Kidney Transplantation Contraindications: Variation in Nephrologist Practice and Training Vintage.

Introduction: Health system leaders aim to increase access to kidney transplantation in part by encouraging nephrologists to refer more patients for transplant evaluation. Little is known about nephrologists' referral decisions and whether nephrologists with older training vintage weigh patient criteria differently (e.g., more restrictively). Methods: Using a novel, iteratively validated survey of US-based nephrologists, we examined how nephrologists assess adult patients' suitability for transplant, focusing on established, important criteria: 7 clinical (e.g., overweight) and 7 psychosocial (e.g., insurance). We quantified variation in nephrologist restrictiveness-proportion of criteria interpreted as absolute or partial contraindications versus minor or negligible concerns-and tested associations between restrictiveness and nephrologist age (proxy for training vintage) in logistic regression models, controlling for nephrologist-level and practice-level factors. Results: Of 144 nephrologists invited, 42 survey respondents (29% response rate) were 85% male and 54% non-Hispanic White, with mean age 52 years, and 67% spent ≥1 day/wk in outpatient dialysis facilities. Nephrologists interpreted patient criteria inconsistently; consistency was lower for psychosocial criteria (intraclass correlation coefficient: 0.28) than for clinical criteria (intraclass correlation coefficient: 0.43; P < 0.01). With each additional 10 years of age, nephrologists' odds of interpreting criteria restrictively (top tertile) doubled (adjusted odds ratio [aOR] 1.96; 95% confidence interval [CI]: 0.95-4.07), with marginal statistical significance. This relationship was significant when interpreting psychosocial criteria (aOR: 3.18; 95% CI: 1.16-8.71) but not when interpreting clinical criteria (aOR: 1.12; 95% CI: 0.52-2.38). Conclusion: Nephrologists interpret evaluation criteria variably when assessing patient suitability for transplant. Guideline-based educational interventions could influence nephrologists' referral decision-making differentially by age.

Vaccination for Patients Receiving Dialysis.

Vaccinating patients receiving dialysis may prevent morbidity and mortality in this vulnerable population. The National Forum of End-Stage Renal Disease Networks (the Forum) published a revised vaccination toolkit in 2021 to update evidence and recommendations on vaccination for patients receiving dialysis. Significant changes in the last 10 years include more data supporting the use of a high-dose influenza vaccine, the introduction of the Heplisav-B vaccine for hepatitis B, and changes in pneumococcal vaccines, including the approval of the PCV15 and PCV20 to replace the PCV13 and PPSV23 vaccines. Additional key items include the introduction of vaccines against severe acute respiratory syndrome coronavirus 2, the virus that causes coronavirus disease 2019 (COVID-19), and a new vaccine to prevent respiratory syncytial virus disease. Historically, influenza and pneumococcal vaccinations were routinely administered by dialysis facilities, and because of possible risks of hematogenous spread of hepatitis B, dialysis providers often have detailed hepatitis B vaccine protocols. In March 2021, COVID-19 vaccines were made available for dialysis facilities to administer, although with the end of the public health emergency, vaccine policies by dialysis facilities against COVID-19 remains uncertain. The respiratory syncytial virus vaccine was authorized in 2023, and how dialysis facilities will approach this vaccine also remains uncertain. This review summarizes the Forum's vaccination toolkit and discusses the role of the dialysis facility in vaccinating patients to reduce the risk of severe infections.

Implementation of the ASCENT Trial to Improve Transplant Waitlisting Access.

