The Medical Costs of Determining Eligibility and Waiting for a Kidney Transplantation.

BACKGROUND: Recent efforts to increase access to kidney transplant (KTx) in the United States include increasing referrals to transplant programs, leading to more pretransplant services. Transplant programs reconcile the costs of these services through the Organ Acquisition Cost Center (OACC). OBJECTIVE: The aim of this study was to determine the costs associated with pretransplant services by applying microeconomic methods to OACC costs reported by transplant hospitals. RESEARCH DESIGN, SUBJECTS, AND MEASURES: For all US adult kidney transplant hospitals from 2013 through 2018 (n=193), we crosslinked the total OACC costs (at the hospital-fiscal year level) to proxy measures of volumes of pretransplant services. We used a multiple-output cost function, regressing total OACC costs against proxy measures for volumes of pretransplant services and adjusting for patient characteristics, to calculate the marginal cost of each pretransplant service. RESULTS: Over 1015 adult hospital-years, median OACC costs attributable to the pretransplant services were $5 million. Marginal costs for the pretransplant services were: initial transplant evaluation, $9k per waitlist addition; waitlist management, $2k per patient-year on the waitlist; deceased donor offer management, $1k per offer; living donor evaluation, procurement and follow-up: $26k per living donor. Longer time on dialysis among patients added to the waitlist was associated with higher OACC costs at the transplant hospital. CONCLUSIONS: To achieve the policy goals of more access to KTx, sufficient funding is needed to support the increase in volume of pretransplant services. Future studies should assess the relative value of each service and explore ways to enhance efficiency.

Immunologic Benefits of 0-antigen Mismatched Transplants: No Added Boost for Racial and Ethnic Minorities.

Background: Systemic barriers to posttransplant care, including access to immunosuppressant medications, contribute to higher rates of kidney transplant failure in racial minorities. Matching donor and recipient HLA alleles reduce allorecognition, easing reliance on immunosuppression. We hypothesize that 0-antigen mismatch transplants may provide stronger protection against graft loss in racial minorities. Methods: We compared adult, single-organ, deceased-donor kidney transplants in the United States from 2007 to 2016 by degree of HLA mismatch (0- versus ≥1-antigen mismatch). We examined time-to-allograft failure, with death as a competing event, using multivariable Weibull models, stratified by recipient race (White versus non-White), and evaluated the interaction between mismatch and recipient race. We used Kaplan-Meier imputation to account for competing risk of death. Results: We analyzed 102 114 transplants (median follow-up, 5.6 y; 16 862 graft losses, 18 994 deaths). Zero-antigen mismatch was associated with improved allograft survival (adjusted subdistribution hazard ratio [sHR] 0.80; 95% confidence interval [CI], 0.75-0.85). When stratified by recipient race, the effect of 0-antigen mismatch was more pronounced in White (unadjusted sHR 0.78; 95% CI, 0.72-0.83) versus non-White recipients (sHR 0.88; 95% CI, 0.79-0.99; interaction P = 0.04). The differential effect was attenuated after adjusting for covariates (sHR 0.78; 95% CI, 0.73-0.84 versus sHR 0.87; 95% CI, 0.77-0.98; interaction P = 0.10). Conclusions: Zero-antigen mismatch transplants conferred a 20% risk reduction in allograft loss, which was similar between non-White and White recipients. This may reflect an increased degree of mismatch at other HLA alleles and non-HLA alleles in non-White recipients or because of the extent of systemic barriers to healthcare borne by minority recipients.

Comparing and contrasting barriers in augmentative alternative communication use in nonspeaking autism and complex communication needs: multi-stakeholder perspectives.

