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

HDL-C and creatinine levels at 1 month are associated with patient 12-month survival rate after kidney transplantation

BACKGROUND

Many factors affect the survival rate after kidney transplantation, including laboratory tests, medicine therapy and pharmacogenomics. Tacrolimus, mycophenolate mofetil and methylprednisolone were used as an immunosuppressive regimen after kidney transplantation. The primary goal of this study was to investigate the factors affecting the tacrolimus concentrations and mycophenolate mofetil area under the curve of mycophenolic acid AUC-MPA. Secondary goals were to study the association between perioperative period laboratory tests, medicine therapy, CYP3A5 genetic polymorphisms, and survival rate in kidney renal transplant patients.

METHODS

A total of 303 patients aged above 18 years were enrolled in this study. Their clinical characteristics, laboratory tests, and medicine therapy regimens were collected. We followed the patients for survival for 1 year after kidney transplantation.

RESULTS

Multivariable logistic analyses reveal that age greater than 50 years, and the CY3A5 *3*3 genotype were independently, positively, and significantly related to tacrolimus C/D ratio at 7 days. At 1 month of follow-up, only CYP3A5 *3*3 was associated with tacrolimus C/D ratio. Basiliximab, Imipenem and cilastatin sodium, sex were associated with mycophenolate mofetil AUC-MPA at 7 days. In the COX regression analysis, a high-density lipoprotein cholesterol level≥1 mmol/L was identified as a positive independent risk factors for the survival rate, while a creatinine level ≥200 μmol/L was a negatively independent risk factors for survival rate.

CONCLUSION

These results suggest that age, genes, and drug-drug interaction can affect the concentration of tacrolimus.

Increasing Access to Kidney Transplantation for Black and Asian Patients Through Modification of the Current A2 to B Allocation Policy

Key Points

A2 to B incompatible transplantation is not fully practiced in the country, and further policies should encourage centers to perform more blood incompatible transplants. Centers that currently practice A2 to B incompatible transplants should give priority to blood type B patients who are willing to accept an A organ. This will benefit Asian and Black patients.

Background

The rate of A2 to B incompatible (ABO-i) kidney transplant continues to be low despite measures in the new kidney allocation system (KAS) to facilitate such transplants. This study shows how the number of ABO-i transplants could increase if KAS policies were used to their fullest extent through a boost in ABO-i priority points.

Method

Transplant outcomes were predicted using the Kidney Pancreas Simulated Allocation Model, preloaded with national data of 2010. We used this simulation to compare KAS with a new intervention in which priority equal to cPRA=100 has been given to blood type B candidates who are willing to accept an A blood type organ.

Results

The number of Black recipients increased by 375 (from 35% of the total recipient population to 38.7%), the number of blood type B Blacks increased by 65 (from 8% of the total recipient population to 9%), and the number of blood type B Black patients receiving blood type A kidneys increased by 49 (from 2% of the total recipient population to 2.5%). The same change occurred for Asians, particularly blood type B Asians (from 0.54% of the total recipient population to 0.7%). The average wait time notably decreased by 27 days for blood type B Black patients. In the proposed scenario, 263 blood type B Black patients received a blood type A organ (2.5% of the total recipient population) while only 181 (1.1%) of such transplants were performed in 2021. These results signify a considerable opportunity loss of ABO-i transplants for Black patients.

Conclusions

If this policy was universally adopted, we would expect to see an overall increase in A2 to B transplantation, but in reality, not all centers perform ABO-i transplantation. Thus, adopting this policy would incentivize other centers to perform more subtyping of A-type kidneys, and it would increase access to organs for blood type B Asian and Black patients in centers where ABO-i transplantation already takes place.

Comparison of P-glycoprotein function in peripheral blood mononuclear cells ex vivo in stable Black and White male and female kidney transplant recipients

Kidney allograft survival remains poorer in Black compared to White recipients due to racial differences in calcineurin inhibitor (CNI) pharmacology. P-glycoprotein (P-gp), an ABC efflux transporter expressed in peripheral blood mononuclear cells (PBMCs), modulates CNI pharmacokinetics and intracellular pharmacology. This study investigated P-gp function in PBMC ex vivo at 0 (trough), 4, 8, and 12 h in stable Black and White male and female kidney transplant recipients (n = 67) receiving tacrolimus and mycophenolic acid. Tacrolimus doses were adjusted to troughs of 4-10 ng/ml. P-gp function was quantified with flow cytometric measurement of cyclosporine (CYA; 2.5 μM)-reversible efflux of P-gp substrate, 3,3'-Diethyloxacarbocyanine iodide by determining the percentage change of mean fluorescent intensity (MFI) with CYA (% ΔMFI). The composite parameter of area under the concentration versus time (AUC)0-12h % ΔMFI estimated P-gp function. Data analysis examined race, sex, and race-sex associations to P-gp function. A secondary aim analyzed ABCB1 genotypes: 1236C>T (rs1128503), 2677G>T/A (rs2032582), 3435C>T (rs1045642), and P-gp function. P-gp function (% ΔMFI) was higher in White patients at troughs (p = 0.031) compared to Black counterparts with similar trends at 4 and 8 h. Reduced AUC0-12h % ΔMFI was noted in Black recipients (N = 32) compared with Whites (N = 35, p = 0.029) with notable pairwise adjusted differences between Black and White women (p = 0.021). Higher AUC0-12h % ΔMFI was associated with ABCB1 2677 TT compared to GG variants (p = 0.035). The AUC0-12h % ΔMFI was greater in White than Black subjects. P-gp function was higher at troughs in White subjects and differed between race-sex groups. P-gp function in PBMC may influence intracellular tacrolimus exposure and inter-relating pharmacodynamic responses which may support race and sex pharmacologic differences.

Pancreas Transplantation in Minorities including Patients with a Type 2 Diabetes Phenotype

Background: Prior to year 2000, the majority of pancreas transplants (PTx) were performed as simultaneous pancreas-kidney transplants (SPKTs) in Caucasian adults with end stage renal failure secondary to type 1 diabetes mellitus (T1DM) who were middle-aged. In the new millennium, improving outcomes have led to expanded recipient selection that includes patients with a type 2 diabetes mellitus (T2DM) phenotype, which excessively affects minority populations. Methods: Using PubMed® to identify appropriate citations, we performed a literature review of PTx in minorities and in patients with a T2DM phenotype. Results: Mid-term outcomes with SPKT in patients with uremia and circulating C-peptide levels (T2DMphenotype) are comparable to those patients with T1DM although there may exist a selection bias in the former group. Excellent outcomes with SPKT suggests that the pathophysiology of T2DM is heterogeneous with elements consisting of both insulin deficiency and resistance related to beta-cell failure. As a result, increasing endogenous insulin (Cp) production following PTx may lead to freedom checking blood sugars or taking insulin, better metabolic counter-regulation, and improvements in quality of life and life expectancy compared to other available treatment options. Experience with solitary PTx for T2DM or in minorities is limited but largely mirrors the trends reported in SPKT. Conclusions: PTx is a viable treatment option in patients with pancreas endocrine failure who are selected appropriately regardless of diabetes type or recipient race. This review will summarize data that unconventional patient populations with insulin-requiring diabetes may gain value from PTx with an emphasis on contemporary experiences and appropriate selection in minorities in the new millennium.

Race and sex associations with tacrolimus pharmacokinetics in stable kidney transplant recipients

Study Objective

This study investigated race and sex differences in tacrolimus pharmacokinetics and pharmacodynamics in stable kidney transplant recipients.