Introduction: The Allocation System for changes in Equity in Kidney Transplantation (ASCENT) study was a hybrid type 1 trial of a multicomponent intervention among 655 US dialysis facilities with low kidney transplant waitlisting to educate staff and patients about kidney allocation system (KAS) changes and increase access to and reduce racial disparities in waitlisting. Intervention components included a staff webinar, patient and staff educational videos, and facility-specific feedback reports. Methods: Implementation outcomes were assessed using the Reach, Effectiveness, Adoption, Implementation, and Maintenance Framework. Postimplementation surveys were administered among intervention group facilities (n = 334); interviews were conducted with facility staff (n = 6). High implementation was defined as using 3 to 4 intervention components, low implementation as using 1 to 2 components, and nonimplementation as using no components. Results: A total of 331 (99%) facilities completed the survey; 57% were high implementers, 31% were low implementers, and 12% were nonimplementers. Waitlisting events were higher or similar among high versus low implementer facilities for incident and prevalent populations; for Black incident patients, the mean proportion waitlisted in low implementer facilities was 0.80% (95% confidence interval [CI]: 0.73-0.87) at baseline and 0.55% at 1-year (95% CI: 0.48-0.62) versus 0.83% (95% CI: 0.78-0.88) at baseline and 1.40% at 1-year (95% CI: 1.35-1.45) in high implementer facilities. Interviews revealed that the intervention helped facilities prioritize transplant education, but that intervention components were not uniformly shared. Conclusion: The findings provide important context to interpret ASCENT effectiveness results and identified key barriers and facilitators to consider for future modification and scale-up of multilevel, multicomponent interventions in dialysis settings.

Understanding Delayed Graft Function to Improve Organ Utilization and Patient Outcomes: Report of a Scientific Workshop Sponsored by the National Kidney Foundation.

Delayed graft function (DGF) is a common complication after kidney transplant. Despite extensive literature on the topic, the extant definition of DGF has not been conducive to advancing the scientific understanding of the influences and mechanisms contributing to its onset, duration, resolution, or long-term prognostic implications. In 2022, the National Kidney Foundation sponsored a multidisciplinary scientific workshop to comprehensively review the current state of knowledge about the diagnosis, therapy, and management of DGF and conducted a survey of relevant stakeholders on topics of clinical and regulatory interest. In this Special Report, we propose and defend a novel taxonomy for the clinical and research definitions of DGF, address key regulatory and clinical practice issues surrounding DGF, review the current state of therapies to reduce and/or attenuate DGF, offer considerations for clinical practice related to the outpatient management of DGF, and outline a prospective research and policy agenda.

Referral and evaluation for kidney transplantation among patients with lupus nephritis-related end-stage kidney disease.

OBJECTIVE: For the majority of patients with lupus nephritis-related end-stage kidney disease (LN-ESKD), kidney transplant is associated with better outcomes than dialysis. Access to kidney transplant requires an initial referral to a transplant center and medical evaluation prior to waitlisting. The study's objective was to examine access to these early steps in the kidney transplant process among patients with LN-ESKD. METHODS: Adults who began treatment for ESKD in the Southeast, Northeast, New York, or Ohio River Valley U.S. regions from 1/1/2012 to 12/31/2019, followed through 6/30/2021, were identified from the United States Renal Data System. Referral and evaluation start data were collected from 28 of 48 transplant centers across these regions. The exposure was primary cause of ESKD (LN-ESKD vs other-ESKD). The outcomes were referral and evaluation start at a transplant center. Cox models quantified the association between LN-ESKD (vs other-ESKD) and referral and evaluation start. RESULTS: Among 192,318 patients initiating treatment for ESKD, 0.4% had LN-ESKD. Over half (58%) of LN-ESKD patients were referred before study end, and among those referred, 66% started the evaluation. In adjusted analyses, patients with LN-ESKD were referred (HR: 1.09, 95% CI: 0.99, 1.19) and started the transplant evaluation (HR: 1.13, 95% CI: 1.00, 1.28) at a higher rate than patients with other-ESKD. Among referred patients with LN-ESKD, the median time from ESKD start to referral was 2.9 months (IQR: <1 to 11.7 months), which is similar to patients with other-ESKD (median 2.6 months, IQR: <1 to 8.8 months). CONCLUSIONS: Among incident patients with ESKD, having a primary diagnosis of LN-ESKD versus other-ESKD is associated with higher rates of early transplant access outcomes. Despite this, patients with LN-ESKD (vs other-ESKD) are less likely to be preemptively referred (i.e., referred prior to ESKD start) for kidney transplant. While providers may no longer be delaying the early steps in the kidney transplantation process among this patient population, there is still room for improvement in the rates of preemptive referral. Access to kidney transplant referral prior to ESKD could result in increased transplant rates and better transplant outcomes for patients with LN-ESKD.