Augmentative alternative communication (AAC) devices or systems are often prescribed to minimally verbal or nonspeaking autistic individuals and other individuals with complex communication needs to facilitate communication or as an alternative to spoken language. AAC use can result in communication gains and improved quality of life for minimally verbal or nonspeaking individuals. Despite this, AAC abandonment is high, limiting societal participation of the individual on the autism spectrum with complex communication needs. Our study is a novel exploration of the barriers of AAC use from a multi-stakeholder perspective, and a qualitative analysis of similarities and differences between stakeholders. We conducted semi-structured interviews and focus groups with 30 parent-carers, educators and clinicians currently supporting AAC users in Western Australia and analysed the data using reflexive thematic analysis. Barriers from each stakeholder group were coded, resulting in 17 subthemes forming five main themes common to all stakeholders: Stakeholder Knowledge, Stakeholder Attitudes and Stigma, Resources, AAC User Engagement, and Device Fit. Contrasting perspectives included actual and perceived stigma associated with AAC use (parent-carers vs clinicians); different struggles with resources and knowledge (parent-carers vs clinicians and educators); and a lack of clinician communication in the processes that determined AAC-fit for school environments (educators only). Findings are discussed in the context of improving inter-stakeholder collaboration and capacity building in Australian health service and practice to better support minimally verbal or nonspeaking autistic individuals and individuals with complex communication needs. Suggestions are also offered for communication partner training.

Cognitive and neuroscientific perspectives of healthy ageing.

With dementia incidence projected to escalate significantly within the next 25 years, the United Nations declared 2021-2030 the Decade of Healthy Ageing, emphasising cognition as a crucial element. As a leading discipline in cognition and ageing research, psychology is well-equipped to offer insights for translational research, clinical practice, and policy-making. In this comprehensive review, we discuss the current state of knowledge on age-related changes in cognition and psychological health. We discuss cognitive changes during ageing, including (a) heterogeneity in the rate, trajectory, and characteristics of decline experienced by older adults, (b) the role of cognitive reserve in age-related cognitive decline, and (c) the potential for cognitive training to slow this decline. We also examine ageing and cognition through multiple theoretical perspectives. We highlight critical unresolved issues, such as the disparate implications of subjective versus objective measures of cognitive decline and the insufficient evaluation of cognitive training programs. We suggest future research directions, and emphasise interdisciplinary collaboration to create a more comprehensive understanding of the factors that modulate cognitive ageing.

Validation of a Core Patient-Reported Outcome Measure for Life Participation in Kidney Transplant Recipients: the SONG Life Participation Instrument.

Introduction: Life participation has been established as a critically important core for trials in kidney transplantation. We aimed to validate a patient-reported outcome measure for life participation in kidney transplant recipients. Methods: A psychometric evaluation of the Standardized Outcomes in Nephrology life participation (SONG-LP) measure was conducted in adult kidney transplant recipients. The measure includes 4 items of life participation (leisure, family, work, and social) each with a 5-point Likert scale. Each item is scored from 0 (never) to 4 (always) and the summary measure score the average of each item. Results: A total of 249 adult kidney transplant recipients from 20 countries participated. The SONG-LP instrument demonstrated internal consistency (Cronbach's α = 0.87; 95% confidence intervals [CI]: 0.83-0.90, baseline) and test-retest reliability over 1 week (intraclass correlation coefficient of 0.62; 95% CI: 0.54-0.70). There was moderate to high correlation (0.65; 95% CI: 0.57-0.72) with the PROMIS Ability to Participate in Social Roles and Activities Short Form 8a that assessed a similar construct, and moderate correlation with measures that assessed related concepts (i.e., EQ5D 0.57; 95% CI: 0.49-0.65), PROMIS Cognitive Functional Abilities Subset Short Form 4a (0.40; 95% CI: 0.29-0.50). Conclusion: The SONG-LP instrument is a simple, internally consistent, reliable measure for kidney transplant recipients and correlates with similar measures. Routine incorporation in clinical trials will ensure consistent and appropriate assessment of life participation for informed patient-centered decision-making.

Comparison of online and offline applications of dual-site transcranial alternating current stimulation (tACS) over the pre-supplementary motor area (preSMA) and right inferior frontal gyrus (rIFG) for improving response inhibition.