Design and Setting

A cross‐sectional, open‐label, single center, 12‐h pharmacokinetic‐pharmacodynamic study was conducted. Tacrolimus pharmacokinetic parameters included area under the concentration‐time curve (AUC_0–12), AUC_0–4, 12‐h troughs (C_12 h), maximum concentrations (C_max), oral clearance (Cl), with dose‐normalized AUC_0–12, troughs, and C_max with standardized adverse effect scores. Statistical models were used to analyze end points with individual covariate‐adjustment including clinical factors, genotypic variants CYP3A5*3, CYP3A5*6, CYP3A5*7(CYP3A5*3*6*7) metabolic composite, and ATP binding cassette gene subfamily B member 1 (ABCB1) polymorphisms.

Patients

65 stable, female and male, Black and White kidney transplant recipients receiving tacrolimus and mycophenolic acid ≥6 months post‐transplant were evaluated.

Measurements and Main Results

Black recipients exhibited higher tacrolimus AUC_0–12 (Race: p = 0.005), lower AUC* (Race: p < 0.001; Race × Sex: p = 0.068), and higher Cl (Race: p < 0.001; Sex: p = 0.066). Greater cumulative (Sex: p < 0.001; Race × Sex: p = 0.014), neurologic (Sex: p = 0.021; Race × Sex: p = 0.005), and aesthetic (Sex: p = 0.002) adverse effects were found in females, with highest scores in Black women. In 84.8% of Black and 68.8% of White patients, the target AUC_0–12 was achieved (p = 0.027). In 31.3% of White and 9.1% of Black recipients, AUC_0–12 was <100 ng‧h/ml despite tacrolimus troughs in the target range (p = 0.027). The novel CYP3A5*3*6*7 metabolic composite was the significant covariate accounting for 15%–19% of tacrolimus variability in dose (p = 0.002); AUC_0–12 h* (p < 0.001), and Cl (p < 0.001).

Conclusions

Tacrolimus pharmacokinetics and adverse effects were different among stable kidney transplant recipient groups based upon race and sex with interpatient variability associated with the CYP3A5*3*6*7 metabolic composite. More cumulative, neurologic, and aesthetic adverse effects were noted among females. Tacrolimus regimens that consider race and sex may reduce adverse effects and enhance allograft outcomes by facilitating more patients to achieve the targeted AUC_0–12 h.

Simultaneous pancreas‐kidney transplantation in Caucasian versus African American patients: Does recipient race influence outcomes?

The influence of African American (AA) recipient race on outcomes following simultaneous pancreas‐kidney transplantation (SPKT) is uncertain.

Donor-Recipient Matching in Kidney Transplant: We're Not There Yet

BACKGROUND

Strategic organ allocation is expected to prolong patient and graft survival after transplant. This study explored differences in graft survival when kidneys are allocated based on strategic donor-recipient (D-R) pairing vs with the existing Kidney Allocation System (KAS).

METHODS

Using the Scientific Registry of Transplant Recipients from 2000 to 2014, we used a multivariable Cox model to assess the hazard ratios (HRs) for death or graft failure among 3 hypothetical donor kidneys transplanted into 3 hypothetical recipients, relative to an ideally matched D-R pair. Median predicted survival for each of the 9 possible D-R pairing combinations was determined, and outcomes for strategic D-R pairing were compared with those obtained using the KAS for allocation.

RESULTS

A total of 31,607 patients (29.7%) died or developed graft loss over the study period. Strategic allocation of kidneys resulted in HRs for graft loss of 1.74 (95% confidence interval [CI], 1.41-2.14), 1.82 (95% CI, 1.46-2.26), and 1.74 (95% CI 1.38-2.19) for recipients 1, 2 and 3 respectively, whereas by following the KAS, HRs were 1.93 (95%, CI 1.63-2.28), 2.06 (95% CI, 1.74-2.44), and 1.93 (95% CI, 1.58-2.37); corresponding to 3.84, 11.39, and 7.40 months longer predicted patient or graft survival for recipients 1, 2 and 3 with strategic D-R pairing compared with the KAS.

CONCLUSIONS

Allocation of kidneys by strategic D-R pairing may improve graft survival relative to allocation using the KAS.

A Narrative Review of Qualitative Studies Describing Access to Kidney Transplantation

BACKGROUND

This review used the Information-Motivation-Behavioral Skills (IMB) model of health behavior change to conceptualize the determinants of kidney transplant access behavior for adult patients with end-stage renal disease (ESRD).

METHODS

A narrative review of qualitative studies of patient access to kidney transplantation was undertaken. Only articles in English were accessed. The existing literature was critically analyzed using theoretical constructs of the IMB model and thematic synthesis was performed.

RESULTS

Results suggest patients having more information (greater transplant knowledge), more personal motivation (higher transplant outcomes expectations), more social motivation (more social and provider support), and more selfefficacy (confidence in navigating the transplant continuum) may be more likely to perform transplant access behaviors.

CONCLUSION

Our findings provide a framework for considering patients' levels of knowledge, motivation, and self-efficacy in future educational and behavioral interventions for ESRD patients.

Beyond Single Nucleotide Polymorphisms: CYP3A5∗3∗6∗7 Composite and ABCB1 Haplotype Associations to Tacrolimus Pharmacokinetics in Black and White Renal Transplant Recipients

Interpatient variability in tacrolimus pharmacokinetics is attributed to metabolism by cytochrome P-450 3A5 (CYP3A5) isoenzymes and membrane transport by P-glycoprotein. Interpatient pharmacokinetic variability has been associated with genotypic variants for both CYP3A5 or ABCB1. Tacrolimus pharmacokinetics was investigated in 65 stable Black and Caucasian post-renal transplant patients by assessing the effects of multiple alleles in both CYP3A5 and ABCB1. A metabolic composite based upon the CYP3A5 polymorphisms: ∗3(rs776746), ∗6(10264272), and ∗7(41303343), each independently responsible for loss of protein expression was used to classify patients as extensive, intermediate and poor metabolizers. In addition, the role of ABCB1 on tacrolimus pharmacokinetics was assessed using haplotype analysis encompassing the single nucleotide polymorphisms: 1236C > T (rs1128503), 2677G > T/A(rs2032582), and 3435C > T(rs1045642). Finally, a combined analysis using both CYP3A5 and ABCB1 polymorphisms was developed to assess their inter-related influence on tacrolimus pharmacokinetics. Extensive metabolizers identified as homozygous wild type at all three CYP3A5 loci were found in 7 Blacks and required twice the tacrolimus dose (5.6 ± 1.6 mg) compared to Poor metabolizers [2.5 ± 1.1 mg (P < 0.001)]; who were primarily Whites. These extensive metabolizers had 2-fold faster clearance (P < 0.001) with 50% lower AUC∗ (P < 0.001) than Poor metabolizers. No differences in C12 h were found due to therapeutic drug monitoring. The majority of blacks (81%) were classified as either Extensive or Intermediate Metabolizers requiring higher tacrolimus doses to accommodate the more rapid clearance. Blacks who were homozygous for one or more loss of function SNPS were associated with lower tacrolimus doses and slower clearance. These values are comparable to Whites, 82% of who were in the Poor metabolic composite group. The ABCB1 haplotype analysis detected significant associations of the wildtype 1236T-2677T-3435T haplotype to tacrolimus dose (P = 0.03), CL (P = 0.023), CL/LBW (P = 0.022), and AUC∗ (P = 0.078). Finally, analysis combining CYP3A5 and ABCB1 genotypes indicated that the presence of the ABCB1 3435 T allele significantly reduced tacrolimus clearance for all three CPY3A5 metabolic composite groups. Genotypic associations of tacrolimus pharmacokinetics can be improved by using the novel composite CYP3A5∗3∗4∗5 and ABCB1 haplotypes. Consideration of multiple alleles using CYP3A5 metabolic composites and drug transporter ABCB1 haplotypes provides a more comprehensive appraisal of genetic factors contributing to interpatient variability in tacrolimus pharmacokinetics among Whites and Blacks.

