Variation of ApoL1 Testing Practices for Living Kidney Donors

Evaluating ApoL1 Genetic Testing Policy Options for Transplant Centers: A Delphi Consensus Panel Project with Stakeholders

BACKGROUND

Apolipoprotein L1 (ApoL1) variants G1 and G2 are associated with a higher risk of kidney disease. ApoL1 risk variants are predominantly seen in individuals with sub-Saharan African ancestry. In most transplant centers, potential organ donors are being selectively genetically tested for ApoL1 risk variants. Transplant programs have highly variable ApoL1 testing practices and need guidance on essential ApoL1 clinical policy questions.

METHODS

We conducted a Delphi consensus panel focused on ApoL1 clinical policy questions, including who gets tested, who decides whether testing occurs, how test results are shared, who receives test results, and how test results are used. A total of 27 panelists across seven stakeholder groups participated: living kidney donors ( n =4), deceased donor family members ( n =3), recipients of a deceased donor kidney ( n =4), recipients of a living donor kidney ( n =4), nephrologists ( n =4), transplant surgeons ( n =4), and genetic counselors ( n =4). Nineteen panelists (70%) identified as Black. The Delphi panel process involved two rounds of educational webinars and three rounds of surveys administered to panelists, who were asked to indicate whether they support, could live with, or oppose each policy option.

RESULTS

The panel reached consensus on one or more acceptable policy options for each clinical policy question; panelists supported 18 policy options and opposed 15. Key elements of consensus include the following: ask potential donors about African ancestry rather than race; make testing decisions only after discussion with donors; encourage disclosure of test results to blood relatives and organ recipients but do not require it; use test results to inform decision making, but never for unilateral decisions by transplant programs.

CONCLUSIONS

The panel generally supported policy options involving discussion and shared decision making among patients, donors, and family stakeholders. There was general opposition to unilateral decision making and prohibiting donation altogether.

Conflating race and ancestry: Tracing decision points about population descriptors over the precision medicine research life course

Responding to calls for human genomics to shift away from the use of race, genomic investigators are coalescing around the possibility of using genetic ancestry. This shift has renewed questions about the use of social and genetic concepts of difference in precision medicine research (PMR). Drawing from qualitative data on five PMR projects, we illustrate negotiations within and between research teams as genomic investigators deliberate on the relevance of race and genetic ancestry for different analyses and contexts. We highlight how concepts of both social and genetic difference are embedded within and travel through research practices, and identify multiple points across the research life course at which conceptual slippage and conflation between race and genetic ancestry occur. We argue that moving beyond race will require PMR investigators to confront the entrenched ways in which race is built into research practices and biomedical infrastructures.

Implementation of a culturally competent APOL1 genetic testing programme into living donor evaluation: A two-site, non-randomised, pre-post trial design

INTRODUCTION

While living donor (LD) kidney transplantation is the optimal treatment for patients with kidney failure, LDs assume a higher risk of future kidney failure themselves. LDs of African ancestry have an even greater risk of kidney failure post-donation than White LDs. Because evidence suggests that Apolipoprotein L1 (APOL1) risk variants contribute to this greater risk, transplant nephrologists are increasingly using APOL1 genetic testing to evaluate LD candidates of African ancestry. However, nephrologists do not consistently perform genetic counselling with LD candidates about APOL1 due to a lack of knowledge and skill in counselling. Without proper counselling, APOL1 testing will magnify LD candidates' decisional conflict about donating, jeopardising their informed consent. Given cultural concerns about genetic testing among people of African ancestry, protecting LD candidates' safety is essential to improve informed decisions about donating. Clinical 'chatbots', mobile apps that provide genetic information to patients, can improve informed treatment decisions. No chatbot on APOL1 is available and no nephrologist training programmes are available to provide culturally competent counselling to LDs about APOL1. Given the shortage of genetic counsellors, increasing nephrologists' genetic literacy is critical to integrating genetic testing into practice.

METHODS AND ANALYSIS

Using a non-randomised, pre-post trial design in two transplant centres (Chicago, IL, and Washington, DC), we will evaluate the effectiveness of culturally competent APOL1 testing, chatbot and counselling on LD candidates' decisional conflict about donating, preparedness for decision-making, willingness to donate and satisfaction with informed consent and longitudinally evaluate the implementation of this intervention into clinical practice using the Reach, Effectiveness, Adoption, Implementation and Maintenance framework.

ETHICS AND DISSEMINATION

This study will create a model for APOL1 testing of LDs of African ancestry, which can be implemented nationally via implementation science approaches. APOL1 will serve as a model for integrating culturally competent genetic testing into transplant and other practices to improve informed consent. This study involves human participants and was approved by Northwestern University IRB (STU00214038). Participants gave informed consent to participate in the study before taking part.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT04910867. Registered 8 May 2021, https://register.