The efficacy of transcranial alternating current stimulation (tACS) is thought to be brain state-dependent, such that tACS during task performance would be hypothesised to offer greater potential for improving performance compared to tACS at rest. However, to date, no empirical study has tested this postulation. The current study compared the effects of dual-site beta tACS applied during a stop signal task (online) to the effects of the same tACS protocol applied prior to the task (offline) and a sham control stimulation in 53 young, healthy adults (32 female; 18-35 yrs). The right inferior frontal gyrus (rIFG) and centre (midline) of the pre-supplementary motor area (preSMA), which are thought to play critical roles in action cancellation, were simultaneously stimulated, sending phase-synchronised stimulation for 15 min with the aim of increasing functional connectivity. The offline group showed significant within-group improvement in response inhibition without showing overt task-related changes in functional connectivity measured with EEG connectivity analysis, suggesting offline tACS is efficacious in inducing behavioural changes potentially via a post-stimulation early plasticity mechanism. In contrast, neither the online nor sham group showed significant improvements in response inhibition. However, EEG connectivity analysis revealed significantly increased task-related functional connectivity following online stimulation and a medium effect size observed in correlation analyses suggested that an increase in functional connectivity in the beta band at rest was potentially associated with an improvement in response inhibition. Overall, the results indicate that both online and offline dual-site beta tACS can be beneficial in improving inhibitory control via distinct underlying mechanisms.

An 8-week compassion and mindfulness-based exposure therapy program improves posttraumatic stress symptoms.

The persistence of posttraumatic stress symptoms (PTSS) can be debilitating. However, many people experiencing such symptoms may not qualify for or may not seek treatment. Potentially contributing to ongoing residual symptoms of PTSS is emotion dysregulation. Meanwhile, the research area of mindfulness and compassion has grown to imply emotion regulation as one of its underlying mechanisms; yet, its influence on emotion regulation in PTSS cohort is unknown. Here, we explored the potential effectiveness of an 8-week Compassion-oriented and Mindfulness-based Exposure Therapy (CoMET) for individuals with PTSS using a waitlist control design. A total of 28 individuals (27 females, age range = 18-39 years) participated in the study (17 CoMET; 11 waitlist control). Following CoMET, participants reported significant decreases in PTSS severity (from clinical to non-clinical levels), emotion dysregulation and experiential avoidance, as well as significant increases in mindfulness, self-compassion and quality of life. Electroencephalogram-based brain network connectivity analysis revealed an increase in alpha-band connectivity following CoMET in a network that includes the amygdala, suggesting that CoMET successfully induced changes in functional connectivity between brain regions that play a crucial role in emotion regulation. In sum, the current study demonstrated promising intervention outcomes of CoMET in effectively alleviating the symptoms of PTSS via enhanced emotion regulation.

Deceased Donor Kidney Transplantation for Older Transplant Candidates: A New Microsimulation Model for Determining Risks and Benefits.

BACKGROUND: Under the current US kidney allocation system, older candidates receive a disproportionately small share of deceased donor kidneys despite a reserve of potentially usable kidneys that could shorten their wait times. To consider potential health gains from increasing access to kidneys for these candidates, we developed and calibrated a microsimulation model of the transplantation process and long-term outcomes for older deceased donor kidney transplant candidates. METHODS: We estimated risk equations for transplant outcomes using the Scientific Registry of Transplant Recipients (SRTR), which contains data on all US transplants (2010-2019). A microsimulation model combined these equations to account for competing events. We calibrated the model to key transplant outcomes and used acceptance sampling, retaining the best-fitting 100 parameter sets. We then examined life expectancy gains from allocating kidneys even of lower quality across patient subgroups defined by age and designated race/ethnicity. RESULTS: The best-fitting 100 parameter sets (among 4,000,000 sampled) enabled our model to closely match key transplant outcomes. The model demonstrated clear survival benefits for those who receive a deceased donor kidney, even a lower quality one, compared with remaining on the waitlist where there is a risk of removal. The expected gain in survival from receiving a lower quality donor kidney was consistent gains across age and race/ethnic subgroups. LIMITATIONS: Limited available data on socioeconomic factors. CONCLUSIONS: Our microsimulation model accurately replicates a range of key kidney transplant outcomes among older candidates and demonstrates that older candidates may derive substantial benefits from transplantation with lower quality kidneys. This model can be used to evaluate policies that have been proposed to address concerns that the current system disincentivizes deceased donor transplants for older patients. HIGHLIGHTS: The microsimulation model was consistent with the data after calibration and accurately simulated the transplantation process for older deceased donor kidney transplant candidates.There are clear survival benefits for older transplant candidates who receive deceased donor kidneys, even lower quality ones, compared with remaining on the waitlist.This model can be used to evaluate policies aimed at increasing transplantation among older candidates.