Unexpected Race and Ethnicity Differences in the US National Veterans Affairs Kidney Transplant Program

BACKGROUND

Racial/ethnic minorities have lower rates of deceased kidney transplantation (DDKT) and living donor kidney transplantation (LDKT) in the United States. We examined whether social determinants of health (eg, demographics, cultural, psychosocial, knowledge factors) could account for differences in the Veterans Affairs (VA) Kidney Transplantation (KT) Program.

METHODS

We conducted a multicenter longitudinal cohort study of 611 Veterans undergoing evaluation for KT at all National VA KT Centers (2010-2012) using an interview after KT evaluation and tracking participants via medical records through 2017.

RESULTS

Hispanics were more likely to get any KT (subdistribution hazard ratios [SHR] [95% confidence interval (CI)]: 1.8 [1.2-2.8]) or DDKT (SHR [95% CI]: 2.0 [1.3-3.2]) than non-Hispanic white in univariable analysis. Social determinants of health, including marital status (SHR [95% CI]: 0.6 [0.4-0.9]), religious objection to LDKT (SHR [95% CI]: 0.6 [0.4-1.0]), and donor preference (SHR [95% CI]: 2.5 [1.2-5.1]), accounted for some racial differences, and changes to Kidney Allocation System policy (SHR [95% CI]: 0.3 [0.2-0.5]) mitigated race differences in DDKT in multivariable analysis. For LDKT, non-Hispanic African American Veterans were less likely to receive an LDKT than non-Hispanic white (SHR [95% CI]: 0.2 [0.0-0.7]), but accounting for age (SHR [95% CI]: 1.0 [0.9-1.0]), insurance (SHR [95% CI]: 5.9 [1.1-33.7]), presenting with a living donor (SHR [95% CI]: 4.1 [1.4-12.3]), dialysis duration (SHR [95% CI]: 0.3 [0.2-0.6]), network of potential donors (SHR [95% CI]: 1.0 [1.0-1.1]), self-esteem (SHR [95% CI]: 0.4 [0.2-0.8]), transplant knowledge (SHR [95% CI]: 1.3 [1.0-1.7]), and changes to Kidney Allocation System policy (SHR [95% CI]: 10.3 [2.5-42.1]) in multivariable analysis eliminated those disparities.

CONCLUSIONS

The VA KT Program does not exhibit the same pattern of disparities in KT receipt as non-VA centers. Transplant centers can use identified risk factors to target patients who may need more support to ensure they receive a transplant.

Allograft and Patient Outcomes Between Indigenous and Nonindigenous Kidney Transplant Recipients

BACKGROUND

Kidney transplant outcomes of indigenous Australians are poorer compared with nonindigenous Australians, but it is unknown whether the type of acute rejection differs between these patient groups or whether rejection mediates the effect between ethnicity, death-censored graft failure (DCGF), and death with a functioning graft (DWFG).

METHODS

Biopsy-proven acute rejection (BPAR) rates and types were compared between indigenous and nonindigenous recipients. The associations between ethnicity, BPAR, DCGF, and DWFG were examined using adjusted competing risk analyses, and mediation analysis was conducted to determine whether BPAR mediated the adverse effects between ethnicity and outcomes.

RESULTS

Fifty-seven (9.3%) of 616 patients who have received kidney-only transplants between 2000 and 2010 in Western Australia were indigenous. Compared with nonindigenous recipients, BPAR rates were higher in indigenous recipients (42 versus 74 episodes/100 recipients, P < 0.01), with an excess of antibody-mediated rejections. During a median follow-up of 8 years, indigenous recipients were more likely to experience BPAR, DCGF, and DWFG compared with nonindigenous recipients, with adjusted subdistribution hazard ratio of 1.94 (1.39-2.70), 1.53 (0.85-2.76; P = 0.159), and 2.14 (1.13-4.06; P = 0.020), respectively. Although 70% of the effect between ethnicity and DCGF was mediated by BPAR, no similar association was found for DWFG.

CONCLUSIONS

Indigenous recipients experienced poorer allograft and patient outcomes compared with nonindigenous recipients, with BPAR an important determinant for DCGF. Future research identifying other risk factors and mediators associated with patient survival in indigenous recipients should be considered a priority.

Inequalities and outcomes: end stage kidney disease in ethnic minorities

Background

The international evidence about outcomes of End Stage Kidney Disease (ESKD) for ethnic minorities was reviewed to identify gaps and make recommendations for researchers and policy makers.

Methods

Nine databases were searched systematically with 112 studies from 14 different countries included and analysed to produce a thematic map of the literature.

Results

Reviews (n = 26) highlighted different mortality rates and specific causes between ethnic groups and by stage of kidney disease associated with individual, genetic, social and environmental factors. Primary studies focussing on uptake of treatment modalities (n = 19) found ethnic differences in access. Research evaluating intermediate outcomes and quality of care in different treatment phases (n = 35) e.g. dialysis adequacy, transplant evaluation and immunosuppression showed ethnic minorities were disadvantaged. This is despite a survival paradox for some ethnic minorities on dialysis seen in studies of longer term outcomes (n = 29) e.g. in survival time post-transplant and mortality. There were few studies which focussed on end of life care (n = 3) and ethnicity.

Gaps identified were: limited evidence from all stages of the ESKD pathway, particularly end of life care; a lack of system oriented studies with a reliance on national routine datasets which are limited in scope; a dearth of qualitative studies; and a lack studies from many countries with limited cross country comparison and learning.

Conclusions

Differences between ethnic groups occur at various points and in a variety of outcomes throughout the kidney care system. The combination of individual factors and system related variables affect ethnic groups differently indicating a need for culturally intelligent policy informed by research to prevent disadvantage.

Pharmacist-Led, Technology-Assisted Study to Improve Medication Safety, Cardiovascular Risk Factor Control, and Racial Disparities in Kidney Transplant Recipients

Introduction

Health disparities in African-American (AA) kidney transplant recipients compared with non-AA recipients are well established. Cardiovascular disease (CVD) risk control is a significant mediator of this disparity.

Objective

To assess the efficacy of improved medication safety, CVD risk control, and racial disparities in kidney transplant recipients.

Methods

Prospective, pharmacist-led, technology-aided, 6-month interventional clinical trial. A total of 60 kidney recipients with diabetes and hypertension were enrolled. Patients had to be at least one-year post transplant with stable graft function. Primary outcome measured included hypertension, diabetes, and lipid control using intent-to-treat analyses, with differences assessed between AA and non-AA recipients.

Results

The participants mean age was 59 years, with 42% being female and 68% being AA. Overall, patients demonstrated improvements in blood pressure <140/90 mmHg (baseline 50% vs. end of study 68%, p=0.054) and hemoglobin A1c <7% (baseline 33% vs. end of study 47%, p=0.061). AAs demonstrated a significant reduction from baseline in systolic blood pressure (-0.86 mmHg per month, p=0.026), which was not evident in non-AAs (-0.13 mmHg per month, p=0.865). Mean HgbA1c decreased from baseline in the overall group (-0.12% per month, p=0.003), which was similar within AAs (-0.11% per month, p=0.004) and non-AAs (-0.14% per month, p=0.029). There were no changes in low-density lipoproteins, triglycerides, or high-density lipoproteins over the course of the study. Medication errors were significantly reduced and self-reported medication adherence significantly improved over the course of the study.

