Distance to Kidney Transplant Center and Access to Early Steps in the Kidney Transplantation Process in the Southeastern United States

Disentangling Dialysis Facility and Transplant Center Factors on Evaluation Start Following Referral for Kidney Transplantation: A Regional Study in the United States

Rationale & Objective

Little is known about the relative importance of dialysis facilities and transplant centers on variability in starting an evaluation among patients referred for kidney transplant. The primary objective of this study was to leverage cross-classified multilevel modeling to simultaneously examine the contextual effects of dialysis facilities and transplant centers on variation in the start of the transplant evaluation process.

Study Design

Retrospective cohort study.

Setting & Participants

Dialysis patients referred for kidney transplant to transplant centers across the Southeast, Northeast, New York, or Ohio River Valley US regions from January 1, 2012, to December 31, 2020, were identified from the United States Renal Data System and the Early Steps to Transplant Access Registry and followed through June 30, 2021. A total of N=25,488 referred patients were nested with 1,720 dialysis facilities and 26 transplant centers.

Outcomes

Starting an evaluation for kidney transplant at a transplant center within 6 months of referral.

Analytical Approach

A series of multilevel models were performed to estimate the variability in starting an evaluation for kidney transplant within 6 months of referral. The between-dialysis facility and/or transplant center variation in starting an evaluation was quantified using the median OR.

Results

Among 25,488 dialysis patients referred for kidney transplantation, 51% of patients started an evaluation at a transplant center within 6 months of referral. In multilevel models, the median OR between transplant centers was higher (indicating higher unexplained variability) than the dialysis facility median OR, regardless of measured patient, dialysis facility, and transplant center characteristics.

Limitations

Early transplant access data was limited to 20 of 48 transplant centers across these 4 regions.

Conclusions

When taking dialysis facilities and transplant centers into account, variation in starting an evaluation for kidney transplant appeared at both the dialysis facility and transplant center-level but was more apparent among transplant centers.

A data pipeline for secure extraction and sharing of social determinants of health

OBJECTIVES

Linking neighborhood- and patient-level data provides valuable information about the influence of upstream social determinants of health (SDOH). However, sharing of these data across health systems presents challenges. We set out to develop a pipeline to acquire, deidentify, and share neighborhood-level SDOH data across multiple health systems.

METHODS

We created a pipeline centered around Decentralized Geomarker Assessment for Multi-Site Studies (DeGAUSS) that utilizes containerization to geocode patient addresses and obtain neighborhood-level SDOH variables. We compared DeGAUSS to a third-party vendor geocoding tool available at Duke Health using a cohort of adult patients referred for abdominal transplant from January 1, 2016, to December 31, 2022. We calculated Cohen's Kappa and percent disagreement at census block group and tract levels, and by Area Deprivation Index, urbanicity, and year.

RESULTS

The pipeline successfully generated SDOH data for 97.8% of addresses. There was high concordance between DeGAUSS and the vendor tool at the census block group (0.93) and tract levels (0.95). At the block group level, disagreement proportion differed by year and urbanicity, with larger disagreement in the rural category than in micropolitan and metropolitan categories (13%, 7%, 6.2%, respectively).

DISCUSSION AND CONCLUSION

We describe a novel pipeline that can facilitate the secure acquisition and sharing of neighborhood-level SDOH without sharing PHI. The pipeline can be scaled to include additional social, climate, and environmental variables, and can be extended to an unlimited number of health systems.

Expanding the access to kidney transplantation: Strategies for kidney transplant programs

Kidney transplantation is the most successful kidney replacement therapy available, resulting in improved recipient survival and societal cost savings. Yet, nearly 70 years after the first successful kidney transplant, there are still numerous barriers and untapped opportunities that constrain the access to transplant. The literature describing these barriers is extensive, but the practices and processes to solve them are less clear. Solutions must be multidisciplinary and be the product of strong partnerships among patients, their networks, health care providers, and transplant programs. Transparency in the referral, evaluation, and listing process as well as organ selection are paramount to build such partnerships. Providing early culturally congruent and patient-centered education as well as maximizing the use of local resources to facilitate the transplant work up should be prioritized. Every opportunity to facilitate pre-emptive kidney transplantation and living donation must be taken. Promoting the use of telemedicine and kidney paired donation as standards of care can positively impact the work up completion and maximize the chances of a living donor kidney transplant.