Sex/Gender-Based Disparities in Early Transplant Access by Attributed Cause of Kidney Disease-Evidence from a Multiregional Cohort in the Southeast United States.

Introduction: We examined sex/gender disparities across the continuum of transplant care by attributed cause of end-stage kidney disease (ESKD). Methods: All adults (18-79 years; N = 43,548) with new-onset ESKD in Georgia, North Carolina, or South Carolina between 2015 and 2019 were identified from the United States Renal Data System (USRDS). Individuals were linked to the Early Steps to Transplant Access Registry (E-STAR) to obtain data on referral and evaluation. Waitlisting data was ascertained from USRDS. Using a Cox-proportional hazards model, with follow-up through 2020, we assessed the association between sex/gender and referral within 12 months (among all incident dialysis patients), evaluation start within 6 months (among referred patients), and waitlisting (among all evaluated patients) by attributed cause of ESKD (type 1 diabetes mellitus, type 2 diabetes mellitus, hypertension, glomerulonephritis, cystic disease, and other). Results: Overall, women (vs. men) with type 2 diabetes-attributed ESKD were 13% (crude hazard ratio [HR]: 0.87 [0.83-0.91]), 14% (crude HR: 0.86 [0.81-0.91]), and 14% (crude HR: 0.86 [0.78-0.94]) less likely to be referred, evaluated, and waitlisted, respectively. Women (vs. men) with hypertension-attributed ESKD were 14% (crude HR: 0.86 [0.82-0.90]) and 8% (crude HR: 0.92 [0.87-0.98]) less likely to be referred and evaluated, respectively, but similarly likely to be waitlisted once evaluated (crude HR: 1.06 [0.97-1.15]). For all other attributed causes of ESKD, there was no sex/gender disparity in referral, evaluation, or waitlisting rates. Conclusion: In the Southeast United States, sex/gender disparities in early access to kidney transplantation are specific to people with ESKD attributed to type 2 diabetes and hypertension.

Race, Age, and Kidney Transplant Waitlisting Among Patients Receiving Incident Dialysis in the United States.

