Faculty Bibliography

BACKGROUND:Recent data suggest patients with graft failure had better access to repeat kidney transplantation (re-KT) than transplant-naive dialysis accessing first KT. This was postulated to be because of better familiarity with the transplant process and healthcare system; whether this advantage is equitably distributed is not known. We compared the magnitude of racial/ethnic disparities in access to re-KT versus first KT. METHODS:Using United States Renal Data System, we identified 104 454 White, Black, and Hispanic patients with a history of graft failure from 1995 to 2018, and 2 357 753 transplant-naive dialysis patients. We used adjusted Cox regression to estimate disparities in access to first and re-KT and whether the magnitude of these disparities differed between first and re-KT using a Wald test. RESULTS:Black patients had inferior access to both waitlisting and receiving first KT and re-KT. However, the racial/ethnic disparities in waitlisting for (adjusted hazard ratio [aHR] = 0.77; 95% confidence interval [CI], 0.74-0.80) and receiving re-KT (aHR = 0.61; 95% CI, 0.58-0.64) was greater than the racial/ethnic disparities in first KT (waitlisting: aHR = 0.91; 95% CI, 0.90-0.93; Pinteraction = 0.001; KT: aHR = 0.68; 95% CI, 0.64-0.72; Pinteraction < 0.001). For Hispanic patients, ethnic disparities in waitlisting for re-KT (aHR = 0.83; 95% CI, 0.79-0.88) were greater than for first KT (aHR = 1.14; 95% CI, 1.11-1.16; Pinteraction < 0.001). However, the disparity in receiving re-KT (aHR = 0.76; 95% CI, 0.72-0.80) was similar to that for first KT (aHR = 0.73; 95% CI, 0.68-0.79; Pinteraction = 0.55). Inferences were similar when restricting the cohorts to the Kidney Allocation System era. CONCLUSIONS:Unlike White patients, Black and Hispanic patients with graft failure do not experience improved access to re-KT. This suggests that structural and systemic barriers likely persist for racialized patients accessing re-KT, and systemic changes are needed to achieve transplant equity.

INTRODUCTION/BACKGROUND:ChatGPT has shown the ability to answer clinical questions in general medicine but may be constrained by the specialized nature of kidney transplantation. Thus, it is important to explore how ChatGPT can be used in kidney transplantation and how its knowledge compares to human respondents. METHODS:We prompted ChatGPT versions 3.5, 4, and 4 Visual (4 V) with 12 multiple-choice questions related to six kidney transplant cases from 2013 to 2015 American Society of Nephrology (ASN) fellowship program quizzes. We compared the performance of ChatGPT with US nephrology fellowship program directors, nephrology fellows, and the audience of the ASN's annual Kidney Week meeting. RESULTS:Overall, ChatGPT 4 V correctly answered 10 out of 12 questions, showing a performance level comparable to nephrology fellows (group majority correctly answered 9 of 12 questions) and training program directors (11 of 12). This surpassed ChatGPT 4 (7 of 12 correct) and 3.5 (5 of 12). All three ChatGPT versions failed to correctly answer questions where the consensus among human respondents was low. CONCLUSION/CONCLUSIONS:Each iterative version of ChatGPT performed better than the prior version, with version 4 V achieving performance on par with nephrology fellows and training program directors. While it shows promise in understanding and answering kidney transplantation questions, ChatGPT should be seen as a complementary tool to human expertise rather than a replacement.

INTRODUCTION/BACKGROUND:Dietary restrictions for patients with end-stage kidney disease (ESKD) are burdensome. Kidney transplantation (KT) candidates who lack neighborhood resources and are burdened by dietary restrictions may have decreased access to KT. METHODS:In our two-center prospective cohort study (2014-2023), 2471 ESKD patients who were evaluated for KT (candidates) reported their perceived burden of dietary restrictions (not at all, somewhat/moderately, or extremely bothered). Neighborhood-level socioeconomic factors were derived from residential ZIP codes. We quantified the association of perceived burden of the dietary restrictions with a chance of listing using Cox models and risk of waitlist mortality using competing risks models. Then we tested whether these associations differed by neighborhood-level socioeconomic factors. RESULTS: = 0.02). The association between dietary burden and waitlist mortality did not differ by neighborhood-level healthy food access. CONCLUSION/CONCLUSIONS:The perceived burden of dietary restrictions is associated with a lower chance of listing for KT, and higher waitlist mortality only among candidates residing in neighborhoods with high food insecurity. Transplant centers should identify vulnerable patients and support them with nutrition education and access to food assistance programs.

