Association of Racial Disparities With Access to Kidney Transplant After the Implementation of the New Kidney Allocation System

Racial and ethnic disparities in post-liver transplant outcomes for patients with acute-on-chronic liver failure: An analysis of the UNOS database

BACKGROUND

The incidence of hospitalisations related to acute-on-chronic liver failure (ACLF) is increasing. Liver transplantation (LT) remains the definitive treatment for the condition.

AIM

To evaluate the influence of race and ethnicity on LT outcomes in ACLF.

METHODS

We conducted a retrospective analysis utilising LT data from the United Network for Organ Sharing (UNOS) database. White patients served as the control group and patients of other races were compared at each ACLF grade. The primary outcomes assessed were graft failure and all-cause mortality.

RESULTS

Blacks exhibited a higher all-cause mortality (Grade 1: aHR 1.36, 95% CI 1.18-1.57, p < 0.001; Grade 2: aHR 1.27, 95% CI 1.08-1.48, p = 0.003; Grade 3: aHR 1.19, 95% CI 1.04-1.37, p = 0.01) and graft failure (Grade 1: aHR 2.05, 95% CI 1.58-2.67, p < 0.001; Grade 2: aHR 1.91, 95% CI 1.43-2.54, p < 0.001; Grade 3: aHR 1.50, 95% CI 1.15-1.96, p = 0.002). Hispanics experienced a lower all-cause mortality at grades 1 and 3 (Grade 1: aHR 0.83, 95% CI 0.72-0.96, p = 0.01; Grade 3: aHR 0.80, 95% CI 0.70-0.91, p < 0.001) and Asians with severe ACLF demonstrated decreased all-cause mortality (Grade 3: aHR 0.55, 95% CI 0.42-0.73, p < 0.001).

CONCLUSION

Black patients experienced the poorest outcomes and Hispanic and Asian patients demonstrated more favourable outcomes compared to Whites.

Differences in Racial and Ethnic Disparities Between First and Repeat Kidney Transplantation

BACKGROUND

Recent data suggest patients with graft failure had better access to repeat kidney transplantation (re-KT) than transplant-naive dialysis accessing first KT. This was postulated to be because of better familiarity with the transplant process and healthcare system; whether this advantage is equitably distributed is not known. We compared the magnitude of racial/ethnic disparities in access to re-KT versus first KT.

METHODS

Using United States Renal Data System, we identified 104 454 White, Black, and Hispanic patients with a history of graft failure from 1995 to 2018, and 2 357 753 transplant-naive dialysis patients. We used adjusted Cox regression to estimate disparities in access to first and re-KT and whether the magnitude of these disparities differed between first and re-KT using a Wald test.

RESULTS

Black patients had inferior access to both waitlisting and receiving first KT and re-KT. However, the racial/ethnic disparities in waitlisting for (adjusted hazard ratio [aHR] = 0.77; 95% confidence interval [CI], 0.74-0.80) and receiving re-KT (aHR = 0.61; 95% CI, 0.58-0.64) was greater than the racial/ethnic disparities in first KT (waitlisting: aHR = 0.91; 95% CI, 0.90-0.93; Pinteraction  = 0.001; KT: aHR = 0.68; 95% CI, 0.64-0.72; Pinteraction < 0.001). For Hispanic patients, ethnic disparities in waitlisting for re-KT (aHR = 0.83; 95% CI, 0.79-0.88) were greater than for first KT (aHR = 1.14; 95% CI, 1.11-1.16; Pinteraction  < 0.001). However, the disparity in receiving re-KT (aHR = 0.76; 95% CI, 0.72-0.80) was similar to that for first KT (aHR = 0.73; 95% CI, 0.68-0.79; Pinteraction  = 0.55). Inferences were similar when restricting the cohorts to the Kidney Allocation System era.

CONCLUSIONS

Unlike White patients, Black and Hispanic patients with graft failure do not experience improved access to re-KT. This suggests that structural and systemic barriers likely persist for racialized patients accessing re-KT, and systemic changes are needed to achieve transplant equity.

Socioeconomic disparities in kidney transplant access for patients with end-stage kidney disease within the All of Us Research Program

OBJECTIVES

Disparity in kidney transplant access has been demonstrated by a disproportionately low rate of kidney transplantation in socioeconomically disadvantaged patients. However, the information is not from national representative populations with end-stage kidney disease (ESKD). We aim to examine whether socioeconomic disparity for kidney transplant access exists by utilizing data from the All of Us Research Program.

MATERIALS AND METHODS

We analyzed data of adult ESKD patients using the All of Us Researcher Workbench. The association of socioeconomic data including types of health insurance, levels of education, and household incomes with kidney transplant access was evaluated by multivariable logistic regression analysis adjusted by baseline demographic, medical comorbidities, and behavioral information.

RESULTS

Among 4078 adults with ESKD, mean diagnosis age was 54 and 51.64% were male. The majority had Medicare (39.6%), were non-graduate college (75.79%), and earned $10 000-24 999 annual income (20.16%). After adjusting for potential confounders, insurance status emerged as a significant predictor of kidney transplant access. Individuals covered by Medicaid (adjusted odds ratio [AOR] 0.45; 95% confidence interval [CI], 0.35-0.58; P-value < .001) or uninsured (AOR 0.21; 95% CI, 0.12-0.37; P-value < .001) exhibited lower odds of transplantation compared to those with private insurance.

DISCUSSION/CONCLUSION

Our findings reveal the influence of insurance status and socioeconomic factors on access to kidney transplantation among ESKD patients. Addressing these disparities through expanded insurance coverage and improved healthcare access is vital for promoting equitable treatment and enhancing health outcomes in vulnerable populations.

Regional Disparities in Kidney Transplant Allocation in Brazil: A Retrospective Cohort Study

BACKGROUND

Brazil has a large public transplant program, but it remains unclear if the kidney waitlist criteria effectively allocate organs. This study aimed to investigate whether gender, ethnicity, clinical characteristics, and Brazilian regions affect the chance of deceased donor kidney transplant (DDKT).

METHODS

We conducted a retrospective cohort study using the National Transplant System/Brazil database, which included all patients on the kidney transplant waitlist from January 2012 to December 2022, followed until May 2023. The primary outcome assessed was the chance of DDKT, measured using subdistribution hazard and cause-specific hazard models (subdistribution hazard ratio [sHR]).

RESULTS

We analyzed 118 617 waitlisted patients over a 10-year study period. Male patients had an sHR of 1.07 ([95% CI: 1.05-1.10], p < 0.001), indicating a higher chance of DDTK. Patients of mixed race and Yellow/Indigenous ethnicity had lower rates of receiving a transplant compared to Caucasian patients, with sHR of 0.97 (95% CI: 0.95-1) and 0.89 (95% CI: 0.95-1), respectively. Patients from the South region had the highest chance of DDKT, followed by those from the Midwest and Northeast, compared to patients from the Southeast, with sHR of 2.53 (95% CI: 2.47-2.61), 1.21 (95% CI: 1.16-1.27), and 1.10 (95% CI: 1.07-1.13), respectively. The North region had the lowest chance of DDTK, sHR of 0.29 (95% CI: 0.27-0.31).

CONCLUSION

We found that women and racial minorities faced disadvantages in kidney transplantation. Additionally, we observed regional disparities, with the North region having the lowest chance of DDKT and longer times on dialysis before being waitlisted. In contrast, patients in the South regions had a chance of DDKT and shorter times on dialysis before being waitlisted. It is urgent to implement approaches to enhance transplant capacity in the North region and address race and gender disparities in transplantation.

Highly Sensitized Kidney Transplant Outcomes After the 2014 Kidney Allocation System Change

Introduction: Kidney Allocation System (KAS) was implemented by United Network for Organ Sharing in 2014 to reduce allocation disparities. Research Questions: Outcomes of highly sensitized patients (calculated panel reactive antibody (cPRA) ≥ 97%) before and after KAS were compared to low-risk recipients (cPRA <10%) in the post-KAS era were examined. The impact on racial disparities was determined. Design: This was a retrospective study of national registry data. Two cohorts of adult candidates waitlisted for deceased donor transplantation during 3-year periods before and after KAS were identified. Results: Highly sensitized patients (N = 1238 and 4687) received a deceased donor kidney transplant between January 1, 2011 and December 31, 2013 and between January 1, 2015 and December, 31, 2017. Racial disparity for highly sensitized patients improved, yet remained significant (P < 0.001), with Black patients comprising 40% and 41% of the highly sensitized candidates and 28% and 34% of the recipients pre- and post-KAS. While posttransplant death-censored graft failure for highly sensitized recipients was similar overall, post-KAS was associated with improved graft survival in the first year after transplant (HR 0.56, 95% CI 0.40-0.78). When compared to contemporaneous lowrisk recipients, both death-censored and all-cause graft failure were similar for highly sensitized recipients and was associated with increased risk for death-censored graft failure beyond the first year (HR 1.39, 95% CI 1.11-1.73). Conclusion: The allocation system led to an increase in transplantation in highly sensitized candidates without compromising outcomes. Although KAS has led to more balanced transplant rates between highly sensitized Black and White patients, racial inequalities persist.

Care of Adults with Advanced Chronic Kidney Disease

Chronic kidney disease (CKD) impacts over 10% of the global population. Adults with CKD face significant morbidity and mortality. As kidney disease progresses, the risk of adverse outcomes increases. Here, we present an overview of strategies to care for adults with advanced CKD (stage 4-5 CKD, not receiving kidney replacement therapy). We aim to guide clinicians through several aspects of CKD care, ranging from recommended laboratory assessments to interdisciplinary support for patients as they plan for kidney replacement therapy (dialysis, transplantation, or conservative management). We incorporate considerations of health equity and person-centered care, empowering clinicians to deliver high-quality care to people with CKD.

