Racial differences in outcomes of the evaluation of potential live kidney donors: a retrospective cohort study

Sex/Gender Disparities in Preemptive Referrals for Kidney Transplantation

Introduction

Sex/gender inequities persist in access to kidney transplantation. Whether differences in preemptive referral (i.e., referral before dialysis start) explain this inequity remains unknown.

Methods

All adults (aged 18-79 years; N = 44,204) initiating kidney replacement therapy (KRT; dialysis or transplant) in Georgia (GA), North Carolina (NC), or South Carolina (SC) between 2015 and 2019 were identified from the United States Renal Data System (USRDS). Individuals were linked to the Early Steps to Kidney Transplant Access Registry (E-STAR) to obtain data on preemptive referral and followed-up with through November 13, 2020, for outcomes of waitlisting and living donor transplant. Logistic regression assessed the association between sex/gender and likelihood of preemptive referral among all KRT patients. Cox-proportional hazards assessed the association between sex/gender and waitlisting or living donor among preemptively referred patients.

Results

Overall, men and women were similarly likely to be preemptively referred (odds ratio [OR]: 0.99 [0.95-1.04]). Preemptively referred women (vs. men) were, on average, younger and with fewer comorbidities. There were no sex/gender differences in waitlisting once patients were preemptively referred (hazard ratio [HR]: 0.97 [0.91-1.03]); however, women (vs. men) who were preemptively referred remained 25% (HR: 0.75 [0.66-0.86]) less likely to receive a living donor transplant.

Conclusion

In the Southeast US, men and women initiating KRT are similarly likely to be preemptively referred for a kidney transplant, and this appears, at least in part, to mitigate known sex/gender inequities in access to waitlisting, but not living donor transplant. Despite this, preemptively referred women, on average, had a more favorable medical profile relative to preemptively referred men.

Dialysis Patients' Social Networks and Living Donation Offers

Rationale & Objective

Most living kidney donors are members of a hemodialysis patient's social network. Network members are divided into core members, those strongly connected to the patient and other members; and peripheral members, those weakly connected to the patient and other members. We identify how many hemodialysis patients' network members offered to become kidney donors, whether these offers were from core or peripheral network members, and whose offers the patients accepted.

Study Design

A cross-sectional interviewer-administered hemodialysis patient social network survey.

Setting & Participants

Prevalent hemodialysis patients in 2 facilities.

Predictors

Network size and constraint, a donation from a peripheral network member.

Outcomes

Number of living donor offers, accepting an offer.

Analytical Approach

We performed egocentric network analyses for all participants. Poisson regression models evaluated associations between network measures and number of offers. Logistic regression models determined the associations between network factors and accepting a donation offer.

Results

The mean age of the 106 participants was 60 years. Forty-five percent were female, and 75% self-identified as Black. Fifty-two percent of participants received at least one living donor offer (range 1-6); 42% of the offers were from peripheral members. Participants with larger networks received more offers (incident rate ratio [IRR], 1.26; 95% CI, 1.12-1.42; P = 0.001), including networks with more peripheral members (constraint, IRR, 0.97; 95% CI, 0.96-0.98; P < 0.001). Participants who received a peripheral member offer had 3.6 times greater odds of accepting an offer (OR, 3.56; 95% CI, 1.15-10.8; P = 0.02) than those who did not receive a peripheral member offer.

Limitations

A small sample of only hemodialysis patients.

Conclusions

Most participants received at least one living donor offer, often from peripheral network members. Future living donor interventions should focus on both core and peripheral network members.

Living kidney donation in a developing country

BACKGROUND

Living kidney donation has been advocated as a means to ameliorate the chronic shortage of organs for transplantation. Significant rates of comorbidity and familial risk for kidney disease may limit this approach in the local context; there is currently limited data describing living donation in Africa.

METHODS

We assessed reasons for non-donation and outcomes following donation in a cohort of 1208 ethnically diverse potential living donors evaluated over a 32-year period at a single transplant centre in South Africa.

