Individual-level social determinants of health and disparities in access to kidney transplant and waitlist mortality.

BACKGROUND: Comprehensive, individual-level social determinants of health (SDOH) are not collected in national transplant registries, limiting research aimed at understanding the relationship between SDOH and waitlist outcomes among kidney transplant candidates. METHODS: We merged Organ Procurement and Transplantation Network data with individual-level SDOH data from LexisNexis, a commercial data vendor, and conducted a competing risk analysis to determine the association between individual-level SDOH and the cumulative incidence of living donor kidney transplant (LDKT), deceased donor kidney transplant (DDKT), and waitlist mortality. We included adult kidney transplant candidates placed on the waiting list in 2020, followed through December 2023. RESULTS: In multivariable analysis, having public insurance (Medicare or Medicaid), less than a college degree, and any type of derogatory record (liens, history of eviction, bankruptcy and/ felonies) were associated with lower likelihood of LDKT. Compared with patients with estimated individual annual incomes ≤ $30,000, patients with incomes ≥ $120,000 were more likely to receive a LDKT (sub distribution hazard ratio (sHR), 2.52; 95% confidence interval (CI), 2.03-3.12). Being on Medicare (sHR, 1.49; 95% CI, 1.42-1.57), having some college or technical school, or at most a high school diploma were associated with a higher likelihood of DDKT. Compared with patients with incomes ≤ $30,000, patients with incomes ≥ $120,000 were less likely to receive a DDKT (sHR, 0.60; 95% CI, 0.51-0.71). Lower individual annual income, having public insurance, at most a high school diploma, and a record of liens or eviction were associated with higher waitlist mortality. CONCLUSIONS: Patients with adverse individual-level SDOH were less likely to receive LDKT, more likely to receive DDKT, and had higher risk of waitlist mortality. Differential relationships between SDOH, access to LDKT, DDKT, and waitlist mortality suggest the need for targeted interventions aimed at decreasing waitlist mortality and increasing access to LDKT among patients with adverse SDOH.

Crossing national borders for transplantation: A focused evaluation of deceased donor lung exports from the United States.

Organ transplantation is a life-saving treatment for end-stage organ failure patients, but the US faces a shortage of available organs. US policies incentivize identifying recipients for all recovered organs. Technological advancements have extended donor organ viability, creating new opportunities for long-distance transport and international sharing. We aimed to assess organ exports from deceased US donors to candidates abroad, a component of allocation policy allowed without suitable domestic candidates. Based on national SRTR data from January 2014-September 2023, 388,342 organs were recovered for transplantation, with 511(0.13%) exported. Most exported organs were lungs(80%). Exported lung donors were older(41 vs. 34 years,p<0.001), more likely Hepatitis-C positive(22% vs. 4%,p<0.001), and more likely donors after circulatory death(20% vs 7%,p<0.001). Lungs that were eventually exported were offered to more US PTRs (median=65) than those kept in the US(median=21 and 41 for lungs recovered by non-exporting and exporting OPOs;p<0.001). Our study highlights the necessity for further research and clear policy initiatives to balance the benefits of cross-border sharing while considering potential opportunities for more aggressive organ allocation within the US.

Disparities in Access to Timely Waitlisting Among Pediatric Kidney Transplant Candidates.

BACKGROUND AND OBJECTIVES: Kidney transplantation with minimal or no dialysis exposure provides optimal outcomes for children with end-stage kidney disease. We sought to understand disparities in timely access to transplant waitlisting. METHODS: We conducted a retrospective, registry-based cohort study of candidates ages 3 to 17 added to the US kidney transplant waitlist 2015 to 2019. We defined "preemptive waitlisting" as waitlist addition before receiving dialysis and compared demographics of candidates based on preemptive status. We used competing risk regression to determine the association between preemptive waitlisting and transplantation. We then identified waitlist additions age >18 who initiated dialysis as children, thereby missing pediatric allocation prioritization, and evaluated the association between waitlisting with pediatric prioritization and transplantation. RESULTS: Among 4506 pediatric candidates, 48% were waitlisted preemptively. Female sex, Hispanic ethnicity, Black race, and public insurance were associated with lower adjusted relative risk of preemptive waitlisting. Preemptive listing was not associated with time from waitlist activation to transplantation (adjusted hazard ratio 0.94, 95% confidence interval 0.87-1.02). Among transplant recipients waitlisted preemptively, 68% had no pretransplant dialysis, whereas recipients listed nonpreemptively had median 1.6 years of dialysis at transplant. Among 415 candidates initiating dialysis as children but waitlisted as adults, transplant rate was lower versus nonpreemptive pediatric candidates after waitlist activation (adjusted hazard ratio 0.54, 95% confidence interval 0.44-0.66). CONCLUSIONS: Disparities in timely waitlisting are associated with differences in pretransplant dialysis exposure despite no difference in time to transplant after waitlist activation. Young adults who experience delays may miss pediatric prioritization, highlighting an area for policy intervention.