Conclusion

These results demonstrate the potential efficacy of a pharmacist-led, technology-aided, educational intervention in improving medication safety, diabetes, and hypertension and reducing racial disparities in AA kidney transplant recipients. (ClinicalTrials.gov NCT02763943).

Nonimmunologic Donor-Recipient Pairing, HLA Matching, and Graft Loss in Deceased Donor Kidney Transplantation

Background

In kidney transplantation, nonimmunologic donor-recipient (D-R) pairing is generally not given the same consideration as immunologic matching. The aim of this study was to determine how nonimmunologic D-R pairing relates to independent donor and recipient factors, and to immunologic HLA match for predicting graft loss.

Methods

Seven D-R pairings (race, sex, age, weight, height, cytomegalovirus serostatus, and HLA match) were assessed for their association with the composite outcome of death or kidney graft loss using a Cox regression-based forward stepwise selection model. The best model for predicting graft loss (including nonimmunologic D-R pairings, independent D-R factors, and/or HLA match status) was determined using the Akaike Information Criterion.

Results

Twenty three thousand two hundred sixty two (29.9%) people in the derivation data set and 9892 (29.7%) in the validation data set developed the composite outcome of death or graft loss. A model that included both independent and D-R pairing variables best predicted graft loss. The c-indices for the derivation and validation models were 0.626 and 0.629, respectively. Size mismatch (MM) between donor and recipient (>30 kg [D < R} and >15 cm [D < R]) was associated with poor patient and graft survival even with 0 HLA MM, and conversely, an optimal D-R size pairing mitigated the risk of graft loss seen with 6 HLA MM.

Conclusions

D-R pairing is valuable in predicting patient and graft outcomes after kidney transplant. D-R size matching could offset the benefit and harm seen with 0 and 6 HLA MM, respectively. This is a novel finding.

Improving Medication Safety and Cardiovascular Risk Factor Control to Mitigate Disparities in African-American Kidney Transplant Recipients: Design and Methods

There is a lack of data analyzing the influence of cardiovascular disease (CVD) risk factor control on graft survival disparities in African-American kidney transplant recipients. Studies in the general population indicate that CVD risk factor control is poor in African-Americans, leading to higher rates of renal failure and major acute cardiovascular events. However, with the exception of hypertension, there is no data demonstrating similar results within transplant recipients. Recent analyses conducted by our investigator group indicate that CVD risk factors, especially diabetes, are poorly controlled in African-American recipients, which likely impacts graft loss. This study protocol describes a prospective interventional clinical trial with the goal of demonstrating improved medication safety and CVD risk factor control in adult solitary kidney transplant recipients at least one-year post-transplant with a functioning graft. This is a prospective, interventional, 6-month, pharmacist-led and technology enabled study in adult kidney transplant recipients with the goal of improving CVD risk factor outcomes by improving medication safety and patient self-efficacy. This papers describes the issues related to racial disparities in transplant, the details of this intervention and how we expect this intervention to improve CVD risk factor control in kidney transplant recipients, particularly within African-Americans.

Has the Department of Veterans Affairs Found a Way to Avoid Racial Disparities in the Evaluation Process for Kidney Transplantation?

BACKGROUND

Minority groups are affected by significant disparities in kidney transplantation (KT) in Veterans Affairs (VA) and non-VA transplant centers. However, prior VA studies have been limited to retrospective, secondary database analyses that focused on multiple stages of the KT process simultaneously. Our goal was to determine whether disparities during the evaluation period for KT exist in the VA as has been found in non-VA settings.

METHODS

We conducted a multicenter longitudinal cohort study of 602 patients undergoing initial evaluation for KT at 4 National VA KT Centers. Participants completed a telephone interview to determine whether, after controlling for medical factors, differences in time to acceptance for transplant were explained by patients' demographic, cultural, psychosocial, or transplant knowledge factors.

RESULTS

There were no significant racial disparities in the time to acceptance for KT [Log-Rank χ = 1.04; P = 0.594]. Younger age (hazards ratio [HR], 0.98; 95% confidence interval [CI], 0.97-0.99), fewer comorbidities (HR, 0.89; 95% CI, 0.84-0.95), being married (HR, 0.81; 95% CI, 0.66-0.99), having private and public insurance (HR, 1.29; 95% CI, 1.03-1.51), and moderate or greater levels of depression (HR, 1.87; 95% CI, 1.03-3.29) predicted a shorter time to acceptance. The influence of preference for type of KT (deceased or living donor) and transplant center location on days to acceptance varied over time.

CONCLUSIONS

Our results indicate that the VA National Transplant System did not exhibit the racial disparities in evaluation for KT as have been found in non-VA transplant centers.

Quantifying the Race Stratified Impact of Socioeconomics on Graft Outcomes in Kidney Transplant Recipients

BACKGROUND

Socioeconomic status (SES) is a significant determinant of health outcomes and may be an important component of the causal chain surrounding racial disparities in kidney transplantation. The social adaptability index (SAI) is a validated and quantifiable measure of SES, with a lack of studies analyzing this measure longitudinally or between races.

METHODS

Longitudinal cohort study in adult kidney transplantation transplanted at a single-center between 2005 and 2012. The SAI score includes 5 domains (employment, education, marital status, substance abuse and income), each with a minimum of 0 and maximum of 3 for an aggregate of 0 to 15 (higher score → better SES).

RESULTS

One thousand one hundred seventy-one patients were included; 624 (53%) were African American (AA) and 547 were non-AA. African Americans had significantly lower mean baseline SAI scores (AAs 6.5 vs non-AAs 7.8; P < 0.001). Cox regression analysis demonstrated that there was no association between baseline SAI and acute rejection in non-AAs (hazard ratio [HR], 0.92; 95% confidence interval [95% CI], 0.81-1.05), whereas it was a significant predictor of acute rejection in AAs (HR, 0.89; 95% CI, 0.80-0.99). Similarly, a 2-stage approach to joint modelling of time to graft loss and longitudinal SAI did not predict graft loss in non-AAs (HR, 1.01; 95% CI, 0.28-3.62), whereas it was a significant predictor of graft loss in AAs (HR, 0.23; 95% CI, 0.06-0.93).

CONCLUSIONS

After controlling for confounders, SAI scores were associated with a lower risk of acute rejection and graft loss in AA kidney transplant recipients, whereas neither baseline nor follow-up SAI predicted outcomes in non-AA kidney transplant recipients.

Outcome disparities between African Americans and Caucasians in contemporary kidney transplant recipients

BACKGROUND

Racial disparities in African-American (AA) kidney transplant have persisted for nearly 40 years, with limited data available on the scope of this issue in the contemporary era of transplantation.

METHODS

Descriptive retrospective cohort study of US registry data including adult solitary kidney transplants between Jan 1, 2005 to Dec 31, 2009.

RESULTS

60,695 recipients were included; 41,426 Caucasians (68%) and 19,269 AAs (32%). At baseline, AAs were younger, had lower college graduation rates, were more likely to be receiving public health insurance and have diabetes. At one-year post-transplant, AAs had 62% higher risk of graft loss (RR 1.62, 95% CI 1.50-1.75) which increased to 93% at five years (RR 1.93, 95% CI 1.85-2.01). Adjusted risk of graft loss, accounting for baseline characteristics, was 60% higher in AAs (HR 1.61 [1.52-1.69]). AAs had significantly higher risk of acute rejection and delayed graft function.

