Renal transplantation in black Americans

Influence of recipient race on the outcome of simultaneous pancreas and kidney transplantation

Racial differences on the outcome of simultaneous pancreas and kidney (SPK) transplantation have not been well studied. We compared mortality and graft survival of African Americans (AA) recipients to other racial/ethnic groups (non-AA) using the national data. We studied a total of 6585 adult SPK transplants performed in the United States between January 1, 2000 and December 31, 2007. We performed multivariate logistic regression analyses to determine risk factors associated with early graft failure and immune-mediated late graft loss. We used conditional Kaplan-Meier survival and multivariate Cox regression analyses to estimate late death-censored kidney and pancreas graft failure and death between the groups. Although there was no racial disparity in the first 90 days, AA patients had 38% and 47% higher risk for late death-censored kidney and pancreas graft failure, respectively (p = 0.006 and 0.001). AA patients were twice more likely to lose the kidney and pancreas graft due to rejection (OR 2.31 and 1.86, p = 0.002 and 0.008, respectively). Bladder pancreas drainage was associated with inferior patient survival (HR 1.42, 95% CI 1.15, 1.75, p = 0.001). In the era of modern immunosuppression, AA SPK transplant patients continue to have inferior graft outcome. Additional studies to explore the mechanisms of such racial disparity are warranted.

Prostate cancer treatment patterns among racial/ethnic groups in Florida

BACKGROUND

Prostate cancer is the second leading cause of cancer death among men in the United States. Blacks have the highest incidence and mortality rates. Treatment differences have been observed between black and white men. Brachy monotherapy (BMT) has become popular for localized prostate cancer because of its convenience, being the least invasive, and resulting in better quality of life during and after treatment. No studies have specifically examined BMT in treating localized prostate cancer by race/ethnicity.

OBJECTIVES

We sought to (1) describe treatment patterns among men with localized prostate cancer, (2) identify factors affecting the use of BMT, and (3) examine if there was any difference in BMT use by race and ethnicity.

METHODS

Florida cancer incidence data of 1994-2003 were used to extract information on men diagnosed with localized prostate cancer along with their demographics, primary payer at diagnosis, tumor stage and treatments. Logistic regression was performed to assess the likelihood of receiving BMT.

RESULTS

The study found that surgery and radiation were the 2 major single treatments for localized prostate cancer. The percent of patients receiving BMT treatment increased from 1994 through 2003. Men with the following characteristics were more likely to receive BMT than their counterparts: Non-Hispanic white, older, married, Medicare beneficiaries and military personnel, with well-differentiated tumor, and receiving treatment in facilities with high practice volume and/or located in urban counties.

CONCLUSION

There were racial/ethnic differences in localized prostate cancer treatment. Possible reasons for the differences require further research.

Racial variation in medical outcomes among living kidney donors

BACKGROUND

Data regarding health outcomes among living kidney donors are lacking, especially among nonwhite persons.

METHODS

We linked identifiers from the Organ Procurement and Transplantation Network (OPTN) with administrative data of a private U.S. health insurer and performed a retrospective study of 4650 persons who had been living kidney donors from October 1987 through July 2007 and who had post-donation nephrectomy benefits with this insurer at some point from 2000 through 2007. We ascertained post-nephrectomy medical diagnoses and conditions requiring medical treatment from billing claims. Cox regression analyses with left and right censoring to account for observed periods of insurance benefits were used to estimate absolute prevalence and prevalence ratios for diagnoses after nephrectomy. We then compared prevalence patterns with those in the 2005-2006 National Health and Nutrition Examination Survey (NHANES) for the general population.

RESULTS

Among the donors, 76.3% were white, 13.1% black, 8.2% Hispanic, and 2.4% another race or ethnic group. The median time from donation to the end of insurance benefits was 7.7 years. After kidney donation, black donors, as compared with white donors, had an increased risk of hypertension (adjusted hazard ratio, 1.52; 95% confidence interval [CI], 1.23 to 1.88), diabetes mellitus requiring drug therapy (adjusted hazard ratio, 2.31; 95% CI, 1.33 to 3.98), and chronic kidney disease (adjusted hazard ratio, 2.32; 95% CI, 1.48 to 3.62); findings were similar for Hispanic donors. The absolute prevalence of diabetes among all donors did not exceed that in the general population, but the prevalence of hypertension exceeded NHANES estimates in some subgroups. End-stage renal disease was identified in less than 1% of donors but was more common among black donors than among white donors.

CONCLUSIONS

As in the general U.S. population, racial disparities in medical conditions occur among living kidney donors. Increased attention to health outcomes among demographically diverse kidney donors is needed. (Funded by the National Institute of Diabetes and Digestive and Kidney Diseases and others.)

Neighborhood poverty, racial composition and renal transplant waitlist

To date, no study has characterized the association between neighborhood poverty, racial composition and deceased donor kidney waitlist. Using the United States Renal Data System data linked to 2000 U.S. Census Data, we examined Whites (n = 152 788) and Blacks (n = 130 300) initiating dialysis between January 2000 and December 2006. Subjects' neighborhoods were divided into nine strata based on the percent of Black residents and percent poverty. Cox proportional hazards were used to determine the association between time to waitlist and neighborhood characteristics after adjusting for demographics and comorbid conditions. Individuals from poorer neighborhoods had a consistently lower likelihood of being waitlisted. This association was synergistic with neighborhood racial composition for Blacks, but not for Whites. Blacks in poor, predominantly Black neighborhoods (adjusted hazard ratio [HR] 0.57, 95% confidence intervals [CI] 0.53-0.62) were less likely to appear on transplant waitlist than those in wealthy, predominantly Black neighborhoods (HR 0.80, CI 0.67-0.96) and poor, predominantly White neighborhoods (HR 0.79, CI 0.70-0.89). All were all less likely to be waitlisted than their Black counterparts in wealthy, predominantly White or mixed neighborhoods (p < 0.05). Interventions targeted at individuals in poor and minority neighborhoods may represent an opportunity to improve equitable access to the deceased donor kidney waitlist.