Rationale & Objective: Patients with kidney failure from racial and ethnic minority groups and older patients have reduced access to the transplant waitlist relative to White and younger patients. Although racial disparities in the waitlisting group have declined after the 2014 kidney allocation system change, whether there is intersectionality of race and age in waitlisting access is unknown. Study Design: Retrospective cohort study. Setting & Participants: 439,455 non-Hispanic White and non-Hispanic Black US adults initiating dialysis between 2015 and 2019 were identified from the United States Renal Data System, and followed through 2020. Exposures: Patient race and ethnicity (non-Hispanic White and non-Hispanic Black) and age group (18-29, 30-49, 50-64, and 65-80 years). Outcomes: Placement on the United Network for Organ Sharing deceased donor waitlist. Analytical Approach: Age- and race-stratified waitlisting rates were compared. Multivariable Cox proportional hazards models, censored for death, examined the association between race and waitlisting, and included interaction term for race and age. Results: Over a median follow-up period of 1 year, the proportion of non-Hispanic White and non-Hispanic Black patients waitlisted was 20.7% and 20.5%, respectively. In multivariable models, non-Hispanic Black patients were 14% less likely to be waitlisted (aHR, 0.86, 95% CI, 0.77-0.95). Relative differences between non-Hispanic Black and non-Hispanic White patients were different by age group. Non-Hispanic Black patients were 27%, 12%, and 20% less likely to be waitlisted than non-Hispanic White patients for ages 18-29 years (aHR, 0.73; 95% CI, 0.61-0.86), 50-64 (aHR, 0.88; 95% CI, 0.80-0.98), and 65-80 years (aHR, 0.80; 95% CI, 0.71-0.90), respectively, but differences were attenuated among patients aged 30-49 years (aHR, 0.89; 95% CI, 0.77-1.02). Limitations: Race and ethnicity data is physician reported, residual confounding, and analysis is limited to non-Hispanic White and non-Hispanic Black patients. Conclusions: Racial disparities in waitlisting exist between non-Hispanic Black and non-Hispanic White individuals and are most pronounced among younger patients with kidney failure. Results suggest that interventions to address inequalities in waitlisting may need to be targeted to younger patients with kidney failure. Plain-Language Summary: Research has shown that patients from racial and ethnic minority groups and older patients have reduced access to transplant waitlisting relative to White and younger patients; nevertheless, how age impacts racial disparities in waitlisting is unknown. We compared waitlisting between non-Hispanic Black and non-Hispanic White patients with incident kidney failure, within age strata, using registry data for 439,455 US adults starting dialysis (18-80 years) during 2015-2019. Overall, non-Hispanic Black patients were less likely to be waitlisted and relative differences between the two racial groups differed by age. After adjusting for patient-level factors, the largest disparity in waitlisting was observed among adults aged 18-29 years. These results suggest that interventions should target younger adults to reduce disparities in access to kidney transplant waitlisting.

The ASCENT Intervention to Improve Access and Reduce Racial Inequalities in Kidney Waitlisting: A Randomized, Effectiveness-Implementation Trial.

BACKGROUND: The US kidney allocation system (KAS) changed in 2014, but dialysis facility staff (including nephrologists, social workers, nurse managers, and facility administrators) had low awareness of how this policy change could affect their patients' access to transplant. We assessed the effectiveness of a multicomponent and multilevel educational and outreach intervention targeting US dialysis facilities with low waitlisting, with a goal of increasing waitlisting and reducing Black versus White racial disparities in waitlisting. METHODS: The Allocation System Changes for Equity in Kidney Transplantation (ASCENT) study was a cluster-randomized, pragmatic, multilevel, effectiveness-implementation trial including 655 US dialysis facilities with low waitlisting, randomized to receive either the ASCENT intervention (a performance feedback report, a webinar, and staff and patient educational videos) or an educational brochure. Absolute and relative differences in coprimary outcomes (1-year waitlisting and racial differences in waitlisting) were reported among incident and prevalent patients. RESULTS: Among 56,332 prevalent patients, 1-year waitlisting decreased for patients in control facilities (2.72%-2.56%) and remained the same for patients in intervention facilities (2.68%-2.75%). However, the proportion of prevalent Black patients waitlisted in the ASCENT interventions increased from baseline to 1 year (2.52%-2.78%), whereas it remained the same for White patients in the ASCENT intervention facilities (2.66%-2.69%). Among incident patients in ASCENT facilities, 1-year waitlisting increased among Black patients (from 0.87% to 1.07%) but declined among White patients (from 1.54% to 1.27%). Significant racial disparities in waitlisting were observed at baseline, with incident Black patients in ASCENT facilities less likely to waitlist compared with White patients (adjusted odds ratio [aOR], 0.56; 95% confidence interval [CI], 0.35 to 0.92), but 1 year after the intervention, this racial disparity was attenuated (aOR, 0.84; 95% CI, 0.49 to 1.42). CONCLUSIONS: The ASCENT intervention may have a small effect on extending the reach of the new KAS policy by attenuating racial disparities in waitlisting among a population of US dialysis facilities with low waitlisting. CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER: National Institutes of Health ( NCT02879812 ). PODCAST: This article contains a podcast at https://dts.podtrac.com/redirect.mp3/www.asn-online.org/media/podcast/CJASN/2023_03_08_CJN09760822.mp3.