CONCLUSION

AAs continue to experience disproportionately high rates of graft loss within the contemporary era of transplant, which are related to a convergence of an array of socioeconomic and biologic risk factors.

Twenty years of evolving trends in racial disparities for adult kidney transplant recipients

Disparities in outcomes for African American (AA) kidney transplant recipients have persisted for 40 years without a comprehensive analysis of evolving trends in the risks associated with this disparity. Here we analyzed U.S. transplant registry data, which included adult Caucasian or AA solitary kidney recipients undergoing transplantation between 1990 and 2009 comprising 202,085 transplantations. During this 20-year period, the estimated rate of 5-year graft loss decreased from 27.6% to 12.8%. Notable trends in baseline characteristics that significantly differed by race over time included the following: increased prevalence of diabetes from 2001 to 2009 in AAs (5-year slope difference: 3.4%), longer time on the waiting list (76.5 more days per 5 years in AAs), fewer living donors in AAs from 2003 to 2009 (5-year slope difference: -3.36%), more circulatory death donors in AAs from 2000-09 (5-year slope difference: 1.78%), and a slower decline in delayed graft function in AAs (5-year slope difference: 0.85%). The absolute risk difference between AAs and Caucasians for 5-year graft loss significantly declined over time (-0.92% decrease per 5 years), whereas the relative risk difference actually significantly increased (3.4% increase per 5 years). These results provide a mixed picture of both promising and concerning trends in disparities for AA kidney transplant recipients. Thus, although the disparity for graft loss has significantly improved, equity is still far off, and other disparities, including living donation rates and delayed graft function rates, have widened during this time.

Impact of Cardiovascular Risk Factors on Graft Outcome Disparities in Black Kidney Transplant Recipients

Although outcome inequalities for non-Hispanic black (NHB) kidney transplant recipients are well documented, there is paucity in data assessing the impact of cardiovascular disease (CVD) risk factors on this disparity in kidney transplantation. This was a longitudinal study of a national cohort of veteran kidney recipients transplanted between January 2001 and December 2007. Data included baseline characteristics acquired through the United States Renal Data System linked to detailed clinical follow-up information acquired through the Veterans Affairs electronic health records. Analyses were conducted using sequential multivariable modeling (Cox regression), incorporating blocks of variables into iterative nested models; 3139 patients were included (2095 non-Hispanic whites [66.7%] and 1044 NHBs [33.3%]). NHBs had a higher prevalence of hypertension (100% versus 99%; P<0.01) and post-transplant diabetes mellitus (59% versus 53%; P<0.01) with reduced control of hypertension (blood pressure <140/90 60% versus 69%; P<0.01), diabetes mellitus (A1c <7%, 35% versus 47%; P<0.01), and low-density lipoprotein (<100 mg/dL, 55% versus 61%; P<0.01). Adherence to medications used to manage CVD risk was significantly lower in NHBs. In the fully adjusted models, the independent risk of graft loss in NHBs was substantially reduced (unadjusted hazard ratio, 2.00 versus adjusted hazard ratio, 1.49). CVD risk factors and control reduced the influence of NHB race by 9% to 18%. Similar trends were noted for mortality, and estimates were robust across in sensitivity analyses. These results demonstrate that NHB kidney transplant recipients have significantly higher rates of CVD risk factors and reduced CVD risk control. These issues are likely partly related to medication nonadherence and meaningfully contribute to racial disparities for graft outcomes.

A2 /A2 B to B Renal Transplantation: Past, Present, and Future Directions

One component of the new national kidney allocation system (KAS) in the United States that was implemented on December 4, 2014, was the allocation of kidneys from A2 and A2 B (A, non-A1 and AB, non-A1 B) deceased donors into blood group B candidates (A2 /A2 B → B). In so far as this is an important component of the new KAS that has the potential to further increase the access to transplantation for blood group B candidates on the waiting list, most of whom are minority candidates, we will review the body of evidence and historical perspectives that led to its inclusion in the new KAS. This review will also describe prospects for more widespread use of A2 /A2 B → B transplantation and a novel mechanism of humoral immunosuppression in B patients before and after transplantation with an A2 or A2 B kidney.

First Report on the OPTN National Variance: Allocation of A2 /A2 B Deceased Donor Kidneys to Blood Group B Increases Minority Transplantation

In 2002, the Organ Procurement and Transplantation Network (OPTN) Minority Affairs Committee (MAC) implemented a national, prospective, "variance of practice" to allow deceased donor, ABO blood group incompatible, A2 antigen, kidney transplantation into blood group B recipients; outcomes of this cohort were compared to ABO compatible recipients. The goal of the variance was to increase the number of transplants to B candidates without negatively impacting survival or compromising system equity. Only B recipients with low anti-A IgG titers (<1:8) were eligible to receive these kidneys. Across eight participating Donation Service Areas (DSA), there were 101 A2 /A2 B to B transplants through 12/31/11, of which the majority of the recipients (61%) were ethnic minorities. At 12, 24, and 36 months, Kaplan-Meier graft survival rates for the B recipients of A2 /A2 B kidneys were 95.0%, 90.6%, and 85.4%, respectively, comparable to outcomes for B recipients of B kidneys, 92.6%, 87.9%, and 82.5%, respectively (p-value = 0.48). Five DSAs increased the proportion of B transplants during 41 months postvariance, with a lesser proportional decrease in blood group A transplants. The data support the proposition that this allocation algorithm may provide a robust mechanism to increase access of blood group B minority candidates to kidney transplantation.

Association of time to kidney transplantation with graft failure among U.S. patients with end-stage renal disease due to lupus nephritis

OBJECTIVE

Providers recommend waiting to transplant patients with end-stage renal disease (ESRD) secondary to lupus nephritis (LN), to allow for quiescence of systemic lupus erythematosus (SLE)-related immune activity. However, these recommendations are not standardized, and we sought to examine whether duration of time to transplant was associated with risk of graft failure in US LN-ESRD patients.

METHODS

Using national ESRD surveillance data (United States Renal Data System), we identified 4,743 US patients with LN-ESRD who received a first transplant on or after January 1, 2000 (followup through September 30, 2011). The association of wait time (time from ESRD start to transplant) with graft failure was assessed with Cox proportional hazards models, with splines of the exposure to allow for nonlinearity of the association and with adjustment for potential confounding by demographic, clinical, and transplant factors.

RESULTS

White LN-ESRD patients who were transplanted later (versus at <3 months receiving dialysis) were at increased risk of graft failure (3-12 months: adjusted hazard ratio [HR] 1.23, 95% confidence interval [95% CI] 0.93-1.63; 12-24 months: adjusted HR 1.37, 95% CI 0.92-2.06; 24-36 months: adjusted HR 1.34, 95% CI 0.92-1.97; and >36 months: adjusted HR 1.98, 95% CI 1.31-2.99). However, no such association was seen among African American recipients (3-12 months: adjusted HR 1.07, 95% CI 0.79-1.45; 12-24 months: adjusted HR 1.01, 95% CI 0.64-1.60; 24-36 months: adjusted HR 0.78, 95% CI 0.51-1.18; and >36 months: adjusted HR 0.74, 95% CI 0.48-1.13).

CONCLUSION

While future studies are needed to examine the potential confounding effect of clinically recognized SLE activity on the observed associations, these results suggest that longer wait times to transplant may be associated with equivalent or worse, not better, graft outcomes among LN-ESRD patients.