CLINICALTRIALS

gov/prs/app/action/SelectProtocol?sid=S000AWZ6&selectaction=Edit&uid=U0001PPF&ts=7&cx=-8jv7m2 ClinicalTrials.gov Identifier: NCT04999436. Registered 5 November 2021, https://register.

CLINICALTRIALS

gov/prs/app/action/SelectProtocol?sid=S000AYWW&selectaction=Edit&uid=U0001PPF&ts=11&cx=9tny7v.

Genetic evaluation of living kidney donor candidates: A review and recommendations for best practices

The growing accessibility and falling costs of genetic sequencing techniques has expanded the utilization of genetic testing in clinical practice. For living kidney donation, genetic evaluation has been increasingly used to identify genetic kidney disease in potential candidates, especially in those of younger ages. However, genetic testing on asymptomatic living kidney donors remains fraught with many challenges and uncertainties. Not all transplant practitioners are aware of the limitations of genetic testing, are comfortable with selecting testing methods, comprehending test results, or providing counsel, and many do not have access to a renal genetic counselor or a clinical geneticist. Although genetic testing can be a valuable tool in living kidney donor evaluation, its overall benefit in donor evaluation has not been demonstrated and it can also lead to confusion, inappropriate donor exclusion, or misleading reassurance. Until more published data become available, this practice resource should provide guidance for centers and transplant practitioners on the responsible use of genetic testing in the evaluation of living kidney donor candidates.

Attitudes and beliefs regarding race-targeted genetic testing of Black people: A systematic review

Geographical ancestry has been associated with an increased risk of various genetic conditions. Race and ethnicity often have been used as proxies for geographical ancestry. Despite numerous problems associated with the crude reliance on race and ethnicity as proxies for geographical ancestry, some genetic testing in the clinical, research, and employment settings has been and continues to be race- or ethnicity-based. Race-based or race-targeted genetic testing refers to genetic testing offered only or primarily to people of particular racial or ethnic groups because of presumed differences among groups. One current example is APOL1 testing of Black kidney donors. Race-based genetic testing raises numerous ethical and policy questions. Given the ongoing reliance on the Black race in genetic testing, it is important to understand the views of people who identify as Black or are identified as Black (including African American, Afro-Caribbean, and Hispanic Black) regarding race-based genetic testing that targets Black people because of their race. We conducted a systematic review of studies and reports of stakeholder-engaged projects that examined how people who identify as or are identified as Black perceive genetic testing that specifically presumes genetic differences exist among racial groups or uses race as a surrogate for ancestral genetic variation and targets Black people. Our review identified 14 studies that explicitly studied this question and another 13 that implicitly or tacitly studied this matter. We found four main factors that contribute to a positive attitude toward race-targeted genetic testing (facilitators) and eight main factors that are associated with concerns regarding race-targeted genetic testing (barriers). This review fills an important gap. These findings should inform future genetic research and the policies and practices developed in clinical, research, public health, or other settings regarding genetic testing.

The evolving role of diagnostic genomics in kidney transplantation

Monogenic forms of heritable kidney disease account for a significant proportion of chronic kidney disease (CKD) across both pediatric and adult patient populations and up to 11% of patients under 40 years reaching end-stage kidney failure (KF) and awaiting kidney transplant. Diagnostic genomics in the field of nephrology is ever evolving and now plays an important role in assessment and management of kidney transplant recipients and their related donor pairs. Genomic testing can help identify the cause of KF in kidney transplant recipients and assist in prognostication around graft survival and rate of recurrence of primary kidney disease. If a gene variant has been identified in the recipient, at-risk related donors can be assessed for the same and excluded if affected. This paper aims to address the indications for genomic testing in the context for kidney transplantation, the technologies available for testing, the conditions and groups in which testing should be most often considered, and the role for the renal genetics multidisciplinary team in this process.

Apolipoprotein L1 Opinions of African American Living Kidney Donors, Kidney Transplant Patients, and Nonpatients

INTRODUCTION

The discovery of apolipoprotein L1 (ApoL1) has raised important ethical and clinical questions about genetic testing in the context of living and deceased kidney donation. Largely missing from this discussion are the perspectives of those African Americans (AA) most likely to be impacted by ApoL1 testing.

METHODS

We surveyed 331 AA potential and former living kidney donors (LKDs), kidney transplant candidates and recipients, and nonpatients at three United States transplant programs about their ApoL1 testing attitudes.

RESULTS

Overall, 72% felt that transplant programs should offer ApoL1 testing to AA potential LKDs. If a potential LKD has the high-risk genotype, 79% felt that the LKD should be allowed to make their own donation decision or participate in shared decision-making with transplant doctors. More than half of the potential LKDs (58%) would undergo ApoL1 testing and 81% of former LKDs would take the test now if offered. Most transplant candidates expressed a low likelihood of accepting a kidney from a LKD (79%) or a deceased donor (67%) with the high-risk genotype.