Treatment Patterns and Characteristics of Dialysis Facilities Randomly Assigned to the Medicare End-Stage Renal Disease Treatment Choices Model.

Importance: In 2021, Medicare launched the End-Stage Renal Disease Treatment Choices (ETC) model, which randomly assigned approximately 30% of dialysis facilities to new financial incentives to increase use of transplantation and home dialysis; these financial bonuses and penalties are calculated by comparing living-donor transplantation, transplant wait-listing, and home dialysis use in ETC-assigned facilities vs benchmarks from non-ETC-assigned (ie, control) facilities. Because model participation is randomly assigned, evaluators may attribute any downstream differences in outcomes to facility performance rather than any imbalance in baseline characteristics. Objective: To identify preintervention imbalances in dialysis facility characteristics that should be recognized in any ETC model evaluations. Design, Setting, and Participants: This cross-sectional study compared ETC-assigned and control dialysis facility characteristics in the United States from 2017 to 2018. A total of 6062 facilities were included. Data were analyzed from February 2021 to May 2022. Exposures: Assignment to the ETC model. Main Outcomes and Measures: Dialysis facilities' preintervention transplantations and home dialysis use, facility characteristics (notably, profit and chain status), patient demographic characteristics, and community socioeconomic characteristics. Results: Among 316 927 patients, with 6 178 855 attributed patient-months, the mean (SD) age in January 2017 was 59 (11) years, and 132 462 (42%) were female. Patients in ETC-assigned facilities had 9% (0.2 [95% CI, 0.1-0.2] percentage points) lower prevalence of living donor transplantation, 12% (3.2 [95% CI, 3.0-3.3] percentage points) lower prevalence of transplantation wait-listing, and 4% (0.4 [95% CI, 0.3-0.4] percentage points) lower prevalence of peritoneal dialysis use compared with control facilities. ETC-assigned facilities were 14% (5.1 [95% CI, 0.9-9.4] percentage points) more likely than control facilities to be owned by the second largest dialysis organization. Relative to control facilities, ETC-assigned facilities also treated 34% (6.6 [95% CI, 6.5-6.7] percentage point) fewer patients with Hispanic ethnicity and were located in communities with median household incomes that were 4% ($2500; 95% CI, $500-$4500) lower on average. Conclusions and Relevance: In this study, dialysis facilities in ETC-assigned regions had lower preintervention prevalence of transplantation wait-listing, living donor transplantation, and peritoneal dialysis use, relative to control facilities. ETC-assigned and control facilities also differed with respect to other facility, patient, and community characteristics. Evaluators should account for these preintervention imbalances to minimize bias in their inferences about the model's association with postintervention outcomes.

Gender Disparities in Kidney Transplantation Referral Vary by Age and Race: A Multiregional Cohort Study in the Southeast United States.

Introduction: Men (vs. women) are more likely to be waitlisted or receive a kidney transplant. Whether gender disparities exist in earlier transplant steps (i.e., referral) and whether age, race, or obesity factors play a role are unknown. Methods: Adults (18-80 years; N = 45,015) initiating dialysis in Georgia (GA), North Carolina (NC), or South Carolina (SC) (2012-2016) from the United States Renal Data System were linked to the Early Transplant Access Registry, with follow-up to December 2017. Using a mixed-effects logistic regression model adjusted for several patient characteristics, we assessed the association between gender and referral within 12 months, including interaction terms for age, race/ethnicity, and obesity. Results: Overall, 37.0% and 41.5% of women and men, respectively, were referred within 12 months. In fully adjusted models, women (vs. men) were 14% less likely to be referred (odds ratio [OR]: 0.86; 95% CI: 0.82-0.90). Women (vs. men) aged 45 to 64 years and 65 to 80 years were 0.93 (0.87-0.99) and 0.72 (0.66-0.77) less likely to be referred, respectively. Women (vs. men) of non-Hispanic White and non-Hispanic Black race were 0.76 (0.71-0.82) and 0.93 (0.88-0.99) less likely to be referred, respectively. For other race (Hispanic, other) and age (18-44 years) subgroups, and all obesity subgroups, no gender differences in referral rates were observed. Conclusion: In the Southeast, women are less likely to be referred for a transplant, and this disparity is specific to older non-Hispanic Black and White women. These findings have important implications for known gender disparities in upstream (i.e., waitlisting) transplant steps and in the design of interventions to reduce gender disparities in transplant.