RESULTS

Medical contraindications were the commonest reason for donor exclusion. Black donors were more frequently excluded (52.1% vs. 39.3%; p<0.001), particularly for medical contraindications (44% vs. 35%; p<0.001); 298 donors proceeded to donor nephrectomy (24.7%). Although no donor required kidney replacement therapy, an estimated glomerular filtration rate below 60 ml/min/1.73 m2 was recorded in 27% of donors at a median follow-up of 3.7 years, new onset albuminuria >300 mg/day was observed in 4%, and 12.8% developed new-onset hypertension. Black ethnicity was not associated with an increased risk of adverse post-donation outcomes.

CONCLUSION

This study highlights the difficulties of pursuing live donation in a population with significant medical comorbidity, but provides reassurance of the safety of the procedure in carefully selected donors in the developing world.

Sex and Gender Differences in Kidney Transplantation

Sex and gender often are used interchangeably, but are two distinct entities, with sex being the biological attribute and gender including the social, psychological, and cultural aspects of one's identity. Kidney transplantation has been proven to be the best treatment for end-stage kidney disease, improving both quality of life and life-expectancy for most patients. However, gender disparities in access to and outcomes of kidney transplantation remain despite the plethora of evidence showing the advantages of kidney transplantation to our patients. Data have shown that women are less likely to be waitlisted for a kidney transplant and to receive a deceased donor or a living donor kidney. On the other hand, women are more likely than men to become living kidney donors. Although some state the latter is the result of the female gender to nurture and care for loved ones, others believe this observation is because women often are incompatible with their spouse or child because pregnancy is a strong sensitizing event, which stems from the biological rather than the social differences between the sexes. Influence of sex and gender is not limited to access to kidney transplantation, but rather exist in other areas of transplant medicine, such as the difference observed in transplant outcomes between the sexes, variability in immunosuppression metabolism, and even in more contemporary areas such as recent data showing sex-based differences in outcomes of kidney transplant recipients with coronavirus disease-2019, with males having an increased incidence of acute kidney injury and death.

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.

Care of international living kidney donor candidates in the United States: A survey of contemporary experience, practice, and challenges

The evaluation and care of non-US citizen, non-US residents who wish to come to the United States to serve as international living kidney donors (ILKDs) can pose unique challenges. We surveyed US transplant programs to better understand practices related to ILKD care. We distributed the survey by email and professional society list-servs (Fall 2018, assessing 2017 experience). Eighty-five programs responded (36.8% program response rate), of which 80 considered ILKD candidates. Only 18 programs had written protocols for ILKD evaluation. Programs had a median of 3 (range: 0,75) ILKD candidates who initiated contact during the year, from origin countries spanning 6 continents. Fewer (median: 1, range: 0,25) were approved for donation. Program-reported reasons for not completing ILKD evaluations included visa barriers (58.6%), inability to complete evaluation (34.3%), concerns regarding follow-up (31.4%) or other healthcare access (28.6%), and financial impacts (21.4%). Programs that did not evaluate ILKDs reported similar concerns. Staff time required to evaluate ILKDs was estimated as 1.5-to-3-times (47.9%) or >3-times (32.9%) that needed for domestic candidates. Among programs accepting ILKDs, on average 55% reported successful completion of 1-year follow-up. ILKD evaluation is a resource-intensive process with variable outcomes. Planning and commitment are necessary to care for this unique candidate group.

The Role of Community Pharmacists in the Detection of Clinically Relevant Drug-Related Problems in Chronic Kidney Disease Patients

Community pharmacists (CPs) have traditionally had limited access to patients’ estimated glomerular filtration rate (eGFR) during the medication-dispensing process. The increasing access to shared electronic health records is making eGFR available, but the skills needed to detect and manage clinically relevant drug-related problems (DRPs) are poorly documented. The primary objective of this study was to investigate the role of CPs in the medication-dispensation process for elderly patients with renal impairment. A total of 70 CPs participated in this 6 month study. Community pharmacists asked all patients ≥65 years to bring their laboratory test values for the next medication-dispensing process. Drug-related problem detection rates were compared between CPs (prospective period) and expert pharmacists (retrospectively). The clinical relevance of each DRP was assessed by nephrologists and general practitioners using an appropriate tool. Community pharmacists recruited n = 442 patients with eGFR < 60 mL/min/1.73 m² and detected n = 99 DRPs, whereas expert pharmacists detected n = 184 DRPs. The most frequently detected DRPs were dosage problems and contraindications. According to assessment by clinicians, CPs and expert pharmacists identified 54.0% and 84.7% of clinically relevant DRPs, respectively. This study suggests a positive impact of the systematic availability of eGFR to CPs on the detection of several DRPs with clinical relevance.

