Sandra Amaral

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 patients 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.

The Role of Race and Poverty on Steps to Kidney Transplantation in the Southeastern United States

Racial disparities in access to renal transplantation exist, but the effects of race and socioeconomic status (SES) on early steps of renal transplantation have not been well explored. Adult patients referred for renal transplant evaluation at a single transplant center in the Southeastern United States from 2005 to 2007, followed through May 2010, were examined. Demographic and clinical data were obtained from patients medical records and then linked with United States Renal Data System and American Community Survey Census data. Cox models examined the effect of race on referral, evaluation, waitlisting and organ receipt. Of 2291 patients, 64.9% were black, the mean age was 49.4 years and 33.6% lived in poor neighborhoods. Racial disparities were observed in access to referral, transplant evaluation, waitlisting and organ receipt. SES explained almost one‐third of the lower rate of transplant among black versus white patients, but even after adjustment for demographic, clinical and SES factors, blacks had a 59% lower rate of transplant than whites (hazard ratio = 0.41; 95% confidence interval: 0.28–0.58). Results suggest that improving access to healthcare may reduce some, but not all, of the racial disparities in access to kidney transplantation.

Racial disparities in pediatric access to kidney transplantation: does socioeconomic status play a role?

Racial disparities persist in access to renal transplantation in the United States, but the degree to which patient and neighborhood socioeconomic status (SES) impacts racial disparities in deceased donor renal transplantation access has not been examined in the pediatric and adolescent end‐stage renal disease (ESRD) population. We examined the interplay of race and SES in a population‐based cohort of all incident pediatric ESRD patients <21 years from the United States Renal Data System from 2000 to 2008, followed through September 2009. Of 8 452 patients included, 30.8% were black, 27.6% white‐Hispanic, 44.3% female and 28.0% lived in poor neighborhoods. A total of 63.4% of the study population was placed on the waiting list and 32.5% received a deceased donor transplant. Racial disparities persisted in transplant even after adjustment for SES, where minorities were less likely to receive a transplant compared to whites, and this disparity was more pronounced among patients 18–20 years. Disparities in access to the waiting list were mitigated in Hispanic patients with private health insurance. Our study suggests that racial disparities in transplant access worsen as pediatric patients transition into young adulthood, and that SES does not explain all of the racial differences in access to kidney transplantation.

Racial Disparities in Access to Pediatric Kidney Transplantation Since Share 35

Share 35 was enacted in 2005 to shorten transplant wait times and provide high-quality donors to children with ESRD. To investigate the possible effect of this policy on racial disparities in access to pediatric transplantation, we analyzed data from the US Renal Data System before and after Share 35. Among 4766 pediatric patients with incident ESRD, the probability of receiving a deceased-donor kidney transplant increased 46% after Share 35, with Hispanics experiencing the greatest improvements (increases of 81% for Hispanics, 45% for blacks, and 37% for whites). On average, patients received a deceased-donor kidney transplant earlier after Share 35, but this finding varied by race: 63 days earlier for whites, 90 days earlier for blacks, and 201 days earlier for Hispanics. Furthermore, a shift from living- to deceased-donor sources occurred with Share 35 for all races, with a 25% reduction in living donors for whites compared with 48% and 46% reductions for Hispanics and blacks, respectively. In summary, Share 35 seems to have attenuated racial disparities in the time to and probability of children receiving a deceased-donor kidney transplant. These changes coincided with changes in the rates of living-donor sources, which vary by race. Future studies should explore how these changes may impact racial differences in long-term graft outcomes.

Impact of a Patient Education Program on Disparities in Kidney Transplant Evaluation

BACKGROUND AND OBJECTIVES In 2007, the Emory Transplant Center (ETC) kidney transplant program implemented a required educational session for ESRD patients referred for renal transplant evaluation to increase patient awareness and decrease loss to follow-up. The purpose of this study was to evaluate the association of the ETC education program on completion of the transplant evaluation process. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS Incident, adult ESRD patients referred from 2005 to 2008 were included. Patient data were abstracted from medical records and linked with data from the United States Renal Data System. Evaluation completion was compared by pre- and posteducational intervention groups in binomial regression models accounting for temporal confounding. RESULTS A total of 1126 adult ESRD patients were examined in two transplant evaluation eras (75% pre- and 25% postintervention). One-year evaluation completion was higher in the post- versus preintervention group (80.4% versus 44.7%, P<0.0001). In adjusted analyses controlling for time trends, the adjusted probability of evaluation completion at 1 year was higher among the intervention versus nonintervention group (risk ratio=1.38, 95% confidence interval=1.12-1.71). The effect of the intervention was stronger among black patients and those patients living in poor neighborhoods (likelihood ratio test for interaction, P<0.05). CONCLUSIONS Standardizing transplant education may help reduce some of the racial and socioeconomic disparities observed in kidney transplantation.

Racial and ethnic differences in pediatric access to preemptive kidney transplantation in the United States.

Preemptive kidney transplantation is the optimal treatment for pediatric end stage renal disease patients to avoid increased morbidity and mortality associated with dialysis. It is unknown how race/ethnicity and poverty influence preemptive transplant access in pediatric. We examined the incidence of living donor or deceased donor preemptive transplantation among all black, white, and Hispanic children (<18 years) in the United States Renal Data System from 2000 to 2009. Adjusted risk ratios for preemptive transplant were calculated using multivariable‐adjusted models and examined across health insurance and neighborhood poverty levels. Among 8,053 patients, 1117 (13.9%) received a preemptive transplant (66.9% from LD, 33.1% from DD). In multivariable analyses, there were significant racial/ethnic disparities in access to LD preemptive transplant where blacks were 66% (RR = 0.34; 95% CI: 0.28–0.43) and Hispanics 52% (RR = 0.48; 95% CI: 0.35–0.67) less likely to receive a LD preemptive transplant versus whites. Blacks were 22% less likely to receive a DD preemptive transplant versus whites (RR = 0.78, 95% CI: 0.57–1.05), although results were not statistically significant. Future efforts to promote equity in preemptive transplant should address the critical issues of improving access to pre‐ESRD nephrology care and overcoming barriers in living donation, including obstacles partially driven by poverty.