Addressing racial and ethnic disparities in live donor kidney transplantation: priorities for research and intervention

One potential mechanism for reducing racial/ethnic disparities in the receipt of kidney transplants is to enhance minorities' pursuit of living donor kidney transplantation (LDKT). Pursuit of LDKT is influenced by patients' personal values, their extended social networks, the health care system, and the community at large. This review discusses research and interventions promoting LDKT, especially for minorities, including improving education for patients, donors, and providers, using LDKT kidneys more efficiently, and reducing surgical and financial barriers to transplant. Future directions to increase awareness of LDKT for more racial/ethnic minorities also are discussed including developing culturally tailored transplant education, clarifying transplant-eligibility practice guidelines, strengthening partnerships between community kidney providers and transplant centers, and conducting general media campaigns and community outreach.

Optimizing medication adherence: an ongoing opportunity to improve outcomes after kidney transplantation

Nonadherence of transplant recipients to prescribed medical regimens has been identified as a major cause of allograft failure. Although recent studies offer new insight into the clinical phenotypes of nonadherence, advances in defining risk factors and appropriate interventions have been limited because of variable definitions, inadequate clinical metrics, and the challenges associated with healthcare delivery. Significant nonadherence is estimated to occur in 22% of renal allograft recipients and may be a component of allograft loss in approximately 36% of patients. It is associated with increased incidence of rejection (acute and chronic) and, consequently, shortened renal allograft survival, requiring reinstitution of costly chronic renal replacement therapy with an incumbent effect on morbidity and mortality. The economic effect of nonadherence approaches similar magnitude. Identification of risk factors, coupled with measures that effectively address them, can have a positive effect at many levels--medically, socially, and economically. Further advances are likely to be dependent on improving interactions between patients and caregivers, broadening immunosuppressant availability, and newer therapeutics that move toward simpler regimens.

Health disparities: a primer for public health social workers

In 2001, the U.S. Department of Health and Human Services published Healthy People 2010, which identified objectives to guide health promotion and to eliminate health disparities. Since 2001, much research has been published documenting racial and ethnic disparities in healthcare. Although progress has been made in eliminating the disparities, ongoing work by public health social workers, researchers, and policy analysts is needed. This paper focuses on racial and ethnic health disparities, why they exist, where they can be found, and some of the key health/medical conditions identified by the U.S. Department of Health and Human Services to receive attention. Finally, there is a discussion of what policy, professional and community education, and research can to do to eliminate racial and ethnic disparities in healthcare.

Racial disparities in urologic health care

In the United States, disparities in health care delivery and access are apparent between different racial and ethnic groups. Minorities, including African Americans, often suffer disproportionately from disease compared to Caucasians. In the urologic arena, this is apparent in urologic cancer screening, treatment choices, and survival, as well as in the arena of chronic kidney disease, transplant allocation, and transplant outcomes. Latino men also seem to be affected more often by erectile dysfunction than Caucasian counterparts. Disparities such as these have been identified as a problem in the delivery of health care in the United States, and resources have been allocated to help allay the disparity. Through organizations such as the Cleveland Clinic Minority Men's Health Center, policy initiatives, and increased cultural awareness by physicians, steps can be made to reduce and eliminate health care disparities.

CD127(low) expression in CD4+CD25(high) T cells as immune biomarker of renal function in transplant patients

BACKGROUND

Noninvasive tests measuring cellular immunity could help predict immunologic risk and subsequent allograft dysfunction in transplant patients. CD25 is a promising marker of activation. Recent descriptions of CD127 expression as a discriminating factor between regulatory and activated T cells suggest its potential utility.

METHODS

Expression of CD127 in CD4+CD25 T cells was analyzed by flow cytometry in peripheral blood from 62 renal transplanted patients and 30 healthy controls. Forty patients presented stable graft function and 22 suffered renal failure.

RESULTS

Renal transplant patients showed higher levels of CD127(high) and a lower frequency of CD127(low) than healthy controls (0.63% vs. 0.29% [P<0.001] and 1.4% vs. 2.4% [P<0.001], respectively). However, high frequencies of not only CD127(high) but also CD127(low) showed a significant correlation with serum creatinine levels (P=0.012 and P=0.003, respectively). Allogenic stimulation in vitro increased the frequency of CD127(low) subset in a dose dependent manner. Furthermore, in patients with a high frequency of CD127(low) subset, this consisted mostly of FoxP3 negative cells, discarding their regulatory origin. Median frequency of CD127(low), but not CD127(high), cells showed significant differences between patients with stable function and with renal failure (P<0.005), with 16.7% and 53.1% of individuals above the median CD127(low) value (1.4%), respectively.

CONCLUSION

Quantification of CD127(low) subset through staining of CD4+ T cells with the combined markers CD127/CD25/CD45RO has been demonstrated to be a significant tool for monitoring the outcome course of renal transplant patients.

Racial and ethnic differences in mortality in children awaiting heart transplant in the United States

Racial differences in outcomes are well known in children after heart transplant (HT) but not in children awaiting HT. We assessed racial and ethnic differences in wait-list mortality in children <18 years old listed for primary HT in the United States during 1999-2006 using multivariable Cox models. Of 3299 listed children, 58% were listed as white, 20% as black, 16% as Hispanic, 3% as Asian and 3% were defined as 'Other'. Mortality on the wait-list was 14%, 19%, 21%, 17% and 27% for white, black, Hispanic, Asian and Other children, respectively. Black (hazard ratio [HR] 1.6, 95% confidence interval [CI] 1.3, 1.9), Hispanic (HR 1.5, CI 1.2, 1.9), Asian (HR, 2.0, CI 1.3, 3.3) and Other children (HR 2.3, CI 1.5, 3.4) were all at higher risk of wait-list death compared to white children after controlling for age, listing status, cardiac diagnosis, hemodyamic support, renal function and blood group. After adjusting additionally for medical insurance and area household income, the risk remained higher for all minorities. We conclude that minority children listed for HT have significantly higher wait-list mortality compared to white children. Socioeconomic variables appear to explain a small fraction of this increased risk.