Use of Donor-derived Cell-free DNA to Inform Tapering of Immunosuppression Therapy in Kidney Transplant Recipients: An Observational Study

Background

Immunosuppression therapy (IST) is required for allograft survival but can cause significant adverse effects. Donor-derived cell-free DNA (dd-cfDNA) is a validated noninvasive biomarker for active rejection in kidney transplant (KTx). Evidence supporting dd-cfDNA testing use in IST management is limited.

Methods

In this single-center observational study, dd-cfDNA testing was performed in 21 KTx patients considered good candidates for mycophenolic acid (MPA) reduction. Patients with dd-cfDNA <1% at the first visit (enrollment) had their MPA dosage reduced; those with dd-cfDNA ≥1% had their MPA dosage maintained. Patients were monitored with dd-cfDNA for 6 additional visits.

Results

Of 21 patients enrolled in the study, 17 were considered low risk for rejection by dd-cfDNA and underwent MPA reduction; 4 patients were considered high risk for rejection by dd-cfDNA and had their initial MPA dosage maintained. Of the 4 patients considered high risk for rejection by dd-cfDNA, 1 experienced chronic allograft nephropathy and graft loss, and another received an indication biopsy that showed no evidence of rejection. Of the 17 patients considered low risk for rejection by dd-cfDNA, none experienced allograft rejection. dd-cfDNA was used for surveillance in a 6-mo period following MPA reduction; no untoward results were noted.

Conclusions

This proof-of-concept study reports the use of dd-cfDNA to directly inform IST management in a cohort of KTx who were candidates for IST reduction.

Interpersonal Connections Are Important for Virtual Kidney Transplant Educational Program Development

Introduction: The Living Donor Navigator program is designed to mitigate disparities in living donor kidney transplantation, although geographic disparities in program participation were observed in the initial years of implementation. The purpose of this study was to understand participant perspectives regarding the use of a virtual option/alternative to expand program participation. Methods: Previous participants of the in-person navigator program were purposively sampled. Using the nominal group technique, a well-structured formative methodology to elicit participant perspectives, 2 meetings were conducted among transplant recipients and advocates (N = 13) to identify and prioritize responses to the question "What things would concern you about participating in a virtual and remote Living Donor Navigator program?" Findings: Mean participant age was 59.3 (9.3) years, and participants were 54% male and 62% white. Education levels varied from less than high school to master's degrees. Participants generated 70 unique responses, of which 36 (51.4%) received prioritization. The top 5 ranked responses of each nominal group technique meeting received approximately 50 percent (47.6% vs. 66.7%, respectively) of the total votes and described the potentially limited interpersonal connections, time conflicts, and differing content in a virtual navigator program compared to the in-person model. Discussion: These data suggest that previous participants were concerned with upholding the original design of the program, thus, virtual living donor kidney transplantation programs should aim to maintain interpersonal connections and consistency of content to ensure adequate programmatic engagement. Future research will focus on program fidelity independent of delivery modality.

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.

Racial Equity in Living Donor Kidney Transplant Centers, 2008-2018

Importance

It is unclear whether center-level factors are associated with racial equity in living donor kidney transplant (LDKT).

Objective

To evaluate center-level factors and racial equity in LDKT during an 11-year time period.

Design, Setting, and Participants

A retrospective cohort longitudinal study was completed in February 2023, of US transplant centers with at least 12 annual LDKTs from January 1, 2008, to December 31, 2018, identified in the Health Resources Services Administration database and linked to the US Renal Data System and the Scientific Registry of Transplant Recipients.

Main Outcomes and Measures

Observed and model-based estimated Black-White mean LDKT rate ratios (RRs), where an RR of 1 indicates racial equity and values less than 1 indicate a lower rate of LDKT of Black patients compared with White patients. Estimated yearly best-case center-specific LDKT RRs between Black and White individuals, where modifiable center characteristics were set to values that would facilitate access to LDKT.

