Analysis of the Wait List and Deaths Among Candidates Waiting for a Kidney Transplant

Expanding the access to kidney transplantation: Strategies for kidney transplant programs

Kidney transplantation is the most successful kidney replacement therapy available, resulting in improved recipient survival and societal cost savings. Yet, nearly 70 years after the first successful kidney transplant, there are still numerous barriers and untapped opportunities that constrain the access to transplant. The literature describing these barriers is extensive, but the practices and processes to solve them are less clear. Solutions must be multidisciplinary and be the product of strong partnerships among patients, their networks, health care providers, and transplant programs. Transparency in the referral, evaluation, and listing process as well as organ selection are paramount to build such partnerships. Providing early culturally congruent and patient-centered education as well as maximizing the use of local resources to facilitate the transplant work up should be prioritized. Every opportunity to facilitate pre-emptive kidney transplantation and living donation must be taken. Promoting the use of telemedicine and kidney paired donation as standards of care can positively impact the work up completion and maximize the chances of a living donor kidney transplant.

A cross-validation statistical framework for asymmetric data integration

The proliferation of biobanks and large public clinical data sets enables their integration with a smaller amount of locally gathered data for the purposes of parameter estimation and model prediction. However, public data sets may be subject to context-dependent confounders and the protocols behind their generation are often opaque; naively integrating all external data sets equally can bias estimates and lead to spurious conclusions. Weighted data integration is a potential solution, but current methods still require subjective specifications of weights and can become computationally intractable. Under the assumption that local data are generated from the set of unknown true parameters, we propose a novel weighted integration method based upon using the external data to minimize the local data leave-one-out cross validation (LOOCV) error. We demonstrate how the optimization of LOOCV errors for linear and Cox proportional hazards models can be rewritten as functions of external data set integration weights. Significant reductions in estimation error and prediction error are shown using simulation studies mimicking the heterogeneity of clinical data as well as a real-world example using kidney transplant patients from the Scientific Registry of Transplant Recipients.

Frailty and the Kidney Transplant Wait List: Protocol for a Multicenter Prospective Study

Background:

Understanding how frailty affects patients listed for transplantation has been identified as a priority research need. Frailty may be associated with a high risk of death or wait-list withdrawal, but this has not been evaluated in a large multicenter cohort of Canadian wait-listed patients.

Objective:

The primary objective is to evaluate whether frailty is associated with death or permanent withdrawal from the transplant wait list. Secondary objectives include assessing whether frailty is associated with hospitalization, quality of life, and the probability of being accepted to the wait list.

Design:

Prospective cohort study.

Setting:

Seven sites with established renal transplant programs that evaluate patients for the kidney transplant wait list.

Patients:

Individuals who are being considered for the kidney transplant wait list.

Measurements:

We will assess frailty using the Fried Phenotype, a frailty index, the Short Physical Performance Battery, and the Clinical Frailty Scale at the time of listing for transplantation. We will also assess frailty at the time of referral to the wait list and annually after listing in a subgroup of patients.

Methods:

The primary outcome of the composite of time to death or permanent wait-list withdrawal will be compared between patients who are frail and those who are not frail and will account for the competing risks of deceased and live donor transplantation. Secondary outcomes will include number of hospitalizations and length of stay, and in a subset, changes in frailty severity over time, change in quality of life, and the probability of being listed. Recruitment of 1165 patients will provide >80% power to identify a relative hazard of ≥1.7 comparing patients who are frail to those who are not frail for the primary outcome (2-sided α = .05), whereas a more conservative recruitment target of 624 patients will provide >80% power to identify a relative hazard of ≥2.0.

Results:

Through December 2019, 665 assessments of frailty (inclusive of those for the primary outcome and all secondary outcomes including repeated measures) have been completed.

Limitations:

There may be variation across sites in the processes of referral and listing for transplantation that will require consideration in the analysis and results.

Conclusions:

This study will provide a detailed understanding of the association between frailty and outcomes for wait-listed patients. Understanding this association is necessary before routinely measuring frailty as part of the wait-list eligibility assessment and prior to ascertaining the need for interventions that may modify frailty.

Trial Registration:

Not applicable as this is a protocol for a prospective observational study.

Uncontrolled donation after circulatory death improves access to kidney transplantation: A decision analysis

AIM

Uncontrolled donation after cardiac death (uDCD) remains an underutilized source of kidney allografts in the United States. The objective of this study was to estimate the impact of the implementation of a uDCD program on transplantation rates and long-term survival for patients with end-stage renal disease (ESRD) in the United States.

METHODS

A decision-analytic Markov state transition model was created using medical decision-making software (DATA 3.5; TreeAge Software, Inc) to estimate the impact of an uDCD program on transplantation rates and patient survival. Additionally, sensitivity analysis of uDCD donor pool increase was modeled. All model statistic parameters were extracted from the literature.

RESULTS

A uDCD program increased the rate of transplant at 10 years (37.8%, Accept uDCD group, vs 35.9%, Reject uDCD group). At 10 years, overall survival for Accept uDCD was 55.6% compared to 54.8% in the Reject uDCD.

CONCLUSIONS

Uncontrolled DCD improves access to transplant for ESRD patients on the kidney transplant waitlist, thereby improving long-term survival.

Survival analysis of patients in the waiting list for kidney transplantation in terms of competing risks

Aim: to analyze the survival of patients on the waiting list for kidney transplantation and the results of transplantation depending on the duration of waiting.