Predictors of having a potential live donor: a prospective cohort study of kidney transplant candidates

The barriers to live donor transplantation are poorly understood. We performed a prospective cohort study of individuals undergoing renal transplant evaluation. Participants completed a questionnaire that assessed clinical characteristics as well as knowledge and beliefs about transplantation. A participant satisfied the primary outcome if anyone contacted the transplant center to be considered as a live donor for that participant. The final cohort comprised 203 transplant candidates, among whom 80 (39.4%) had a potential donor contact the center and 19 (9.4%) underwent live donor transplantation. In multivariable logistic regression, younger candidates (OR 1.65 per 10 fewer years, p < 0.01) and those with annual income >or=US$ 15 000 (OR 4.22, p = 0.03) were more likely to attract a potential live donor. Greater self-efficacy, a measure of the participant's belief in his or her ability to attract a donor, was a predictor of having a potential live donor contact the center (OR 2.73 per point, p < 0.01), while knowledge was not (p = 0.56). The lack of association between knowledge and having a potential donor suggests that more intensive education of transplant candidates will not increase live donor transplantation. On the other hand, self-efficacy may be an important target in designing interventions to help candidates find live donors.

Outcome of kidney transplantation in Canadian Aboriginal children in the province of British Columbia

Renal transplantation remains the therapy of choice for children and adolescents with ESRD. Differences in graft survival are observed in kidney transplant recipients of different race and ethnicities. Data in pediatric populations are limited and confounded by disparities in access to health care. We performed a retrospective single Canadian centre database review to determine the short- and long-term outcomes of kidney transplantation in Aboriginal children compared to non-Aboriginals. A total of 159 primary renal transplant recipients at BCCH between 1985 and 2005 were examined (15% Aboriginal). Aboriginal children had different etiologies of ESRD, and a higher percentage of females, but were similar in age at transplantation, cold ischemia time and living donation rate. Early graft outcomes such as delayed graft function, episodes of acute rejection in the first year post-transplant and estimated glomerular function rate at one yr were similar in both groups. Long-term graft survival, however, was significantly worse in the Aboriginal group, with a significantly increased rate of late rejections: 50% compared with 26.7% among non-Aboriginals (p = 0.03). In a province with uniform access to health care, significant differences in long-term graft outcome exist among Aboriginal children compared with non-Aboriginals.

Evaluating options for utility-based kidney allocation

Over the last 5 years, a number of utility-based allocation systems have been proposed in an effort to increase the life-prolonging potential of deceased donor kidneys in the United States. These have included various adaptations of age-matching and net benefit, including the Eurotransplant Senior Program, Life Years From Transplant, and several systems for avoiding extreme donor/recipient mismatch. However, utility-based allocation is complex and raises issues regarding choice of metric, appropriateness of certain factors for use in allocation, accuracy of prediction models, transparency and perception, and possible effects on donation rates. Changing the role of utility in kidney allocation will likely cause changes to efficiency, equity, predictability, autonomy, controversy, trust and live donation. In this manuscript, various allocation systems are discussed, and a framework is proposed for quantifying the goals of the transplant community and evaluating options for utility-based kidney allocation in this context.

Neighborhood poverty and racial disparities in kidney transplant waitlisting

Racial disparities persist in the United States renal transplantation process. Previous studies suggest that the distance between a patient's residence and the transplant facility may associate with disparities in transplant waitlisting. We examined this possibility in a cohort study using data for incident, adult ESRD patients (1998 to 2002) from the ESRD Network 6, which includes Georgia, North Carolina, and South Carolina. We linked data with the United Network for Organ Sharing (UNOS) transplant registry through 2005 and with the 2000 U.S. Census geographic data. Of the 35,346 subjects included in the analysis, 12% were waitlisted, 57% were black, 50% were men, 20% were impoverished, 45% had diabetes as the primary etiology of ESRD, and 73% had two or more comorbidities. The median distance from patient residence to the nearest transplant center was 48 mi. After controlling for multiple covariates, distance from patient residence to transplant center did not predict placement on the transplant waitlist. In contrast, race, neighborhood poverty, gender, age, diabetes, hypertension, body mass index, albumin, and the use of erythropoietin at dialysis initiation was associated with waitlisting. As neighborhood poverty increased, the likelihood of waitlisting decreased for blacks compared with whites in each poverty category; in the poorest neighborhoods, blacks were 57% less likely to be waitlisted than whites. This study suggests that improving the allocation of kidneys may require a focus on poor communities.

Socioeconomic position and graft failure in pediatric heart transplant recipients

BACKGROUND

Socioeconomic (SE) position may affect availability of resources, health-related behavior, and outcomes. We assessed whether patient SE position, determined for the block group of patient residence (average population 1000, smallest census unit with SE data), is associated with graft failure in pediatric heart transplant recipients.

METHODS AND RESULTS

We used the US Census 2000 database to derive a composite SE score for the block group of residence for all patients who underwent their first heart transplant at Children's Hospital Boston between 1991 and 2005 (n=135). Cox proportional hazards models were used to determine the risk of graft failure (death or retransplant) in the lowest tertile SE group (low SE group) compared with the remaining 2 of 3 patients (controls). The 2 groups were similar with respect to age, gender, diagnosis, and year of transplant. White race was less frequent in low SE group (64% versus 90%, P=0.001). Graft failure occurred in 46 transplant recipients (40 deaths, 6 retransplant). Low SE group (hazard ratio 2.4, 95% CI 1.3 to 4.3) and nonwhite race (hazard ratio 2.7, 95% CI 1.4 to 5.2) were both associated with higher risk of graft failure. In a multivariable model controlling for diagnosis and pretransplant support, race, and low SE position (hazard ratio 2.0, 95% CI 1.0 to 3.7, P=0.04) remained associated with graft failure. Low SE position group had a higher incidence rate of graft rejection and was at a higher risk of late rejection.

CONCLUSIONS

Low SE position may be an independent risk factor for graft failure in pediatric heart transplant recipients.