Applying best practices to designing patient education for patients with end-stage renal disease pursuing kidney transplant

Despite the known benefits of kidney transplant, less than 30% of the 615 000 patients living with end-stage renal disease (ESRD) in the United States have received a transplant. More than 100 000 people are presently on the transplant waiting list. Although the shortage of kidneys for transplant remains a critical factor in explaining lower transplant rates, another important and modifiable factor is patients' lack of comprehensive education about transplant. The purpose of this article is to provide an overview of known best practices from the broader literature that can be used as an evidence base to design improved education for ESRD patients pursuing a kidney transplant. Best practices in chronic disease education generally reveal that education that is individually tailored, understandable for patients with low health literacy, and culturally competent is most beneficial. Effective education helps patients navigate the complex health care process successfully. Recommendations for how to incorporate these best practices into transplant education design are described. Providing more ESRD patients with transplant education that encompasses these best practices may improve their ability to make informed health care decisions and increase the numbers of patients interested in pursuing transplant.

Readiness of wait-listed black patients to pursue live donor kidney transplant

CONTEXT

For adults with end-stage kidney disease, live donor kidney transplant (LDKT) has better outcomes than long-term dialysis and deceased donor kidney transplant. However, black patients receive LDKT at a much lower rate than adults of any other race or ethnicity.

OBJECTIVE

To examine the LDKT readiness stage of black patients on the transplant waiting list and its association with LDKT knowledge, concerns, and willingness.

DESIGN

Cross-sectional analysis of baseline data from a randomized controlled trial to improve knowledge and reduce concerns about LDKT.Patients and Setting-One hundred fifty-two black patients on the kidney transplant waiting list at a single transplant center in the northeastern United States.

MAIN OUTCOME MEASURES

LDKT readiness stage, knowledge, concerns, and willingness to talk to others about living donation.

RESULTS

Sixty percent of patients were not considering or not yet ready to pursue LDKT, and only 11% had taken action to talk to family members or friends about the possibility of living kidney donation. Patients in later stages of LDKT readiness (ie, who had talked to others about donation or were preparing to do so) had significantly more knowledge (P<.001), fewer concerns (P=.002), and more willingness (P=.001) to talk to others about living donation than those in earlier readiness stages.

CONCLUSIONS

The large percentage of black patients who are in the earlier stages of LDKT readiness may account for the low rate of LDKT in this patient population at our transplant center. Innovative and tailored LDKT educational strategies for black patients are needed to help reduce racial disparities in LDKT.

Understanding African American's religious beliefs and organ donation intentions

African Americans are overrepresented on the organ transplant waiting list and underrepresented among organ and tissue donors. One of the most highly noted reasons for lack of donation is the perception that donation is contrary to religious beliefs. The purpose of this cross-sectional study is to explore the complexities of religion (beliefs, religiosity, and religious involvement) and its association with willingness to donate and the written expression of donation intentions. Findings from a sample of 505 African American participants suggest that religion is a multidimensional construct and results differ depending on how the construct is measured and operationalized.

Significant racial differences in the key factors associated with early graft loss in kidney transplant recipients

BACKGROUND

There is continued and significant debate regarding the salient etiologies associated with graft loss and racial disparities in kidney transplant recipients.

METHODS

This was a longitudinal cohort study of all adult kidney transplant recipients, comparing patients with early graft loss (<5 years) to those with graft longevity (surviving graft with at least 5 years of follow-up) across racial cohorts [African-American (AA) and non-AA] to discern risk factors.

RESULTS

524 patients were included, 55% AA, 151 with early graft loss (29%) and 373 with graft longevity (71%). Consistent within both races, early graft loss was significantly associated with disability income [adjusted odds ratio (AOR) 2.2, 95% CI 1.1-4.5], Kidney Donor Risk Index (AOR 3.2, 1.4-7.5), rehospitalization (AOR 2.1, 1.0-4.4) and acute rejection (AOR 4.4, 1.7-11.6). Unique risk factors in AAs included Medicare-only insurance (AOR 8.0, 2.3-28) and BK infection (AOR 5.6, 1.3-25). Unique protective factors in AAs included cardiovascular risk factor control: AAs with a mean systolic blood pressure <150 mm Hg had 80% lower risk of early graft loss (AOR 0.2, 0.1-0.7), while low-density lipoprotein <100 mg/dl (AOR 0.4, 0.2-0.8), triglycerides <150 mg/dl (AOR 0.4, 0.2-1.0) and hemoglobin A1C <7% (AOR 0.2, 0.1-0.6) were also protective against early graft loss in AA, but not in non-AA recipients.

CONCLUSIONS

AA recipients have a number of unique risk factors for early graft loss, suggesting that controlling cardiovascular comorbidities may be an important mechanism to reduce racial disparities in kidney transplantation.

Donor and recipient size mismatch in adolescents undergoing living-donor renal transplantation affect long-term graft survival

BACKGROUND

Controversies exist in the adult literature regarding the use of kidneys from small donors into larger recipients. Little is known regarding this issue in pediatric kidney transplantation. To assess the impact of donor/recipient size mismatch on long-term renal graft survival in pediatric patients undergoing living-donor renal transplantation.

METHODS

We reviewed the United Network for Organ Sharing database from 1987 to 2010 for adolescent (11-18 years old) patients who underwent primary living-donor renal transplantation. According to donor/recipient body surface area (BSA) ratio, patients were stratified into two categories: BSA ratio <0.9 and ≥0.9. Graft survival rates were compared between these two groups using Kaplan-Meier survival curves and Cox proportional hazards models.

RESULTS

Of the 1880 patients identified, 116 (6.2%) had a donor/recipient BSA ratio <0.9 and 1764 (93.8%) had a donor/recipient BSA ratio ≥0.9 group. BSA ratio <0.9 conferred an increased risk of graft loss (adjusted hazard ratio, 1.61; 95% confidence interval, 1.13-2.27; P=0.008). Patients with a donor/recipient BSA ratio ≥0.9 group had a significantly longer graft survival compared with those with a donor/recipient BSA ratio <0.9 after adjustment for donor age and gender, recipient age, gender, ethnicity, cause of renal failure, as well as clinical factors, such as cold and warm ischemia time and HLA mismatch.

CONCLUSION

We conclude that low donor/recipient BSA ratio was associated with an increased risk of graft loss. Appropriate size matching conferred better long-term graft survival in adolescents receiving live-donor kidney transplants.

The impact of cardiovascular disease and risk factor treatment on ethnic disparities in kidney transplant

There is limited data on the use of cardiovascular disease (CVD) risk factor medications following renal transplant, especially when comparing use across ethnicities. The aim of this study was to compare the incidence, treatment, and impact of CVD between ethnicities in kidney transplant recipients. This was a retrospective cohort study of adults who underwent transplant between 2000 and 2008 within our academic medical transplant center. Pediatrics, multiorgan transplants, and those lost to follow-up were excluded. Data collection included all transplant and sociodemographic characteristics, medication use, CVD risk factor management, and follow-up events, including acute rejection, graft loss, and death. A total of 987 patients were included and followed for a mean of 6.7 ± 3.0 years. The baseline demographics revealed black patients were equally likely to have preexisting CVD (24% vs 25%, P = .651), but more likely to have preexisting diabetes (35% vs 23%, P < .001) or hypertension (97% vs 94%, P = .029). Black patients had poorer treatment of CVD risk factors, with lower rates of control of diabetes (35% vs 51%, P < .05) and dyslipidemia (37% vs 42%, P < .05). Black renal transplant recipients who had preexisting CVD had reduced graft survival rates compared to white patients (10-year rate 50% vs 60%, P = .033), but similar rates of graft survival were found in those without CVD (10-year rate 70% vs 71% in white patients, P = .483). CVD is common in transplant recipients, with black patients having higher rates and poorer control of diabetes and dyslipidemia.

