Faculty Bibliography

Liver transplant (LT) recipients experience a wide range of comorbidities, leading to frequent healthcare encounters. Until now, national registries, which have limited exposures and outcomes, and laborious small cohort studies have been the main data sources for LT research. Cosmos database offers electronic health record (EHR)-based insights into LT recipients at the national level with granular data. We evaluated if Cosmos data is representative of the entire US LT recipient population. Using Cosmos (N=20,235) and the national Scientific Registry of Transplant Recipients (SRTR) (N=51,281), we identified adult, first-time LT recipients between 7/2016-12/2022. We compared demographics, clinical data, and mortality across datasets, calculating Kaplan-Meier survival estimates and multi-variable Cox regressions. Recipient characteristics were highly comparable (e.g., female: Cosmos=36.5% vs. SRTR=36.4%, Black: 6.8% vs. 7.2%; BMI: 28.5 kg/m2 [24.8-32.9] vs. 28.2 [24.6-32.4]). Lab values were similar across cohorts, including MELD (24 [17-30] vs. 23 [16-30]). Transplant indications, donor characteristics, and 5-year survival (Cosmos 83.1% [82.3-83.8) vs. SRTR 80.9% [80.4-81.3]) were similar. The associations of clinical factors with survival were similar across both groups. Cosmos database demonstrated acceptable generalizability to the general US LT recipient population, which may advance LT research through a better understanding about LT recipients' experiences and outcomes.

INTRODUCTION/BACKGROUND:Following implementation of the U.S. Kidney Allocation System (KAS) in 2014, deceased donor kidneys with a kidney donor profile index (KDPI) < 35% are prioritized for allocation to pediatric candidates. Early post-KAS data suggested this prioritization may have led to more frequent delayed graft function compared to pre-KAS, when pediatric allocation priority was based on donor age < 35 years. We sought to understand the impact of this allocation change on longer-term pediatric kidney transplant outcomes. METHODS:We used SRTR data to identify all deceased donor kidney transplants with pediatric recipients during two eras: "Pre-KAS" (12/1/2009-11/30/2014) and "KAS" (12/1/2015-11/30/2020). We used Cox proportional hazards models to calculate the association between study era and all-cause graft failure (graft failure or death) after adjusting for recipient characteristics. RESULTS:, p = 0.001). Results were similar in sensitivity analyses limited to recipients < 10 years old and recipients alive with a functioning graft 90 days post-transplant. CONCLUSIONS:KDPI-based prioritization of kidneys for pediatric allocation was associated with a lower risk of graft failure compared to donor age-based prioritization. Further refining donor risk scores may enable additional improvements in graft survival.

RATIONALE & OBJECTIVE/UNASSIGNED:exposure and mortality, overall and by race and ethnicity. STUDY DESIGN/UNASSIGNED:Cohort study (2003-2019). SETTING & PARTICIPANTS/UNASSIGNED:National registry for patients with kidney failure. EXPOSURES/UNASSIGNED:), segregation scores (Theil's H method), deprivation scores (American Community Survey), and built environment factors (medically underserved areas [MUA] and urbanicity) by patients' residential ZIP code at dialysis initiation. OUTCOME/UNASSIGNED:All-cause mortality. ANALYTICAL APPROACH/UNASSIGNED:and mortality, overall and stratified by race and ethnicity. RESULTS/UNASSIGNED:< 0.001]). LIMITATIONS/UNASSIGNED:may not reflect individual-level exposures. CONCLUSIONS/UNASSIGNED:and reduce related mortality.