Enhanced Advocacy and Health Systems Training Through Patient Navigation Increases Access to Living-donor Kidney Transplantation

BACKGROUND

To date, no living donation program has simultaneously addressed the needs of both transplant candidates and living donors by separating the advocacy role from the candidate and improving potential donor comfort with the evaluation process. We hypothesized that the development of a novel program designed to promote both advocacy and systems training among transplant candidates and their potential living kidney donors would result in sustained increases in living-donor kidney transplantation (LDKT). To this end, we developed and implemented a Living Donor Navigator (LDN) Program at the University of Alabama at Birmingham.

METHODS

We included adult patients awaiting kidney-only transplant in a retrospective cohort analysis. Using time-varying Cox proportional hazards regression, we explored likelihood of living donor screening and approval by participation in the LDN program.

RESULTS

There were 56 LDN participants and 1948 nonparticipants (standard of care). LDN was associated with a 9-fold increased likelihood of living donor screenings (adjusted hazard ratio, 9.27; 95% confidence interval, 5.97-14.41, P < 0.001) and a 7-fold increased likelihood of having an approved living donor (adjusted hazard ratio, 7.74; 95% confidence interval, 3.54-16.93; P < 0.001) compared with the standard of care. Analyses by participant race demonstrated higher likelihood of screened donors and a similar likelihood of having an approved donor among African Americans compared with Caucasians.

CONCLUSIONS

These data suggest that both advocacy and systems training are needed to increase actual LDKT rates, and that LDN programs may mitigate existing racial disparities in access to LDKT.

Bariatric surgery for prospective living kidney donors with obesity?

The obesity epidemic has gripped the transplant community. With nearly 40% of adults in the United States being obese (BMI ≥30 kg/m² ) and 20% being morbidly obese (BMI ≥35 kg/m² ), the implications for both donors and recipients of solid organs continue to grow.¹ Nowhere is this more impactful than the candidacy of living kidney donors (LKDs). As increasing numbers of obese adults present for LKD consideration and evidence of inferior outcomes among obese LKDs grows, transplant surgeons will become progressively challenged by how to manage these patients in the clinic. Therefore, we offer this Personal Viewpoint to the transplant surgery community in order to review the current impact of obesity on living kidney donation, highlight what weight-loss interventions have already been attempted, and discuss the role that referral for weight-loss interventions including bariatric surgery might have going forward.

Why Potential Living Kidney Donors Do Not Proceed for Donation: A Single-Center Experience

BACKGROUND

Living donor kidney transplantation is the best type of renal replacement therapy. However, large numbers of potential living kidney donors (LKDs) are declined because of various reasons. The aim of this study is to define and quantify the reasons for declining potential LKDs.

METHODS

All potential LKDs evaluated at our center between September 2008 and December 2016 were reviewed. Data were collected from the electronic database.

RESULTS

A total of 2090 potential LKDs were evaluated, with an average age of 32 years (range, 18-67 years) and men constituting 72.6%. A total of 675 (32.3%) were accepted for donor nephrectomy. Living kidney donation did not proceed in 830 (39.7%): 661 (79.6%) because of donor-related reasons and 169 (20.4%) because of recipient-related reasons. Donor-related reasons included medical contraindications (61.7%), immunological barriers (23.1%), surgical contraindications (7.9%), and psychosocial reasons (7.3%). A total of 585 (28.0%) potential LKDs voluntarily withdrew themselves at variable time points during the evaluation process, even after being accepted for donation. Male and young (18-35 years) potential LKDs were more likely to withdraw compared with female and older (>35 years) potential LKDs (34.3% vs 11.4%, P < .005 and 29.6% vs 24.5%, P = .02, respectively).

CONCLUSIONS

Despite the large number of potential LKDs, medically complex donors are increasing, and a significant proportion decided to withdraw at some point during the evaluation process. The latter highlights the need to increase public awareness about living donation, to perform more careful initial screening and targeted educational programs, and to provide continuous support for potential LKDs.