Association of Pretransplant Coronary Heart Disease Testing With Early Kidney Transplant Outcomes.

Importance: Testing for coronary heart disease (CHD) in asymptomatic kidney transplant candidates before transplant is widespread and endorsed by various professional societies, but its association with perioperative outcomes is unclear. Objective: To estimate the association of pretransplant CHD testing with rates of death and myocardial infarction (MI). Design, Setting, and Participants: This retrospective cohort study included all adult, first-time kidney transplant recipients from January 2000 through December 2014 in the US Renal Data System with at least 1 year of Medicare enrollment before and after transplant. An instrumental variable (IV) analysis was used, with the program-level CHD testing rate in the year of the transplant as the IV. Analyses were stratified by study period, as the rate of CHD testing varied over time. A combination of US Renal Data System variables and Medicare claims was used to ascertain exposure, IV, covariates, and outcomes. Exposures: Receipt of nonurgent invasive or noninvasive CHD testing during the 12 months preceding kidney transplant. Main Outcomes and Measures: The primary outcome was a composite of death or acute MI within 30 days of after kidney transplant. Results: The cohort comprised 79 334 adult, first-time kidney transplant recipients (30 147 women [38%]; 25 387 [21%] Black and 48 394 [61%] White individuals; mean [SD] age of 56 [14] years during 2012 to 2014). The primary outcome occurred in 4604 patients (244 [5.3%]; 120 [2.6%] death, 134 [2.9%] acute MI). During the most recent study period (2012-2014), the CHD testing rate was 56% in patients in the most test-intensive transplant programs (fifth IV quintile) and 24% in patients at the least test-intensive transplant program (first IV quintile, P < .001); this pattern was similar across other study periods. In the main IV analysis, compared with no testing, CHD testing was not associated with a change in the rate of primary outcome (rate difference, 1.9%; 95% CI, 0%-3.5%). The results were similar across study periods, except for 2000 to 2003, during which CHD testing was associated with a higher event rate (rate difference, 6.8%; 95% CI, 1.8%-12.0%). Conclusions and Relevance: The results of this cohort study suggest that pretransplant CHD testing was not associated with a reduction in early posttransplant death or acute MI. The study findings potentially challenge the ubiquity of CHD testing before kidney transplant and should be confirmed in interventional studies.

Infection, Rejection, and the Connection.

Solid organ transplantation is a life-saving treatment for people with end-stage organ disease. Immune-mediated transplant rejection is a common complication that decreases allograft survival. Although immunosuppression is required to prevent rejection, it also increases the risk of infection. Some infections, such as cytomegalovirus and BK virus, can promote inflammatory gene expression that can further tip the balance toward rejection. BK virus and other infections can induce damage that resembles the clinical pathology of rejection, and this complicates accurate diagnosis. Moreover, T cells specific for viral infection can lead to rejection through heterologous immunity to donor antigen directly mediated by antiviral cells. Thus, viral infections and allograft rejection interact in multiple ways that are important to maintain immunologic homeostasis in solid organ transplant recipients. Better insight into this dynamic interplay will help promote long-term transplant survival.

Trends in Coronary Artery Disease Screening before Kidney Transplantation.