Comparison Between Black Non-Hispanic and White Non-Hispanic Simultaneous Pancreas-Kidney Transplant Candidates and Recipients

INTRODUCTION

This study examined simultaneous pancreas-kidney transplant (SPKt) in Black and White patients to identify disparities in transplantation, days on the waitlist, and reasons for SPKt waitlist removal.

METHODS

Using the United Network for Organ Sharing Standard Transplant Analysis and Research file, patients between January 1, 2009, and May 31, 2021, were included. Three cohorts (overall, SPKt recipients only, and those not transplanted) were selected using propensity score matching. Conditional logistic regression was used for categorical outcomes. Days on the waitlist were compared using negative binomial regression.

RESULTS

Black patients had increased odds of receiving a  SPKt (OR, 1.25 [95% CI, 1.11-1.40], p < 0.001). White patients had increased odds of receiving a kidney-only transplant (OR 0.48 [95% CI, 0.38-0.61], p < 0.001), and specifically increased odds of receiving a living donor kidney (OR 0.34 [0.25-0.45], p < 0.001).

CONCLUSION

This study found that Black patients are more likely to receive a SPKt. Results suggest that there are opportunities for additional inquiry related to patient removal from the waitlist, particularly considering White patients received or accepted more kidney-only transplants and were more likely to receive a living donor kidney-only transplant.

Evaluating site-of-care-related racial disparities in kidney graft failure using a novel federated learning framework

OBJECTIVES

Racial disparities in kidney transplant access and posttransplant outcomes exist between non-Hispanic Black (NHB) and non-Hispanic White (NHW) patients in the United States, with the site of care being a key contributor. Using multi-site data to examine the effect of site of care on racial disparities, the key challenge is the dilemma in sharing patient-level data due to regulations for protecting patients' privacy.

MATERIALS AND METHODS

We developed a federated learning framework, named dGEM-disparity (decentralized algorithm for Generalized linear mixed Effect Model for disparity quantification). Consisting of 2 modules, dGEM-disparity first provides accurately estimated common effects and calibrated hospital-specific effects by requiring only aggregated data from each center and then adopts a counterfactual modeling approach to assess whether the graft failure rates differ if NHB patients had been admitted at transplant centers in the same distribution as NHW patients were admitted.

RESULTS

Utilizing United States Renal Data System data from 39 043 adult patients across 73 transplant centers over 10 years, we found that if NHB patients had followed the distribution of NHW patients in admissions, there would be 38 fewer deaths or graft failures per 10 000 NHB patients (95% CI, 35-40) within 1 year of receiving a kidney transplant on average.

DISCUSSION

The proposed framework facilitates efficient collaborations in clinical research networks. Additionally, the framework, by using counterfactual modeling to calculate the event rate, allows us to investigate contributions to racial disparities that may occur at the level of site of care.

CONCLUSIONS

Our framework is broadly applicable to other decentralized datasets and disparities research related to differential access to care. Ultimately, our proposed framework will advance equity in human health by identifying and addressing hospital-level racial disparities.

Xenotransplantation could either be a friend or foe of healthcare equity

Chisholm-Burns et al. discuss the substantial shortage of organs available for transplantation, with disparities in access amongst some racial and ethnic groups. The authors suggest that while xenotransplantation can potentially increase organ availability, it also has the potential to further embed inequities in transplant care.

Characteristics and Outcomes of Patients With Pregnancy-Related End-Stage Kidney Disease

Importance

The incidence of pregnancy-related acute kidney injury is increasing and is associated with significant maternal morbidity including progression to end-stage kidney disease (ESKD). Little is known about characteristics and long-term outcomes of patients who develop pregnancy-related ESKD.

Objectives

To examine the characteristics and clinical outcomes of patients with pregnancy-related ESKD and to investigate associations between pre-ESKD nephrology care and outcomes.

Design, Setting, and Participants

This was a cohort study of 183 640 reproductive-aged women with incident ESKD between January 1, 2000, and November 20, 2020, from the US Renal Data System and maternal data from births captured in the US Centers for Disease Control and Prevention publicly available natality data. Data were analyzed from December 2022 to June 2023.

Exposure

Pregnancy-related primary cause of ESKD, per International Classification of Diseases, Ninth Revision (ICD-9) and ICD-10 codes reported at ESKD onset by the primary nephrologist on Centers for Medicare and Medicaid Services form 2728.

Main Outcomes Measures

Multivariable Cox proportional hazards and competing risk models were constructed to examine time to (1) mortality, (2) access to kidney transplant (joining the waiting list or receiving a live donor transplant), and (3) receipt of transplant after joining the waitlist.

Results

A total of 341 patients with a pregnancy-related primary cause of ESKD were identified (mean [SD] age 30.2 [7.3]). Compared with the general US birthing population, Black patients were overrepresented among those with pregnancy-related ESKD (109 patients [31.9%] vs 585 268 patients [16.2%]). In adjusted analyses, patients with pregnancy-related ESKD had similar or lower hazards of mortality compared with those with glomerulonephritis or cystic kidney disease (adjusted hazard ratio [aHR], 0.96; 95% CI, 0.76-1.19), diabetes or hypertension (aHR, 0.49; 95% CI, 0.39-0.61), or other or unknown primary causes of ESKD (aHR, 0.60; 95% CI, 0.48-0.75). Despite this, patients with pregnancy-related ESKD had significantly lower access to kidney transplant compared with those with other causes of ESKD, including (1) glomerulonephritis or cystic kidney disease (adjusted subhazard ratio [aSHR], 0.51; 95% CI, 0.43-0.66), (2) diabetes or hypertension (aSHR, 0.81; 95% CI, 0.67-0.98), and (3) other or unkown cause (aSHR, 0.82; 95% CI, 0.67-0.99). Those with pregnancy-related ESKD were less likely to have nephrology care or have a graft or arteriovenous fistula placed before ESKD onset (nephrology care: adjusted relative risk [aRR], 0.47; 95% CI, 0.40-0.56; graft or arteriovenous fistula placed: aRR, 0.31; 95% CI, 0.17-0.57).

Conclusion and Relevance

In this study, those with pregnancy-related ESKD had reduced access to transplant and nephrology care, which could exacerbate existing disparities in a disproportionately Black population. Increased access to care could improve quality of life and health outcomes among these young adults with high potential for long-term survival.

Disparities in Kidney Transplant Waitlisting Among Young Patients Without Medical Comorbidities

Importance

Disparities in kidney transplant referral and waitlisting contribute to disparities in kidney disease outcomes. Whether these differences are rooted in population differences in comorbidity burden is unclear.

Objective

To examine whether disparities in kidney transplant waitlisting were present among a young, relatively healthy cohort of patients unlikely to have medical contraindications to kidney transplant.

Design, Setting, and Participants

This retrospective cohort study used the US Renal Data System Registry to identify patients with end-stage kidney disease who initiated dialysis between January 1, 2005, and December 31, 2019. Patients who were older than 40 years, received a preemptive transplant, were preemptively waitlisted, or had documented medical comorbidities other than hypertension or smoking were excluded, yielding an analytic cohort of 52 902 patients. Data were analyzed between March 1, 2022, and February 1, 2023.

Main Outcome(s) and Measure(s)

Kidney transplant waitlisting after dialysis initiation.

Results

Of 52 902 patients (mean [SD] age, 31 [5] years; 31 132 [59%] male; 3547 [7%] Asian/Pacific Islander, 20 782 [39%] Black/African American, and 28 006 [53%] White) included in the analysis, 15 840 (30%) were waitlisted for a kidney transplant within 1 year of dialysis initiation, 11 122 (21%) were waitlisted between 1 and 5 years after dialysis initiation, and 25 940 (49%) were not waitlisted by 5 years. Patients waitlisted within 1 year of dialysis initiation were more likely to be male, to be White, to be employed full time, and to have had predialysis nephrology care. There were large state-level differences in the proportion of patients waitlisted within 1 year (median, 33%; range, 15%-58%). In competing risk regression, female sex (adjusted subhazard ratio [SHR], 0.92; 95% CI, 0.90-0.94), Hispanic ethnicity (SHR, 0.77; 95% CI, 0.75-0.80), and Black race (SHR, 0.66; 95% CI, 0.64-0.68) were all associated with lower waitlisting after dialysis initiation. Unemployment (SHR, 0.47; 95% CI, 0.45-0.48) and part-time employment (SHR, 0.74; 95% CI, 0.70-0.77) were associated with lower waitlisting compared with full-time employment, and more than 1 year of predialysis nephrology care, compared with none, was associated with greater waitlisting (SHR, 1.51; 95% CI, 1.46-1.56).

Conclusions and Relevance

This retrospective cohort study found that fewer than one-third of patients without major medical comorbidities were waitlisted for a kidney transplant within 1 year of dialysis initiation, with sociodemographic disparities in waitlisting even in this cohort of young, relatively healthy patients unlikely to have a medical contraindication to transplantation. Transplant policy changes are needed to increase transparency and address structural barriers to waitlist access.