Framing disparities along the continuum of care from chronic kidney disease to transplantation: barriers and interventions

Research in renal transplantation continues to document scores of disparities affecting vulnerable populations at various stages along the transplantation process. Given that both biological and environmental determinants contribute significantly to variation, identifying factors underlying an unfairly biased distribution of the disease burden is crucial. Confounded definitions and gaps in understanding causal pathways impede effectiveness of interventions aimed at alleviating disparities. This article offers an operational definition of disparities in the context of a framework aimed at facilitating interventional research. Utilizing an original framework describing the entire continuum of the transplant process from diagnosis of chronic kidney disease through successful transplant, this article explores the case of racial disparities, illustrating key factors predicting and perpetuating disparities. Though gaps in current research leave us unable to identify which stages of the transplant pathway adversely affect most people, by identifying key risk factors across the continuum of care, this article highlights areas suited for targeted interventions and presents recommendations for improvement and future research.

Efficacy of induction therapy on acute rejection and graft outcomes in African American kidney transplantation

BACKGROUND

African Americans (AA) have higher rejection rates and poorer graft outcomes compared to non-AAs. Induction therapy is yet unproven in this high risk population.

METHODS

This retrospective study compared the efficacy of induction therapy [IL-2 receptor antibodies (IL2RA) or thymoglobulin] vs. no induction.

RESULTS

One hundred and seventy-five AA patients were included in this analysis. Patients were well matched for demographic and immunologic characteristics in the non-induction and IL2RA induction groups; the Thymoglobulin induction group had significantly higher risk patients. Significantly fewer episodes of acute rejection occurred at one yr in patients treated with thymoglobulin and IL2RA vs. no induction (18% vs. 47%, p = 0.003, 26% vs. 47%, p = 0.02). Three yr graft survival was significantly improved in the IL2RA group compared to the non-induction group (85% vs. 68%, p = 0.032). Despite the thymoglobulin group being at high risk, they had similar graft survival rates compared to both the IL2RA group (76% vs. 85%, p = 0.18) and the non-induction group (76% vs. 68%, p = 0.48). Multivariate analysis demonstrated that induction therapy (combining IL2RA and thymoglobulin) independently reduced the risk of both acute rejection and graft loss.

CONCLUSION

The use and type of induction therapy in AA patients significantly reduces acute rejection rates and may improve long-term graft outcomes in AA patients.

Disparities in the provision of medical care: an outcome in search of an explanation

This purpose of this paper is to review the literature on racial/ethnic disparities in the utilization and quality of care and the proposed explanations for these differences. First, the literature on racial/ethnic disparities in medical treatment is reviewed briefly with the goal of providing a sense of the range of procedures and conditions on which these disparities occur. Then, the possible role of physician/provider, patient, and health care system factors in contributing to these disparities is reviewed. Finally, suggestions for new or expanded directions for research in each of these three areas are given. The goal of the paper is to identify factors that might be particularly amenable to the type of research done by health psychologists.

Lung transplant outcomes in white and African American recipients: special focus on acute and chronic rejection

BACKGROUND

The effects of lung transplant recipient race on post-transplant outcomes have not been adequately evaluated. This cohort study seeks to determine the characteristics of African American lung transplant recipients and the effects of African American race on post-transplant outcomes, particularly acute and chronic rejection, compared with white recipients, at a single center.

METHODS

There were 485 first-time lung transplantations (431 white, 47 African American, 5 Hispanic and 2 Asian recipients) performed at the University of Pennsylvania between 1991 and 2006. All white and African American recipients were compared based on pre-transplant diagnoses and post-transplant survival. The cohort from 1998 to 2006 (239 white and 25 African American recipients) was also compared based on acute rejection score (ARS) and development of bronchiolitis obliterans syndrome (BOS).

RESULTS

Chronic obstructive pulmonary disease was the most common diagnosis leading to lung transplantation in both groups, but sarcoidosis was a much more common indication in African American recipients (white, 1%; African American, 28%; p < 0.001). Survival was similar in the two groups (white vs African American groups: 1 month, 90.0% vs 87.2%; 1 year, 74.9% vs 74.5%; 5 years, 52.3% vs 50.5%, respectively; p = 0.84). Freedom from BOS at 3 years (white, 60.3%; African American, 62.8%; p = 0.30) and ARS per biopsy (white, 0.83 +/- 0.82; African American, 0.63 +/- 0.77; p = 0.31) were similar in both groups.

CONCLUSIONS

White and African American patients seek lung transplantation for different diseases, but post-transplant outcomes were found to be similar. Larger, multi-center studies are needed to confirm these results.

Similar outcomes among black and white renal allograft recipients

Black renal transplant recipients experience shorter graft survival than white recipients, but no published data describe the graft outcomes among black Canadian recipients. Here, we analyzed data from the Canadian national renal replacement therapy registry, which included 20,243 incident dialysis patients (3% black, 97% white), 5036 of whom received a renal transplant during the study period. Black patients were significantly less likely to receive a renal transplant (deceased and living-donor combined) when compared with white patients (hazard ratio 0.59; 95% confidence interval 0.51 to 0.69; P < 0.0001). Among patients who underwent a renal transplant, there was no significant difference in the likelihood of graft failure between black and white patients, even after adjustment for comorbidities and socioeconomic status; black patients, however, had significantly lower posttransplantation mortality compared with white patients (hazard ratio 0.49; 95% confidence interval 0.28 to 0.88; P = 0.02). In conclusion, graft outcomes between black and white Canadian renal transplant patients are similar. Because this differs from the experience reported from the United States, further direct comparisons between the two populations is warranted.

Donor ethnicity influences outcomes following deceased-donor kidney transplantation in black recipients

Although the majority of deceased-donor kidneys are donated after brain death, increased recovery of kidneys donated after cardiac death could reduce the organ shortage and is now a national priority. Racial disparities in donations after brain death have been well described for renal transplantation, but it is unknown whether similar disparities occur in donations after cardiac death. In this study, outcomes of adult deceased-donor renal transplant recipients included in the United Network for Organ Sharing database (1993 through 2006) were analyzed. Among black recipients of kidneys obtained after cardiac death, those who received kidneys from black donors had better long-term graft and patient survival than those who received kidneys from white donors. In addition, compared with standard-criteria kidneys from white donors after brain death, kidneys from black donors after cardiac death conferred a 70% reduction in the risk for graft loss (adjusted hazard ratio 0.30; 95% confidence interval 0.14 to 0.65; P = 0.002) and a 59% reduction in risk for death (adjusted hazard ratio 0.41; 95% confidence interval 0.2 to 0.87; P = 0.02) among black recipients. These findings suggest that kidneys obtained from black donors after cardiac death may afford the best long-term survival for black recipients.