Background: Coronary artery disease (CAD) screening in asymptomatic kidney transplant candidates is widespread but not well supported by contemporary cardiology literature. In this study we describe temporal trends in CAD screening before kidney transplant in the United States. Methods: Using the United States Renal Data System, we examined Medicare-insured adults who received a first kidney transplant from 2000 through 2015. We stratified analysis on the basis of whether the patient's comorbidity burden met guideline definitions of high risk for CAD. We examined temporal trends in nonurgent CAD tests within the year before transplant and the composite of death and nonfatal myocardial infarction in the 30 days after transplant. Results: Of 94,832 kidney transplant recipients, 37,139 (39%) underwent at least one nonurgent CAD test in the 1 year before transplant. From 2000 to 2015, the transplant program waitlist volume had increased as transplant volume stayed constant, whereas patients in the later eras had a slightly higher comorbidity burden (older, longer dialysis vintage, and a higher prevalence of diabetes mellitus and CAD). The likelihood of CAD test in the year before transplant increased from 2000 through 2003 and remained relatively stable thereafter. When stratified by CAD risk status, test rates decreased modestly in patients who were high risk but remained constant in patients who were low risk after 2008. Death or nonfatal myocardial infarction within 30 days after transplant decreased from 3% in 2000 to 2% in 2015. Nuclear perfusion scan was the most frequent modality of testing throughout the examined time periods. Conclusions: CAD testing rates before kidney transplantation have remained constant from 2000 through 2015, despite widespread changes in cardiology guidelines and practice.

Trends in Cost Attributable to Kidney Transplantation Evaluation and Waiting List Management in the United States, 2012-2017.

Importance: While recent policy reforms aim to improve access to kidney transplantation for patients with end-stage kidney disease, the cost implications of kidney waiting list expansion are not well understood. The Organ Acquisition Cost Center (OACC) is the mechanism by which Medicare reimburses kidney transplantation programs, at cost, for costs attributable to kidney transplantation evaluation and waiting list management, but these costs have not been well described to date. Objectives: To describe temporal trends in mean OACC costs per kidney transplantation and to identify factors most associated with cost. Design, Setting, and Participants: This economic evaluation included all kidney transplantation waiting list candidates and recipients in the United States from 2012 to 2017. A population-based study of cost center reports was conducted using data from all Center of Medicare & Medicaid-certified transplantation hospitals. Data analysis was conducted from June to August 2021. Exposures: Year, local price index, transplantation and waiting list volume of transplantation program, and comorbidity burden. Main Outcomes and Measures: Mean OACC costs per kidney transplantation. Results: In 1335 hospital-years from 2012 through 2017, Medicare's share of OACC costs increased from $0.95 billion in 2012 to $1.32 billion in 2017 (3.7% of total Medicare End-Stage Renal Disease program expenditure). Median (IQR) OACC costs per transplantation increased from $81 000 ($66 000 to $103 000) in 2012 to $100 000 ($82 000 to $125 000) in 2017. Kidney organ procurement costs contributed to 36% of mean OACC costs per transplantation throughout the study period. During the study period, transplantation hospitals experienced increases in kidney waiting list volume, kidney waiting list active volume, kidney transplantation volume, and comorbidity burden. For a median-sized transplantation program, mean OACC costs per transplantation decreased with more transplants (-$3500 [95% CI, -$4300 to -$2700] per 10 transplants; P < .001) and increased with year ($4400 [95% CI, $3500 to $5300] per year; P < .001), local price index ($1900 [95% CI, $200 to $3700] per 10-point increase; P = .03), patients listed active on the waiting list ($3100 [95% CI, $1700 to $4600] per 100 patients; P < .001), and patients on the waiting list with high comorbidities ($1500 [9% CI, $600 to $2500] per 1% increase in proportion of waitlisted patients with the highest comorbidity score; P = .002). Conclusions and Relevance: In this study, OACC costs increased at 4% per year from 2012 to 2017 and were not solely attributable to the cost of organ procurement. Expanding the waiting list will likely contribute to further increases in the mean OACC costs per transplantation and substantially increase Medicare liability.