Effect of pulmonary hypertension on 5-year outcome of kidney transplantation.

Pulmonary hypertension affects about one in four patients with advanced chronic kidney disease and significantly increases the risk of death. Kidney transplantation is the recommended management option for patients with progressive or end-stage kidney disease. However, the resource-limited nature of kidney transplantation and its intensive peri-operative and posttransplantation management motivates careful consideration of potential candidates' medical conditions to optimally utilize available graft organs. Since pulmonary hypertension is known to increase peri-operative morbidity and mortality among patients living with chronic kidney disease, we performed a retrospective cohort study to assess the impact of pretransplantation pulmonary hypertension on posttransplantation outcome. All patients who underwent single-organ kidney transplantation at our center in calendar years 2010 and 2011 were identified and the presence of pulmonary hypertension was determined from pretransplantation echocardiography. Outcome was assessed at 5 years following kidney transplantation. Of 350 patients who were included, 117 (33%) had evidence of pulmonary hypertension. The risk of death, graft dysfunction, or graft failure at 5 years after kidney transplantation was higher among those with pulmonary hypertension, primarily owing to an increased risk of graft dysfunction. Importantly, in this institutional cohort of kidney transplant recipients, pretransplant pulmonary hypertension was not associated with a difference in posttransplant survival at 5 years. While institutional and regional differences in outcome can be expected, this report suggests that carefully selected patients with pulmonary hypertension receive similar long-term benefits from kidney transplantation.

COVID-19 and transplantation-Data censoring.

During the early wave of the COVID-19 pandemic, the Scientific Registry of Transplant Recipients (SRTR) designated a "black out" period between March 12, 2020, and June 12, 2020, for transplant outcomes reporting. We discuss the implications and potential bias it has introduced as it may selectively favor the outcomes for certain regions and harm other regions due to varied effects of different waves of COVID-19 infections across the United States.

Referral and Evaluation for Kidney Transplantation Following Implementation of the 2014 National Kidney Allocation System.

RATIONALE & OBJECTIVE: The national kidney allocation system (KAS) implemented in December 2014 in the United States redefined the start of waiting time from the time of waitlisting to the time of kidney failure. Waitlisting has declined post-KAS, but it is unknown if this is due to transplant center practices or changes in dialysis facility referral and evaluation. The purpose of this study was to assess the impact of the 2014 KAS policy change on referral and evaluation for transplantation among a population of incident and prevalent patients with kidney failure. STUDY DESIGN: Cohort study. SETTING & PARTICIPANTS: 37,676 incident (2012-2016) patients in Georgia, North Carolina, and South Carolina identified within the US Renal Data System at 9 transplant centers and followed through December 2017. A prevalent population of 6,079 patients from the same centers receiving maintenance dialysis in 2012 but not referred for transplantation in 2012. EXPOSURE: KAS era (pre-KAS vs post-KAS). OUTCOME: Referral for transplantation, start of transplant evaluation, and waitlisting. ANALYTICAL APPROACH: Multivariable time-dependent Cox models for the incident and prevalent population. RESULTS: Among incident patients, KAS was associated with increased referrals (adjusted HR, 1.16 [95% CI, 1.12-1.20]) and evaluation starts among those referred (adjusted HR, 1.16 [95% CI, 1.10-1.21]), decreased overall waitlisting (adjusted HR, 0.70 [95% CI, 0.65-0.76]), and lower rates of active waitlisting among those evaluated compared to the pre-KAS era (adjusted HR, 0.81 [95% CI, 0.74-0.90]). Among the prevalent population, KAS was associated with increases in overall waitlisting (adjusted HR, 1.74 [95% CI, 1.15-2.63]) and active waitlisting among those evaluated (adjusted HR, 2.01 [95% CI, 1.16-3.49]), but had no significant impact on referral or evaluation starts among those referred. LIMITATIONS: Limited to 3 states, residual confounding. CONCLUSIONS: In the southeastern United States, the impact of KAS on steps to transplantation was different among incident and prevalent patients with kidney failure. Dialysis facilities referred more incident patients and transplant centers evaluated more incident patients after implementation of KAS, but fewer evaluated patients were placed onto the waitlist. Changes in dialysis facility and transplant center behaviors after KAS implementation may have influenced the observed changes in access to transplantation.