Thymoglobulin dose optimization for induction therapy in high risk kidney transplant recipients

BACKGROUND

Thymoglobulin (rATG) has become the agent of choice for induction therapy in high immunological risk kidney transplant recipients. However, its optimal dosing in this subgroup has not been studied.

METHODS

To evaluate the effect of total rATG dosing on graft outcomes in such patients, we conducted a retrospective cohort study of 96 adult patients who received repeat transplants (85%) or had panel reactive antibody more than 40% (19%) and were maintained on tacrolimus, mycophenolate mofetil, and steroid. Group 1 (n=33) received less than or equal to 7.5 and group 2 (n=63) received more than 7.5 mg/kg rATG. Graft and patient survival, incidence of acute rejection (AR), and 12-month serum creatinine (SCr) were examined.

RESULTS

The groups were comparable regarding demographics, donor source, retransplantation, panel reactive antibody, and human leukocyte antigen mismatch. Group 2 had more African Americans (44.4% vs. 21.2%, P=0.03). During the 25.4+/-18.0 months follow-up graft survival was 82.5% and 79.4%, respectively (P=0.54). Three in group 1 and four in group 2 died (P=0.65). The incidence of biopsy proven AR during the first 12-months did not differ between the groups (9.5% vs. 8.8%, respectively, P=0.9). SCr at 12 months was 1.6+/-0.7 in group 1 and 1.8+/-1.0 in group 2 (P=0.3). There was no independent association between rATG dose and graft survival (hazard ratio: 0.85, P=0.79, 95% CI: 0.26-2.7 for group 2 vs. 1) or 1-year SCr (regression coefficient=0.02 for ln(SCr), P=0.3; 95%CI: -0.01 to 0.6).

CONCLUSION

Our results suggest that in high risk kidney transplant recipients total rATG doses less than or equal to 7.5 mg/kg are safe and effective in achieving a low rate of AR and graft outcomes comparable to higher doses.

Promoting access to renal transplantation: the role of social support networks in completing pre-transplant evaluations

BACKGROUND

Completing pre-transplant evaluations may be a greater barrier to renal transplantation for blacks with end-stage renal disease (ESRD) than for whites.

OBJECTIVE

To determine whether social support networks facilitate completing the pre-transplant evaluation and reduce racial disparities in this aspect of care.

DESIGN, SETTING, AND PARTICIPANTS

We surveyed 742 black and white ESRD patients in four regional networks 9 months after they initiated dialysis in 1996 and 1997. Patients reported instrumental support networks (number of friends or family to help with daily activities), emotional support networks (number of friends or family available for counsel on personal problems) and dialysis center support (support from dialysis center staff and patients). The completion of pre-transplant evaluations, including preoperative risk stratification and testing, was determined by medical record reviews.

OUTCOME MEASUREMENT

Complete renal pre-transplant evaluations.

RESULTS

Compared to patients with low levels of instrumental support, those with high levels were more likely to have complete evaluations (25% versus 46%, respectively, p < .001). In adjusted analyses, high levels of instrumental support were associated with higher rates of complete evaluations among black women (p < .05), white women (p < .05), and white men (p < .05), but not black men. Among black men, but not other groups, private insurance was a significant predictor of complete evaluations.

CONCLUSIONS

Instrumental support networks may facilitate completing renal pre-transplant evaluations. Clinical interventions that supplement instrumental support should be evaluated to improve access to renal transplantation. Access to supplemental insurance may also promote complete evaluations for black patients.

Blacks as donors for transplantation: suboptimal outcomes overcome by transplantation into other minorities

BACKGROUND

In 1977, Opelz et al (Transplant Proc 9:137, 1977) introduced research that identified ethnic disparities in the relative risk of graft loss when African American donors or recipients were targeted. Current research from the Organ Procurement and Transplantation Network (OPTN) reveals a continuation of these trends. While 1-year graft survival rates for a kidney are 92.1% for Caucasians, 94.1% for Asians, and 92.9% for Latinos, the comparative rate is 88.9% for African Americans. This study extends research on health disparities by examining relative differences in graft and patient survival rates when the organ donors are African American. A number of factors have been introduced as possible determinants of disparate outcomes by ethnicity in terms of graft survival rates. This descriptive study was designed to test the hypothesis: There are no differences in the relative risks associated with graft survival rates and mortality based upon differences in the ethnicity of the donors.

MATERIALS AND METHODS

Data were obtained from the OPTN/United Network for Organ Sharing (UNOS) Registry from April 1, 1994 to December 31, 2000. A total of 118,769 transplants were analyzed, including 77,689 living and deceased donor kidney transplants, 26,124 deceased donor liver transplants, and 14,956 deceased donor heart transplants. A multivariate Cox regression model was used to determine the relative risk of graft loss and cardiac transplant mortality for different ethnicities when the organ donors were African American.

RESULTS

The study found that the relative risk of kidney graft loss was 21.3% (P < .01) higher between African American donors and Caucasian recipients than between Caucasian donors and other recipients. With liver transplants, the use of an African American donor increased the risk of graft loss by 21.5% (P < .001). When African American donors gave kidneys and livers to other African Americans, the relative risks of kidney graft loss were 50.9% higher for a kidney (P < .001) and 36.6% higher for a liver (P < .001) if both the donors and recipients were African American. The relative risk of mortality was 51.3% higher (P < .001) when African American hearts were transplanted into other African Americans. No significant differences existed in terms of the relative risk of cardiac mortality (P < .29) when African American hearts were transplanted into Caucasian recipients. When African American donors provided kidneys and livers to Latinos and Asians, the relative risk of graft loss fell below the rates for Caucasian donors and recipients. However, the differences were not statistically significant.