Influence of tDCS over right inferior frontal gyrus and pre-supplementary motor area on perceptual decision-making and response inhibition: A healthy ageing perspective.

A wide body of literature suggests that transcranial direct current stimulation (tDCS) administered over the prefrontal cortex can improve executive function - including decision-making and inhibitory control - in healthy young adults. However, the effects of tDCS in older adults are largely unknown. Here, using a double-blind, sham-controlled approach, changes in a combined perceptual decision-making and inhibitory control task were assessed before and after the application of tDCS (1 mA, 20 minute) targeting the right inferior frontal gyrus (rIFG) or pre-supplementary motor area (preSMA) in 42 young (18-34 years) and 41 older (60-80 years) healthy adults. Compared to sham stimulation, anodal tDCS over the preSMA improved decision-making speed for both age groups. Furthermore, the inhibitory control performance of older and younger adults was improved by preSMA and rIFG stimulation, respectively. This study provides evidence that tDCS can improve both perceptual decision-making and inhibitory control in healthy older adults, with the causal role of the preSMA and rIFG regions in cognitive control appearing to vary as a function of healthy ageing.

Racial Disparities in Pediatric Kidney Transplantation under the New Kidney Allocation System in the United States.

BACKGROUND AND OBJECTIVES: In December 2014, the Kidney Allocation System (KAS) was implemented to improve equity in access to transplantation, but preliminary studies in children show mixed results. Thus, we aimed to assess how the 2014 KAS policy change affected racial and ethnic disparities in pediatric kidney transplantation access and related outcomes. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: We performed a retrospective cohort study of children <18 years of age active on the kidney transplant list from 2008 to 2019 using the Scientific Registry of Transplant Recipients. Log-logistic accelerated failure time models were used to determine the time from first activation on the transplant list and the time on dialysis to deceased donor transplant, each with KAS era or race and ethnicity as the exposure of interest. We used logistic regression to assess odds of delayed graft function. Log-rank tests assessed time to graft loss within racial and ethnic groups across KAS eras. RESULTS: All children experienced longer wait times from activation to transplantation post-KAS. In univariable analysis, Black and Hispanic children and other children of color experienced longer times from activation to transplant compared with White children in both eras; this finding was largely attenuated after multivariable analysis (time ratio, 1.16; 95% confidence interval, 1.01 to 1.32; time ratio, 1.13; 95% confidence interval, 1.00 to 1.28; and time ratio, 1.17; 95% confidence interval, 0.96 to 1.41 post-KAS, respectively). Multivariable analysis also showed that racial and ethnic disparities in time from dialysis initiation to transplantation in the pre-KAS era were mitigated in the post-KAS era. There were no disparities in odds of delayed graft function. Black and Hispanic children experienced longer times with a functioning graft in the post-KAS era. CONCLUSIONS: No racial and ethnic disparities from activation to deceased donor transplantation were seen before or after implementation of the KAS in multivariable analysis, whereas time on dialysis to transplantation and odds of short-term graft loss improved in equity after the implementation of the KAS, without compromising disparities in delayed graft function. PODCAST: This article contains a podcast at https://www.asn-online.org/media/podcast/CJASN/2021_12_07_CJN06740521.mp3.

Functional Consequences of Memory Inflation after Solid Organ Transplantation.

CMV is a major infectious complication following solid organ transplantation. Reactivation of CMV leads to memory inflation, a process in which CD8 T cells expand over time. Memory inflation is associated with specific changes in T cell function, including increased oligoclonality, decreased cytokine production, and terminal differentiation. To address whether memory inflation during the first year after transplantation in human subjects alters T cell differentiation and function, we employed single-cell-matched TCRαß and targeted gene expression sequencing. Expanded T cell clones exhibited a terminally differentiated, immunosenescent, and polyfunctional phenotype whereas rare clones were less differentiated. Clonal expansion occurring between pre- and 3 mo posttransplant was accompanied by enhancement of polyfunctionality. In contrast, polyfunctionality and differentiation state were largely maintained between 3 and 12 mo posttransplant. Highly expanded clones had a higher degree of polyfunctionality than rare clones. Thus, CMV-responsive CD8 T cells differentiated during the pre- to posttransplant period then maintained their differentiation state and functional capacity despite posttransplant clonal expansion.

