Faculty Bibliography

RATIONALE & OBJECTIVE/OBJECTIVE:Despite national efforts, the uptake of home dialysis (peritoneal dialysis or home hemodialysis) remains low. Characteristics of the built environment may differentially impact home dialysis use. STUDY DESIGN/METHODS:Retrospective cohort study (2010-2019). SETTING & PARTICIPANTS/METHODS:1,103,695 adults (aged≥18 years) initiating dialysis in the US Renal Data System. EXPOSURE/METHODS:We examined 3 built environment domains based on residential ZIP code: (1) medically underserved areas (MUAs), defined as neighborhoods with limited primary care access; (2) distance to the nearest dialysis facility; and (3) distribution of housing characteristics (structure and overcrowding). OUTCOME/RESULTS:Uptake of home dialysis modalities at dialysis initiation. ANALYTICAL APPROACH/METHODS:We quantified associations between built environment characteristics and home dialysis initiation using multilevel logistic regression stratified by urbanicity type (urban, suburban, small-town, and rural). RESULTS:Among adults initiating dialysis, 40.8% lived in MUAs. Across ZIP codes, the mean percentage of overcrowded housing was 4.2% (SD, 4.7%), and the percentage of detached housing was 61.1% (SD, 21.1%); mean distance to the nearest dialysis facility was 5.5km (SD, 9.1km). Living in MUAs was associated with reduced home dialysis use only in urban (OR, 0.94; 95% CI, 0.91-0.96) and suburban (OR, 0.92; 95% CI, 0.89-0.94) areas. Similarly, housing overcrowding was associated with decreased home dialysis use only in urban (OR, 0.88; 95% CI, 0.86-0.89) and suburban (OR, 0.91; 95% CI, 0.90-0.93) areas. Longer distance to a dialysis facility was the most salient neighborhood factor associated with increased home dialysis use in small towns (OR, 1.14; 95% CI, 1.12-1.16) and rural areas (OR, 1.17; 95% CI, 1.15-1.19). LIMITATIONS/CONCLUSIONS:Housing characteristics were measured at the ZIP code level. CONCLUSIONS:Built environment characteristics associated with home dialysis uptake vary by urbanicity. Policies should address built environment barriers that are specific to urbanicity level. For example, increasing the frequency of dialysate delivery schedules could address housing space constraints in urban and suburban areas, and promoting home dialysis might be more effective for patients living far from dialysis centers in small-town and rural areas.

Unauthorized immigrants and permanent residents may experience challenges in accessing kidney transplantation due to limited healthcare access, socioeconomic and cultural barriers. Understanding the United States (US) national landscape of kidney transplantation for non-citizens may inform policy changes. To evaluate this, we utilized two cohorts from the US national registry (2013-2023): 287,481 adult candidates for first transplant listing and 190,176 adult first transplant recipients. Citizenship was categorized as US citizen (reference), permanent resident, and presumed unauthorized immigrant. Negative binomial regression was used to quantify the incidence rate ratio over time by citizenship status. Cause-specific hazards models, with clustering at the state of listing/transplant, were used to calculate the adjusted hazard ratio of waitlist mortality, kidney transplant, and post-transplant outcomes (mortality/death-censored graft failure) by citizenship category. The crude proportion of presumed unauthorized immigrants listed increased over time (2013: 0.9%, 2023:1.9%). However, after accounting for case mix and waitlist size, there was no change in listing over time. Presumed unauthorized immigrants were less likely to experience waitlist mortality (adjusted Hazard Ratio 0.54, 95% Confidence Interval: 0.46-0.62), were more likely to obtain deceased donor kidney transplant (1.11: 1.05-1.18), but less likely to receive live donor (0.80: 0.71-0.90) or preemptive kidney transplant (0.52: 0.43- 0.62). When stratified by insurance status, presumed unauthorized immigrants on Medicaid were less likely to receive deceased donor kidney transplants compared to their citizen counterparts; however, presumed unauthorized immigrants with Private insurance or Medicare were more likely to receive deceased donor kidney transplants. Presumed unauthorized immigrants were less likely to experience post-transplant death (0.56: 0.43-0.69) and graft failure (0.69: 0.57-0.84). Residents had similar pre- and post-transplant outcomes. Despite the barriers to kidney transplantation faced by presumed unauthorized immigrants and residents in the US, better post-transplant outcomes for presumed unauthorized immigrants compared to citizens persisted, even after accounting for differences in patient characteristics.