Population Health, Ethnicity, and Rate of Living Donor Kidney Transplantation

BACKGROUND

Living donor kidney transplantation has declined in the United States since 2004, but the relationship between population characteristics and rate of living donation is unknown. The goal of our study was to use data on general population health and socioeconomic status to investigate the association with living donation.

METHODS

This cross-sectional, ecological study used population health and socioeconomic status data from the CDC Behavioral Risk Factor Surveillance System to investigate the association with living donation. Transplant centers performing 10 or greater kidney transplants reported to the Scientific Registry of Transplant Recipients in 2015 were included. Center rate of living donation was defined as the proportion of all kidney transplants performed at a center that were from living donors.

RESULTS

In a linear mixed-effects model, a composite index of health and socioeconomic status factors was negatively associated with living donation, with a rate of living donation that was on average 7.3 percentage points lower among centers in areas with more comorbid disease and poorer socioeconomic status (95% confidence interval, -12.2 to -2.3, P = 0.004). Transplant centers in areas with higher prevalence of minorities had a rate of living donation that was 7.1 percentage points lower than centers with fewer minorities (95% confidence interval, -11.8 to -2.3, P = 0.004).

CONCLUSIONS

Center-level variation in living donation was associated with population characteristics and minority prevalence. Further examination of these factors in the context of patient and center-level barriers to living donation is warranted.

The Efficiency of Evaluating Candidates for Living Kidney Donation: A Scoping Review

Supplemental digital content is available in the text.

Introduction

The process of evaluating candidates for living kidney donation can be inefficient. A structured review of existing information on this topic can provide a necessary foundation for quality improvement.

Methods

We conducted a scoping review to map the published literature to different themes related to an efficient donor candidate evaluation. We reviewed the websites of living donor programs to describe information provided to candidates about the nature and length of the evaluation process.

Results

We reviewed of 273 published articles and 296 websites. Surveys of living donor programs show variability in donor evaluation protocols. Computed tomography (a routinely done test for all successful candidates) may be used to assess split renal volume instead of nuclear renography when the 2 kidneys differ in size. Depending on the candidate’s estimated glomerular filtration rate, a nuclear medicine scan for measured glomerular filtration rate may not be needed. When reported, the time to complete the evaluation varied from 3 months to over a year. The potential for undesirable outcomes was reported in 23 studies, including missed opportunities for living donation and/or preemptive transplants. According to living donor websites, programs generally evaluate 1 candidate at a time when multiple come forward for assessment, and few programs describe completing most of the evaluation in a single in-person visit.

Conclusions

Data on the efficiency of the living donor evaluation are limited. Future efforts can better define, collect, and report indicators of an efficient living donor evaluation to promote quality improvement and better patient outcomes.

Racial differences in completion of the living kidney donor evaluation process

Racial disparities in living donor kidney transplantation (LDKT) persist but the most effective target to eliminate these disparities remains unknown. One potential target could be delays during completion of the live donor evaluation process. We studied racial differences in progression through the evaluation process for 247 African American (AA) and 664 non-AA living donor candidates at our center between January 2011 and March 2015. AA candidates were more likely to be obese (38% vs 22%: P < .001), biologically related (66% vs 44%: P < .001), and live ≤50 miles from the center (64% vs 37%: P < .001) than non-AAs. Even after adjusting for these differences, AAs were less likely to progress from referral to donation (aHR for AA vs non-AA: 0.26 0.47 0.83; P = .01). We then assessed racial differences in completion of each step of the evaluation process and found disparities in progression from medical screening to in-person evaluation (aHR: 0.41 0.620.94; P = .02) and from clearance to donation (aHR: 0.28 0.510.91; P = .02), compared with from referral to medical screening (aHR: 0.78 1.021.33; P = .95) and from in-person evaluation to clearance (aHR: 0.59 0.931.44; P = .54). Delays may be a manifestation of the transplant candidate's social network, thus, targeted efforts to optimize networks for identification of donor candidates may help address LDKT disparities.