Immunosuppression Considerations for Older Kidney Transplant Recipients.

PURPOSE OF REVIEW: While kidney transplantation improves the long-term survival of the majority of patients with end-stage kidney disease (ESKD), age-related immune dysfunction and associated comorbidities make older transplant recipients more susceptible to complications related to immunosuppression. In this review, we discuss appropriate management of immunosuppressive agents in older adults to minimize adverse events, avoid acute rejection, and maximize patient and graft survival. RECENT FINDINGS: Physiological changes associated with senescence can impact drug metabolism and increase the risk of posttransplant infection and malignancy. Clinical trials assessing the safety and efficacy of immunosuppressive agents in older adults are lacking. Recent findings from U.S. transplant registry-based studies suggest that risk-adjusted death-censored graft failure is higher among older patients who received antimetabolite avoidance, mammalian target of rapamycin inhibitor (mTORi)-based, and cyclosporine-based regimens. Observational data suggest that risk-adjusted mortality may be increased in older patients who receive mTORi-based and cyclosporine-based regimens but lower in those managed with T-cell induction and maintenance steroid avoidance/withdrawal. SUMMARY: Tailored immunosuppression management to improve patient and graft survival in older transplant recipients is an important goal of personalized medicine. Lower intensity immunosuppression, such as steroid-sparing regimens, appear beneficial whereas mTORi- and cyclosporine-based maintenance are associated with greater potential for adverse effects. Prospective clinical trials to assess the safety and efficacy of immunosuppression agents in older recipients are urgently needed.

Karnofsky Performance Score-Failure to Thrive as a Frailty Proxy?

Among patients listed for kidney transplantation, the Karnofsky Performance Status (KPS) Scale has been used as a proxy for frailty and proposed as a predictor of long-term posttransplant outcomes. The KPS is required by the Organ Procurement and Transplantation Network for all transplants; however, the interrater reliability of KPS reporting in kidney transplant candidates has not been well investigated, and there is concern regarding limitations of using KPS that may influence transplant eligibility. METHODS: We performed an observational study using existing Scientific Registry of Transplant Recipients data from 2006 to 2020 to examine the variability, reliability, and trends in the KPS among patients on the kidney transplant waitlist. RESULTS: Our analysis included 8197 kidney transplant candidates with >1 KPS in a 3-mo period. We observed 2-7 scores per patient with an average score of 78.9 (SD = 12, 95% confidence interval, 78.8-79.1). We found substantial variability in KPS reporting, in which 27% of the patients had scores that varied widely with 20-80 points in difference. Interrater reliability in the 10-point scale was poor (30%). When using a condensed 4-category scale (disabled, requires assistance, capable of self-care, normal activity), 38% of patients experienced at least a 1-category shift in their score. CONCLUSIONS: The lack of reliability in KPS reporting raises concerns when applying the KPS as a proxy for frailty and a metric to be considered when evaluating candidacy for kidney transplantation.

Performance versus Risk Factor-Based Approaches to Coronary Artery Disease Screening in Waitlisted Kidney Transplant Candidates.

