzed in 5-year intervals. One-year graft failure declined 70% for white and 77% for African American patients over the 25-year period, and 1-year graft failure rates improved at a slightly higher rate for African American compared to white patients (p = 0.02). In contrast, the graft failure rates for years 2-5 declined 53% for white and only 41% for African American patients over the 25 years (p = 0.29). In fully adjusted Cox proportional hazards analysis, the rate of graft failure among African Americans was approximately 2-fold higher than for white patients over the entire study period. Graft survival has improved slightly more for African American than white pediatric patients over the past 25 years. However, graft survival for African American pediatric patients remains poor compared with white patients.

Risk factors and consequences of delayed graft function in deceased donor renal transplant patients receiving antithymocyte globulin induction

BACKGROUND

Induction rabbit antithymocyte globulin (rATG) is largely used in renal allograft recipients at risk for delayed graft function (DGF) and immunologic rejection. The purpose of our study was to characterize risk factors and outcomes associated with DGF when it occurs in recipients undergoing routine rATG induction.

METHODS

We retrospectively reviewed our experience in a predominantly high-risk population receiving modern immunosuppressive regimens.

RESULTS

Of 231 deceased-donor transplants, high-risk characteristics included African American race (68%), retransplants (12%), peak panel reactive antibody of atleast 20% (19%), expanded criteria donor kidney (15%), and cold ischemia time exceeding 24 hr (27%). DGF occurred in 29% of patients. rATG was continued to a dose of 7.3 mg/kg in DGF patients and 5 mg/kg in non-DGF patients (P<0.0001). Risk factors for DGF were recipient body mass index greater than 30 kg/m(2) (odds ratio [OR]=1.5, P=0.02), female donor/male recipient pairings (OR=1.5, P=0.033), sirolimus use (OR=1.7, P=0.003), and donor creatinine more than 1.5 mg/dL (OR=1.6, P=0.016). One-year patient survival (99% non-DGF, 91% DGF; P=0.001) and acute rejection incidence through 36 months (11% non-DGF, 22.4% DGF; P=0.025) differed between groups. DGF patients experienced a higher rejection rate during the second and third years posttransplant. Death-censored graft survival was similar throughout 36 months.

CONCLUSION

In kidney transplantation with routine rATG induction, DGF was related to size and gender, donor creatinine, and immunosuppressive protocol. Despite low first-year rejection rates, DGF was associated with inferior patient survival. Importantly, patients with DGF continued to be at risk for rejection beyond the first year. Donor and recipient selection impacts short-term outcomes, and induction alone may not confer a long-term advantage without further modification of baseline therapy.

The role of anemia management in improving outcomes for African-Americans with chronic kidney disease

Chronic kidney disease (CKD) is a serious threat to African-American public health. In this population CKD progresses to end-stage renal disease (ESRD) at quadruple the rate in Caucasians. Factors fueling progression to ESRD include diabetes and hypertension, which show high prevalences and accelerated renal damage in African- Americans, as well as possible nutritional, socioeconomic, and genetic factors. Anemia, a common and deleterious complication of CKD, is more prevalent and severe in African-American than Caucasian patients at each stage of the disease. Proactive management of diabetes, hypertension, anemia, and other complications throughout the course of CKD can prevent or delay disease progression and alleviate the burden of ESRD for the African-American community. Currently, African-Americans with CKD are less likely than Caucasian patients to receive anemia treatment before and after the onset of dialysis. Although African-Americans often require higher doses of erythropoiesis-stimulating agents, this may result from late treatment initiation, lower hemoglobin levels, or the presence of comorbidities such as diabetes and inflammation, although racial differences in response cannot be excluded. This review explores racial-specific challenges and potential solutions in renal anemia management to improve outcomes in African-American patients.

Ethnically mismatched cord blood transplants in African Americans: the Saint Louis Cord Blood Bank experience

BACKGROUND

For ethnic minority patients where a suitably matched BM or peripheral blood donor is frequently unavailable, cord blood offers an opportunity for hematopoietic stem cell transplantation. Focused recruitment of ethnic minorities for cord blood donation has been proposed as the preferred strategy to improve access for minority recipients to cord blood for transplantation. The aim of this study was to evaluate cord blood characteristics for Caucasian and African American donors and the success of ethnically mismatched UC blood transplantation in African American recipients.

METHODS

Retrospective data analysis was performed comparing the characteristics of 556 cord blood units from African American and Caucasian donors. The outcomes of 18 African American ethnically mismatched transplant recipients were compared with a paired sample of 18 ethnically matched Caucasian recipients.

RESULTS

The fraction of collected units meeting acceptability criteria from African Americans was significantly lower compared with Caucasians (P = <0.0001). Additionally, African Americans had a significantly lower post-processing total nucleated cell count (TNC) compared with Caucasians (P=0.007) but there were no other significant differences in conventionally measured product characteristics. In the transplant analysis, there was no difference in overall survival at 1 year (P=0.85) or time to neutrophil engraftment (P=0.92) between the two patient populations.

DISCUSSION

At comparable levels of TNC dose and HLA matching, the use of ethnically mismatched UC blood units as a source for allogeneic unrelated transplant can result in successful transplant outcomes for African American patients.

Racial differences in graft survival: a report from the North American Pediatric Renal Trials and Collaborative Studies (NAPRTCS)

Multiple studies have documented racial differences in graft survival in kidney transplant recipients. Although several studies in adult kidney transplant recipients have evaluated risk factors that might predispose to these differences, studies in pediatric patients are lacking. This study retrospectively analyzed data from the North American Pediatric Renal Trials and Collaborative Studies (NAPRTCS) to identify racial differences in kidney transplant outcomes and evaluate factors that might contribute to those differences. The study was restricted to the first NAPRTCS registry-reported kidney transplant for pediatric patients (age < or =21 yr) whose race was reported as either black or white. Univariate graft survival analyses were performed using the log rank statistic. Relative hazard rates for the effect of race on graft failure were determined using proportional hazards models. Multivariate analyses were restricted to patients with >30 d of graft survival and were adjusted for initial diagnosis, donor source, presence of delayed graft function, era of transplantation, estimated GFR at 30 d after transplantation, and number of days hospitalized in the first month after transplantation. Graft survival was significantly lower in black transplant recipients at 3 yr (70.9 versus 83.3%) and 5 yr (59.9 versus 77.7%). After controlling for confounding factors, black recipients continued to have a higher risk for graft failure than white recipients (adjusted hazard rate 1.65; 95% confidence interval 1.46 to 1.86). Significant racial differences in kidney transplant outcomes exist among pediatric patients even after controlling for confounding factors.

The Path Not Taken: Social and Cultural Barriers to Thoracic Transplantation

Religious beliefs, misperceptions, and distrust of the health care system have been cited as barriers to organ donation or transplantation in minorities. Improved training of hospital staff on donation protocols has been demonstrated to increase consent rates for or-gan donation. Increased interaction of minorities with ethnically appropriate transplant candidates, recipients, and donation or procurement personnel has a positive effect on donor rates. Programs using such practices must be expanded to overcome significant barriers to the transplantation of solid organs. Research into additional ways to improve acceptance of organ transplantation by minorities is needed to increase participation rates.