Breaking Barriers and Bridging Gaps: Advancing Diversity, Equity, and Inclusion in Kidney Transplant Care for Black and Hispanic Patients in the United States

Kidney transplantation offers better mortality and quality of life outcomes to patients with end-stage renal failure compared to dialysis. Specifically, living donor kidney transplantation is the best treatment for end-stage renal disease, since it offers the greatest survival benefit compared to deceased donor kidney transplant or dialysis. However, not all patients from all racial/ethnic backgrounds enjoy these benefits. While black and Hispanic patients bear the predominant disease burden within the United States, they represent less than half of all kidney transplants in the country. Other factors such as cultural barriers that proliferate myths about transplant, financial costs that impede altruistic donation, and even biological predispositions create a complex maze and can also perpetuate care inaccessibility. Therefore, blanket efforts to increase the overall donation pool may not extend access to vulnerable populations, who may require more targeted attention and interventions. This review uses US kidney transplantation data to substantiate accessibility differences amongst racial minorities as well as provides examples of successful institutional and national systemic level changes that have improved transplantation outcomes for all.

Factors associated with health inequities in access to kidney transplantation in the USA: A scoping review

BACKGROUND

The kidney is the most needed organ for transplantation in the United States. However, demand and scarcity of this organ has caused significant inequities for historically marginalized groups. In this review, we report on the frequency of inequities in all steps of kidney transplantation from 2016 to 2022. Search criteria was based on the National Institute of Health's (NIH) 2022 list of populations who experience health inequities, which includes: race and ethnicity; sex or gender; Lesbian, Gay, Bisexual, Transgender, Queer + (LGBTQ+); underserved rural communities; education level; income; and occupation status. We outline steps for future research aimed at assessing interventions and programs to improve health outcomes.

METHODS

This scoping review was developed following guidelines from the Joanna Briggs Institute and PRISMA extension for scoping reviews. In July 2022, we searched Medline (via PubMed) and Ovid Embase databases to identify articles addressing inequities in access to kidney transplantation in the United States. Articles had to address at least one of the NIH's 2022 health inequity groups.

RESULTS

Our sample of 44 studies indicate that Black race, female sex or gender, and low socioeconomic status are negatively associated with referral, evaluation, and waitlisting for kidney transplantation. Furthermore, only two studies from our sample investigated LGBTQ+ identity since the NIH's addition of SGM in 2016 regarding access to transplantation. Lastly, we found no detectable trend in studies for the four most investigated inequity groups between 2016 and 2022.

CONCLUSION

Investigations in inequities for access to kidney transplantation for the two most studied groups, race/ethnicity and sex or gender, have shown no change in frequencies. Regarding race and ethnicity, continued interventions focused on educating Black patients and staff of dialysis facilities may increase transplant rates. Studies aimed at assessing effectiveness of the Kidney Paired Donation program are highly warranted due to incompatibility problems in female patients. The sparse representation for the LGBTQ+ population may be due to a lack of standardized data collection for sexual orientation. We recommend this community be engaged via surveys and further investigations.

Racial and Ethnic Disparity in Prehospital Pain Management for Trauma Patients

BACKGROUND

Although evidence suggests that racial and ethnic minority (REM) patients receive inadequate pain management in the acute care setting, it remains unclear whether these disparities also occur during the prehospital period. The aim of this study is to assess the impact of race and ethnicity on prehospital analgesic use by emergency medical services (EMS) in trauma patients.

STUDY DESIGN

Retrospective chart review of adult trauma patients aged 18 to 89 years old transported by EMS to our American College of Surgeons-verified level 1 trauma center from 2014 to 2020. Patients who identified as Black, Asian, Native American, or Other for race and/or Hispanic or Latino or Unknown for ethnicity were considered REM. Patients who identified as White, non-Hispanic were considered White. Groups were compared in univariate and multivariate analysis. The primary outcome was prehospital analgesic administration.

RESULTS

A total of 2,476 patients were transported by EMS (47% White and 53% REM). White patients were older on average (46 years vs 38 years; p < 0.001) and had higher rates of blunt trauma (76% vs 60%; p < 0.001). There were no differences in Injury Severity Score (21 vs 20; p = 0.22). Although REM patients reported higher subjective pain rating (7.2 vs 6.6; p = 0.002), they were less likely to get prehospital pain medication (24% vs 35%; p < 0.001), and that difference remained significant after controlling for baseline characteristics, transport method, pain rating, prehospital hypotension, and payor status (adjusted odds ratio [95% CI], 0.67 [0.47 to 0.96]; p = 0.03).

CONCLUSIONS

Patients from racial and ethnic minority groups were less likely to receive prehospital pain medication after traumatic injury than White patients. Forms of conscious and unconscious bias contributing to this inequity need to be identified and addressed.

Does anybody really know what (the kidney median waiting) time is?

The median waiting time (MWT) to deceased donor kidney transplant is of interest to patients, clinicians, and the media but remains elusive due to both methodological and philosophical challenges. We used Organ Procurement and Transplantation Network data from January 2003 to March 2022 to estimate MWTs using various methods and timescales, applied overall, by era, and by candidate demographics. After rising for a decade, the overall MWT fell to 5.19 years between 2015 and 2018 and declined again to 4.05 years (April 2021 to March 2022), based on the Kaplan-Meier method applied to period-prevalent cohorts. MWTs differed markedly by blood type, donor service area, and pediatric vs adult status, but to a lesser degree by race/ethnicity. Choice of methodology affected the magnitude of these differences. Instead of waiting years for an answer, reliable kidney MWT estimates can be obtained shortly after a policy is implemented using the period-prevalent Kaplan-Meier approach, a theoretical but useful construct for which we found no evidence of bias compared with using incident cohorts. We recommend this method be used complementary to the competing risks approach, under which MWT is often inestimable, to fill the present information void concerning the seemingly simple question of how long it takes to get a kidney transplant in the United States.

United Network for Organ Sharing (UNOS) Database Analysis of Factors Associated With Kidney Transplant Time on Waiting List

INTRODUCTION

 In the United States (U.S.), African Americans and other minority groups have longer wait times for kidney transplantation than Caucasians. To date, many studies analyzing time spent on the waitlist for each race/ethnicity have been done. However, there are few to no studies examining waitlist time after the 2019 policy changes to the geographic distribution of donated kidneys.

METHODS

Data collected from the National Organ Procurement and Transplantation Network database were used to analyze associations between race and time spent on the waitlist for a kidney transplant in the U.S. Additional sub-categorical data were analyzed to determine further associations and potential covariates, such as gender, age, citizenship, primary source of payment, region of transplant center, BMI, Kidney Donor Profile Index (KDPI), renal diagnosis, and presence/type of diabetes. Data were analyzed using odds ratios and validated by Bonferroni-Holm's corrected chi-square tests at confidence intervals of 95% to determine if there are statistically significant differences between transplant time spent on the waitlist and ethnicity, as well as age, diagnosis category, region of transplant center, and KDPI.

RESULTS

Statistically significant increased odds of remaining on the transplant list at two years existed for all non-white races/ethnicities, except those identifying as multiracial. Asian American candidates had the greatest odds of remaining on the waitlist greater than two years in comparison to white candidates: 1.51 times that of a patient categorized as white (odds ratio [OR] 1.51, confidence interval [CI] 1.44-1.57). African American/Black, (OR 1.38, CI 1.34-1.43) Pacific Islander (OR 1.38, CI 1.17-1.63), Hispanic candidates (OR 1.37, CI 1.32-1.41), and American Indian or Native Alaskan candidates (OR 1.23, CI 1.12-1.46) also had increased odds of remaining on the transplant waitlist greater than two years compared to white candidates.

DISCUSSION

In this study, ethnic disparities persisted as a barrier for non-white individuals receiving treatment for end-stage kidney disease, specifically in the context of time spent on the waitlist for a kidney transplant. Further research is needed regarding the causes of these disparities in time spent on the waitlist, such as cultural restrictions in organ donation, racial differences in parameters for organ match, and institutionalized racism in health care practitioners.

Waiting-List and early posttransplant prognosis among ethnoracial groups: Data from the organ procurement and transplantation network

Background

Racial/ethnic disparity in waiting-list mortality among candidates listed for kidney transplantation (KT) in the United States remains unclear. We aimed to assess racial/ethnic disparity in waiting-list prognosis among patients listed for KT in the United States in the current era.

Methods

We compared waiting-list and early posttransplant in-hospital mortality or primary nonfunction (PNF) among adult (age ≥18 years) white, black, Hispanic, and Asian patients listed for only KT in the United States between July 1, 2004 and March 31, 2020.

Results

Of the 516,451 participants, 45.6%, 29.8%, 17.5%, and 7.1% were white, black, Hispanic, and Asian, respectively. Mortality on the 3-year waiting list (including patients who were removed for deterioration) was 23.2%, 16.6%, 16.2%, and 13.8% in white, black, Hispanic, and Asian patients, respectively. The cumulative incidence of posttransplant in-hospital death or PNF after KT was 3.3%, 2.5%, 2.4%, and 2.2% in black, white, Hispanic, and Asian patients,respectively. White candidates had the highest mortality risk on the waiting list or of becoming too sick for a transplant, while black (adjusted hazard ratio, [95% confidence interval, CI], 0.67 [0.66-0.68]), Hispanic (0.59 [0.58-0.60]), and Asian (0.54 [0.52-0.55]) candidates had a lower risk. Black KT recipients (odds ratio, [95% CI] 1.29 [1.21-1.38]) had a higher risk of PNF or death before discharge than white patients. After controlling confounders, black recipients (0.99 [0.92-1.07]) had a similar higher risk of posttransplant in-hospital mortality or PNF as white patients than Hispanic and Asian counterparts.