IMPORTANCE/UNASSIGNED:Residence in a disadvantaged neighborhood is a key driver of racial and ethnic disparities in the diagnosis and management of chronic diseases; however, its impact on disparities in access to waitlisting and kidney transplantation (KT) is unclear. OBJECTIVE/UNASSIGNED:To examine the association between neighborhood disadvantage and access to waitlisting and KT. DESIGN, SETTING, AND PARTICIPANTS/UNASSIGNED:This retrospective cohort study (January 1, 2015, to December 31, 2021) used a US national registry to assess adults (aged ≥18 years) with end-stage kidney disease (ESKD) and adult KT candidates. Statistical analysis was performed in March 2025. EXPOSURE/UNASSIGNED:Residential neighborhood disadvantage score (built environment disadvantage, criminal injustice, education disadvantage, unemployment, housing instability, poverty, social fragmentation, transportation barrier, and wealth inequality) ascertained by American Community Survey and other public data sources. MAIN OUTCOMES AND MEASURES/UNASSIGNED:The adjusted hazard ratios (AHRs) of waitlisting and KT (any KT, live-donor KT [LDKT], and preemptive KT) were assessed across tertiles of the neighborhood disadvantage score using cause-specific hazard models. Interaction terms were used to quantify these aforementioned associations by race and ethnicity. RESULTS/UNASSIGNED:The study included 501 444 adults with ESKD initiating dialysis (mean [SD] age, 63.9 [14.6] years; 293 937 [58.6%] male; 25 790 [5.1%] Asian [Asian American, Native Hawaiian, and Pacific Islander], 133 923 [26.7%] Black, 66 323 [13.2%] Hispanic, and 275 408 [54.9%] White) and 95 068 KT candidates on the waitlist (mean [SD] age, 53.7 [13.0] years; 60 328 [63.5%] male; 6956 [7.3%] Asian, 25 215 [26.5%] Black, 15 685 [16.5%] Hispanic, and 47 212 [49.7%] White). A total of 173 880 adults with ESKD (34.7%) and 26 718 KT candidates (28.1%) resided in high-disadvantage neighborhoods. After adjustment, adults residing in high-disadvantage neighborhoods were less likely to be waitlisted (AHR, 0.71; 95% CI, 0.69-0.72) compared with those in low-disadvantage neighborhoods. Specifically, Asian (AHR, 0.87; 95% CI, 0.80-0.95), Black (AHR, 0.68; 95% CI, 0.66-0.70), Hispanic (AHR, 0.89; 95% CI, 0.86-0.92), and White (AHR, 0.68; 95% CI, 0.66-0.71) adults in high-disadvantage neighborhoods were less likely to be waitlisted compared with White adults in low-disadvantage neighborhoods. Overall, candidates residing in high-disadvantage neighborhoods were less likely to receive any KT (AHR, 0.89; 95% CI, 0.87-0.92), LDKT (AHR, 0.65; 95% CI, 0.62-0.69), and preemptive KT (AHR, 0.62; 95% CI, 0.58-0.67). Notably, Black candidates residing in high-disadvantage neighborhoods were less likely to receive KT (AHR, 0.60; 95% CI, 0.58-0.62), LDKT (AHR, 0.23; 95% CI, 0.21-0.25), and preemptive KT (AHR, 0.22; 95% CI, 0.20-0.25) compared with White candidates in low-disadvantage neighborhoods. CONCLUSIONS AND RELEVANCE/UNASSIGNED:In this cohort study of adults with ESKD and KT candidates, residence in high-disadvantage neighborhoods was associated with reduced access to waitlisting and KT; it also was associated with persistent racial and ethnic disparities in LDKT and preemptive KT. These results suggest that to support equitable access, clinicians and transplant programs should work with social workers and community advocates to implement initiatives (eg, outreach and financial support) that address structural barriers and direct resources to affected neighborhoods.

BACKGROUND/UNASSIGNED:; environmental injustice) by racial/ethnic segregation (social injustice) on dementia diagnosis in ESKD. METHODS/UNASSIGNED:concentrations (annualized and matched to older adults' residential ZIP code at dialysis initiation) and by segregation scores (Theil's H method). FINDINGS/UNASSIGNED:and segregation. INTERPRETATION/UNASSIGNED:experienced an increased risk of dementia; this risk was particularly pronounced among individuals in high segregation and predominantly minority neighborhoods. Environmental and social injustices likely drive racial and ethnic disparities in dementia for older adults with ESKD, underscoring the need for interventions and policies to mitigate these injustices. FUNDING/UNASSIGNED:National Institutes of Health.