CONCLUSIONS

Our data have identified a pressing need to conduct clinical and prospective research that can isolate the causes of these suboptimal outcomes. This is particularly important since the number of African American organ donors has escalated as a result of recent health outreach and education efforts.

Impact of activated vitamin D and race on survival among hemodialysis patients

Contrary to most examples of disparities in health outcomes, black patients have improved survival compared with white patients after initiating hemodialysis. Understanding potential explanations for this observation may have important clinical implications for minorities in general. This study tested the hypothesis that greater use of activated vitamin D therapy accounts for the survival advantage observed in black and Hispanic patients on hemodialysis. In a prospective cohort of non-Hispanic white (n = 5110), Hispanic white (n = 979), and black (n = 3214) incident hemodialysis patients, higher parathyroid hormone levels at baseline were the primary determinant of prescribing activated vitamin D therapy. Median parathyroid hormone was highest among black patients, who were most likely to receive activated vitamin D and at the highest dosage. One-year mortality was lower in black and Hispanic patients compared with white patients (16 and 16 versus 23%; P < 0.01), but there was significant interaction between race and ethnicity, activated vitamin D therapy, and survival. In multivariable analyses of patients treated with activated vitamin D, black patients had 16% lower mortality compared with white patients, but the difference was lost when adjusted for vitamin D dosage. In contrast, untreated black patients had 35% higher mortality compared with untreated white patients, an association that persisted in several sensitivity analyses. In conclusion, therapy with activated vitamin D may be one potential explanation for the racial differences in survival among hemodialysis patients. Further studies should determine whether treatment differences based on biologic differences contribute to disparities in other conditions.

A randomized trial of a home-based educational approach to increase live donor kidney transplantation: effects in blacks and whites

BACKGROUND

Blacks are disproportionately affected by chronic kidney disease, but are far less likely to undergo live donor kidney transplantation (LDKT) than whites. We assessed the differential effectiveness in blacks and whites of a home-based (HB) LDKT educational approach.

STUDY DESIGN

A planned secondary analysis of a previously published randomized trial.

SETTING & PARTICIPANTS

132 patients (60 black, 72 white) approved for kidney transplantation at 1 kidney transplant center in the southeastern United States.

INTERVENTION

Assignment to receive either standard clinic-based (CB) transplant education (n = 69) or CB plus an HB (CB + HB) LDKT education program (n = 63). The HB education program was culturally sensitive for blacks, including using a minority health educator, brochures that highlight minority transplant recipients and donors, and discussion of race-specific outcome data.

OUTCOMES

Primary outcomes were proportions of patients with live donor inquiries, evaluations, and transplants 1 year after study participation.

MEASUREMENTS

Medical record and questionnaire data.

RESULTS

69 patients were assigned to the CB group, and 63 to the CB + HB group. After 1 year, there were 96 living donor inquiries (72.7%), 62 living donor evaluations (47.0%), and 54 LDKTs (40.9%). Patients assigned to the CB + HB group were more likely to have had living donor inquiries (odds ratio [OR], 1.7; confidence interval [CI], 1.2 to 3.0), a living donor evaluated (OR, 2.7; CI, 1.4 to 5.4), and LDKT (OR, 3.0; CI, 1.5 to 5.9). The effect was greater in blacks than whites for living donor evaluations and LDKT, but not for living donor inquiries (treatment-by-race interaction, P < 0.001, P < 0.001, and P = 0.8, respectively). Blacks in the CB + HB group were more likely to have had at least 1 living donor inquiry (51.7% versus 77.4%), at least 1 living donor evaluated (17.2% versus 48.4%), and LDKT (13.8% versus 45.2%) than those in the CB group. By comparison, whites in the CB + HB group were more likely to have had at least 1 living donor inquiry (72.5% versus 87.5%), at least 1 living donor evaluated (47.5% versus 71.9%), and LDKT (42.5% versus 59.4%) than those in the CB group.

LIMITATIONS

Single-center study with greater dropout rate in the CB + HB group.

CONCLUSIONS

These results suggest that a culturally sensitive LDKT education program that reaches out to blacks and their social support network can overcome some barriers to LDKT in this population.

Intermediate-term outcomes with early steroid withdrawal in African-American renal transplant recipients undergoing surveillance biopsy

BACKGROUND

There is a paucity of data regarding the use of early corticosteroid withdrawal (ESW) in African-American renal allograft recipients, and very few reports with >or=1 year follow-up in all patients.

METHODS

We examined the outcomes of 57 African-American renal allograft recipients with minimum follow-up 12 months who did not receive maintenance steroids after day 4 posttransplant. All patients received thymoglobulin induction, mycophenolate mofetil, and initial tacrolimus (n = 48) or sirolimus (n = 9).

RESULTS

Patient and graft survival were 98% and 96% at 1 year, and 95% and 89% over the entire follow-up period (mean, 23 +/- 8 months). Incidence of acute rejection and cytomegalovirus infection were 18% and 7%, respectively, with mean serum creatinine 1.6 +/- 0.5 and 1.7 +/- 0.9 mg/dL at 6 and 12 months. Of patients with functioning grafts, 84% remained steroid free at 1 year, of which 11 (24%) were also calcineurin inhibitor free. Twenty-seven patients underwent surveillance biopsy at 1 month and 28 at 12 months, with 15 surveyed at both time points. There were significant increases in only 2 of the 6 1997 Banff chronic allograft nephropathy (CAN) category scores in this subgroup, with all mean values remaining <1 (mild in severity) at 1 year. Overall, from 82% to 96% of the 12-month scores were <or=1 in all categories for 28 patients; only 3 patients (11%) had interstitial fibrosis and tubular atrophy scores at least moderate in severity. We did not observe any cases of subclinical acute rejection.

CONCLUSIONS

Our findings suggest that ESW in African-American renal allograft recipients with multiple high-risk factors can produce excellent intermediate-term antirejection and graft functional outcomes with minimal development of CAN at 12 months. Our results will need to be verified in larger numbers of patients with longer follow-up.