Conclusions

Despite having a better socioeconomic status and being allocated better kidneys, white patients had the worst prognosis during the waiting periods. Black recipients and white recipients have higher posttransplant in-hospital mortality or PNF.

Broad organ acceptance and equitable access to early kidney transplantation

BACKGROUND

Broad organ acceptance can increase early kidney transplantation (KTX) within <1-year of dialysis initiation while improving access inequity.

METHODS

Single-center data of adult isolated deceased-donor KTX recipients between 2013 and 2020 were stratified into three 2.5-year periods before-, early after-, and late after our center's deceased-donor organ acceptance practice change, excluding a 6-month implementation period. Outcomes were assessed within five recipient subgroups based on demographic and clinical characteristics.

RESULTS

Of 704 recipients, the frequency of early KTX was 22% pre-change, 36% early post-change, and 34% late post-change. Given similar post-change frequencies of early KTX, post-change eras were combined to improve analytic power of subgroup analyses. After the organ acceptance practice change (vs. pre-change), the likelihood of early KTX increased variably within historically underserved groups, including recipients who were older (37%-39%, p = .859), Black (10%-21%, p = .136), female (21%-37%, p = .034), diabetic (13%-32%, p = .010), and BMI≥35 kg/m² (20%-34%, p = .007). Despite the practice change, Black recipients continued to experience less early KTX compared to non-Black recipients. The likelihood of delayed graft function was significantly increased (p < .001), and 1-year creatinine was significantly higher (p < .001) post-practice change, but between-era risk-adjusted death-censored graft survival was similar.

CONCLUSIONS

Transition to broader donor acceptance was associated with more early KTXs among historically underserved patient subgroups. However, the effect was non-significant among Black recipients, suggesting the need for additional strategies to impact early transplant access for this population. Studies of broad organ acceptance are needed to examine both access and outcomes.

Information design to support growth, quality, and equity of the US transplant system

The Organ Procurement and Transplantation Network, an arm of the Health Resources and Services Administration, has a contract with the United Network for Organ Sharing since 1986 to provide central oversight of organ donation and transplants in the United States. The United Network for Organ Sharing has recently come under scrutiny, prompting a review by the National Academies of Sciences, Engineering, and Medicine as summarized in its recent report and also by the US Senate Finance Committee. The national news services have opined about organ donation ethics, access to transplantation particularly for medically underserved populations, and management of organ transplantation data. These critiques raise important concerns that deserve our best response as a transplant community. Broadly, we suggest that the data management approach of the Organ Procurement and Transplantation Network be replaced with a patient-centric omnichannel network in which all donor and recipient data exist in a single longitudinal record that can be used by all applications. A more comprehensive and standardized approach to donor data collection would drive quality improvement across organ procurement organizations and help address inequities in transplantation. Finally, a substantial increase in organ donation would be prompted by considering organ donors as a public health resource, meriting transparent publicly available data collection with respect to organ donor referral, screening, and management.

A qualitative systematic review of anonymous/unspecified living kidney and liver donors' perspectives

OBJECTIVES & BACKGROUND

Anonymous live organ donors or unspecified donors are individuals willing to be organ donors for any transplant recipient with whom they have no biological or antecedent emotional relationship. Despite excellent recipient outcomes and the potential to help address organ scarcity, controversy surrounds the unconditional act of gifting one's organs to an unrelated recipient. This qualitative systematic review provides insights into the first-hand experiences, motivations, and challenges that unspecified donors face.

METHODS

A systematic search was conducted on Medline, Embase, CINAHL, PsycINFO, and Web of Science database for qualitative literature regarding unspecified living donors' motivations and experiences in liver and kidney transplantation. An inductive thematic analysis was conducted to generate themes and supportive subthemes.

RESULTS

12 studies were included. The four major themes were (i) motivations, (ii) perception of risks, (iii) donor support, and (iv) benefits of donation. Unspecified donors demonstrated a deep sense of social responsibility but tended to underestimate health risks in favour of benefits for recipients. Despite the lack of emotional support from family and friends, the decision to donate was a resolute personal decision for donors. Majority benefitted emotionally and did not express regret.

CONCLUSION

This qualitative review bridges the gap in literature on unspecified living donor psychology and provides a comprehensive understanding of the decision-making matrix and experiences of donors.

Protocol for the AKT-MP trial: Access to Kidney Transplantation in Minority Populations

Background

Kidney transplant (KT) is the optimal treatment for kidney failure (KF), and although completion of KT evaluation is an essential step in gaining access to transplantation, the process is lengthy, time consuming, and burdensome. Furthermore, despite similar referral rates to non-Hispanic Whites, both Hispanic/Latinos and American Indians are less likely to be wait-listed or to undergo KT.

Methods

The Access to Kidney Transplantation in Minority Populations (AKT-MP) Trial compares two patient-centered methods to facilitate KT evaluation: kidney transplant fast track (KTFT), a streamlined KT evaluation process; and peer navigators (PN), a peer-assisted evaluation program that incorporates motivational interviewing. This pragmatic randomized trial will use a comparative effectiveness approach to assess whether KTFT or PN can help patients overcome barriers to transplant listing. We will randomly assign patients to the two conditions. We will track participants' medical records and conduct surveys prior to their initial evaluation clinic visit and again after they complete or discontinue evaluation.

Conclusion

Our aims are to (1) compare KTFT and PN to assess improvements in kidney transplant (KT) related outcomes and cost effectiveness; (2) examine how each approach effects changes in cultural/contextual factors, KT concerns, KT knowledge, and KT ambivalence; and (3) develop a framework for widespread implementation of either approach. The results of this trial will provide key information for facilitating the evaluation process, improving patient care, and decreasing disparities in KT.

ABO-adjusted calculated panel reactive antibody (cPRA): A unified metric for immunologic compatibility in kidney transplantation

Implementation of the kidney allocation system in 2014 greatly reduced access disparity due to human leukocyte antigen (HLA) sensitization. To address persistent disparity related to candidate ABO blood groups, herein we propose a novel metric termed "ABO-adjusted cPRA," which simultaneously considers the impact of candidate HLA and ABO sensitization on the same scale. An ethnic-weighted ABO-adjusted cPRA value was computed for 190 467 candidates on the kidney waitlist by combining candidate's conventional HLA cPRA with the remaining fraction of HLA-compatible donors that are ABO-incompatible. Consideration of ABO sensitization resulted in higher ABO-adjusted cPRA relative to conventional cPRA by HLA alone, except for AB candidates since they are not ABO-sensitized. Within cPRA Point Group = 99%, 43% of the candidates moved up to ABO-adjusted cPRA Point Group = 100%, though this proportion varied substantially by candidate blood group. Nearly all O and most B candidates would have elevated ABO-adjusted cPRA values above this policy threshold for allocation priority, but relatively few A candidates displayed this shift. Overall, ABO-adjusted cPRA more accurately measures the proportion of immune-compatible donors compared with conventional HLA cPRA, especially for highly sensitized candidates. Implementation of this novel metric could enable the development of allocation policies permitting more ABO-compatible transplants without compromising equity.

Defining the ethical considerations surrounding kidney transplantation for frail and cognitively impaired patients: a Delphi study of geriatric transplant experts

Background

Among adult kidney transplant (KT) candidates, 21% are frail and 55% have cognitive impairment, increasing the risk of pre- and post-KT mortality. Centers often assess frailty status and cognitive function during transplant evaluation to help identify appropriate candidate. Yet, there are no ethical guidelines regarding the use of frailty and cognitive function during this evaluation. We seek to develop a clinical consensus on balancing utility and justice in access to KT for frail and cognitively impaired patients.

Methods

Twenty-seven experts caring for ESRD patients completed a two-round Delphi panel designed to facilitate consensus (> 80% agreement).

Results

Experts believed that denying patients transplantation based solely on expected patient survival was inequitable to frail or cognitively impaired candidates; 100% agreed that frailty and cognitive impairment are important factors to consider during KT evaluation. There was consensus that health related quality of life and social support are important to consider before waitlisting frail or cognitively impaired patients. Experts identified important factors to consider before waitlisting frail (likely to benefit from KT, frailty reversibility, age, and medical contraindications) and cognitively impaired (degree of impairment and medication adherence) patients.

Conclusions

Clinical experts believed it was ethically unacceptable to allocate organs solely based on patients’ expected survival; frailty and cognitive impairment should be measured at evaluation when weighed against other clinical factors. Ethical guidelines regarding the use of frailty and cognitive function during KT evaluation ought to be developed.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-022-03209-x.

The Kidney Transplant Equity Index: Improving Racial and Ethnic Minority Access to Transplantation

OBJECTIVES

To develop a scalable metric which quantifies kidney transplant (KT) centers' performance providing equitable access to KT for minority patients, based on the individualized pre-listing prevalence of End-Stage Renal Disease (ESRD).

SUMMARY BACKGROUND DATA

Racial and ethnic disparities for access to transplant in patients with ESRD are well described; however, variation in care among KT centers remains unknown. Furthermore, no mechanism exists that quantifies how well a KT center provides equitable access to KT for minority patients with ESRD.

METHODS

From 2013-2018, custom datasets from the United States Renal Data System and United Network for Organ Sharing were merged to calculate the Kidney Transplant Equity Index (KTEI), defined as: the number of minority patients transplanted at a center relative to the prevalence of minority patients with ESRD in each center's health service area. Markers of socioeconomic status (SES) and recipient outcomes were compared between high and low KTEI centers.