Ethnic differences in the accumulation of fat and lean mass in late gestation

OBJECTIVES

Lower birth weight within the normal range predicts adult chronic diseases, but the same birth weight in different ethnic groups may reflect different patterns of tissue development. Neonatal body composition was investigated among non-Hispanic Caucasians and African Americans, taking advantage of variability in gestational duration to understand growth during late gestation.

METHODS

Air displacement plethysmography assessed fat and lean body mass among 220 non-Hispanic Caucasian and 93 non-Hispanic African American neonates. The two ethnic groups were compared using linear regression.

RESULTS

At 36 weeks of gestation, the average lean mass of Caucasian neonates was 2,515 g vs. that of 2,319 g of African American neonates (difference, P = 0.02). The corresponding figures for fat mass were 231 and 278 g, respectively (difference, P = 0.24). At 41 weeks, the Caucasians were 319 g heavier in lean body mass (P < 0.001) but were also 123 g heavier in fat mass (P = 0.001). The slopes for lean mass vs. gestational week were similar, but the slope of fat mass was 5.8 times greater (P = 0.009) for Caucasian (41.0 g/week) than for African American neonates (7.0 g/week).

CONCLUSIONS

By 36 weeks of gestation, the African American fetus developed similar fat mass and less lean mass compared with the Caucasian fetus. Thereafter, changes in lean mass among the African American fetus with increasing gestational age at birth were similar to the Caucasian fetus, but fat accumulated more slowly. We hypothesize that different ethnic fetal growth strategies involving body composition may contribute to ethnic health disparities in later life.

Perceived discrimination predicts longer time to be accepted for kidney transplant

BACKGROUND

Although end-stage kidney disease in African Americans (AAs) is four times greater than in whites, AAs are less than one half as likely to undergo kidney transplantation (KT). This racial disparity has been found even after controlling for clinical factors such as comorbid conditions, dialysis vintage and type, and availability of potential living donors. Therefore, studying nonmedical factors is critical to understanding disparities in KT.

METHODS

We conducted a longitudinal cohort study with 127 AA and white patients with end-stage kidney disease undergoing evaluation for KT (December 2006 to July 2007) to determine whether, after controlling for medical factors, differences in time to acceptance for transplant is explained by patients' cultural factors (e.g., perceived racism and discrimination, medical mistrust, religious objections to living donor KT), psychosocial characteristics (e.g., social support, anxiety, depression), or transplant knowledge. Participants completed two telephone interviews (shortly after initiation of transplant evaluation and after being accepted or found ineligible for transplant).

RESULTS

Results indicated that AA patients reported higher levels of the cultural factors than did whites. We found no differences in comorbidity or availability of potential living donors. AAs took significantly longer to get accepted for transplant than did whites (hazard ratio=1.49, P=0.005). After adjustment for demographic, psychosocial, and cultural factors, the association of race with longer time for listing was no longer significant.

CONCLUSIONS

We suggest that interventions to address racial disparities in KT incorporate key nonmedical risk factors in patients.

The "House Calls" trial: a randomized controlled trial to reduce racial disparities in live donor kidney transplantation: rationale and design

Despite a substantially lower rate of live donor kidney transplantation among Black Americans compared to White Americans, there are few systematic efforts to reduce this racial disparity. This paper describes the rationale and design of a randomized controlled trial evaluating the comparative effectiveness of three different educational interventions for increasing live donor kidney transplantation in Black Americans. This trial is a single-site, urn-randomized controlled trial with a planned enrollment of 180 Black Americans awaiting kidney transplantation. Patients are randomized to receive transplant education in one of three education conditions: through group education at their homes (e.g., House Calls), or through group (Group-Based) or individual education (Individual Counseling) in the transplant center. The primary outcome of the trial is the occurrence of a live donor kidney transplant, with secondary outcomes including living donor inquiries and evaluations as well as changes in patient live donor kidney transplantation readiness, willingness, knowledge, and concerns. Sex, age, dialysis status, and quality of life are evaluated as moderating factors. Findings from this clinical trial have the potential to inform strategies for reducing racial disparities in live donor kidney transplantation. Similar trials have been developed recently to broaden the evaluation of House Calls as an innovative disparity-reducing intervention in kidney transplantation.

Center-level factors and racial disparities in living donor kidney transplantation

BACKGROUND

On average, African Americans attain living donor kidney transplantation (LDKT) at decreased rates compared with their non-African American counterparts. However, center-level variations in this disparity or the role of center-level factors is unknown.

STUDY DESIGN

Observational cohort study.

SETTING & PARTICIPANTS

247,707 adults registered for first-time kidney transplants from 1995-2007 as reported by the Scientific Registry of Transplant Recipients.

PREDICTORS

Patient-level factors (age, sex, body mass index, insurance status, education, blood type, and panel-reactive antibody level) were adjusted for in all models. The association of center-level characteristics (number of candidates, transplant volume, LDKT volume, median time to transplant, percentage of African American candidates, percentage of prelisted candidates, and percentage of LDKT) and degree of racial disparity in LDKT was quantified.

OUTCOMES

Hierarchical multivariate logistic regression models were used to derive center-specific estimates of LDKT attainment in African American versus non-African American candidates.

RESULTS

Racial parity was not seen at any of the 275 transplant centers in the United States. At centers with the least racial disparity, African Americans had 35% lower odds of receiving LDKT; at centers with the most disparity, African Americans had 76% lower odds. Higher percentages of African American candidates (interaction term, 0.86; P = 0.03) and prelisted candidates (interaction term, 0.80; P = 0.001) at a given center were associated with increased racial disparity at that center. Higher rates of LDKT (interaction term, 1.25; P < 0.001) were associated with less racial disparity.

LIMITATIONS

Some patient-level factors are not captured, including a given patient's pool of potential donors. Geographic disparities in deceased donor availability might affect LDKT rates. Center-level policies and practices are not captured.

CONCLUSIONS

Racial disparity in attainment of LDKT exists at every transplant center in the country. Centers with higher rates of LDKT attainment for all races had less disparity; these high-performing centers might provide insights into policies that might help address this disparity.

Persistent racial disparities in survival after heart transplantation

BACKGROUND

Racial and ethnic disparities are well documented in many areas of health care, but have not been comprehensively evaluated among recipients of heart transplants.

METHODS AND RESULTS

We performed a retrospective cohort study of 39075 adult primary heart transplant recipients from 1987 to 2009 using national data from the United Network of Organ Sharing and compared mortality for nonwhite and white patients using the Cox proportional hazards model. During the study period, 8082 nonwhite and 30 993 white patients underwent heart transplantation. Nonwhite heart transplant recipients increased over time, comprising nearly 30% of transplantations since 2005. Nonwhite recipients had a higher clinical risk profile than white recipients at the time of transplantation, but had significantly higher posttransplantation mortality even after adjustment for baseline risk. Among the nonwhite group, only black recipients had an increased risk of death compared with white recipients after multivariable adjustment for recipient, transplant, and socioeconomic factors (hazard ratio, 1.34; 95% confidence interval, 1.21 to 1.47; P<0.001). Five-year mortality was 35.7% (95% confidence interval, 35.2 to 38.3) among black and 26.5% (95% confidence interval, 26.0 to 27.0) among white recipients. Black patients were more likely to die of graft failure or a cardiovascular cause than white patients, but less likely to die of infection or malignancy. Although mortality decreased over time for all transplant recipients, the disparity in mortality between blacks and whites remained essentially unchanged.

CONCLUSIONS

Black heart transplant recipients have had persistently higher mortality than whites recipients over the past 2 decades, perhaps because of a higher rate of graft failure.