Results

The final cohorts of patients included 394 625 waitlisted adults, of whom 33.1% were Black and 66.9% were White, and 57 222 adult LDKT recipients, of whom 14.1% were Black and 85.9% were White. Among 89 transplant centers, estimated yearly center-level RRs between Black and White individuals accounting for center and population characteristics ranged from 0.0557 in 2008 to 0.771 in 2018. The yearly median RRs ranged from 0.216 in 2016 to 0.285 in 2010. Model-based estimations for the hypothetical best-case scenario resulted in little change in the minimum RR (from 0.0557 to 0.0549), but a greater positive shift in the maximum RR from 0.771 to 0.895. Relative to the observed 582 LDKT in Black patients and 3837 in White patients, the 2018 hypothetical model estimated an increase of 423 (a 72.7% increase) LDKTs for Black patients and of 1838 (a 47.9% increase) LDKTs for White patients.

Conclusions and Relevance

In this cohort study of patients with kidney failure, no substantial improvement occurred over time either in the observed or the covariate-adjusted estimated RRs. Under the best-case hypothetical estimations, modifying centers' participation in the paired exchange and voucher programs and increased access to public insurance may contribute to improved racial equity in LDKT. Additional work is needed to identify center-level and program-specific strategies to improve racial equity in access to LDKT.

Increased volume of organ offers and decreased efficiency of kidney placement under circle-based kidney allocation

The newest kidney allocation policy kidney allocation system 250 (KAS250) broadened geographic distribution while increasing allocation system complexity. We studied the volume of kidney offers received by transplant centers and the efficiency of kidney placement since KAS250. We identified deceased-donor kidney offers (N = 907,848; N = 36,226 donors) to 185 US transplant centers from January 1, 2019, to December 31, 2021 (policy implemented March 15, 2021). Each unique donor offered to a center was considered a single offer. We compared the monthly volume of offers received by centers and the number of centers offered before the first acceptance using an interrupted time series approach (pre-/post-KAS250). Post-KAS250, transplant centers received more kidney offers (level change: 32.5 offers/center/mo, P < .001; slope change: 3.9 offers/center/mo, P = .003). The median monthly offer volume post-/pre-KAS250 was 195 (interquartile range 137-253) vs. 115 (76-151). There was no significant increase in deceased-donor transplant volume at the center level after KAS250, and center-specific changes in offer volume did not correlate with changes in transplant volume (r = -0.001). Post-KAS250, the number of centers to whom a kidney was offered before acceptance increased significantly (level change: 1.7 centers/donor, P < .001; slope change: 0.1 centers/donor/mo, P = .014). These findings demonstrate the logistical burden of broader organ sharing, and future allocation policy changes will need to balance equity in transplant access with the operational efficiency of the allocation system.

Variation in Kidney Transplant Referral Across Chronic Kidney Disease Programs in Ontario, Canada

Background

Eligible patients with kidney failure should have equal access to kidney transplantation. Transplant referral is the first crucial step toward receiving a kidney transplant; however, studies suggest substantial variation in the rate of kidney transplant referral across regions. The province of Ontario, Canada, has a public, single-payer health care system with 27 regional chronic kidney disease (CKD) programs. The probability of being referred for kidney transplant may not be equal across CKD programs.

Objective

To determine whether there is variability in kidney transplant referral rates across Ontario's CKD programs.

Design

Population-based cohort study using linked administrative health care databases from January 1, 2013, to November 1, 2016.

Setting

Twenty-seven regional CKD programs in the province of Ontario, Canada.

Patients

Patients approaching the need for dialysis (advanced CKD) and patients receiving maintenance dialysis (maximum follow-up: November 1, 2017).

Measurements

Kidney transplant referral.

Methods

We calculated the 1-year unadjusted cumulative probability of kidney transplant referral for Ontario's 27 CKD programs using the complement of Kaplan-Meier estimator. We calculated standardized referral ratios (SRRs) for each CKD program, using expected referrals from a 2-staged Cox proportional hazards model, adjusting for patient characteristics in the first stage. Standardized referral ratios with a value less than 1 were below the provincial average (maximum possible follow-up of 4 years 10 months). In an additional analysis, we grouped CKD programs according to 5 geographic regions.