Living Kidney Donors Requiring Transplantation: Focus on African Americans

Risks of kidney donation include a poorly characterized risk of late kidney failure. We hypothesized that African Americans (AA) kidney donors were at greater risk for kidney failure. The United Network for Organ Sharing/Organ Procurement Transplantation Network database was searched for patients who previously donated a kidney and were subsequently placed on the kidney transplant waiting list. We then compared the race of donors listed for kidney transplant to the race of all living donors during the same time period. Between 1993 and 2005, 8889 donors (14.3%) were AA and 42,419 (68.1%) were Caucasian. During this same time period, 102 previous kidney donors developed kidney failure and were listed for kidney transplantation. Although AAs comprised 14.3% of all living kidney donors, they constituted 44% of donors reaching the waiting list (P<0.001). These data provide indirect evidence that the risk of kidney failure may be exaggerated in AA donors.

Corticosteroid withdrawal in kidney transplantation: the present status

Corticosteroids (CS) have played a vital role in organ transplantation, both for prevention and treatment of allograft rejection. However, the use of CS is associated with a wide range of adverse effects. With advances in immunosuppressive drug therapy, attempts have been made to minimize the use of CS to avoid or alleviate their side effects. Withdrawal of CS months after transplantation has transitioned to days. In low to intermediate risk renal allograft recipients, use of induction therapy and modern maintenance drug combinations allows safe withdrawal of CS within the first week of transplantation. In other groups, existing potent maintenance agents permit tapering of CS to low doses over the first few months. Withdrawal of these small doses may not add to the benefits.

Perceived transparency and fairness of the organ allocation system and willingness to donate organs: a national study

The influence of perceptions of organ allocation on willingness to donate organs is unclear. We performed a national study assessing the relation of public perceptions of organ allocation to willingness to donate organs, and we assessed the contribution of beliefs regarding discrimination in health care to observed associations. Among 845 participants, a majority (65%) reported that they less than "mostly" understand allocation, and most (71%) reported that they believe allocation is "unfair" or are "unsure" of its fairness. Participants reporting less understanding were less willing to donate (56%) than persons reporting greater understanding (67%) (p < 0.01). Participants believing allocation is "unfair" or who are "unsure" about fairness were less willing to donate (54%) than persons believing allocation is "fair" (68%) (p < 0.01). Associations were stronger among certain demographic subgroups. Participants with the least favorable perceptions of allocation were more likely than their counterparts to believe that race and income discrimination occur in transplantation and to believe that they personally experienced income discrimination in health care. Adjustment for these beliefs partially attenuated associations between perceptions regarding allocation and willingness to donate. Interventions enhancing transparency and perceived fairness of organ allocation may improve willingness to donate, particularly if they address concerns regarding discrimination in transplantation and health care.

Renal transplantation in the United Kingdom for patients from ethnic minorities

BACKGROUND

To investigate any differences in access to transplant and post-transplant outcomes for ethnic minority patients in the United Kingdom, national data on ethnicity of patients on the waiting list, those receiving a transplant, and deceased donors were analyzed.

METHODS

Adult patients and donors were included. Ethnic origin was classified as white, Asian, black, or "other." National data were analyzed, and 2001 U.K. National census data were used for comparative purposes. Median waiting times to transplant were obtained from Kaplan-Meier estimates for patients registered 1998-2000. Transplant survival was estimated for patients transplanted from 1998 to 2003.

RESULTS

A total of 92% of the U.K. population was white, compared with 77% of waiting list patients, 88% of transplant recipients, and 97% of deceased donors. Median waiting time to transplantation for white patients was 719 days (95% confidence interval 680-758) compared with 1368 (1131-1605) days for Asian patients and 1419 (1165-1673) days for black patients. The degree of human leukocyte antigen matching achieved was inferior for Asian and black patients. There is some evidence of inferior 3-year transplant survival for black patients compared with white and Asian patients (P=0.03).

CONCLUSIONS

There are imbalances in the ethnic make up of the waiting list, the donor pool, and renal transplant recipients. There are significant differences in both post-transplant outcomes and time to transplantation between patients of different ethnic origin. Waiting times are influenced by allocation schemes, and the 2006 U.K. National Kidney Allocation Scheme is designed to achieve greater equity of access to transplant for all patients, regardless of geography, blood group, or ethnicity.

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.

Impact of retroperitoneoscopic donor nephrectomy on renal allograft in Indian and African recipients

AIM

To evaluate the impact of laparoscopic donor nephrectomy on renal allografts in Indian and African recipients.

MATERIAL AND METHODS

Between September 2004 and August 2006, 125 retroperitoneoscopic donor nephrectomies were performed. Ninety-four donors were Indian (group A) and 32, African (group B). Three ports were used for left-sided and four for right-sided surgery, respectively. Hem-o-lok clips were used to control arteries and veins on left side and arteries on right side while an Endo-TA stapler was used on the right side to obtain an inferior vena caval cuff.

RESULTS

The mean operative times in groups A and B were 130 and 134 minutes; mean blood loss, 100.4 mL and 85.3 mL; and mean warm ischemia time, 242.1 seconds and 234.5 seconds, respectively. Recipient mean serum creatinine value on day 7 was 1.9 and 1.6 mg%, and on day 28, 1.44 mg% and 1.4 mg%, respectively.

CONCLUSION

Early adequate allograft function following retroperitoneoscopic donor nephrectomy was comparable in African and Indian patients, suggesting that no racial advantage was observed in this procedure.