Racial, Ethnic, and Regional Disparities of Post-Acute Service Utilization After Stroke in the United States.

Background and Objectives: Post-acute care is critical for patient functional recovery and successful community transition. This study aimed to understand the current racial, ethnic, and regional disparities in post-acute service utilization after stroke. Methods: This retrospective cross-sectional study included patients hospitalized for ischemic stroke and intracerebral hemorrhage in 2017-2018 using the National Inpatient Sample. Discharge destinations were classified as follows: (1) facility including inpatient rehabilitation, skilled nursing facility, and facility hospice; (2) home health care (HHC), including home health and home hospice; and (3) home without HHC. Multinomial logistic regression was used to study the odds of discharge to a facility over home and HHC over home without HHC by race, ethnicity, insurance, and census division, adjusting for clinical factors and survey design. Results: Among the 1,000,980 weighted ischemic stroke admissions, 66.9% were White, 17.6% Black, 9.5% Hispanic, 3.1% Asian American/Pacific Islander, and 0.4% Native American. Relative to private insurance, uninsured patients had the lowest adjusted odds of facility over home discharge (0.44; 95% CI 0.40-0.48) and HHC discharge over home without HHC (0.79; 95% CI 0.71-0.88). Compared with White patients, only Hispanic patients with Medicare/Medicaid insurance or self-pay had lower odds of facility over home discharge (adjusted OR 0.80 and 0.75, respectively; 95% CI 0.76-0.84 and 0.63-0.93). Uninsured Hispanic patients also had lower odds of HHC discharge over home without HHC than White patients (0.74; 95% CI 0.57-0.97). Facility discharge rate was the highest in East North Central (39.2%) and lowest in Pacific (31.2%). HHC discharge rate was the highest in New England (20.2%) and lowest in West North Central (10.3%), which had the highest home without HHC discharge (46.1%). Compared with New England, other census divisions had lower odds of facility over any home discharge with Pacific being the lowest (adjusted OR, 0.66; 95% CI 0.60-0.71) and HHC over home without HHC discharge with West North Central being the lowest (adjusted OR, 0.33; 95% CI 0.29-0.38). Similar patterns were observed in intracerebral hemorrhage. Discussion: Significant insurance-dependent racial and ethnic disparities and regional variations were evident in post-acute service utilization after stroke. Targeted efforts are needed to improve post-acute service access for uninsured patients especially Hispanic patients and people in certain regions.

Pragmatic strategies to address health disparities along the continuum of care in chronic liver disease.

Racial, ethnic, and socioeconomic disparities exist in the prevalence and natural history of chronic liver disease, access to care, and clinical outcomes. Solutions to improve health equity range widely, from digital health tools to policy changes. The current review outlines the disparities along the chronic liver disease health care continuum from screening and diagnosis to the management of cirrhosis and considerations of pre-liver and post-liver transplantation. Using a health equity research and implementation science framework, we offer pragmatic strategies to address barriers to implementing high-quality equitable care for patients with chronic liver disease.

Socioeconomic deprivation is associated with worse patient and graft survival following adult liver transplantation.

The impact of social determinants of health on adult liver transplant recipient outcomes is not clear at a national level. Further understanding of the impact of social determinants of health on patient outcomes can inform effective, equitable health care delivery. Unadjusted and multivariable models were used to analyze the Scientific Registry of Transplant Recipients to evaluate the association between the Social Deprivation Index (SDI) based on the liver transplant recipient's residential location and patient and graft survival. We included adult recipients between January 1, 2008 and December 1, 2021. Patient and graft survival were lower in adults living in areas with deprivation scores above the median. Five-year patient and graft survival were 78.7% and 76.5%, respectively, in the cohort above median SDI compared to 80.5% and 78.3% below median SDI. Compared to the recipients in low-deprivation residential areas, recipients residing in the highest deprivation (SDI quintile = 5) cohort had 6% higher adjusted risk of mortality (adjusted hazard ratio = 1.06, 95% CI: 1.01-1.13) and 6% higher risk of graft failure (adjusted hazard ratio = 1.06, 95% CI: 1.001-1.11). The increased risks for recipients residing in more vulnerable residential areas were higher (adjusted hazard ratio = 1.11, 95% CI: 1.03-1.20 for both death and graft loss) following the first year after transplantation. Importantly, the overall risk for graft loss associated with SDI was not linear but instead accelerated above the median level of deprivation. In the United States, social determinants of health, as reflected by residential distress, significantly impacts 5-year patient and graft survival. The overall effect of residential deprivation modest, and importantly, results illustrate they are more strongly associated with longer-term follow-up and accelerate at higher deprivation levels. Further research is needed to evaluate effective interventions and policies to attenuate disparities in outcomes among recipients in highly disadvantaged areas.