Transplantation of kidneys from donors with HIV to recipients with HIV (HIV D+/R+) has been shown to be safe and effective, but there is a unique risk of donor-derived HIV-superinfection (HIV-SI) in these recipients. Recipients from a multicenter observational HIV D+/R+ study were examined for HIV-SI using site-directed next-generation sequencing (Illumina). Eighteen HIV D+/R+ kidney transplant recipients had both baseline and follow-up samples that successfully amplified. One recipient was confirmed to have experienced donor-derived HIV-SI at week 26, but did not experience any clinically significant changes. HIV-SI in HIV D+/R+ transplant recipients is rare, and the clinical ramifications appear negligible.

The benefits of bilateral lung transplantation (BLT) versus single lung transplantation (SLT) are still debated. One impediment to clinical recommendations is that BLT vs. SLT advantages may vary based on underlying disease. Since both options are clinically tenable in patients with emphysema, we conducted a comprehensive assessment of lung allograft survival in this population. Using U.S. registry data, we studied time to all-cause allograft failure in 8,092 patients 12 years or older transplanted from 2006 to 2022, adjusting for recipient, donor, and transplant factors by inverse propensity weighting. Median allograft survival was 6.6 years in BLT compared to 5.3 years in SLT, a 25% risk-adjusted survival advantage of _0.81.3_1.8 years. Risk-adjusted bilateral survival advantages varied between 0.9 and 2.4 years across eleven subgroups. Median allograft survival in BLT was 1.2 years greater than right SLT and 2.0 years greater than left SLT. During the 16-year study period, allograft survival steadily improved for BLT but not for SLT. Although the 25% BLT survival advantage pre-dated the pandemic, COVID-19 may have contributed to an apparent SLT survival decline. Recognizing the possible influence of residual confounding due to selection biases, these findings may aid offer decision-making when both donor lungs are available.

BACKGROUND:Due to high prevalence of Kaposi Sarcoma (KS)-Associated Herpesvirus (KSHV) among people with HIV, KSHV-associated disease (KAD) may be increased after kidney transplantation from donors with HIV (HIV D+) to recipients with HIV (HIV R+). METHODS:Anti-KSHV antibodies were measured in HIV R+ and donors with and without HIV (HIV D-) using a 30-antigen multiplex assay within three multicenter kidney transplantation studies. KSHV seropositivity was defined as reactivity to conventional KSHV antigens (≥1 ORF73 or K8.1); reactivity to expanded 5-antigen and 30-antigen panels were also reported. Risk factors were identified using modified Poisson regression. Recipients were monitored for post-transplant anti-KSHV antibody changes and KAD. RESULTS:KSHV seroprevalence was 40.6% (143/352) among HIV R+, 25.2% (33/131) among HIV D+, and 7.5% (4/53) among HIV D-. In the multivariable model, only men who have sex with men (MSM) was associated with KSHV seropositivity: relative risk 1.51 (95% confidence interval [CI] 1.07-2.14) in recipients and 2.39 (95%CI 1.03-5.53) in donors. Among 418 HIV R+ (215 HIV D+/R+, 203 HIV D-/R+), there were 5 KAD cases (incidence 0.63 cases/100 person-years, 95%CI 0.26-1.52): 3 skin-only KS, 1 multicentric Castleman disease, 1 allograft KS. The allograft KS occurred in a female HIV D+/R+ and was likely donor-derived. Remaining KAD cases occurred in male HIV D-/R+ and were likely recipient KSHV reactivation or acquisition. CONCLUSIONS:In the United States, KSHV seroprevalence in donors and recipients with HIV was high, particularly among MSM. Reassuringly, KSHV-associated disease was rare, and primarily attributed to recipient rather than donor-derived KSHV.

