Faculty Bibliography

INTRODUCTION/BACKGROUND:Early post-kidney transplant (KT) changes likely impact body composition, resulting in adverse post-KT outcomes. We estimated post-KT trajectories of computed tomography (CT)-based muscle quantity/quality and tested whether they were associated with mortality and death-censored graft loss (DCGL) among frail and nonfrail recipients. METHODS:We leveraged a cohort of 294 adult KT recipients (December 2008-February 2020) with CT measurements (muscle quantity: skeletal muscle index; muscle quality: skeletal muscle radiation attenuation). We used mixed linear regression models to estimate 3-year post-KT muscle quantity/quality trajectories. Cox proportional hazard models quantified the association between time-varying pre-/post-KT muscle mass measurements and post-KT mortality and DCGL. RESULTS:) was associated with elevated mortality risk (aHR: 2.00, 95% CI: 1.08-3.70), but not among nonfrail recipients. Among older (≥65 years) recipients, lower muscle quantity was associated with increased DCGL risk (aHR: 2.70, 95% CI: 1.04-7.04), but not among younger recipients. Lower muscle quality (per 10 HU) was associated with elevated mortality (aHR: 2.23, 95% CI: 1.61-3.08) and DCGL (aHR: 1.90, 95% CI: 1.16-3.12) risk. CONCLUSION/CONCLUSIONS:Lower pre-/post-KT muscle quantity/quality were associated with higher risks of post-KT adverse outcomes. Pre-/post-KT rehabilitation to improve muscle quantity/quality may be an effective clinical intervention to minimize risks of adverse post-KT outcomes.

IMPORTANCE/UNASSIGNED:Total particulate matter with a diameter of 2.5 µm or less (PM2.5) has been found to be associated with adverse posttransplant outcomes among kidney transplant (KT) recipients. However, PM2.5 is a complex mixture of multiple constituents, all of which have different toxicity profiles, so it is not clear which constituents are most associated with adverse outcomes among KT recipients. OBJECTIVE/UNASSIGNED:To investigate the associations between PM2.5 constituents and post-KT outcomes among KT recipients. DESIGN, SETTING, AND PARTICIPANTS/UNASSIGNED:This cohort study was conducted among patients who received a KT between January 2000 and December 2016 and lived in the contiguous United States. Follow-up continued through December 2021, and data were analyzed from August 2023 to May 2025. EXPOSURES/UNASSIGNED:Fifteen PM2.5 constituents (including elemental carbon, ammonium, nitrate, organic carbon [OC], sulfate [SO42-], bromine, calcium, copper, iron, potassium, nickel [Ni], lead [Pb], silicon, vanadium, and zinc) at the zip code of residence prior to KT, estimated from ensembled machine learning models. MAIN OUTCOMES AND MEASURES/UNASSIGNED:Adverse post-KT outcomes included acute rejection, delayed graft function (DGF), death-censored graft failure (DCGF), and mortality. The association of PM2.5 constituents and the outcome were evaluated with weighted quantile sum regressions. RESULTS/UNASSIGNED:In total, 192 587 KT recipients were included in the analysis (mean [SD] age at transplant, 51.56 [13.47] years; 75 021 [39.0%] female; 51 455 [26.7%] Black, 28 586 [14.8%] Hispanic, and 97 927 [50.8%] White). Each decile increase in the PM2.5 constituent mixture was associated with a 6.8% (95% CI, 5.8%-7.8%) and 3.6% (95% CI, 2.1%-5.1%) increase in the odds of DGF and acute rejection, respectively. OC and Ni contributed the largest weights to the observed association between PM2.5 mixture and DGF (OC: relative importance, 35.6%; Ni: relative importance, 34.4%), while Pb had the largest impact on acute rejection (relative importance, 75.0%). Each decile increase in PM2.5 constituent mixture was associated with a 4.7% (95% CI, 3.3%-6.3%) and 3.9% (95% CI, 2.5%-5.2%) increase in the hazard of DCGF and all-cause mortality, respectively. The constituent that contributed the largest weight to the observed association between PM2.5 mixture and long-term post-KT outcomes was SO42- (relative importance, 51.3%). CONCLUSIONS AND RELEVANCE/UNASSIGNED:In this cohort study, PM2.5 constituents were associated with an increased risk of adverse posttransplant outcomes among KT recipients. Of the PM2.5 constituents included in this study, SO42- contributed most to long-term outcomes, while Pb, OC, and Ni were more associated with short-term outcomes.

BACKGROUND/UNASSIGNED:) and long-term premature cognitive aging. We tested whether CMV was associated with post-KT cognitive impairment. METHODS/UNASSIGNED:In a 2-center prospective cohort study of 574 KTRs (mean age: 54.7 y), we obtained CMV donor/recipient (D/R) serostatus and measured pre- and post-KT cognitive function using the Modified Mini-Mental State Examination. We estimated post-KT global cognitive function trajectories by CMV serostatus using adjusted mixed effect models with linear spline terms. RESULTS/UNASSIGNED:(slope = 0.01 points/year; 95% CI, -1.87 to 1.89). CONCLUSIONS/UNASSIGNED:KTRs may be at elevated risk for post-KT cognitive impairment; clinicians may prioritize early interventions in this population.

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.

[This corrects the article DOI: 10.1016/j.lana.2024.100895.].

BACKGROUND:Extensive literature has highlighted the psychological burden experienced by kidney transplant recipients (KTRs) and its association with adverse outcomes. Psychological resilience can serve as a measure of baseline vulnerability, and low resilience is associated with poor mental health. We aimed to synthesize the existing literature that has explored the concept of resilience in kidney transplantation. METHODS:A scoping review was conducted due to the anticipated heterogeneity of the literature. Any empirical study that measured resilience using a validated tool in KTRs was included. Resilience could be a variable, a predictor, or an outcome. All study designs were considered with no time restrictions. RESULTS:Of the 4525 titles and abstracts screened, 14 were eligible for inclusion. Sample sizes ranged from 10 to 505 KTRs. One study exclusively focused on developing and validating a resilience scale while others used existing tools. Three studies compared resilience between different populations and the results were heterogeneous: similar resilience between KTRs and dialysis/pre-KT patients (n = 2) and another reporting better resilience in KTRs (n = 1). A decline in resilience scores after pediatric-adult transition (n = 1) and 3 months post-transplant (n = 1) was reported. In terms of outcomes, higher resilience was associated with medication adherence (n = 1), lower frailty (n = 2), and lower risk of psychopathology (n = 2). Two of the three included studies reported improvements in resilience scores with an exercise program and a resilience-enhancing program. CONCLUSIONS:Our review highlights that resilience is an underused and poorly explored construct in KTRs. We recommend explorative and interventional work as resilience is measurable and modifiable.

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.

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.