RESULTS

249 transplant centers performed 111,959 KTs relative to 475,914 non-transplanted patients with ESRD. High KTEI centers performed more KTs for Black (105.5 vs. 24, P<0.001), Hispanic (55.5 vs. 7, P<0.001), and American Indian (1.0 vs. 0.0, P<0.001) patients than low KTEI centers. In addition, high KTEI centers transplanted more patients with higher unemployment (52 vs. 44, P<0.001), worse social deprivation (53 vs. 46, P<0.001), and lower educational attainment (52 vs. 43, P<0.001). While providing increased access to transplant for minority and low SES populations, high KTEI centers had improved patient survival (HR: 0.86, 95% CI: 0.77-0.95).

CONCLUSIONS

The KTEI is the first metric to quantify minority access to KT incorporating the pre-listing ESRD prevalence individualized to transplant centers. KTEIs uncover significant national variation in transplant practices and identify highly equitable centers. This novel metric should be used to disseminate best practices for minority and low socioeconomic patients with ESRD.

Survey of current transplant center practices regarding COVID-19 vaccine mandates in the United States

An electronic survey canvassing current policies of transplant centers regarding a COVID-19 vaccine mandate for transplant candidates and living donors was distributed to clinicians at US solid organ transplant centers performing transplants from October 14, 2021-November 15, 2021. Responses were received from staff at 141 unique transplant centers. These respondents represented 56.4% of US transplant centers, and responding centers performed 78.5% of kidney transplants and 82.4% of liver transplants in the year prior to survey administration. Only 35.7% of centers reported implementing a vaccine mandate, while 60.7% reported that vaccination was not required. A minority (42%) of responding centers with a vaccine mandate for transplant candidates also mandated vaccination for living organ donors. Centers with a vaccine mandate most frequently cited clinical evidence supporting the efficacy of pre-transplant vaccination (82%) and stewardship obligations to ensure organs were transplanted into the lowest risk patients (64%). Centers without a vaccine mandate cited a variety of reasons including administrative, equity, and legal considerations for their decision. Transplant centers in the United States exhibit significant heterogeneity in COVID-19 vaccination mandate policies for transplant candidates. While all centers encourage vaccination, most centers have not mandated COVID-19 vaccination for candidates and living donors, citing administrative opposition, legal prohibitions, and concern about equity in access to transplants.

Past and Present Policy Efforts in Achieving Racial Equity in Kidney Transplantation

Purpose of Review

Recent Findings

Summary

Black-White Inequities in Kidney Disease Mortality Across the 30 Most Populous US Cities

OBJECTIVES

To examine city-level kidney disease mortality rates and Black:White racial inequities for the USA and its largest cities, and to determine if these measures changed over the past decade.

METHODS

We used National Vital Statistics System mortality data and American Community Survey population estimates to calculate age-standardized kidney disease mortality rates for the non-Hispanic Black (Black), non-Hispanic White (White), and total populations for the USA and the 30 most populous US cities. We examined two time points, 2008-2013 (T1) and 2014-2018 (T2), and assessed changes in rates and inequities over time. Racial inequities were measured with Black:White mortality rate ratios and rate differences.

RESULTS

Kidney disease mortality rates varied from 2.5 (per 100,000) in San Diego to 24.6 in Houston at T2. The Black kidney disease mortality rate was higher than the White rate in the USA and all cities studied at both time points. In T2, the Black mortality rate ranged from 7.9 in New York to 45.4 in Charlotte, while the White mortality rate ranged from 2.0 in San Diego to 18.6 in Indianapolis. At T2, the Black:White rate ratio ranged from 1.79 (95% CI 1.62-1.99) in Philadelphia to 5.25 (95% CI 3.40-8.10) in Washington, DC, compared to the US rate ratio of 2.28 (95% CI 2.25-2.30). Between T1 and T2, only one city (Nashville) saw a significant decrease in the Black:White mortality gap.

CONCLUSIONS

The largest US cities experience widely varying kidney disease mortality rates and widespread racial inequities. These local data on racial inequities in kidney disease mortality can be used by city leaders and health stakeholders to increase awareness, guide the allocation of limited resources, monitor trends over time, and support targeted population health strategies.

HLA Homozygosity and Likelihood of Sensitization in Kidney Transplant Candidates

Background.

Homozygosity for HLAs has been associated with adverse outcomes after viral infection as well as pregnancy-induced HLA sensitization. We sought to assess the relationship between HLA locus homozygosity and the level of HLA antibody sensitization.

Methods.

We measured sensitization using the calculated panel reactive antibody value for a large cohort of 147 461 patients added to the US OPTN/United Network for Organ Sharing kidney transplant waitlist between December 2014 and December 2019. We used multinomial logistic modeling to compare 62 510 sensitized patients to 84 955 unsensitized controls.

Results.

We found that the number of homozygous HLA loci was strongly associated with the level of sensitization. Within mildly, highly, or extremely sensitized candidates, women displayed a higher relative abundance of HLA homozygosity at multiple HLA loci as compared with men, with attenuation of this effect in Black candidates. In a multivariable logistic model, the number of homozygous HLA loci interacted with female sex but not with other factors associated with sensitization, including recipient ethnicity and a history of prior kidney transplant.

Conclusions.

This study shows that HLA homozygosity is an innate genetic factor that affects the likelihood of HLA sensitization. Further research is needed to identify the immunologic mechanisms that underlie this observation.

The Combined Roles of Race/Ethnicity and Substance Use in Predicting Likelihood of Kidney Transplantation

BACKGROUND

Racial/ethnic minorities face known disparities in likelihood of kidney transplantation. These disparities may be exacerbated when coupled with ongoing substance use, a factor also reducing likelihood of transplantation. We examined whether race/ethnicity in combination with ongoing substance use predicted incidence of transplantation.

METHODS

Patients were enrolled between March 2010 and October 2012 at the time of transplant evaluation. Substance use data were retrieved from transplant evaluations. Following descriptive analyses, the primary multivariable analyses evaluated whether, relative to the referent group (White patients with no substance use), racial/ethnic minority patients using any substances at the time of evaluation were less likely to receive transplants by the end of study follow-up (August 2020).

RESULTS

Among 1152 patients, 69% were non-Hispanic White, 23% non-Hispanic Black, and 8% Other racial/ethnic minorities. White, Black, and Other patients differed in percentages of current tobacco smoking (15%, 26%, and 18%, respectively; P = 0.002) and illicit substance use (3%, 8%, and 9%; P < 0.001) but not heavy alcohol consumption (2%, 4%, and 1%; P = 0.346). Black and Other minority patients using substances were each less likely to receive transplants than the referent group (hazard ratios ≤0.45, P ≤ 0.021). Neither White patients using substances nor racial/ethnic minority nonusers differed from the referent group in transplant rates. Additional analyses indicated that these effects reflected differences in waitlisting rates; once waitlisted, study groups did not differ in transplant rates.

CONCLUSIONS

The combination of minority race/ethnicity and substance use may lead to unique disparities in likelihood of transplantation. To facilitate equity, strategies should be considered to remove any barriers to referral for and receipt of substance use care in racial/ethnic minorities.

Human leukocyte antigen antibody sensitization, lung transplantation, and health equity

Women with advanced lung disease, particularly Black and Hispanic women, are more likely than other patients to have anti-human leukocyte (HLA) antibodies against potential donors. Sensitized patients, especially those who are highly sensitized, are less likely to be listed for lung transplant or to be considered candidates for mechanical circulatory support. They are also at higher risk for waitlist death. Institutional variability in approach to HLA antibody screening and pre-transplant management creates barriers to transplant that disproportionately impact Black and Hispanic women. At the same time, our understanding of the clinical significance of pre-transplant antibodies lags behind the sophistication of our screening assays. The lack of national data on pre- and post-transplant HLA antibody characteristics hinders research into strategies to mitigate concerns about these antibodies and to improve access to lung transplant among sensitized patients. Ongoing work should be done to identify clinically higher risk antibodies, to develop better strategies for safely crossing antibodies at the time of transplant, and to model changes in lung allocation to give priority to sensitized patients for a HLA antibody-antigen compatible donors. These priorities mandate a commitment to collaborative, multicenter research and to real time translation of results to clinical practice and allocation policy.

A scoping review of inequities in access to organ transplant in the United States

Background

Organ transplant is the preferred treatment for end-stage organ disease, yet the majority of patients with end-stage organ disease are never placed on the transplant waiting list. Limited access to the transplant waiting list combined with the scarcity of the organ pool result in over 100,000 deaths annually in the United States. Patients face unique barriers to referral and acceptance for organ transplant based on social determinants of health, and patients from disenfranchised groups suffer from disproportionately lower rates of transplantation. Our objective was to review the literature describing disparities in access to organ transplantation based on social determinants of health to integrate the existing knowledge and guide future research.

Methods

We conducted a scoping review of the literature reporting disparities in access to heart, lung, liver, pancreas and kidney transplantation based on social determinants of health (race, income, education, geography, insurance status, health literacy and engagement). Included studies were categorized based on steps along the transplant care continuum: referral for transplant, transplant evaluation and selection, living donor identification/evaluation, and waitlist outcomes.

Results

Our search generated 16,643 studies, of which 227 were included in our final review. Of these, 34 focused on disparities in referral for transplantation among patients with chronic organ disease, 82 on transplant selection processes, 50 on living donors, and 61 on waitlist management. In total, 15 studies involved the thoracic organs (heart, lung), 209 involved the abdominal organs (kidney, liver, pancreas), and three involved multiple organs. Racial and ethnic minorities, women, and patients in lower socioeconomic status groups were less likely to be referred, evaluated, and added to the waiting list for organ transplant. The quality of the data describing these disparities across the transplant literature was variable and overwhelmingly focused on kidney transplant.