Results

Among 8641 patients with advanced CKD, the 1-year cumulative probability of kidney transplant referral ranged from 0.9% (95% confidence interval [CI]: 0.2%-3.7%) to 21.0% (95% CI: 17.5%-25.2%) across the 27 CKD programs. The adjusted SRR ranged from 0.2 (95% CI: 0.1-0.4) to 4.2 (95% CI: 2.1-7.5). Among 6852 patients receiving maintenance dialysis, the 1-year cumulative probability of transplant referral ranged from 6.4% (95% CI: 4.0%-10.2%) to 34.5% (95% CI: 29.5%-40.1%) across CKD programs. The adjusted SRR ranged from 0.2 (95% CI: 0.1-0.3) to 1.8 (95% CI: 1.6-2.1). When we grouped CKD programs according to geographic region, we found that patients residing in Northern regions had a substantially lower 1-year cumulative probability of transplant referral.

Limitations

Our cumulative probability estimates only captured referrals within the first year of advanced CKD or maintenance dialysis initiation.

Conclusions

There is marked variability in the probability of kidney transplant referral across CKD programs operating in a publicly funded health care system.

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.

Listing at non-local transplant centers is associated with increased access to deceased donor kidney transplantation

The ability of kidney transplant candidates to travel outside of their usual place of care varies by sociodemographic factors, potentially exacerbating disparities in access. We used Transplant Referral Regions (TRRs) to overcome previous methodological barriers of using geographic distance to assess the characteristics and outcomes of patients listed for kidney transplant at centers in neighboring TRR or beyond neighboring TRRs. Among listed kidney transplant candidates, 20.9% traveled to a neighbor and 5.6% beyond a neighbor. A higher proportion of travelers were White, had some college education, and lived in ZIP codes with lower poverty. Travel to a neighbor was associated with a 7% increase in likelihood of deceased donor transplant (cHR: 1.07, 95% CI: 1.05, 1.09) and traveling beyond a neighbor with a 19% increase (cHR: 1.19, 95% CI: 1.15, 1.24). Travelers had similar rates of living donor transplant and waitlist mortality as patients who did not travel; those who traveled beyond a neighbor had slightly lower posttransplant mortality (HR: 0.91, 95% CI: 0.83, 0.99). In conclusion, the ability to travel outside of the recipient's assigned TRR increases access to transplantation and improves long-term survival.

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.

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.

Early steps to kidney transplantation among persons with HIV and end-stage renal disease in ESRD network 6

INTRODUCTION

End-stage renal disease is a significant cause of morbidity and mortality in persons with HIV (PWH). Limited data exist on access to kidney transplantation for this population.

METHODS

A dataset inclusive of incident dialysis patients between 2012 and 2016 with follow-up through December 2017 that identifies PWH and the general dialysis population of Network 6 (Georgia, North Carolina, South Carolina) was created through merging the United States Renal Data System with the southeastern early transplant access registry. Early steps to kidney transplantation and patient and dialysis facility-level characteristics that serve as barriers to transplantation were described.

RESULTS

Twenty-three thousand four hundred fourteen patients were identified; 469 were PWH. Compared to non-HIV individuals, PWH were younger (49 vs. 58 years, p < 0.001), predominantly Black (87% vs. 56% p < 0.001) and male (72% vs. 56% p < 0.001). PWH were less likely to be referred to kidney transplant within 1 year of starting dialysis (36% vs. 41% p < 0.001) and waitlisted within 1 year of evaluation-start (14% vs. 30%, p = 0.05). PWH (vs. non-PWH) waited longer for referral, evaluation-start, and waitlisting and in multivariable analysis; HIV positivity was associated with a lower probability of referral (hazard ratios [HR]: 0.70; 95% confidence intervals [CIs]: 0.62-0.80), evaluation (HR 0.66; 95% CI: 0.55-0.80), and waitlisting (HR 0.29; 95% CI: 0.20-0.41).

CONCLUSIONS

Targeted interventions are needed to improve access to kidney transplants, particularly in waitlisting, for PWH.