BACKGROUND/UNASSIGNED:Fewer minoritized patients with end-stage kidney disease (ESKD) receive kidney transplantation (KT); efforts to mitigate disparities have thus far failed. Pinpointing the specific stage(s) within the transplant care continuum (being informed of KT options, joining the waiting list, to receiving KT) where disparities emerge among each minoritized population is pivotal for achieving equity. We therefore quantified racial and ethnic disparities across the KT care continuum. METHODS/UNASSIGNED:We conducted a retrospective cohort study (2015-2020), with follow-up through 12/10/2021. Patients with incident dialysis were identified using the US national registry data. The exposure was race and ethnicity (Asian, Black, Hispanic, and White). We used adjusted modified Poisson regression to quantify the adjusted prevalence ratio (aPR) of being informed of KT, and cause-specific hazards models to calculate adjusted hazard ratios (aHR) of listing, and transplantation after listing. FINDINGS/UNASSIGNED:Among 637,951 adults initiating dialysis, the mean age (SD) was 63.8 (14.6), 41.8% were female, 5.4% were Asian, 26.3% were Black, 16.6% were Hispanic, and 51.7% were White (median follow-up in years [IQR]:1.92 [0.97-3.39]). Black and Hispanic patients were modestly more likely to be informed of KT (Black: aPR = 1.02, 95% confidence interval [CI]:1.01-1.02; Hispanic: aPR = 1.03, 95% CI: 1.02-1.03) relative to White patients. Asian patients were more likely to be listed (aHR = 1.18, 95% CI: 1.15-1.21) but less likely to receive KT (aHR = 0.56, 95% CI: 0.54-0.58). Both Black and Hispanic patients were less likely to be listed (Black: aHR = 0.87, 95% CI: 0.85-0.88; Hispanic: aHR = 0.85, 95% CI: 0.85-0.88) and receive KT (Black: aHR = 0.61, 95% CI: 0.60-0.63; Hispanic: aHR = 0.64, 95% CI: 0.63-0.66). INTERPRETATION/UNASSIGNED:Improved characterization of the barriers in KT access specific to each racial and ethnic group, and the interventions to address these distinct challenges throughout the KT care continuum are needed; our findings identify specific stages most in need of mitigation. FUNDING/UNASSIGNED:National Institutes of Health.

INTRODUCTION/BACKGROUND:Frailty and cognitive function are often measured during kidney transplant evaluation. However, patient perspectives on the ethical considerations of this practice are unclear. RESEARCH QUESTION/OBJECTIVE:What are patient perspectives on the use of aging metrics in kidney transplant decision-making? DESIGN/METHODS:One hundred participants who were evaluated for kidney transplantation and were enrolled in an ongoing prospective cohort study (response rate = 61.3%) were surveyed. Participants were informed of the definitions of frailty and cognitive impairment and then asked survey questions regarding the use of these measures of aging to determine kidney transplant candidacy. RESULTS:Participants (75.6%) thought it was unfair to prevent older adults from receiving a kidney transplant based on age, but there was less agreement on whether it was fair to deny frail (46.5%) and cognitively impaired (45.9%) patients from accessing kidney transplantation. Compared to older participants, younger participants had 5.36-times (95%CI:1.94-14.81) the odds of choosing a hypothetical younger, frail patient to list for kidney transplantation than an older, non-frail patient; they also had 3.56-times (95%CI:1.33-9.56) the odds of choosing the hypothetical frail patient with social support rather than a non-frail patient without social support. Participants disagreed on the use of patient age as a listing criterion; 19.5% ranked it as the fairest and 28.7% as the least fair. CONCLUSION/CONCLUSIONS:The patient views highlighted in this study are an important step toward developing ethical guidelines to ensure fair use of frailty, cognitive function, and chronological age for kidney transplant decision-making.