INTRODUCTION: Current screening algorithms for coronary artery disease (CAD) before kidney transplantation result in many tests but few interventions. OBJECTIVE: The aim of this study was to study the utility of 6-minute walk test (6MWT), an office-based test of cardiorespiratory fitness, for risk stratification in this setting. METHODS: We enrolled 360 patients who are near the top of the kidney transplant waitlist at our institution. All patients underwent CAD evaluation irrespective of 6MWT results. We examined the association between 6MWT and time to CAD-related events (defined as cardiac death, revascularization, nonfatal myocardial infarction, and removal from the waitlist for CAD), treating noncardiac death and waitlist removal for non-CAD reasons as competing events. RESULTS: The 6MWT-based approach designated approximately 45% of patients as "low risk," whereas a risk factor- or symptom-based approach designated 14 and 81% of patients as "low risk," respectively. The 6MWT-based approach was not significantly associated with CAD-related events within 1 year (subproportional hazard ratio [sHR] 1.00 [0.90-1.11] per 50 m) but was significantly associated with competing events (sHR 0.70 [0.66-0.75] per 50 m). In a companion analysis, removing waitlist status from consideration, 6MWT result was associated with the development of CAD-related events (sHR 0.92 [0.84-1.00] per 50 m). CONCLUSIONS: The 6MWT designates fewer patients as high risk and in need of further testing (compared to risk factor-based approaches), but its utility as a pure CAD risk stratification tool is modulated by the background waitlist removal rate. CAD screening before kidney transplant should be tailored according to a patient's actual chance of receiving a transplant.

The organ procurement costs of expanding deceased donor organ acceptance criteria: Evidence from a cost function model.

A potential solution to the deceased donor organ shortage is to expand donor acceptability criteria. The procurement cost implications of using nonstandard donors is unknown. Using 5 years of US organ procurement organization (OPO) data, we built a cost function model to make cost projections: the total cost was the dependent variable; production outputs, including the number of donors and organs procured, were the independent variables. In the model, procuring one kidney or procuring both kidneys from double/en bloc transplantation from a single-organ donor resulted in a marginal cost of $55 k (95% confidence interval [CI] $28 k, $99 k) per kidney, and procuring only the liver from a single-organ donor results in a marginal cost of $41 k (95% CI $12 k, $69 k) per liver. Procuring two kidneys for two candidates from a donor lowered the marginal cost to $36 k (95% CI $22 k, $66 k) per kidney, and procuring two kidneys and a liver lowers the marginal cost to $24 k (95% CI $17 k, $45 k) per organ. Economies of scale were observed, where high OPO volume was correlated with lower costs. Despite higher cost per organ than for standard donors, kidney transplantation from nonstandard donors remained cost-effective based on contemporary US data.

Association of physical function and performance with peak VO2 in elderly patients with end stage kidney disease.

BACKGROUND: Physical function is impaired in end stage renal disease (ESRD). Various instruments have been used to assess the functional capabilities and health status of patients with ESRD, but it is not known which has the best association with peak VO2. AIMS: To assess the association between functional measures in ESRD. METHODS: Thirty nine elderly ESRD patients were evaluated with commonly used functional, health status, and quality of life measures, including maximal cardiopulmonary exercise testing (CPET), 6-min walk (6MWT), sit-to-stand test (STS), Veterans Specific Activity Questionnaire (VSAQ), upper and lower body strength, pulmonary function tests, and body composition determined by dual X-ray absorptiometry. The association between performance on these functional tools, clinical variables, and exercise test responses was assessed, and a non-exercise test multivariate model was developed to predict peak VO2. RESULTS: Peak VO2 was modestly related to VSAQ score (r = 0.59, p < 0.01), indices of upper and lower body strength (r = 0.45, p < 0.01 for both), and FEV1 (r = 0.51, p < 0.01). Functional and quality of life questionnaires were generally poorly related to one another and to peak VO2. In a multivariate model, 6MWT performance, forced expiratory volume in 1 s (FEV1), and VSAQ score were the best predictors of peak VO2, yielding a multiple R = 0.82, accounting for 67% of the variance in peak VO2. CONCLUSION: Exercise capacity can be reasonably estimated using non-exercise test variables in patients with ESRD, including a symptom questionnaire (VSAQ), 6MWT and FEV1. CLINICAL TRIAL INFORMATION: ClinicalTrials.gov identifier: NCT01990495. Registered Nov 21, 2013.