Initial Home Dialysis Is Increased for Rural Patients by Accessing Urban Facilities

Background

The 240,000 rural patients with end stage kidney disease in the United States have less access to nephrology care and higher mortality than those in urban settings. The Advancing American Kidney Health initiative aims to increase the use of home renal replacement therapy. Little is known about how rural patients access home dialysis and the availability and quality of rural dialysis facilities.

Methods

Incident dialysis patients in 2017 and their facilities were identified in the United States Renal Data System. Facility quality and service availability were analyzed with descriptive statistics. We assessed the availability of home dialysis methods, depending on rural versus urban counties, and then we used multivariate logistic regression to identify the likelihood of rural patients with home dialysis as their initial modality and the likelihood of rural patients changing to home dialysis within 90 days. Finally, we assessed mortality after dialysis initiation on the basis of patient home location.

Results

Of the 97,930 dialysis initiates, 15,310 (16%) were rural. Rural dialysis facilities were less likely to offer home dialysis (51% versus 54%, P<0.001). Although a greater proportion of rural patients (9% versus 8%, P<0.001) were on home dialysis, this was achieved by traveling to urban facilities to obtain home dialysis (OR=2.74, P<0.001). After adjusting for patient and facility factors, rural patients had a higher risk of mortality (HR=1.06, P=0.004).

Conclusions

Despite having fewer facilities that offer home dialysis, rural patients were more often on home dialysis methods because they traveled to urban facilities, representing an access gap. Even if rural patients accessed home dialysis at urban facilities, rural patients still suffered worse mortality. Future dialysis policy should address this access gap to improve care and overall mortality for rural patients.

Non-medical barriers in access to early steps of kidney transplantation in the United States - A scoping review

BACKGROUND

In the United States (US), barriers in access to later steps in the kidney transplantation process (i.e. waitlisting) have been well documented. Barriers in access to earlier steps (i.e. referral and evaluation) are less well described due to the lack of national surveillance data. In this review, we summarize the available literature on non-medical barriers in access to kidney transplant referral and evaluation.

METHODS

Following PRISMA guidelines, we conducted a scoping review of the literature through June 3, 2021. We included all studies (quantitative and qualitative) reporting on barriers to kidney transplant referral and evaluation in the US published from 1990 onwards in English and among adult end-stage kidney disease (ESKD) patients (PROSPERO registration number: CRD42014015027). We narratively synthesized results across studies.

RESULTS

We retrieved information from 33 studies published from 1990 to 2021 (reporting data between 1990 and 2018). Most studies (n = 28, 85%) described barriers among patient populations, three (9%) among provider populations, and two (6%) included both patients and providers. Key barriers were identified across multiple levels and included patient- (e.g. demographic, socioeconomic, sociocultural, and knowledge), provider- (e.g. miscommunication, staff availability, provider perceptions and attitudes), and system- (e.g. geography, distance to care, healthcare logistics) level factors.

CONCLUSIONS

A multi-pronged approach (e.g. targeted and systemwide interventions, and policy change) implemented at multiple levels of the healthcare system will be necessary to reduce identified barriers in access to early kidney transplant steps. Collection of national surveillance data on these early kidney transplant steps is also needed to enhance our understanding of barriers to referral and evaluation.

Nonmedical barriers to early steps in kidney transplantation among underrepresented groups in the United States

PURPOSE OF REVIEW

Despite numerous targeted interventions and policy reforms, underrepresented minorities and patients with low socioeconomic status (SES) continue to have unequal access to kidney transplant. In this review, we summarize the most recent evidence on barriers to early kidney transplant steps (i.e. referral and evaluation) among underrepresented racial and ethnic minorities and low SES groups in the United States.

RECENT FINDINGS

This review highlights the interconnectedness of several patient-level (e.g. medical mistrust, transplant knowledge, access to care), provider-level (e.g. dialysis profit status, patient--provider communication; staff accessibility), and system-level (e.g. center-specific criteria, healthcare logistics, neighborhood poverty, healthcare logistics) factors associated with lower rates of referral and evaluation among underrepresented minorities and low SES groups, and the influence of systemic racism operating at all levels.