Older (aged ≥55 years) kidney transplant (KT) recipients diagnosed with a sleep disorder after transplantation may be at increased risk for developing dementia. Using the United States Renal Data System/Medicare claims (2010-2020), we identified 16 573 older KT recipients with a functioning graft 1-year post-KT. First-time sleep disorders and newly prescribed sleep medications were ascertained within the first year post-KT. We used cause-specific hazard models to estimate the adjusted hazard ratio of diagnosed dementia with inverse probability of treatment weights. Overall, 3615 (21.8%) KT recipients were newly diagnosed with sleep disorders. Recipients diagnosed with a sleep disorder had a 1.32-fold increased risk for dementia (95% CI:1.15-1.51); those with insomnia had a 1.56-fold increased risk (95% CI:1.20-2.03). Of those diagnosed with insomnia, only 7.5% underwent cognitive behavioral therapy for insomnia. Of the recipients, 12.9% with a sleep disorder were prescribed sleep medications. Recipients prescribed sleep medication had a 1.44-fold increased risk for dementia (95% CI:1.16-1.77). Those prescribed zolpidem, the most commonly prescribed medication (80.1%), had a 1.41-fold increased risk (95% CI:1.12-1.78) for dementia; those prescribed other sleep medications had 3.13-fold (95% CI:1.41-6.98) increased risk for dementia. Post-KT sleep disorders are modifiable dementia risk factors; medication-associated dementia risk should be weighed against other therapies such as cognitive behavioral therapy for insomnia during management.

BACKGROUND:To encourage high-quality, reduced-cost care for total joint arthroplasty (TJA), the Centers of Medicare & Medicaid Services mandated a pay-for-performance model, the Comprehensive Care for Joint Replacement (CJR), as part of the Patient Protection and Affordable Care Act (PPACA). The CJR incentivizes cost containment, and it was anticipated that its implementation would reduce access to TJA for high-cost populations. Patients with end-stage kidney disease (ESKD) undergoing kidney replacement therapy (dialysis and kidney transplant) are costly compared with healthier patients, but it was unknown whether this population lost access to hip and knee replacement because of CJR implementation. This population allows study of whether TJA is accessible for medically complex patients whose risk of surgical complications has been mitigated, as kidney transplantation improves outcomes compared with dialysis, allowing evaluation as to whether access improved when patients crossed over from dialysis to transplantation. Because all patients with ESKD are included in a mandated national registry, we can quantify whether access changed for patients who underwent dialysis and transplantation. QUESTIONS/PURPOSES/OBJECTIVE:(1) How did the rate of TJA change amid the shift to bundled payments for patients with ESKD receiving dialysis? (2) How did the rate of TJA change amid the shift to bundled payments for patients with ESKD after kidney transplant? METHODS:This was an observational cohort study from 2008 to 2018 using the United States Renal Data System, a mandatory national registry that allows for the opportunity to study all individuals with ESKD. During the study period, we identified 1,324,614 adults undergoing routine dialysis and 187,212 adult kidney transplant recipients; after exclusion for non-Medicare primary insurance (n = 785,224 for dialysis and 78,011 for transplant), patients who were 100 years or older (n = 79 and 0, respectively), those who resided outside of 50 US states and Puerto Rico (n = 781 and 87, respectively), missing dialysis status for the dialysis cohort (n = 8658), and multiorgan transplant recipients for the transplant cohort (n = 2442), our study population was 40% (529,872) of patients who underwent routine dialysis and 57% (106,672) of adult kidney transplant recipients, respectively. TJA was ascertained using Medicare Severity Diagnosis Related Groups and ICD-9 and ICD-10 codes. We divided the study period by PPACA (January 1, 2014, to March 31, 2016) and CJR (April 1, 2016, to December 31, 2018) implementation and compared the incidence of TJA by era using mixed-effects Poisson regression adjusting for calendar time and clinical and demographic variables. RESULTS:After adjustment for linear temporal trend and patient case mix, there was no evidence of association between policy implementation and the incidence of TJA. In the dialysis cohort, the adjusted incidence rate ratio (IRR) for TJA was 1.06 (95% confidence interval [CI] 0.98 to 1.14; p = 0.2) comparing PPACA with the previous period and 1.02 (95% CI 0.96 to 1.08; p = 0.6) comparing CJR with the previous periods. Similarly, in the transplant cohort, the adjusted IRR for TJA was 0.82 (95% CI 0.67 to 1.02; p = 0.07) comparing PPACA with the previous period and 1.10 (95% CI 0.94 to 1.28; p = 0.9) comparing CJR with the previous periods. CONCLUSION/CONCLUSIONS:There was no loss in access to TJA for medically complex patients receiving kidney replacement therapy. The increase in TJA incidence for patients after kidney transplant and decrease for patients receiving dialysis suggest that surgeons continued to provide care for higher risk patients whose risk of morbidity or mortality with total joint replacement has been maximally improved after transplantation. LEVEL OF EVIDENCE/METHODS:Level III, prognostic study.