OBJECTIVES/OBJECTIVE:Obesogenic medications are a putative contributor to the obesity epidemic. While 20% of adults take ≥1 obesogenic medication, the proportion in the end-stage kidney disease (ESKD) population-a group enriched for cardiometabolic complications-is unknown. Obesogenic medications may contribute to obesity and hamper weight loss efforts to achieve transplant listing. METHODS:Using 2017-2020 USRDS and Medicare claims, patients were identified as taking obesogenic medications if prescribed anticonvulsants, antidepressants, antidiabetics, anti-inflammatories, antipsychotics, and/or antihypertensives known to cause weight gain for ≥30 days in their first hemodialysis year. Ordinal logistic and Cox regression with inverse probability of treatment weighting were used to quantify obesogenic medications' association with body mass index (BMI) and listing, respectively. RESULTS:Among 271 401 hemodialysis initiates, 63.5% took ≥1 obesogenic medication. For those in underweight, normal weight, overweight, and class I, II, and III categories, 54.3%, 58.4%, 63.1%, 66.5%, 68.6%, and 68.8% took ≥1, respectively. Number of obesogenic medications was associated with increased BMI; use of one was associated with 13% increased odds of higher BMI (aOR [adjusted odds ratio] 1.14; 95%CI: 1.13-1.16; p < 0.001), use of three was associated with a 55% increase (aOR 1.55; 95%CI: 1.53-1.57; p < 0.001). Any use was associated with 6% lower odds of transplant listing (aHR [adjusted hazard ratio] 0.94; 95%CI: 0.92-0.96; p < 0.001). Within each BMI category, obesogenic medication use was associated with lower listing likelihood. CONCLUSIONS:Obesogenic medication use is common in ESKD patients-particularly those with obesity-and is associated with lower listing likelihood. Whenever possible, non-obesogenic alternatives should be chosen for ESKD patients attempting weight loss to achieve transplant listing.

KEY POINTS:Regardless of race and ethnicity, older adults with kidney failure residing in or receiving care at dialysis facilities located in high-segregation neighborhoods were at a 1.63-fold and 1.53-fold higher risk of dementia diagnosis, respectively. Older adults with kidney failure residing in minority-predominant high-segregation neighborhoods had a 2.19-fold higher risk of dementia diagnosis compared with White individuals in White-predominant neighborhoods. BACKGROUND:a form of structural racism recently identified as a mechanism in numerous other health disparities. METHODS:We identified 901,065 older adults (aged ≥55 years) with kidney failure from 2003 to 2019 using the United States Renal Data System. We quantified dementia risk across tertiles of residential neighborhood segregation score using cause-specific hazard models, adjusting for individual- and neighborhood-level factors. We included an interaction term to quantify the differential effect of segregation on dementia diagnosis by race and ethnicity. RESULTS: CONCLUSIONS:Residing in or receiving care at dialysis facilities located in high-segregation neighborhoods was associated with a higher risk of dementia diagnosis among older individuals with kidney failure, particularly minoritized individuals.

BACKGROUND:Medical distrust may hinder kidney transplantation (KT) access. Among KT candidates evaluated for waitlisting, we identified factors associated with high distrust levels and quantified their association with waitlisting. METHODS:Among 812 candidates (2018-2023), we assessed distrust using the Revised Health Care System Distrust Scale across composite, competence, and values subscales. We used linear regression to quantify the associations between candidate and neighborhood-level factors and distrust scores. We used Cox models to quantify the associations between distrust scores and waitlisting. RESULTS:At KT evaluation, candidates who were aged 35-49 years (difference = 1.97, 95% CI: 0.78-3.16), female (difference = 1.10, 95% CI: 0.23-1.97), and Black (difference = 1.47, 95% CI: 0.47-2.47) were more likely to report higher composite distrust score. For subscales, candidates aged 35-49 were more likely to have higher competence distrust score (difference = 1.14, 95% CI: 0.59-1.68) and values distrust score (difference = 0.83, 95% CI: 0.05-1.61). Race/ethnicity (Black, difference = 1.42, 95% CI: 0.76-2.07; Hispanic, difference = 1.52, 95% CI: 0.35-2.69) was only associated with higher values distrust scores. Female candidates reporting higher rescaled values distrust scores (each one point) had a lower chance of waitlisting (aHR = 0.78, 95% CI: 0.63-0.98), whereas this association was not observed among males. Similarly, among non-White candidates, each 1-point increase in both rescaled composite (aHR = 0.87, 95% CI: 0.77-0.99) and values (aHR = 0.82, 95% CI: 0.68-0.99) distrust scores was associated with a lower chance of waitlisting, while there was no association among White candidates. CONCLUSION/CONCLUSIONS:Female, younger, and non-White candidates reported higher distrust scores. Values distrust may contribute to the long-standing racial/ethnic and gender disparities in access to KT. Implementing tailored strategies to reduce distrust in transplant care may improve KT access for groups that experience persistent disparities.