End stage renal disease (ESRD) is among the ten leading causes of death for Americans, and its incidence and prevalence are rising, especially among non-White groups. Kidney transplantation is the most effective treatment option for many Americans, but the number of Americans needing kidneys is currently much larger and rising much faster than current transplant levels. Patients who seek transplants have one of two options: wait for a kidney from a deceased donor to become available, or obtain a transplant from a living kidney donor. Deceased donor kidney transplant levels are projected to grow little over time, constrained by population aging and mortality patterns, but living donation donor kidney transplantation (LDD KT) holds the prospect of substantial growth if healthy population members are willing and able to donate. Unfortunately, there are large and persistent racial and ethnic disparities in LDD KT rates that compound disparities in rates of ESRD. Prior research hypothesizes that differential access to healthy, compatible donors in candidates' social networks may explain racial disparities in usage of LDD KT. However, a limitation of this work is that it focuses on those who are evaluated for donation, not the many members of transplant candidates' social networks who could be evaluated for donation, but are not. We propose a multi-center study to collect novel data on transplant candidates' social networks and to test promising social interventions that could reduce barriers to LDD KT. Based on qualitative interviews and a pilot survey of 72 transplant candidates we previously collected in a large transplant center, we suspect that the differential access hypothesis does not hold, and that there are promising points of social intervention for researchers to reduce racial disparities in LDD KT. These pilot data show large LDD KT underutilization for all candidates, and that Black candidates have access to promising living donors at higher rates than White candidates. Based on these findings, we hypothesize that the primary barrier to eliminating disparities in LDD KT and promoting greater utilization of LDD KT for all groups is social, not biomedical, in origin. In this proposal, we will extend our prior work to develop and test evidence based, randomized social network interventions that will target social barriers to LDD KT and follow up with candidate medical records to evaluate the efficacy of these interventions. Specifically, we will compare a control group of candidates to those assigned to two treatments that we will pilot and test: a) a search intervention where a subset of candidates is coached to approach promising family members that seem to be underutilized based on our pilot data, and b) a rhetorical intervention where we encourage a subset of candidates to use scripts for discussing transplantation with family members that we find to be effective in survey vignette experiments and focus groups. With eighteen month medical records follow up of all candidates and the large amount of data we will obtain on their social networks, we will assess the social barriers that lead to underutilization of LDD KT, how those factors vary by race, and how they can be reduced through promising social network interventions. LDD KT has substantial potential to solve public health challenges around the growing prevalence of ESRD, and the basic and applied knowledge that we will develop as part of this proposal will help to unlock this potential.
This project will evaluate underutilization of living donor donation kidney transplantation (LDD KT) at two large kidney transplant centers and develop and test evidence based, randomized interventions to increase LDD KT and reduce racial disparities in its use. LDD KT is the most promising treatment option to meet the challenges of a rising population of Americans with end stage renal disease (ESRD), but LDD KT rates are not increasing and racial disparities in the use of LDD KT are widening. Prior research has documented that non-white transplant candidates are less likely than white candidates to have family or friends evaluated for LDD KT, and that those evaluated for donation to non-white candidates are less likely to be deemed healthy and compatible enough to donate than those evaluated for white candidates, but it has not examined the full family and social networks in which candidates are embedded in order to determine whether limited access to healthy, compatible donors drives underutilization and racial disparities or whether other social barriers are in operation. This neglect is unfortunate because there are many non-medical interventions that could be tested to increase rates of LDD KT by giving candidates more information about what types of family members to approach and how to approach them. Prior qualitative and quantitative pilot work we have conducted suggests that some of the largest barriers arise from decisions candidates make about which family members to ask for kidney transplants, and whether family members volunteer to be evaluated upon hearing of a candidate's diagnosis. We propose a multi-center study to collect novel data on transplant candidates' social networks and to test promising social network interventions that could reduce barriers to LDD KT, which we will evaluate with longitudinal medical records follow up. In the first year and a half of the project, we will build on prior qualitative, quantitative, and experimental pilot data we have collected to develop and refine two separate interventions in focus groups and survey vignette experiments. In years two through four, we will survey transplant candidates at two large transplant centers about their family and social networks, with special attention to candidate perceptions of their network members' health and willingness and ability to donate. During this time, we will also survey candidate network members using effective referral based survey strategies in order to obtain additional information on the barriers to donation among family and close social network members of kidney transplant candidates. We will assign each surveyed candidate to one of three experimental arms that encompass the interventions developed during the first year and a half of the project: a control group, a group that we coach on which of their network members to approach, and a group that we coach on how to approach their network members. In years four and five of the project, we will follow up on the candidates, examining whether they had a potential donor evaluated, who that donor was, and whether they were able to obtain a living donor transplant. The results of this project will contribute to basic and applied knowledge about social barriers to access in LDD KT, and quantify the efficacy of promising social network approaches for promoting greater utilization of LDD KT and reducing racial disparities therein.