SUMMARY

Collection of national surveillance data on early transplant steps, as well as routinely captured data on upstream social determinants of health, including the measurement of racism rather than race, is necessary to enhance our understanding of barriers to referral and evaluation. A multipronged approach (e.g. targeted and systemwide interventions, and policy change) implemented at multiple levels of the healthcare system will be necessary to reduce disparities in early transplant steps.

Effects of Social Deprivation on the Proportion of Preemptive Kidney Transplantation: A Mediation Analysis

Social inequalities in health lead to an increased risk of chronic kidney disease and less access to renal transplantation. The objective of this study was to assess the association between social deprivation estimated by the fifth quintile of the European Deprivation Index (EDI) and preemptive kidney transplantation (PKT) and to explore the potential mediators of this association.

Methods

This retrospective observational multicenter study included 8701 patients who received their first renal transplant in France between 2010 and 2014. Mediation analyses were performed to assess the direct and indirect effects of the EDI on PKT.

Results

Among the 8701 transplant recipients, 32.4% belonged to the most deprived quintile of the EDI (quintile 5) and 16% received a PKT (performed either with a deceased- or living-donor). There was a significant association between quintile 5 of the EDI and PKT (total effect: odds ratio [OR]: 0.64 [95% confidence interval (CI): 0.55-0.73]). Living-donor kidney transplantation was the main mediator of this association (natural indirect effect: OR: 0.92 [0.89-0.95]). To a lesser extent, positive cytomegalovirus and hepatitis C serologies and blood group B were also mediators (respective natural indirect effects: OR: 0.98 [95% CI: 0.95-1.00], OR: 0.99 [95% CI: 0.99-1.00], and OR: 0.99 [95% CI: 0.98-1.00], P < 0.05).

Conclusions

Our study suggests that social deprivation is associated with a decreased proportion of PKT. This association might be mitigated by promoting living-donor transplantation.

Association of Public Reporting of Medicare Dialysis Facility Quality Ratings With Access to Kidney Transplantation

IMPORTANCE

Improving the quality of dialysis care and access to kidney transplantation for patients with end-stage kidney disease is a national clinical and policy priority. The role of dialysis facility quality in increasing access to kidney transplantation is not known.

OBJECTIVE

To determine whether patient, facility, and kidney transplant waitlisting characteristics are associated with variations in dialysis center quality.

DESIGN, SETTING, AND PARTICIPANTS

This population-based cohort study is an analysis of US Renal Data System data and Medicare Dialysis Facility Compare (DFC) data from 2013 to 2018. Participants included all adult (aged ≥18 years) patients in the US Renal Data System beginning long-term dialysis in the US from 2013 to 2017 with follow-up through the end of 2018. Patients with a prior kidney transplant and matched Medicare DFC star ratings to each annual cohort of recipients were excluded. Patients at facilities without a star rating in that year were also excluded. Data analysis was performed from January to April 2021.

EXPOSURES

Dialysis center quality, as defined by Medicare DFC star ratings.

MAIN OUTCOMES AND MEASURES

The primary outcome was the proportion of patients undergoing incident dialysis who were waitlisted within 1 year of dialysis initiation. Secondary outcomes were patient and facility characteristics.

RESULTS

Of 507 581 patients beginning long-term dialysis in the US from 2013 to 2017, 291 802 (57.4%) were male, 266 517 (52.5%) were White, and the median (interquartile range) age was 65 (55-75) years. Of 5869 dialysis facilities in 2017, 132 (2.2%) were 1-star, 436 (7.4%) were 2-star, 2047 (34.9%) were 3-star, 1660 (28.3%) were 4-star, and 1594 (27.2%) were 5-star. Higher-quality dialysis facilities were associated with 47% higher odds of transplant waitlisting (odds ratio [OR], 1.47; 95% CI, 1.39-1.57 for 5-star facilities vs 1-star facilities; P < .001). Black patients were less likely than White patients to be waitlisted for transplantation (OR, 0.74; 95% CI, 0.72-0.76). In addition, patients at for-profit (OR, 0.78; 95% CI, 0.74-0.81) and rural (OR, 0.63; 95%, CI 0.58-0.68) facilities were less likely to be waitlisted for transplantation compared with those at nonprofit and urban facilities, respectively.