Multidimensional Adherence Classification System: Initial development with adolescent transplant recipients

Abstract:  As transplantation has progressively become a more viable option for children with life‐threatening illness, ensuring that adolescents do not lose their new organ secondary to medication non‐adherence is paramount. The first step to addressing non‐adherence is adequate assessment of this construct. In this investigation, we introduce the MACS. The MACS includes self‐report and drug assay levels. Self‐report is a subjective measure with a low false‐positive rate, but is vulnerable to social desirability. Drug assays are an objective measure of drug ingestion, but values suggestive of non‐adherence may be influenced by medical complications and timing. The MACS builds on the strengths of both methods and attempts to contain their weaknesses. The sample in this study consisted of 82 adolescent solid organ transplant recipients. The non‐adherence rate using the MACS in this sample was 61%. Initial data to support this system are promising. The occurrence of rejection episodes and mortality were significantly related to membership in the Genuinely Non‐adherent category. Beyond providing initial support for the MACS, we discuss the clinical implications of this adherence classification system.

Surveillance renal transplant biopsies and subclinical rejection at three months post-transplant in pediatric recipients

Abstract:  Subclinical acute rejection (SCR) has been increasingly recognized in adult renal transplant recipients with the advent of surveillance biopsies. However, in children, surveillance biopsies are not routinely performed at most centers. Therefore, the incidence, predisposing factors, treatment, and clinical outcomes of SCR remain unclear in children. From August 2004 to December 2005, we performed 36 protocol biopsies at three months post‐transplantation. All patients had received induction therapy with basiliximab and were maintained on prednisone, MMF, and tacrolimus. Sixteen cases of SCR were detected by biopsy (44%). Age, gender, race, donor source, or serum creatinine did not discriminate between children with SCR and those with normal biopsies. All cases of SCR were treated with high doses of methylprednisolone. At one yr post‐transplant, renal function was similar in children with SCR to those with normal surveillance biopsies (p = 0.62). Because of the high incidence of SCR, the maintenance dose of MMF was increased by 50% in 20 children transplanted after December 2005. This resulted in a significant decline in the incidence of SCR from 44 to 15% (p < 0.05). However, the incidence of polyomavirus (BK) viremia also increased significantly in these children (p < 0.005). Conclusion: A high incidence of SCR was found on surveillance biopsies at three months post‐transplant and could not be predicted by age, gender, race, donor source, or serum creatinine. The occurrence of SCR declined significantly by increasing the dose of MMF, but resulted in an increase in BK viremia. We conclude that surveillance biopsies provide valuable information in the management of pediatric renal transplant recipients. Increasing immunosuppression to avoid SCR should be weighed against the risk for infection.

Racial and ethnic disparities in pediatric renal allograft survival in the United States.

This study was undertaken to describe the association of patient race/ethnicity and renal allograft survival among the national cohort of pediatric renal allograft recipients. Additionally, we determined whether racial and ethnic differences in graft survival exist among individuals living in low or high poverty neighborhoods and those with private or public insurance. Among 6,216 incident, pediatric End Stage Renal Disease patients in the United States Renal Data System (kidney transplant from 2000 through September, 2011) 14.4% experienced graft failure, with a median follow-up time of 4.5 years. After controlling for multiple covariates, black race, but not Hispanic ethnicity, was significantly associated with a higher rate of graft failure for both deceased and living donor transplant recipients. Disparities were particularly stark by 5 years post-transplant, when black living donor transplant recipients experienced only 63.0% graft survival compared with 82.8% and 80.8% for Hispanics and whites, respectively. These disparities persisted among high and low poverty neighborhoods and among both privately- and publicly-insured patients. Notably profound declines in both deceased and living donor graft survival rates for black, compared to white and Hispanic, children preceded the 3-year mark when transplant Medicare eligibility ends. Further research is needed to identify the unique barriers to long-term graft success among black pediatric transplant recipients.

Tacrolimus withdrawal and conversion to sirolimus at three months post-pediatric renal transplantation.

Abstract:  Nephrotoxicity caused by CNI may adversely affect long‐term graft outcomes. For this reason, we have adopted a protocol for withdrawing TAC and converting to SRL at three months post‐renal transplantation. All recipients received basiliximab induction and TAC, MMF, and prednisone. Patients without acute rejection by surveillance biopsy at three months were eligible for SRL conversion. Results: From August 2004 to September 2006, TAC was withdrawn and replaced by SRL in 30 first transplant recipients, who were followed for six to 39 months (mean 18 ± 8). Renal function did not improve significantly after SRL conversion (p = 0.25). Acute rejection occurred in three patients (10%) at five to 12 months after CNI withdrawal. There were no occurrences of wound healing problems, pneumonitis or post‐transplant lymphoproliferative disease. Thrombocytopenia and diabetes each occurred in one patient. Four patients received treatment for hypercholesterolemia. CNI withdrawal and replacement with SRL was an effective regimen in children who did not display biopsy evidence of acute rejection at three months post‐transplant. While these early results are promising, the ultimate benefit of this protocol to enhance the long‐term renal function and graft survival requires ongoing follow‐up.