Geospatial Modeling Methods in Epidemiological Kidney Research: An Overview and Practical Example.

Geospatial modeling methods in population-level kidney research have not been used to full potential because few studies have completed associative spatial analyses between risk factors and exposures and kidney conditions and outcomes. Spatial modeling has several advantages over traditional modeling, including improved estimation of statistical variation and more accurate and unbiased estimation of coefficient effect direction or magnitudes by accounting for spatial data structure. Because most population-level kidney research data are geographically referenced, there is a need for better understanding of geospatial modeling for evaluating associations of individual geolocation with processes of care and clinical outcomes. In this review, we describe common spatial models, provide details to execute these analyses, and perform a case-study to display how results differ when integrating geographic structure. In our case-study, we used U.S. nationwide 2019 chronic kidney disease (CKD) data from Centers for Disease Control and Prevention's Kidney Disease Surveillance System and 2006 to 2010 U.S. Environmental Protection Agency environmental quality index (EQI) data and fit a nonspatial count model along with global spatial models (spatially lagged model [SLM]/pseudo-spatial error model [PSEM]) and a local spatial model (geographically weighted quasi-Poisson regression [GWQPR]). We found the SLM, PSEM, and GWQPR improved model fit in comparison to the nonspatial regression, and the PSEM model decreased the positive relationship between EQI and CKD prevalence. The GWQPR also revealed spatial heterogeneity in the EQI-CKD relationship. To summarize, spatial modeling has promise as a clinical and public health translational tool, and our case-study example is an exhibition of how these analyses may be performed to improve the accuracy and utility of findings.

Incomplete reporting of clinically significant acute rejection episodes in the national kidney transplant registry.

Administrative claims data could provide a unique opportunity to identify acute rejection (AR) events using specific antirejection medications and to validate rejected data reported to the Organ Procurement and Transplantation Network. This retrospective cohort study examined differences in registry-reported events and those identified using claims data among adult kidney transplant recipients from 2012 to 2017 using Standard Analysis Files from the US Renal Data System. Rejection rates, survival estimates, and center-level differences were assessed using each approach. Among 45 880 first-time kidney transplant recipients, we identified 3841 AR events within 12 months of transplant reported by centers in the registry; claims data yielded 2945 events. Of all events occurring within 12 months of transplant, 48.5% were reported using registry only, 32.9% were identified using claims only, and 18.6% were identified using both approaches. A 3-year death-censored graft survival probability was 90.0%, 88.4%, and 81.2% (P < .001) for ARs identified using registry only, claims data only, and both approaches, respectively. The large discordance between registry-reported and claims-based events suggests incomplete and potentially inaccurate reporting of events in the Organ Procurement Transplant Network registry. These findings have important implications for analyses that use AR data and underscore the need for improved capture of clinically meaningful events.

Cold Ischemia Time and Delayed Graft Function in Kidney Transplantation: A Paired Kidney Analysis.

BACKGROUND: We aimed to understand the association between cold ischemia time (CIT) and delayed graft function (DGF) after kidney transplantation and the impact of organ pumping on that association. METHODS: Retrospective cohort study using US registry data. We identified kidney pairs from the same donor where both kidneys were transplanted but had a CIT difference >0 and ≤20 h. We determined the frequency of concordant (both kidneys with/without DGF) or discordant (only 1 kidney DGF) DGF outcomes. Among discordant pairs, we computed unadjusted and adjusted relative risk of DGF associated with longer-CIT status, when then repeated this analysis restricted to pairs where only the longer-CIT kidney was pumped. RESULTS: Among 25 831 kidney pairs included, 71% had concordant DGF outcomes, 16% had only the longer-CIT kidney with DGF, and 13% had only the shorter-CIT kidney with DGF. Among discordant pairs, longer-CIT status was associated with a higher risk of DGF in unadjusted and adjusted models. Among pairs where only the longer-CIT kidney was pumped, longer-CIT kidneys that were pumped had a lower risk of DGF than their contralateral shorter-CIT kidneys that were not pumped regardless of the size of the CIT difference. CONCLUSIONS: Most kidney pairs have concordant DGF outcomes regardless of CIT difference, but even small increases in CIT raise the risk of DGF. Organ pumping may mitigate and even overcome the adverse consequences of prolonged CIT on the risk of DGF, but prospective studies are needed to better understand this relationship.