Conclusions

This review contextualizes the quality of the data, identifies seminal work by organ, and reports gaps in the literature where future research on disparities in organ transplantation should focus. Future work should investigate the association of social determinants of health with access to the organ transplant waiting list, with a focus on prospective analyses that assess interventions to improve health equity.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12939-021-01616-x.

Evaluation of Community-Level Vulnerability and Racial Disparities in Living Donor Kidney Transplant

Importance

Living donor kidney transplant (LDKT) is the ideal treatment for end-stage kidney disease, but racial disparities in LDKT have increased over the last 2 decades. Recipient clinical and social factors do not account for LDKT racial inequities, although comprehensive measures of community-level vulnerability have not been assessed.

Objective

To determine if racial disparities persist in LDKT independent of community-level vulnerability.

Design, Setting, and Participants

This retrospective, multicenter, cross-sectional study included data from 19 287 adult kidney-only transplant recipients in the Scientific Registry of Transplant Recipients. The study included individuals who underwent transplant between January 1 and December 31, 2018.

Exposures

Recipient race and the 2018 US Centers for Disease Control and Prevention Social Vulnerability Index (SVI). Census tract-level SVI data were linked to census tracts within each recipient zip code. The median SVI measure among the census tracts within a zip code was used to describe community-level vulnerability.

Main Outcomes and Measures

Kidney transplant donor type (deceased vs living). Modified Poisson regression was used to evaluate the association between SVI and LDKT, and to estimate LDKT likelihood among races, independent of community-level vulnerability and recipient-level characteristics.

Results

Among 19 287 kidney transplant recipients, 6080 (32%) received LDKT. A total of 11 582 (60%) were male, and the median (interquartile range) age was 54 (43-63) years. There were 760 Black LDKT recipients (13%), 4865 White LDKT recipients (80%), and 455 LDKT recipients of other races (7%; American Indian, Asian, multiracial, and Pacific Islander). Recipients who lived in communities with higher SVI (ie, more vulnerable) had lower likelihood of LDKT compared with recipients who lived in communities with lower SVI (ie, less vulnerable) (adjusted relative risk [aRR], 0.97; 95% CI, 0.96-0.98; P < .001). Independent of community-level vulnerability, compared with White recipients, Black recipients had 37% lower likelihood (aRR, 0.63; 95% CI, 0.59-0.67; P < .001) and recipients of other races had 24% lower likelihood (aRR, 0.76; 95% CI, 0.70-0.82; P < .001) of LDKT. The interaction between SVI and race was significant among Black recipients, such that the disparity in LDKT between Black and White recipients increased with greater community-level vulnerability (ratio of aRRs, 0.67; 95% CI, 0.51-0.87; P = .003).

Conclusions and Relevance

Community-level vulnerability is associated with access to LDKT but only partially explains LDKT racial disparities. The adverse effects of living in more vulnerable communities were worse for Black recipients. The interaction of these constructs is worrisome and suggests evaluation of other health system factors that may contribute to LDKT racial disparities is needed.

Racial Disparities in Pediatric Kidney Transplantation under the New Kidney Allocation System in the United States

BACKGROUND AND OBJECTIVES

In December 2014, the Kidney Allocation System (KAS) was implemented to improve equity in access to transplantation, but preliminary studies in children show mixed results. Thus, we aimed to assess how the 2014 KAS policy change affected racial and ethnic disparities in pediatric kidney transplantation access and related outcomes.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We performed a retrospective cohort study of children <18 years of age active on the kidney transplant list from 2008 to 2019 using the Scientific Registry of Transplant Recipients. Log-logistic accelerated failure time models were used to determine the time from first activation on the transplant list and the time on dialysis to deceased donor transplant, each with KAS era or race and ethnicity as the exposure of interest. We used logistic regression to assess odds of delayed graft function. Log-rank tests assessed time to graft loss within racial and ethnic groups across KAS eras.

RESULTS

All children experienced longer wait times from activation to transplantation post-KAS. In univariable analysis, Black and Hispanic children and other children of color experienced longer times from activation to transplant compared with White children in both eras; this finding was largely attenuated after multivariable analysis (time ratio, 1.16; 95% confidence interval, 1.01 to 1.32; time ratio, 1.13; 95% confidence interval, 1.00 to 1.28; and time ratio, 1.17; 95% confidence interval, 0.96 to 1.41 post-KAS, respectively). Multivariable analysis also showed that racial and ethnic disparities in time from dialysis initiation to transplantation in the pre-KAS era were mitigated in the post-KAS era. There were no disparities in odds of delayed graft function. Black and Hispanic children experienced longer times with a functioning graft in the post-KAS era.

CONCLUSIONS

No racial and ethnic disparities from activation to deceased donor transplantation were seen before or after implementation of the KAS in multivariable analysis, whereas time on dialysis to transplantation and odds of short-term graft loss improved in equity after the implementation of the KAS, without compromising disparities in delayed graft function.

PODCAST

This article contains a podcast at https://www.asn-online.org/media/podcast/CJASN/2021_12_07_CJN06740521.mp3.

Inactive status is an independent predictor of liver transplant waitlist mortality and is associated with a transplant centers median meld at transplant

BACKGROUND

Approximately 30% of patients on the liver transplant waitlist experience at least one inactive status change which makes them temporarily ineligible to receive a deceased donor transplant. We hypothesized that inactive status would be associated with higher mortality which may differ on a transplant centers' or donor service areas' (DSA) Median MELD at Transplant (MMaT).

METHODS

Multi-state models were constructed (OPTN database;06/18/2013-06/08/2018) using DSA-level and transplant center-level data where MMaT were numerically ranked and categorized into tertiles. Hazards ratios were calculated between DSA and transplant center tertiles, stratified by MELD score, to determine differences in inactive to active transition probabilities.

RESULTS

7,625 (30.2% of sample registrants;25,216 total) experienced at least one inactive status change in the DSA-level cohort and 7,623 experienced at least one inactive status change in the transplant-center level cohort (30.2% of sample registrants;25,211 total). Inactive patients with MELD≤34 had a higher probability of becoming re-activated if they were waitlisted in a low or medium MMaT transplant center or DSA. Transplant rates were higher and lower re-activation probability was associated with higher mortality for the MELD 26-34 group in the high MMaT tertile. There were no significant differences in re-activation, transplant probability, or waitlist mortality for inactivated patients with MELD≥35 regardless of a DSA's or center's MMaT.

CONCLUSION

This study shows that an inactive status change is independently associated with waitlist mortality. This association differs by a centers' and a DSAs' MMaT. Prioritization through care coordination to resolve issues of inactivity is fundamental to improving access.

Disparities in Access to Preemptive Repeat Kidney Transplant: Still Missing the Mark?

Background

The need for repeat transplant due to failing kidney allografts is increasing over time. The benefit of preemptive kidney retransplant (PKre-T) is controversial. Marginalized populations are less likely to undergo their first transplant preemptively; however, whether inequities exist for those undergoing PKre-T is unknown.

Methods

We performed a cohort study of adult patients undergoing live and deceased kidney transplant in the United States from 2000 to 2018 identified using the Scientific Registry of Transplant Recipients, and we identified patients with first preemptive kidney transplant (PKT) and PKre-T. In the primary analysis, a multivariable logistic regression was used to identify independent predictors of PKre-T. In secondary analyses, multivariable Cox models were used to determine the association of PKre-T with death-censored and all-cause graft loss.

Results

In total, 4910 (15.5%) patients underwent PKre-T, and 43,293 (19.1%) underwent first PKT. Inequities in access to PKre-T persisted (OR, 0.49; 95% CI, 0.44 to 0.55 for unemployed versus full time; OR, 1.61; 95% CI, 1.14 to 2.25 for graduate school versus not completing high school; OR, 0.61; 95% CI, 0.52 to 0.70 for Black versus White race); 7.1% of all transplanted Black patients received PKre-T versus 17.4% of White patients. Women were more likely to undergo PKre-T than men (OR, 1.42; 95% CI, 1.29 to 1.57). PKre-T was associated with superior graft survival relative to retransplant after a period of dialysis (HR, 0.73; 95% CI, 0.67 to 0.80 for all-cause graft failure; HR, 0.72; 95% CI, 0.65 to 0.81 for death-censored graft loss).

Conclusions

Despite improved patient and graft survival, inequities in access to PKre-T persist. Patients with lower education, patients with reduced employment status, patients of Black race, and men are less likely to receive PKre-T.

Removal of the Black race coefficient from the estimated glomerular filtration equation improves transplant eligibility for Black patients at a single center

Race is a social construct that cannot be measured, can be used imprecisely and may contribute to disparities in kidney transplant access for Black patients. At Beth Israel Deaconess Medical Center, we dropped the Black race coefficient in the estimated glomerular filtration rate (eGFR) report in 2017. We conducted a quality improvement project to examine the impact of this change. Before the change, only 26% of our Black patients were listed for preemptive transplant compared to 70% of White patients. Since the change, we found a steady increase in the percentage of Black patients listed before starting dialysis. The average eGFR at listing prior to 2017 was significantly lower in Black patients but after, there was no longer a significant difference. Nine patients "gained" an average of 457 days of wait time directly related to discarding the Black race coefficient. Increased time on the list prior to dialysis initiation allows for evaluation of potential live donors and improves the possibility of a pre-emptive live or deceased donor transplant and allows for a shorter period on dialysis before transplant. In this single center initiative, we demonstrate the benefit of discarding race from the eGFR report for Black patients awaiting kidney transplantation.