BACKGROUND:Given the cardiovascular, renal, and survival benefits of GLP-1 receptor agonists for diabetes, these agents could be effective among kidney transplant recipients. However, kidney transplant recipients are distinct from GLP-1 receptor agonist trial participants, with longer diabetes duration and severity, greater end-organ damage, increased cardiovascular risk, and multimorbidity. We examined GLP-1 receptor agonist real-world effectiveness and safety in kidney transplant recipients with diabetes. METHODS:This USA-based retrospective cohort study included kidney transplant recipients with type 2 diabetes at transplantation and Medicare as their primary insurance from a national registry linked with Medicare claims. Post-transplantation GLP-1 receptor agonist use was identified through Medicare claims. Death-censored graft loss was estimated using the Fine-Gray sub-distribution hazard model and extended Cox models were used for mortality and safety endpoints. Models incorporated inverse probability of treatment weights. To further test whether bias could affect the main results, a cohort was created in which each GLP-1 receptor agonist user was matched with a kidney transplant recipient who had not started a GLP-1 receptor agonist, was alive with a functioning graft, and had accrued the same amount of post-transplant survival time. FINDINGS/RESULTS:Between Jan 1, 2013 and Dec 31, 2020, we identified 44 536 first time kidney transplant recipients with Medicare as primary payer in the 6 months before and at transplantation. 24 192 patients were excluded as they did not have type 2 diabetes. 2328 patients were ineligible (1916 had missing values and 412 used GLP-1 receptor agonists before transplantation). The primary cohort thus consisted of 18 016 kidney transplant recipients with diabetes. Of these patients, 1969 (10·9%) had at least one GLP-1 receptor agonist prescription filled post-transplant. Compared with patients who had not received a GLP-1 receptor agonist, GLP-1 receptor agonist users were younger (median age at transplant 57 years [IQR 49-64] vs 60 years [51-66], p<0·0001) and more likely to be female (786 [39·9%] vs 5645 [35·2%], p<0·0001). Among GLP-1 receptor agonist users, 552 [28·0%] were non-Hispanic White, 703 [35·7%] were non-Hispanic Black, and 568 [28·8%] were Hispanic. The 5-year unadjusted cumulative incidence of death-censored graft loss from a cohort matched on survival time before GLP-1 receptor agonist initiation was 6·0% for GLP-1 receptor agonist users and 10·7% for non-users (Gray's test p=0·004). The 5-year unadjusted cumulative incidence for mortality from a cohort matched on survival time before GLP-1 receptor agonist initiation was 17·0% for GLP-1 receptor agonist users and 25·8% for non-users (log-rank p=0·0006). The 5-year unadjusted cumulative incidence for mortality was 13·5% for GLP-1 receptor agonist users and 19·9% for non-users (log-rank p<0·0001). GLP-1 receptor agonist use was associated with a 49% lower incidence of death-censored graft loss (adjusted subhazard ratio [aSHR] 0·51, 95% CI 0·36-0·71; p=0·0001) and 31% lower mortality (adjusted hazard ratio [aHR] 0·69, 95% CI 0·55-0·86; p=0·001). Inferences were robust when matched on survival time (death-censored graft loss aSHR 0·53, 95% CI 0·37-0·75; p=0·0005; mortality aHR 0·70, 95% CI 0·55-0·88; p=0·003). Safety endpoints were rare and not associated with GLP-1 receptor agonists, with the exception of diabetic retinopathy (aHR 1·49, 1·11-2·00; p=0·008). INTERPRETATION/CONCLUSIONS:GLP-1 receptor agonists were associated with better graft and patient survival. Clinical trials are needed to confirm these findings. FUNDING/BACKGROUND:National Institutes of Health.

INTRODUCTION/BACKGROUND:Dialysis social workers (DSWs) educate and advocate for end-stage kidney disease (ESKD) patients during the kidney transplantation (KT) process. However, little is known about the barriers DSWs face as they help patients get waitlisted and how to best support their efforts. We interviewed DSWs across New York (NY) State to examine their experiences, supports, and challenges in helping dialysis patients progress through KT education, referral, and evaluation. METHODS:We conducted semi-structured interviews with DSWs in NY State who had participated or expressed interest in a program designed to educate DSWs about KT and used rapid qualitative analysis to identify themes. FINDINGS/RESULTS:We interviewed 17 DSWs. Seven themes emerged: (1) DSWs report involvement in KT interest assessment, education, referral, and evaluation support, (2) DSWs report varying nephrologist support in helping patients progress to KT, (3) DSWs perceive social support and adherence as key factors in KT centers' eligibility determinations, (4) DSWs have knowledge gaps around living donation and appreciate learning about KT from transplant centers and non-profit organizations, (5) Patients express KT concerns and DSWs counsel them about these concerns, (6) DSWs report solutions to help patients complete KT evaluation appointments, and (7) DSWs report communication deficiencies between dialysis centers and transplant centers, and patients. CONCLUSIONS:Education for DSWs, support from nephrologists, and resources to help patients complete KT evaluation steps facilitated DSW engagement throughout the pre-transplant process, underscoring the need for multi-level, cross-disciplinary programs to support these efforts.