Public Reporting of Heart Transplant Center Performance: Promoting Clarity or Causing Confusion?

BACKGROUND: Transplant center report cards are publicly available and used by regulators, insurance payers, and importantly patients and families. OBJECTIVES: In this study, the authors sought to evaluate the variability in reported public performance ratings of pediatric and adult heart transplant centers. METHODS: Program-specific reports from the Scientific Registry of Transplant Recipients from 2017-2021 were used to evaluate stability, volatility, and reliability of 3 publicly reported ratings: waitlist survival (WS), getting to a faster transplant (FT), and post-transplantation graft failure (GF). RESULTS: There were 112 adult and 55 pediatric centers. Over the study period, nearly all centers (98%) had at least 1 change in rating in at least 1 of the tiers. The average time to the first rating change of any magnitude was 12-18 months for all tiers and centers. For adult centers, the most volatile rating was WS (SD: 0.77), followed by GF (SD: 0.76) and then FT (SD: 0.57). For pediatric centers, the most volatile rating was WS (SD: 0.79), followed by both GF (SD: 0.66) and FT (SD: 0.68), which were equally volatile. All tiers except adult FT had an estimated Fleiss's kappa <0.20, indicating poor agreement/consistency across the study period. In addition, the intraclass correlation coefficient for all tiers was <0.50, indicating poor reliability. CONCLUSIONS: The current 5-tier reporting of transplant center performance is highly volatile and has poor reliability and consistency. Given the unintended and significant negative consequences these reports can have, critical revision of these ratings is warranted.

Enhancing Kidney Transplantation and the Role of Xenografts: Report of a Scientific Workshop Sponsored by the National Kidney Foundation.

Chronic kidney disease affects an estimated 37 million people in the United States; of these,>800,000 have end-stage renal disease requiring chronic dialysis or a kidney transplant to survive. Despite efforts to increase the donor kidney supply, approximately 100,000 people are registered on the kidney transplant wait-list with no measurable decrease over the past 2 decades. The outcomes of kidney transplantation are significantly better than for chronic dialysis: kidney transplant recipients have lower rates of mortality and cardiovascular events and better quality of life, but wait-list time matters. Time on dialysis waiting for a deceased-donor kidney is a strong independent risk factor for outcomes after a kidney transplant. Deceased-donor recipients with wait-list times on dialysis of<6 months have graft survival rates equivalent to living-donor recipients with waitlist times on dialysis of>2 years. In 2021,>12,000 people had been on the kidney transplant waitlist for ≥5 years. As the gap between the demand for and availability of donor kidneys for allotransplantation continues to widen, alternative strategies are needed to provide a stable, sufficient, and timely supply. A strategy that is gaining momentum toward clinical application is pig-to-human kidney xenotransplantation. This report summarizes the proceedings of a meeting convened on April 11-12, 2022, by the National Kidney Foundation to review and assess the state of pig-to-human kidney xenotransplantation as a potential cure for end-stage renal disease.

Association of procurement technique with organ yield and cost following donation after circulatory death.

Donation after circulatory death (DCD) could account for the largest expansion of the donor allograft pool in the contemporary era. However, the organ yield and associated costs of normothermic regional perfusion (NRP) compared to super-rapid recovery (SRR) with ex-situ normothermic machine perfusion, remain unreported. The Organ Procurement and Transplantation Network (December 2019 to June 2023) was analyzed to determine the number of organs recovered per donor. A cost analysis was performed based on our institution's experience since 2022. Of 43 502 donors, 30 646 (70%) were donors after brain death (DBD), 12 536 (29%) DCD-SRR and 320 (0.7%) DCD-NRP. The mean number of organs recovered was 3.70 for DBD, 3.71 for DCD-NRP (P < .001), and 2.45 for DCD-SRR (P < .001). Following risk adjustment, DCD-NRP (adjusted odds ratio 1.34, confidence interval 1.04-1.75) and DCD-SRR (adjusted odds ratio 2.11, confidence interval 2.01-2.21; reference: DBD) remained associated with greater odds of allograft nonuse. Including incomplete and completed procurement runs, the total average cost of DCD-NRP was $9463.22 per donor. By conservative estimates, we found that approximately 31 donor allografts could be procured using DCD-NRP for the cost equivalent of 1 allograft procured via DCD-SRR with ex-situ normothermic machine perfusion. In conclusion, DCD-SRR procurements were associated with the lowest organ yield compared to other procurement methods. To facilitate broader adoption of DCD procurement, a comprehensive understanding of the trade-offs inherent in each technique is imperative.