CONCLUSIONS AND RELEVANCE

In this cohort study, patients at higher-quality dialysis facilities had higher odds than patients at lower-quality facilities of being waitlisted for kidney transplantation within 1 year. Waitlisting rates for kidney transplantation should be considered for integration into the current Centers for Medicare & Medicaid Services DFC star ratings to incentivize dialysis facility referral to transplant centers, inform patient choice, and drive quality improvement by increasing transplant waitlisting rates.

Kidney Transplant Outcomes in Indigenous People of the Northern Great Plains of the United States

BACKGROUND

Indigenous people experience higher rates of end-stage renal disease as well as negative predictive factors that undermine kidney transplantation (KT) success. Despite these inequalities, data suggest that short-term outcomes are comparable to those of other groups, but few studies have examined this effect in the Northern Great Plains (NGP) region.

METHODS

We performed a retrospective database review to determine outcomes of KT in Indigenous people of the NGP. White and Indigenous people receiving a KT between 2000 and 2018 at a single center were examined.

RESULTS

A total of 622 KT recipients were included (117 Indigenous and 505 White). Indigenous patients were more likely to smoke, have diabetes, have higher immunologic risk, receive fewer living donor kidneys, and have longer waitlist times. In the 5 years after KT there were no significant differences in renal function, rejection events, cancer, graft failure, or patient survival. At 10 years posttransplant, Indigenous patients had twice the all-cause graft failure (odds ratio = 2.06; 95% confidence interval, 1.25-3.39) and half the survival rate (odds ratio = 0.47; 95% confidence interval, 0.29-0.76); however, this effect was not maintained once the effects of race, sex, smoking status, diabetes, preemptive transplant, high panel reactive antibody status, and transplant type were adjusted for.

CONCLUSIONS

KT outcomes in Indigenous patients in the NGP region are similar to those of White patients 5 years posttransplant, with differences emerging at 10 years that could be diminished with greater emphasis on correcting modifiable risk factors.

Association of High Burden of End-stage Kidney Disease With Decreased Kidney Transplant Rates With the Updated US Kidney Allocation Policy

Importance

The Organ Procurement and Transplantation Network (OPTN) approved changes to the US kidney allocation system in 2019. The potential effects of this policy change using transplant rates normalized to end-stage kidney disease (ESKD) incidence have not been investigated.

Objective

To estimate how the OPTN kidney allocation policy will affect areas of the US currently demonstrating low rates of kidney transplant, when accounting for the regional burden of ESKD.

Design, Setting, and Participants

This cross-sectional population-based economic evaluation analyzed access of patients with ESKD to kidney transplant in the US. Participants included patients with incident ESKD, those on the kidney transplant wait list, and those who received a kidney transplant. Data were collected from January 1 to December 31, 2017, and were analyzed in 2019.

Main Outcomes and Measures

The probability of a patient with ESKD being placed on the transplant wait list or receiving a deceased donor kidney transplant. States and donor service areas (DSAs) were compared for gains and losses in rates of transplanted kidneys under the new allocation system. Transplant rates were normalized for ESKD burden.

Results

A total of 122 659 patients had incident ESKD in the US in 2017 (58.2% men; mean [SD] age, 62.8 [15.1] years). The probability of a patient with ESKD receiving a deceased donor kidney transplant varied 3-fold across the US (from 6.36% in West Virginia to 18.68% in the District of Columbia). Modeling of the OPTN demonstrates that DSAs from New York (124%), Georgia (65%), and Illinois (56%) are estimated to experience the largest increases in deceased donor kidney allocation. Other than Georgia, these states have kidney transplant rates per incident ESKD cases above the mean (of 50 states plus the District of Columbia, New York is 16th and Illinois is 24th). In contrast, DSAs from Nevada (-74%), Ohio (-67%), and North Carolina (-61%)-each of which has a transplant rate per incident ESKD cases significantly below the mean-are estimated to experience the largest decreases in deceased donor allocation (of 50 states plus the District of Columbia, North Carolina is 34th, Ohio is 38th, and Nevada is 47th).