Racial and ethnic disparities in kidney transplantation

Success of renal transplantation, as a viable alternative to dialysis, has been tempered by long-standing racial disparities. Ethnic minorities have less access to transplantation, are less likely to be listed for transplantation, and experience a higher rate of graft failure. Reasons for the existing racial disparities at various stages of the transplantation process are complex and multi-factorial. They include a combination of behavioral, social, environmental, and occupational factors, as well as potential intended or unintended discrimination within the healthcare system. Immunologic factors such as human leukocyte antigen matching, composition of the organ donor pool, and patient immune response, all of which affect post-transplantation graft rejection rates and patient survival, also contribute to health disparities between ethnic groups.

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.

African American kidney transplantation survival: the ability of immunosuppression to balance the inherent pre- and post-transplant risk factors

Among organ transplant recipients, the African American population historically has received special attention. This is because secondary to their disposition to certain disease states, for example hypertension, an African American patient has a propensity to reach end-stage renal disease and require renal replacement earlier than a Caucasian patient. Regardless of the initiative to replace dialysis therapy with organ transplantation, the African American patient has many barriers to kidney transplantation, thus extending their time on dialysis and waiting time on the organ transplant list. These factors are among the many negative causes of decreased kidney graft survival, realized before kidney transplantation. Unfortunately, once the African American recipient receives a kidney graft, the literature documents that many post-transplant barriers exist which limit successful outcomes. The primary post-transplant barrier relates to designing proper immunosuppression protocols. The difficulty in designing protocols revolves around (i) altered genetic metabolism/lower absorption, (ii) increased immuno-active cytokines and (iii) detrimental effects of noncompliance. Based on the literature, dosing of immunosuppression must be aggressive and requires a diligent practitioner. Research has indicated that, despite some success with proven levels of immunosuppression, the African American recipient usually requires a higher 'dose per weight' regimen. However, even with aggressive immunosuppressant dosing, African Americans still have worse outcomes than Caucasian recipients. Additionally, many of the targeted sites of action that immunosuppression exerts its effects on have been found to be amplified in the African American population. Finally, noncompliance is the most discouraging inhibitor of long-term success in organ transplantation. The consequences of noncompliance are biased by ethnicity and affect the African American population more severely. All of these factors are discussed further in this review in the hope of identifying an ideal healthcare model for caring for the African American transplant recipient, from diagnosing chronic kidney disease through to successful kidney graft outcomes. An indepth review of the literature is described and organized in a fashion that highlights all of the issues affecting success in African Americans. The compilation of the literature in this review will enable the reader to get closer to understanding the caveats of kidney transplantation in the African American patient, but falls short of delivering an actual 'equation' for post-transplant care in an African American kidney recipient.

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.

Equivalent outcomes with primary and retransplantation in African-American deceased-donor renal allograft recipients

BACKGROUND

Graft survival following renal retransplantation has been inferior to that following primary allografting, particularly in African Americans (AAs) receiving deceased-donor (DD) kidneys.

METHODS

Among 166 AA DD renal allograft recipients transplanted from July 2001 through July 2007, we compared the outcomes of 26 (16%) receiving a second graft with those of 140 primary cases. All patients received either thymoglobulin (ATG) or an IL-2 receptor antagonist for induction, and were maintained on either tacrolimus or sirolimus + mycophenolate mofetil +/- prednisone.

RESULTS

When compared with primary transplants, regrafts received kidneys from older donors, were younger, more sensitized, more likely to receive ATG and to be maintained on prednisone, received more doses of ATG, and were less likely diabetic. There was no difference between primary and retransplant groups in overall patient or graft survival; incidence of acute rejection, CMV infection, BK nephropathy, or new-onset diabetes mellitus; and serum creatinine at 1 year.

CONCLUSION

AA renal allograft recipients can undergo a second DD transplant with intermediate-term outcomes comparable to that of a primary graft, despite the presence of multiple immunologic and non-immunologic high-risk factors, by extending the course of ATG induction and continuing prednisone therapy in the vast majority of cases.

Longitudinal analysis of physical activity, fluid intake, and graft function among kidney transplant recipients

Self-care is recommended to kidney transplant recipients as a vital component to maintain long-term graft function. However, little is known about the effects of physical activity, fluid intake, and smoking history on graft function. This longitudinal study examined the relationship between self-care practices on graft function among 88 new kidney transplant recipients in Chicago, IL and Albany, NY between 2005 and 2008. Participants were interviewed, completed surveys, and medical charts were abstracted. Physical activity, fluid intake, and smoking history at baseline were compared with changes in estimated glomerular filtration rate (eGFR) (every 6 months up to 1 year) using bivariate and multivariate regression analysis, while controlling for sociodemographic and clinical transplant variables. Multivariate analyses revealed that greater physical activity was significantly (P < 0.05) associated with improvement in GFR at 6 months; while greater physical activity, absence of smoking history, and nonwhite ethnicity were significant (P < 0.05) predictors of improvement in GFR at 12 months. These results suggest that increasing physical activity levels in kidney recipients may be an effective behavioral measure to help ensure graft functioning. Our findings suggest the need for a randomized controlled trial of exercise, fluid intake, and smoking history on GFR beyond 12 months.

The importance of emergency medicine in organ donation: successful donation is more likely when potential donors are referred from the emergency department

OBJECTIVES

This study sought to identify factors that are associated with successful organ retrieval among patients referred to organ procurement services for potential organ donation. Particular attention was paid to the frequency, patient characteristics, and outcomes of patients referred for donation from the emergency department (ED).

METHODS

For this retrospective cohort study, data were collected on all solid-organ donor referrals made to a single organ procurement organization serving 78 hospitals over a 45-month period. Data retrieved included patient age, sex, race, referral site (ED vs. inpatient), and mechanism of injury. Outcome of referral (organs retrieved or not) was the primary outcome variable. Pearson chi-square and Student's t-tests were used for bivariate statistical analysis. Multiple logistic regression analysis was used to determine which variables remained associated with organ retrieval after controlling for potential confounders.

RESULTS

A total of 6,886 donor referrals were made in the study population. Of these, 155 were excluded due to incomplete data, leaving 6,731 subjects for analysis. Using bivariate statistical analysis, we found that successful organ retrieval was associated with younger age (donor mean age 40.8 years, 95% confidence interval [CI] = 39.1 to 42.5 vs. nondonor mean age 59.4, 95% CI = 58.9 to 59.9), mechanism of injury (p < 0.001), and referral from the ED (ED 15.5% retrieved, inpatient 5.9%, odds ratio [OR] = 2.92, 95% CI = 2.32 to 3.67). After controlling for potential confounders with multiple logistic regression, referral from the ED remained significantly associated with successful organ retrieval (OR = 1.52, 95% CI = 1.18 to 1.97), as did age (OR = 0.96, 95% CI = 0.96 to 0.97) and mechanism of injury (p < 0.001). On regression analysis, race emerged as a significant predictor of organ retrieval (p < 0.001). Medically suitable patients referred from the ED were significantly more likely on bivariate analysis to have consent for donation granted compared to patients referred from inpatient settings (OR = 1.48, 95% CI = 1.03 to 2.12), but this association was not found to be significant on regression analysis (OR = 1.37, 95% CI = 0.93 to 2.02).

CONCLUSIONS

Referral of potential organ donors from the ED is associated with an increased likelihood of successful organ retrieval. The authors conclude that further attention and resources should be directed toward the role of emergency medicine (EM) in the organ procurement process, owing to the relatively high likelihood of successful organ retrieval among patients referred from the ED.