CONCLUSIONS

There is strong support among LKDs and transplant patients for ApoL1 testing when evaluating potential kidney donors of African ancestry. Inclusion of AA stakeholders in developing guidelines and educational programs for ApoL1 testing is critical.

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.

Impact of education on APOL1 testing attitudes among prospective living kidney donors

It is unknown how providing prospective living donors with information about APOL1, including the benefits and drawbacks of testing, influences their desire for testing. In this study, we surveyed 102 participants with self-reported African ancestry and positive family history of kidney disease, recruited from our nephrology waiting room. We assessed views on APOL1 testing before and after presentation of a set of potential benefits and drawbacks of testing and quantified the self-reported level of influence individual benefits and drawbacks had on participants' desire for testing in the proposed context of living donation. The majority of participants (92%) were aware of organ donation and more than half (56%) had considered living donation. And though we found no significant change in response following presentation of the potential benefits and the drawbacks of APOL1 testing by study end significance, across all participants, "becoming aware of the potential risk of kidney disease among your immediate family" was the benefit with the highest mean influence (3.3±1.4), while the drawback with the highest mean influence (2.9±1.5) was "some transplant centers may not allow you to donate to a loved one". This study provides insights into the priorities of prospective living donors and suggests concern for how the information affects family members may strongly influence desires for testing. It also highlights the need for greater community engagement to gain a deeper understanding of the priorities that influence decision making on APOL1 testing.

Ignorance is Not Bliss: The Case for Comprehensive Reproductive Counseling for Women with Chronic Kidney Disease

The bioethics literature has paid little attention to matters of informed reproductive decision-making among women of childbearing age who have chronic kidney disease (CKD), including women who are on dialysis or women who have had a kidney transplant. Women with CKD receive inconsistent and, sometimes, inadequate reproductive counseling, particularly with respect to information about pursuing pregnancy. We identify four factors that might contribute to inadequate and inconsistent reproductive counseling. We argue that women with CKD should receive comprehensive reproductive counseling, including information about the possibility of pursuing pregnancy, and that more rigorous research on pregnancy in women with CKD, including women on dialysis or who have received a kidney transplant, is warranted to improve informed reproductive decision making in this population.

Gender and race/ethnicity differences in living kidney donor demographics: Preference or disparity?

In the United States, women are over-represented and Blacks are under-represented as living kidney donors. A traditional bioethics approach would state that as long as living donors believe that the benefits of participation outweigh the risks and harms (beneficence) and they give a voluntary and informed consent, then the demographics reflect a mere difference in preferences. Such an analysis, however, ignores the social, economic and cultural determinants as well as various forms of structural discrimination (e.g., racism, sexism) that may imply that the distribution is less voluntary than may appear initially. The distribution also raises justice concerns regarding the fair recruitment and selection of living donors. We examine the differences in living kidney donor demographics using a vulnerabilities analysis and argue that these gender and racial differences may not reflect mere preferences, but rather, serious justice concerns that need to be addressed at both the individual and systems level.

Diagnosis, Education, and Care of Patients with APOL1-Associated Nephropathy: A Delphi Consensus and Systematic Review

BACKGROUND

APOL1 variants contribute to the markedly higher incidence of ESKD in Blacks compared with Whites. Genetic testing for these variants in patients with African ancestry who have nephropathy is uncommon, and no specific treatment or management protocol for APOL1-associated nephropathy currently exists.

METHODS

A multidisciplinary, racially diverse group of 14 experts and patient advocates participated in a Delphi consensus process to establish practical guidance for clinicians caring for patients who may have APOL1-associated nephropathy. Consensus group members took part in three anonymous voting rounds to develop consensus statements relating to the following: (1) counseling, genotyping, and diagnosis; (2) disease awareness and education; and (3) a vision for management of APOL1-associated nephropathy in a future when treatment is available. A systematic literature search of the MEDLINE and Embase databases was conducted to identify relevant evidence published from January 1, 2009 to July 14, 2020.

RESULTS

The consensus group agreed on 55 consensus statements covering such topics as demographic and clinical factors that suggest a patient has APOL1-associated nephropathy, as well as key considerations for counseling, testing, and diagnosis in current clinical practice. They achieved consensus on the need to increase awareness among key stakeholders of racial health disparities in kidney disease and of APOL1-associated nephropathy and on features of a successful education program to raise awareness among the patient community. The group also highlighted the unmet need for a specific treatment and agreed on best practice for management of these patients should a treatment become available.