Conclusions and Relevance

The new OPTN-approved kidney allocation policy may result in worsening geographic disparities in access to transplants when measured against the burden of ESKD within a particular region of the US.

Association between Longer Travel Distance for Transplant Care and Access to Kidney Transplantation and Graft Survival in the United States

BACKGROUND

Transplant candidates may gain an advantage by traveling to receive care at a transplant center that may have more favorable characteristics than their local center. Factors associated with longer travel distance for transplant care and whether the excess travel distance (ETD) is associated with access to transplantation or with graft failure are unknown.

METHODS

This study of adults in the United States wait-listed for kidney transplantation in 1995-2015 used ETD, defined as distance a patient traveled beyond the nearest transplant center for initial waiting list registration. We used linear regression to examine patient and center characteristics associated with ETD and Fine-Gray models to examine the association between ETD (modeled as a spline) and time to deceased or living donor transplantation or graft failure.

RESULTS

Of 373,365 patients, 11% had an ETD≥50 miles. Traveling excess distance was more likely among patients who were of non-Black race or those whose nearest transplant center had lower annual living donor transplant volume. At an ETD of 50 miles, we observed a lower likelihood of deceased donor transplantation (subhazard ratio [SHR], 0.85; 95% confidence interval [95% CI], 0.84 to 0.87) but higher likelihood of living donor transplantation (SHR, 1.14; 95% CI, 1.12 to 1.16) compared with those who received care at their nearest center. ETD was weakly associated with higher risk of graft failure.

CONCLUSIONS

Patients who travel excess distances for transplant care have better access to living donor but not deceased donor transplantation and slightly higher risk of graft failure. Traveling excess distances is not clearly associated with better outcomes, especially if living donors are unavailable.

Toward telemedicine-compatible physical functioning assessments in kidney transplant candidates

Frailty is associated with adverse kidney transplant outcomes and can be assessed by subjective and objective metrics. There is increasing recognition of the value of metrics obtainable remotely. We compared the self‐reported SF‐36 physical functioning subscale score (SF‐36 PF) with in‐person physical performance tests (6‐min walk and sit‐to‐stand) in a prospective cohort of kidney transplant candidates. We assessed each metric's ability to predict time to the composite outcome of waitlist removal or death, censoring at transplant. We built time‐dependent receiver operating characteristic curves and calculated the area under the curve [AUC(t)] at 1 year, using bootstrapping for internal validation. In 199 patients followed for a median of 346 days, 41 reached the composite endpoint. Lower SF‐36 PF scores were associated with higher risk of waitlist removal/death, with every 10‐point decrease corresponding to a 16% increase in risk. All models showed an AUC(t) of 0.83–0.84 that did not contract substantially after internal validation. Among kidney transplant candidates, SF‐36 PF, obtainable remotely, can help to stratify the risk of waitlist removal or death, and may be used as a screening tool for poor physical functioning in ongoing candidate evaluation, particularly where travel, increasing patient volume, or other restrictions challenge in‐person assessment.

Barriers to kidney transplantation in ESKD

Kidney transplantation is the ideal treatment option for patients with end-stage kidney disease (ESKD). Since there is clear mortality benefit to receiving a transplant regardless of comorbidities and age, the gold standard of care should focus on attaining kidney transplantation and minimizing, or better yet eliminating, time on dialysis. Unfortunately, only a small percentage of patients with ESKD receive a kidney transplant. Several barriers to kidney transplantation have been identified. Barriers can largely be grouped into three categories: patient-related, physician/provider-related, and system-related. Several barriers fall into multiple categories and play a role at various levels within the healthcare system. Acknowledging and understanding these barriers will allow transplant centers and dialysis facilities to make the necessary interventions to mitigate these disparities, optimize the transplant evaluation process, and improve patient outcomes. This review will discuss these barriers and potential interventions to increase access to kidney transplantation.

Longer Distance From Dialysis Facility to Transplant Center Is Associated With Lower Access to Kidney Transplantation

Rates of kidney transplantation vary substantially across dialysis facilities in the United States. Whether distance between the dialysis facility and transplant center associates with variations in transplantation rates has not been examined.