BACKGROUND:Renal dysfunction is common among liver transplant candidates and can resolve, persist, or develop de novo following liver transplantation (LT). In light of the 2017 policy changes to simultaneous liver-kidney transplant and the post-LT kidney transplant safety net eligibility, we evaluated risk factors for and change in the incidence of post-LT renal dysfunction. METHODS:Using SRTR data for adult deceased-donor liver-only transplant recipients 2010-2022, we evaluated secular trends in and risk factors for the development of post-LT ESRD at 1 year and overall using multivariable logistic and Cox regression. We compared observed versus expected incidence of ESRD at 1-year post-LT using weighting by odds. RESULTS:Among 77 565 LT recipients, 6032 (7.8%) developed ESRD during the study period, of whom 2354 (39.0%) developed ESRD within the first year after LT. In a multivariable model, diabetes (aOR 1.63, 95% CI 1.48-1.79, p < 0.001), pre-LT eGFR (aOR 0.97 per unit, 95% CI 0.97-0.97, p < 0.001), and MELD category remained independently associated with ESRD within 1-year post-LT. Odds of ESRD by 1 year post-LT were 47% higher than expected post-2017 after accounting for changes in donor and recipient characteristics. CONCLUSIONS:The rising 1-year post-LT ESRD risk highlights the need to reassess safety net eligibility beyond 1 year and prioritize counseling on risk minimization, including post-transplant diabetes management and potential adjustments to immunosuppression protocols to improve outcomes.

BACKGROUND:Parents of pediatric heart transplant (HTx) recipients have a unique perspective on the challenges associated with the transition into adult care networks. We sought to assess parental perceptions of the challenges pediatric HTx recipients face daily and parental concerns around the transition from pediatric care networks. METHODS:A 15-item online survey was developed in partnership with parent-stakeholders and administered to parents of pediatric HTx recipients in September 2023. Closed and open-ended questions assessed (1) the patients' diagnosis, age at diagnosis, and age at transplant, (2) parents' daily concerns about their child's well-being, (3) parents' overall concerns about their child's well-being as they transition into adulthood, (4) parents' perceptions of their child's quality-of-life (QoL) and health, and (5) parents' demographic characteristics. RESULTS:Eighty-six parents completed the survey. On a scale of 1 (worst) to 10 (best), 75% of parents rated their child's overall QoL at 8 or higher and 76% rated their child's health-related QoL at 8 or higher. Parents' daily concerns about their child's well-being included infectious diseases, health behaviors and care management, transplant-related concerns, socialization and education, mental health, and care coordination. Concerns related to the transition into adulthood included health behaviors and self-management, life satisfaction, finances, family, transplant-related concerns, and care coordination. CONCLUSIONS:Although parents of pediatric HTx recipients reported mostly positive QoL outcomes, they have concerns related to care management, life satisfaction, and healthcare access as their children transition into adulthood. Comprehensive transition-specific interventions and guidelines are needed to support families during this high-risk period.

INTRODUCTION/BACKGROUND:Obesity prevalence has dramatically increased; candidates with obesity have higher waitlist mortality and are less likely to undergo liver transplantation. The association of obesity with post-transplant mortality is inconsistent. MATERIALS AND METHODS/METHODS:. Risks of waitlist and post-transplant mortality were quantified using adjusted competing risks and Cox proportional hazards. RESULTS:Of 103,640 candidates and 58,692 recipients, candidates with higher obesity classes had higher listing MELD that increased over time. Candidates with class III obesity were listed and transplanted at higher MELD compared to candidates without obesity, class I and II obesity; nearly 40% of candidates with class III obesity had listing MELD≥30. From 2013-2017 to 2018-2023, waitlist mortality decreased 35% in candidates with class III obesity (SHR:0.65(0.58-0.73),p<0.001) and post-transplant mortality decreased 20% for recipients with class III obesity (HR:0.80(0.66-0.96),p=0.02). However, over time, post-transplant mortality differed by obesity class with no reduction in post-transplant mortality for recipients with class I or II obesity. CONCLUSION/CONCLUSIONS:Candidates and recipients with class III obesity are being listed and transplanted at higher MELD scores with improvement in outcomes over time. Although higher risk, temporal trends for LT in this population are favorable. Given the higher disease severity at listing for candidates with class III obesity, referral patterns for LT evaluation in these patients should be evaluated.