CONCLUSIONS

A multidisciplinary group of experts and patient advocates defined consensus-based guidance on the care of patients who may have APOL1-associated nephropathy.

Association Between Donor-Recipient Biological Relationship and Allograft Outcomes After Living Donor Kidney Transplant

IMPORTANCE

The proportion of living donor kidney transplants from donors unrelated to their recipients is increasing in the US.

OBJECTIVE

To examine the association between donor-recipient biological relationship and allograft survival after living donor kidney transplant.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cohort study used Organ Procurement and Transplantation Network data on US adult living donor kidney transplants (n = 86 154) performed from January 1, 2000, to December 31, 2014, excluding cases in which recipients previously received a kidney transplant (n = 10 342) or key data were missing (n = 2832). Last follow-up was March 20, 2020.

EXPOSURES

Donor-recipient biological relationship.

MAIN OUTCOMES AND MEASURES

The primary outcome was death-censored allograft failure. Univariate and multivariable time-to-event analyses were performed for death-censored allograft failure for the overall cohort, then separately for recipients with and without primary diagnoses of cystic kidney disease and for transplants from African American and non-African American donors.

RESULTS

Among the 72 980 transplant donor and recipients included in the study (median donor age, 41 years; interquartile range [IQR], 32-50 years; 43 990 [60%] female; 50 014 [69%] White), 43 174 (59%) donors and recipients were biologically related and 29 806 (41%) were unrelated. Donors related to their recipients were younger (median [IQR] age, 39 [31-48] vs 44 [35-52] years) and less likely to be female (24 848 [58%] vs 19 142 [64%]) or White (26 933 [62%] vs 23 081 [77%]). Recipients related to their donors were younger (median [IQR] age, 48 [34-58] vs 50 [40-58] years), more likely to be female (18 035 [42%] vs 10 530 [35%]), and less likely to have cystic kidney disease (2530 [6%] vs 4600 [15%]). Related pairs had fewer HLA mismatches overall (median [IQR], 3 [2-3] vs 5 [4-5]). After adjustment for HLA mismatches, donor and recipient characteristics, and transplant era, donor-recipient biological relationship was associated with higher death-censored allograft failure (hazard ratio, 1.05; 95% CI, 1.01-1.10; P = .03). When stratified by primary disease, this association persisted only for recipients without cystic kidney disease. When stratified by donor race, this association persisted only for transplants from African American donors.

CONCLUSIONS AND RELEVANCE

In this cohort study, living donor kidney transplants from donors biologically related to their recipients had higher rates of allograft failure than transplants from donors unrelated to their recipients after HLA matching was accounted for. Further study is needed to determine which genetic or socioenvironmental factors are associated with this finding.

Attitudes and Practices of Australian Nephrologists Toward Implementation of Clinical Genomics

Introduction

Genomic testing is becoming widely available as a diagnostic tool, although widespread implementation is not yet established in nephrology.

Methods

An anonymous electronic survey was administered to investigate experience and confidence with genomic tests, perceived clinical utility of genomic services, preferences for service delivery models, and readiness for implementation among nephrologists. Questions were guided by a comprehensive literature review and published tools, including a validated theoretical framework for implementation of genomic medicine: Consolidated Framework for Implementation Research (CFIR).

Results

Responses were received from 224 clinicians, of which 172 were eligible for analysis. Most clinicians (132 [76%]) had referred at least one patient to a genetics clinic. Despite most clinicians (136 [85%]) indicating that they believed genetic testing would be useful, only 39 (23%) indicated they felt confident to use results of genomic testing, with pediatric clinicians feeling more confident compared with adult clinicians (12 of 20 [60%] vs. 27 of 149 [18%]), P < 0.01, Fisher exact). A multidisciplinary renal genetics clinic was the preferred model among clinicians surveyed (98 of 172 [57%]). A key implementation barrier highlighted related to the hospital or organizational culture and/or environment. Specific barriers noted in quantitative and qualitative responses included inadequate staffing, learning resources, and funding.

Conclusions

Our findings suggest support for genomic testing among nephrologists, with a strong preference for a multidisciplinary model (involving a nephrologist, clinical geneticist, and genetic counselor). Broad-ranging interventions are urgently required to shift the current culture and ensure successful implementation of genomics in nephrology, including reducing knowledge gaps, increased funding and resources, disease-specific guidelines, and streamlining of testing processes.

Clinical Applications of Genetic Discoveries in Kidney Transplantation: a Review

Growth in knowledge of the genetics of kidney disease has revealed that significant percentages of patients with diverse types of nephropathy have causative mutations. Genetic testing is poised to play an increasing role in the care of patients with kidney disease. The role of genetic testing in kidney transplantation is not well established. This review will explore the ways in which genetic testing may be applied to improve the care of kidney transplant recipients and donors.