A Population Health Approach to Transplant Access: Challenging the Status Quo.

Transplant referral and evaluation are critical steps to waitlisting yet remain an elusive part of the transplant process. Despite calls for more data collection on pre-waitlisting steps, there are currently no national surveillance data to aid in understanding the causes and potential solutions for the extreme variation in access to transplantation. As population health scientists, epidemiologists, clinicians, and ethicists we submit that the transplant community has an obligation to better understand disparities in transplant access as a first necessary step to effectively mitigating these inequities. Our position is grounded in a population health approach, consistent with several new overarching national policy and quality initiatives. The purpose of this Perspective is to (1) provide an overview of how a population health approach should inform current multisystem policies impacting kidney transplantation and demonstrate how these efforts could be enhanced with national data collection on pre-waitlisting steps; (2) demonstrate the feasibility and concrete next steps for pre-waitlisting data collection; and (3) identify potential opportunities to use these data to implement effective population-level interventions, policies, and quality measures to improve equity in access to kidney transplantation.

Employment status at transplant influences ethnic disparities in outcomes after deceased donor kidney transplantation.

BACKGROUND: African American (AA) recipients of deceased-donor (DD) kidney transplants (KT) have shorter allograft survival than recipients of other ethnic groups. Reasons for this disparity encompass complex interactions between donors and recipients characteristics. METHODS: Outcomes from 3872 AA and 19,719 European American (EA) DDs who had one kidney transplanted in an AA recipient and one in an EA recipient were analyzed. Four donor/recipient pair groups (DRP) were studied, AA/AA, AA/EA, EA/AA, and EA/EA. Survival random forests and Cox proportional hazard models were fitted to rank and evaluate modifying effects of DRP on variables associated with allograft survival. These analyses sought to identify factors contributing to the observed disparities in transplant outcomes among AA and EA DDKT recipients. RESULTS: Transplant era, discharge serum creatinine, delayed graft function, and DRP were among the top predictors of allograft survival and mortality among DDKT recipients. Interaction effects between DRP with the kidney donor risk index and transplant era showed significant improvement in allograft survival over time in EA recipients. However, AA recipients appeared to have similar or poorer outcomes for DDKT performed after 2010 versus before 2001; allograft survival hazard ratios (95% CI) were 1.15 (0.74, 1.76) and 1.07 (0.8, 1.45) for AA/AA and EA/AA, compared to 0.62 (0.54, 0.71) and 0.5 (0.41, 0.62) for EA/EA and AA/EA DRP, respectively. Recipient mortality improved over time among all DRP, except unemployed AA/AAs. Relative to DDKT performed pre-2001, employed AA/AAs had HR = 0.37 (0.2, 0.69) versus 0.59 (0.31, 1.11) for unemployed AA/AA after 2010. CONCLUSION: Relative to DDKT performed before 2001, similar or worse overall DCAS was observed among AA/AAs, while EA/EAs experienced considerable improvement regardless of employment status, KDRI, and EPTS. AA recipients of an AA DDKT, especially if unemployed, had worse allograft survival and mortality and did not appear to benefit from advances in care over the past 20 years.