Disparities in living donation

PURPOSE OF REVIEW

Living organ donation provides improved access to transplantation, thereby shortening transplant wait times and allowing for more deceased organ transplants. However, disparity in access to living donation has resulted in decreased rates of living donor transplants for some populations of patients.

RECENT FINDINGS

Though there have been marked improvements in deceased donor equity, there are still challenges as it relates to gender, racial/ethnic, and socio-economic disparity. Improvements in living donation rates in Hispanic and Asian populations are tempered by challenges in African American rates of organ donation. Socio-economic disparity may drive gender disparities in organ donation resulting in disproportionate female living donors. Tailored approaches relating to language-specific interventions as well as directed educational efforts have helped mitigate disparity. Additionally, the use of apolipoprotein1 testing and modifications of glomerular filtration rate calculators may improve rates of African American donation. This review will evaluate recent data in living donor disparity as well as highlight successes in mitigating disparity.

SUMMARY

Though there are still challenges in living donor disparity, many efforts at tailoring education and access as well as modifying living donor evaluation and identifying systemic policy changes may result in improvements in living donation rates.

Elucidating measures of systemic racism to mitigate racial disparities in kidney transplantation

PURPOSE OF REVIEW

Given recent national attention to the role of racism in perpetuating racial inequities in society and health, this review provides a timely and relevant summary of key measures of systemic racism in kidney transplantation. More specifically, the review identifies current and promising interventions, whereas highlighting the need for more sustainable and impactful interventions.

RECENT FINDINGS

Racial disparities persist in kidney transplantation. Black and Hispanic individuals are less likely to receive a kidney transplant than non-Hispanic Whites despite disproportionately higher rates of kidney failure. Studies demonstrate that socioeconomic factors do not fully explain existing racial disparities in transplantation. Systemic racism at all levels, individual, interpersonal, institutional, and structural, is at the core of racial disparities, and current interventions are insufficient in mitigating their effects. Thus, targeted and sustainable interventions must be implemented to mitigate systemic racism in kidney transplantation.

SUMMARY

Systemic racism in all its forms continues to influence disparities at all stages of kidney transplantation. This paper highlights recent findings that shed light on how racism contributes to racial disparities in kidney transplantation. Using these findings to identify targets and strategies for mitigation, relevant interventions and policies that show promise are detailed.

Kidney-Related Research in the United States: A Position Statement From the National Kidney Foundation and the American Society of Nephrology

Kidney disease is an important US public health problem because it affects over 37 million Americans, and Medicare expenditures for patients with chronic kidney disease now alone exceed $130 billion annually. Kidney disease is characterized by strong racial, ethnic, and socioeconomic disparities, and reducing kidney disease incidence will positively impact US health disparities. Due to the aging of the US population and an unabated obesity epidemic, the number of patients receiving treatment for kidney failure is anticipated to increase, which will escalate kidney disease health expenditures. The historical and current investment in kidney-related research via the National Institute of Diabetes and Digestive and Kidney Diseases has severely lagged behind ongoing expenditures for kidney disease care. Increasing research investment will identify, develop, and increase implementation of interventions to slow kidney disease progression, reduce incidence of kidney failure, enhance survival, and improve quality of life. This perspective states the urgent reasons why increasing investment in kidney-related research is important for US public health. The National Kidney Foundation and the American Society of Nephrology are working together to advocate for increased funding for the National Institute of Diabetes and Digestive and Kidney Diseases. The long-term goal is to reduce the burden of kidney disease in the US population and improve the quality of life of patients living with kidney disease.

Dismantling structural racism as a root cause of racial disparities in COVID-19 and transplantation

As the United States faces unparalleled challenges due to COVID-19, racial disparities in health and healthcare have once again taken center stage. If effective interventions to address racial disparities in transplantation, including those magnified by COVID-19, are to be designed and implemented at the national level, it is first critical to understand the complex mechanisms by which structural, institutional, interpersonal, and internalized racism influence the presence of racial disparities in healthcare and transplantation. Specifically, we must deeply re-evaluate how scientists and clinicians think about race in the transplant context, and we must actively shift our efforts from merely observing disparities to acknowledging and acting on racism as a root cause underlying the vast majority of these disparities. We must do better to ensure equitable access and outcomes for all transplant patients, including within the current COVID-19 pandemic. We respectfully offer this viewpoint as a call to action to every reader to join us in working together to help dismantle racist influences and advance transplant equity.

Association between ethnicity and kidney transplant waitlist outcomes beyond estimated post-transplant survival score

White kidney transplant candidates have the highest pre-transplant mortality rate compared to other ethnicities. The reason for a higher mortality rate is not well-understood. Estimated post-transplant survival (EPTS) score has been used to predict patient survival after transplant and may be associated with pre-transplant survival. First-time kidney transplant candidates listed between 2015 and 2018 were identified from the Organ Procurement Transplantation Network database. Individuals listed for multiple organs, at multiple centers, and age <18 years were excluded. We examined the impact of ethnicity on waitlist mortality and delisting. A total of 114 806 candidates were included. The study population was categorized into four groups which were 43% white, 28% Black, 19.2% Hispanic, and 9.8% "other ethnicities." At 5.2 years, the cumulative incidences of death and delist were 32%, 31%, 29%, and 26%, respectively. Compared to whites, adjusted subdistribution hazard ratio (aSHR) for death and delist among Black, Hispanics, and "other ethnicities" were 0.92 (95% CI 0.89-0.95), 0.89 (95% CI 0.85-0.91), and 0.76 (95% CI 0.72-0.80) after adjustment by EPTS along with other factors, respectively. After adjusting for EPTS score along with additional confounding factors and functional status at initial listing, white ethnicity was independently associated with an increased risk for death and delist.

Racial Difference in the Association of Long-Term Exposure to Fine Particulate Matter (PM2.5) and Cardiovascular Disease Mortality among Renal Transplant Recipients

Ambient air pollutants are known risk factors for cardiovascular disease (CVD) morbidity and mortality with significant racial disparities. However, few studies have explored racial differences among highly susceptible subpopulations, such as renal transplant recipients (RTRs). Despite improvements in quality of life after transplantation, CVD remains the major cause of mortality, especially among Black recipients. This study aimed to evaluate potential racial differences in the association between long-term levels of PM2.5 and the risk of all-cause, total CVD, and coronary heart disease (CHD) mortality among RTRs. This retrospective study consists of 93,857 non-smoking adults who received a renal transplant between 2001 and 2015. Time-dependent Cox regression was used to assess the association between annual concentrations of PM2.5 and mortality risk. In the multivariable-adjusted models, a 10 μg/m3 increase in ambient PM2.5 levels found increased risk of all-cause (HR = 3.45, 95% CI: 3.08-3.78), CVD (HR = 2.38, 95% CI: 1.94-2.92), and CHD mortality (HR = 3.10, 95% CI: 1.96-4.90). Black recipients had higher risks of all-cause (HR = 4.09, 95% CI: 3.43-4.88) and CHD mortality (HR = 6.73, 95% CI: 2.96-15.32). High levels of ambient PM2.5 were associated with all-cause, CVD, and CHD mortality. The association tended to be higher among Black recipients than non-Blacks.

Wait expectations: The impact of delisting as an outcome from the kidney transplant waitlist

BACKGROUND

While kidney transplantation is optimal for the treatment of end-stage kidney disease, available organs do not meet demand. Little is known about the outcomes of patients who are delisted (removed from the waitlist) and unable to benefit from transplant. We describe patients who are delisted and their life expectancy after delisting.

METHODS

Patients ≥ 18 years listed for deceased donor kidney transplant between 01/2003 and 12/2013 were identified in the Scientific Registry of Transplant Recipients and followed through 12/2018. A competing risk model was used to measure the association of demographic and clinical factors with waitlist outcomes of delisting, transplant, and death. Multivariate Cox modeling was used to evaluate factors associated with death after delisting.

RESULTS

Of 324,582 patients listed, 18.0% were delisted, most common reasons were "too sick" or "other." After delisting, half (49.7%) had died by end of follow-up; time to death after removal was 5 years. Increasing age and public insurance were associated with increased risk of death.

CONCLUSIONS

Nearly one in five patients will be delisted from the kidney transplant waitlist. These patients live a surprisingly long time after removal. Much remains unknown about these patients, which could be improved through data collection. Delisting is an important patient outcome that warrants further exploration.

Social Determinants of Health and Race Disparities in Kidney Transplant

BACKGROUND AND OBJECTIVES

Black patients have a higher incidence of kidney failure but lower rate of deceased- and living-donor kidney transplantation compared with White patients, even after taking differences in comorbidities into account. We assessed whether social determinants of health (e.g., demographics, cultural, psychosocial, knowledge factors) could account for race differences in receiving deceased- and living-donor kidney transplantation.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Via medical record review, we prospectively followed 1056 patients referred for kidney transplant (2010-2012), who completed an interview soon after kidney transplant evaluation, until their kidney transplant. We used multivariable competing risk models to estimate the cumulative incidence of receipt of any kidney transplant, deceased-donor transplant, or living-donor transplant, and the factors associated with each outcome.