Factors associated with perceived donation-related financial burden among living kidney donors

The perception of living kidney donation-related financial burden affects willingness to donate and the experience of donation, yet no existing tools identify donors who are at higher risk of perceived financial burden. We sought to identify characteristics that predicted higher risk of perceived financial burden. We surveyed 51 living kidney donors (LKDs) who donated from 01/2015 to 3/2016 about socioeconomic characteristics, predonation cost concerns, and perceived financial burden. We tested associations between both self-reported and ZIP code-level characteristics and perceived burden using Fisher's exact test and bivariate modified Poisson regression. Donors who perceived donation-related financial burden were less likely to have an income above their ZIP code median (14% vs. 72%, P = .006); however, they were more likely than donors who did not perceive burden to rent their home (57% vs. 16%, P = .03), have an income <$60 000 (86% vs. 20%, P = .002), or have had predonation cost concerns (43% vs. 7%, P = .03). Perceived financial burden was 3.6-fold as likely among those with predonation cost concerns and 10.6-fold as likely for those with incomes <$60 000. Collecting socioeconomic characteristics and asking about donation-related cost concerns prior to donation might allow transplant centers to target financial support interventions toward potential donors at higher risk of perceiving donation-related financial burden.

Opting out: a single-centre pilot study assessing the reasons for and the psychosocial impact of withdrawing from living kidney donor evaluation

Understanding why individuals opt out of living donation is crucial to enhancing protections for all living donors and to identify modifiable barriers to donation. We developed an ethical approach to conducting research on individuals who opted out of living kidney donation and applied it in a small-scale qualitative study at one US transplant centre. The seven study participants (64% response rate) had varied reasons for opting out, the most prominent of which was concern about the financial burden from lost wages during the postoperative period. Several reported feeling alone during their decision-making process. Although no participants used an alibi, a centre-provided statement of non-eligibility to donate, all believed that centres should offer alibis to help preserve donor autonomy. Given the complexity of participants' decisions and the emotions they experienced before and after deciding not to donate, we suggest approaches for independent living donor advocates to support this population. This study demonstrates that research on individuals who opt out of donation is feasible and yields valuable insight into methods to improve the evaluation experience for potential living donors.

Characteristics and Evaluation of Geographically Distant vs Geographically Nearby Living Kidney Donors

BACKGROUND

Living donor kidney transplant (LDKT) can be impeded by multiple barriers. One possible barrier to LDKT is a large physical distance between the living donor's home residence and the procuring transplant center.

METHODS

We performed a retrospective, single-center study of living kidney donors in the United States who were geographically distant (residing ≥150 miles) from our transplant center. Each distant donor was matched to 4 geographically nearby donors (<150 miles from our center) as controls.

RESULTS

From 2007 to 2010, of 429 live kidney donors, 55 (12.8%) were geographically distant. Black donors composed a higher proportion of geographically distant vs nearby donors (34.6% vs 15.5%), whereas Hispanic and Asian donors composed a lower proportion (P = .001). Distant vs nearby donors had similar median times from donor referral to actual donation (165 vs 161 days, P = .81). The geographically distant donors lived a median of 703 miles (25% to 75% range, 244 to 1072) from our center and 21.2 miles (25% to 75% range, 9.8 to 49.7) from the nearest kidney transplant center. The proportion of geographically distant donors who had their physician evaluation (21.6%), psychosocial evaluation (21.6%), or computed tomography angiogram (29.4%) performed close to home, rather than at our center, was low.

CONCLUSIONS

Many geographically distant donors live close to transplant centers other than the procuring transplant center, but few of these donors perform parts of their donor evaluation at these closer centers. Black donors comprise a large proportion of geographically distant donors. The evaluation of geographically distant donors, especially among minorities, warrants further study.

The decline in living kidney donation in the United States: random variation or cause for concern?

The annual number of living kidney donors in the United States peaked at 6647 in 2004. The preceding decade saw a 120% increase in living kidney donation. However, since 2004, living kidney donation has declined in all but 1 year, resulting in a 13% decline in the annual number of living kidney donors from 2004 to 2011. The proportional decline in living kidney donation has been more pronounced among men, blacks, younger adults, siblings, and parents. In this article, we explore several possible explanations for the decline in living kidney donation, including an increase in medical unsuitability, an aging transplant patient population, financial disincentives, public policies, and shifting practice patterns, among others. We conclude that the decline in living donation is not merely reflective of random variation but one that warrants action by the transplant centers, the broader transplant community, and the state and national governments.