Hemodialysis vintage, black ethnicity, and pretransplantation antidonor cellular immunity in kidney transplant recipients

Prolonged exposure to dialysis before transplantation and black ethnicity are known risk factors for acute rejection and graft loss in kidney transplant recipients. Because the strength of the primed antidonor T cell repertoire before transplantation also is associated with rejection and graft dysfunction, this study sought to determine whether hemodialysis (HD) vintage and/or black ethnicity affected donor-directed T cell immunity. An enzyme-linked immunosorbent spot (ELISPOT) assay was used to measure the frequency of peripheral T cells that expressed IFN-gamma in response to donor stimulator cells before transplantation in 100 kidney recipients. Acute rejection occurred in 38% of ELISPOT (+) patients versus 14% of ELISPOT (-) patients (P = 0.008). The median (HD) vintage was 46 mo (0 to 125 mo) in ELISPOT (+) patients versus 24 mo (0 to 276 mo) in ELISPOT (-) patients (P = 0.009). Black recipients had a greater median HD vintage (55 versus 14 mo in nonblack recipients; P < 0.001). Black recipients with less HD exposure had a low incidence of an ELISPOT (+) test, similar to nonblack recipients. Among variables examined, only HD vintage remained a significant positive correlate with an ELISPOT (+) result (odds ratio per year of HD 1.3; P = 0.003). These data suggest that the risk for developing cross-reactive antidonor T cell immunity increases with longer HD vintage, providing an explanation for the previously observed relationship between increased dialysis exposure and worse posttransplantation outcome. Longer HD vintage may also explain the increased T cell alloreactivity that previously was observed in black kidney recipients.

A systematic review of barriers in access to renal transplantation among African Americans in the United States

BACKGROUND

African-American patients with end-stage renal disease are less likely than white patients to undergo renal transplantation. The development of strategies to address this disparity requires an evidence-based understanding of the barriers that impede access to renal transplantation among African Americans in the United States.

METHODS

In September 2005, we searched MEDLINE, EMBASE, and CENTRAL for articles that identified the barriers that impeded African Americans' access to renal transplantation. Two reviewers independently extracted relevant data from the included studies. Barriers were broadly divided under two categories: (i) patient-related barriers; and (ii) healthcare-related barriers.

RESULTS

We obtained 76 potentially relevant articles of which 11 studies were included in the final review. Several patient-related barriers--personal and cultural beliefs about transplantation, lower socioeconomic status and levels of education, and healthcare-related barriers--physician perception about survival of African Americans post-transplantation, inadequate transplant work-up despite being referred, and HLA-mismatching were identified at different stages of the transplantation process. Personal and cultural beliefs of African-American patients were consistently identified as patient-related barriers among several studies. Physicians' perception about post-transplantation survival of African Americans was the most commonly identified healthcare-related barrier.

CONCLUSIONS

A wide spectrum of patient-related barriers including their personal and cultural beliefs about transplantation and several healthcare-related barriers at different stages of the transplant process impedes access to renal transplantation among African Americans in the United States. A multisectoral approach focusing on these barriers needs to be evaluated to reduce disparities in renal transplantation in the United States.

Infectious complications after kidney transplantation: current epidemiology and associated risk factors

BACKGROUND

The impact of newer immunosuppressive and antimicrobial prophylactic agents on the pattern of infectious complications following kidney transplantation has not been well studied.

METHODS

This is an observational study in 127 adult recipients transplanted from 2001 to 2004. Patients received thymoglobulin (ATG) (50%) or basiliximab (50%) for induction and were maintained on mycophenolate mofetil, either tacrolimus (73%) or sirolimus (SRL) (27%), and prednisone (79%). Antimicrobial prophylaxis included perioperative cefazolin, trimethoprim/sulfamethaxazole for six months, valganciclovir for three months and nystatin for two months. Regression models were used to examine the association of various factors with infections.

RESULTS

We observed 127 infections in 65 patients, consisting of urinary tract infection (UTI) (47%), viral infections (17%), pneumonia (8%) and surgical wound infections (7%). UTI was the most common infection in all post-transplant periods. Enterococcus spp. (33%) and Escherichia coli (21%) were the most prevalent uropathogens. Of six patients with cytomegalovirus infection, none had tissue-invasive disease. There were no cases of pneumocystis pneumonia or BK nephropathy. Six patients developed fungal infections. Two deaths due to disseminated Rhizopus and Candida albicans accounted for a 1.5% infection-related mortality. Retransplantation and ureteral stents were independently associated with UTI (OR=4.5 and 2.9, p=0.06 and 0.03, respectively), as were ATG and SRL with bacterial infections (OR=3.3 and 2.5, p=0.009 and 0.047, respectively).

CONCLUSION

This study suggests that the use of newer immunosuppressive agents in recent years is associated with some changes in the epidemiology of post-transplant infections. Enterococci have become the predominant uropathogen. Invasive fungal infections, although rare, are often fatal.

Renal Transplantation in High-Risk Patients

Renal transplantation in high-risk patients is a growing phenomenon. More patients are progressing to endstage renal failure, in the setting of an increased incidence of diabetes mellitus and cardiovascular disease. Current organ shortages and the use of more marginal donors have affected both patient and graft survival. Acute rejection has been minimised under modern immunosuppression; however, patient and long-term allograft outcomes have not improved concurrently. Specific understanding of donor, recipient and allograft variables associated with stratification of patients as 'high risk for renal transplantation' is necessary to facilitate appropriate peri- and post-transplant pharmacotherapy. Induction and maintenance immunosuppression choices are different for high-risk patients and must be made to ensure optimal immunosuppression, while limiting patient and allograft toxicity.

Assessment of differences in HLA-A, -B, and -DRB1 allele mismatches among African-American and non-African-American recipients of deceased kidney transplants

Among recipients of deceased donor kidney transplants, African-Americans experience a more rapid rate of kidney allograft loss than non-African-Americans. The purpose of this study was to characterize and quantify the HLA-A, -B, and -DRB1 allele mismatches and amino acid substitutions at antigen recognition sites among African-American and non-African-American recipients of deceased donor kidney transplants matched at the antigen level. In recipients with zero HLA antigen mismatches, the degree of one or two HLA allele mismatches for both racial groups combined was 47%, 29%, and 11% at HLA-DRB1, HLA-B, and HLA-A, respectively. There was a greater number of allele mismatches in African-Americans than non-African-Americans at HLA-A (P < .0001), -B (P = .096), and -DRB1 loci (P < .0001). For both racial groups, the HLA allele mismatches were predominantly at A2 for HLA-A; B35 and B44 for HLA-B; but multiple specificities for HLA-DRB1. The observed amino acid mismatches were concentrated at a few functional positions in the antigen binding site of HLA-A and -B and -DRB1 molecules. Future studies are ongoing to assess the impact of these HLA mismatches on kidney allograft loss.