RESULTS

Even after accounting for social determinants of health, Black patients had a lower likelihood of kidney transplant (subdistribution hazard ratio, 0.74; 95% confidence interval, 0.55 to 0.99) and living-donor transplant (subdistribution hazard ratio, 0.49; 95% confidence interval, 0.26 to 0.95), but not deceased-donor transplant (subdistribution hazard ratio, 0.92; 95% confidence interval, 0.67 to 1.26). Black race, older age, lower income, public insurance, more comorbidities, being transplanted before changes to the Kidney Allocation System, greater religiosity, less social support, less transplant knowledge, and fewer learning activities were each associated with a lower probability of any kidney transplant. Older age, more comorbidities, being transplanted before changes to the Kidney Allocation System, greater religiosity, less social support, and fewer learning activities were each associated with a lower probability of deceased-donor transplant. Black race, older age, lower income, public insurance, higher body mass index, dialysis before kidney transplant, not presenting with a potential living donor, religious objection to living-donor transplant, and less transplant knowledge were each associated with a lower probability of living-donor transplant.

CONCLUSIONS

Race and social determinants of health are associated with the likelihood of undergoing kidney transplant.

Examining the Potential Impact of Race Multiplier Utilization in Estimated Glomerular Filtration Rate Calculation on African-American Care Outcomes

BACKGROUND

Advancing health equity entails reducing disparities in care. African-American patients with chronic kidney disease (CKD) have poorer outcomes, including dialysis access placement and transplantation. Estimated glomerular filtration rate (eGFR) equations, which assign higher eGFR values to African-American patients, may be a mechanism for inequitable outcomes. Electronic health record-based registries enable population-based examination of care across racial groups.

OBJECTIVE

To examine the impact of the race multiplier for African-Americans in the CKD-EPI eGFR equation on CKD classification and care delivery.

DESIGN

Cross-sectional study SETTING: Two large academic medical centers and affiliated community primary care and specialty practices.

PARTICIPANTS

A total of 56,845 patients in the Partners HealthCare System CKD registry in June 2019, among whom 2225 (3.9%) were African-American.

MEASUREMENTS

Exposures included race, age, sex, comorbidities, and eGFR. Outcomes were transplant referral and dialysis access placement.

RESULTS

Of 2225 African-American patients, 743 (33.4%) would hypothetically be reclassified to a more severe CKD stage if the race multiplier were removed from the CKD-EPI equation. Similarly, 167 of 687 (24.3%) would be reclassified from stage 3B to stage 4. Finally, 64 of 2069 patients (3.1%) would be reassigned from eGFR > 20 ml/min/1.73 m2 to eGFR ≤ 20 ml/min/1.73 m2, meeting the criterion for accumulating kidney transplant priority. Zero of 64 African-American patients with an eGFR ≤ 20 ml/min/1.73 m2 after the race multiplier was removed were referred, evaluated, or waitlisted for kidney transplant, compared to 19.2% of African-American patients with eGFR ≤ 20 ml/min/1.73 m2 with the default CKD-EPI equation.

LIMITATIONS

Single healthcare system in the Northeastern United States and relatively small African-American patient cohort may limit generalizability.

CONCLUSIONS

Our study reveals a meaningful impact of race-adjusted eGFR on the care provided to the African-American CKD patient population.

High Social Vulnerability and "Textbook Outcomes" after Cancer Operation

BACKGROUND

The effect of community-level factors on surgical outcomes has not been well examined. We sought to characterize differences in "textbook outcomes" (TO) relative to social vulnerability among Medicare beneficiaries who underwent operations for cancer.

METHODS

Individuals who underwent operations for lung, esophageal, colon, or rectal cancer between 2013 and 2017 were identified using the Medicare database, which was merged with the CDC's Social Vulnerability Index (SVI). TO was defined as surgical episodes with the absence of complications, extended length of stay, readmission, and mortality. The association of SVI and TO was assessed using mixed-effects logistic regression.

RESULTS

Among 203,800 patients (colon, n = 113,929; lung, n = 70,642; rectal, n = 14,849; and esophageal, n = 4,380), median age was 75 years (interquartile range 70 to 80 years) and the overwhelming majority of patients was White (n = 184,989 [90.8%]). The overall incidence of TO was 56.1% (n = 114,393). The incidence of complications (low SVI: 21.5% vs high SVI: 24.0%) and 90-day mortality (low SVI: 7.0% vs high SVI: 8.4%) were higher among patients from highly vulnerable neighborhoods (both, p < 0.05). In turn, there were lower odds of achieving TO among high-vs low-SVI patients (odds ratio 0.83; 95% CI, 0.78 to 0.87). Although high-SVI White patients had 10% lower odds (95% CI, 0.87 to 0.93) of achieving TO, high-SVI non-White patients were at 22% lower odds (95% CI, 0.71 to 0.85) of postoperative TO. Compared with low-SVI White patients, high-SVI minority patients had 47% increased odds of an extended length of stay, 40% increased odds of a complication, and 23% increased odds of 90-day mortality (all, p < 0.05).

CONCLUSIONS

Only roughly one-half of Medicare beneficiaries achieved the composite optimal TO quality metric. Social vulnerability was associated with lower attainment of TO and an increased risk of adverse postoperative surgical outcomes after several common oncologic procedures. The effect of high SVI was most pronounced among minority patients.

Association of the Estimated Glomerular Filtration Rate With vs Without a Coefficient for Race With Time to Eligibility for Kidney Transplant

IMPORTANCE

Kidney transplant is associated with improved survival and quality of life among patients with kidney failure; however, significant racial disparities have been noted in transplant access. Common equations that estimate glomerular filtration rate (eGFR) include adjustment for Black race; however, how inclusion of the race coefficient in common eGFR equations corresponds with measured GFR and whether it is associated with delayed eligibility for kidney transplant listing are unknown.

OBJECTIVE

To compare eGFR with measured GFR and evaluate the association between eGFR calculated with vs without a coefficient for race and time to eligibility for kidney transplant.

DESIGN, SETTING, AND PARTICIPANTS

This prospective cohort study used data from the Chronic Renal Insufficiency Cohort, a multicenter cohort study of participants with chronic kidney disease (CKD). Self-identified Black participants from that study were enrolled between April 2003 and September 2008, with follow-up through December 2018. Statistical analyses were completed on November 11, 2020.

EXPOSURE

Estimated GFR, measured annually and estimated using the creatinine-based Chronic Kidney Disease-Epidemiology (CKD-EPI) equation with and without a race coefficient.

MAIN OUTCOMES AND MEASURES

Iothalamate GFR (iGFR) measured in a subset of participants (n = 311) and time to achievement of an eGFR less than 20 mL/min/1.73 m2, an established threshold for kidney transplant referral and listing.

RESULTS

Among 1658 self-identified Black participants, mean (SD) age was 58 (11) years, 848 (51%) were female, and mean (SD) eGFR was 44 (15) mL/min/1.73 m2. The CKD-EPI eGFR with the race coefficient overestimated iGFR by a mean of 3.1 mL/min/1.73 m2 (95% CI, 2.2-3.9 mL/min/1.73 m2; P < .001). The mean difference between CKD-EPI eGFR without the race coefficient and iGFR was of smaller magnitude (-1.7 mL/min/1.73 m2; 95% CI, -2.5 to -0.9 mL/min/1.73 m2). For participants with an iGFR of 20 to 25 mL/min/1.73 m2, the mean difference in eGFR with vs without the race coefficient and iGFR was 5.1 mL/min/1.73 m2 (95% CI, 3.3-6.9 mL/min/1.73 m2) vs 1.3 mL/min/1.73 m2 (95% CI, -0.3 to 2.9 mL/min/1.73 m2). Over a median follow-up time of 4 years (interquartile range, 1-10 years), use of eGFR calculated without vs with the race coefficient was associated with a 35% (95% CI, 29%-41%) higher risk of achieving an eGFR less than 20 mL/min/1.73 m2 and a shorter median time to this end point of 1.9 years.

CONCLUSIONS AND RELEVANCE

In this cohort study, inclusion of the race coefficient in the estimation of GFR was associated with greater bias in GFR estimation and with delayed achievement of a clinical threshold for kidney transplant referral and eligibility. These findings suggest that nephrologists and transplant programs should be cautious when using current estimating equations to determine kidney transplant eligibility.

Substituting imputation of HLA antigens for high-resolution HLA typing: Evaluation of a multiethnic population and implications for clinical decision making in transplantation

Molecular mismatch analysis for assessment of histocompatibility in transplantation requires high-resolution HLA typing. Algorithms to "guesstimate" high-resolution from low-resolution typing exist, but their accuracy remains unknown. We converted high-resolution, sequence-based, HLA typing of 310 subjects from an ethnically heterogeneous population to low-resolution equivalents and tested the ability of the NMDP HaploStats and HLA Matchmaker programs to impute/reproduce the measured high-resolution HLA type, using the more common "winner-takes-all" approach. Only 35.6% of the HaploStats imputed HLA-A, -B, -C, -DRB1, and -DQB1 haplotypes had no mistakes, and the accuracy was significantly lower for non-Caucasians (29.1%) compared to Caucasians (45.2%) (odds ratio [OR], 0.5; 95% confidence interval [CI], 0.3-0.8; P = .004). HLA Matchmaker was not able to provide high-resolution haplotypes for 45.2% of Caucasian subjects and 63.5% of non-Caucasian subjects (P = .002). Of those with an imputed result, only 10.3% of Caucasians and 4.8% of non-Caucasians had accurate 10-allele high-resolution output. Eplet analysis revealed additional, inaccurate eplets in 37% of individuals, with 22.5% showing at least 2 additional, inaccurate eplets; incorrect eplets were more common among non-Caucasians (OR, 1.8; 95% CI, 1.1-2.9; P = .018). Given this high error rate, caution should be taken before using imputation tools for clinical or research purposes, especially for non-Caucasian individuals.