Materials and methods. We performed a retrospective observational analysis that included 1,197 patients on the waiting list. The end point was exclusion from the waiting list (WL). The causes for exclusion (death, exclusion due to deterioration of the comorbid background or transplantation) were considered in terms of competing risks.

Results. In total, 72.5% of patients reached the end point: 21.1% of them died, 11% were excluded, and 40.4% underwent transplantation. Kaplan–Meier estimate showed that cumulative risk of death was 80.4% [95% CI 77.9; 88.6], of exclusion was 77.9% [95% CI 65.4; 88.2], of transplantation was 63.6% [95% CI 58.3; 69] after 10 years on the waiting list. However, such an assessment cannot be directly interpreted as a prediction of the relevant event risk of occurrence for the patient in the WL, because it does not take into account competing events. According to a balanced assessment of the competing risks (Fine and Gray estimate), cumulative incidence was 30.9% (95% CI 27.7; 34.2) for death, 18.2% [95% CI 15.5; 21.1] for exclusion and 49.4% [95% CI 46; 52.6%] for transplantation after 10 years on WL. The probability of transplantation was significantly higher than the risk of death up to and including 5 years of waiting (incidence rate ratio – IRR 1.769 [95% CI 1.098; 2.897]). When waiting 7 to 8 years, the probability of transplantation was less than the risk of death: IRR 0.25 (95% CI 0.093; 0.588; p = 0.0009). Of the 483 recipients, 61 died and 119 returned to dialysis. The risk of graft loss after 10 years was 68.5% [95% CI 57.5; 79.1] and the risk of death of a recipient with a functioning graft was 48.3% [95% CI 34.7; 63] according to Kaplan–Meier estimate. The cumulative incidence of the method was 30.8% [95% CI 23.3; 38.5%] and 55.7% [95% CI 46.6; 63.5%] according to Fine and Gray estimate, respectively. The risk of death after transplantation increases significantly when waiting for more than 6 years – IRR 4.325 [95% CI 1.649; 10.47], p = 0.0045 relative to a shorter waiting period. With an increase in the waiting period, the comorbid background (CIRS scale) deteriorates significantly, even adjusted for the initial patient condition: the partial correlation r = 0.735; p < 0.0001.

Conclusion. 1. In the context of competing risks, the Fine and Gray estimate gives a more balanced risk assessment compared to the Kaplan–Meier method. 2. Increasing the waiting time for transplantation significantly increases the risk of death of the candidate on the waiting list and reduces the probability of transplantation, as well as increases the risk of death of the recipient after transplantation. Apparently, this is mainly due to the deterioration of the comorbid background.

Mortality in Elderly Waiting-List Patients Versus Age-Matched Kidney Transplant Recipients: Where is the Risk?

The number of elderly patients on the waiting list (WL) for kidney transplantation (KT) has risen significantly in recent years. Because KT offers a better survival than dialysis therapy, even in the elderly, candidates for KT should be selected carefully, particularly in older waitlisted patients. Identification of risk factors for death in WL patients and prediction of both perioperative risk and long-term post-transplant mortality are crucial for the proper allocation of organs and the clinical management of these patients in order to decrease mortality, both while on the WL and after KT. In this review, we examine the clinical results in studies concerning: a) risk factors for mortality in WL patients and KT recipients; 2) the benefits and risks of performing KT in the elderly, comparing survival between patients on the WL and KT recipients; and 3) clinical tools that should be used to assess the perioperative risk of mortality and predict long-term post-transplant survival. The acknowledgment of these concerns could contribute to better management of high-risk patients and prophylactic interventions to prolong survival in this particular population, provided a higher mortality is assumed.

Peripheral Vascular Disease and Death in Southern European Kidney Transplant Candidates: A Competing Risk Modeling Approach

BACKGROUND

The association between peripheral vascular disease (PVD) and survival among kidney transplant (KT) candidates is uncertain.

METHODS

We assessed 3851 adult KT candidates from the Andalusian Registry between 1984 and 2012. Whereas 1975 patients received a KT and were censored, 1876 were on the waiting list at any time. Overall median waitlist time was 21.2 months (interquartile range, 11-37.4). We assessed the association between PVD and mortality in waitlisted patients using a multivariate Cox regression model, with a competing risk approach as a sensitivity analysis.

RESULTS

Peripheral vascular disease existed in 308 KT candidates at waitlist entry. The prevalence of PVD among nondiabetic and diabetic patients was 4.5% and 25.3% (P < 0.0001). All-cause mortality was higher in candidates with PVD (45% vs 21%; P < 0.0001). Among patients on the waiting list (n = 1876) who died (n = 446; 24%), 272 (61%) died within 2 years after listing. Cumulative incidence of all-cause mortality at 2 years in patients with and without PVD was 23% and 6.4%, respectively (P < 0.0001); similar differences were observed in patients with and without diabetes. By competing risk models, PVD was associated with a 1.9-fold increased risk of mortality (95% confidence interval [95% CI], 1.4-2.5). This association was stronger in waitlisted patients without cardiac disease (subhazard ratio, 2.2; 95% CI, 1.6-3.1) versus those with cardiac disorders (subhazard ratio, 1.5; 95% CI, 0.9-2.5). No other significant interactions were observed. Similar results were seen after excluding diabetics.

CONCLUSIONS

Peripheral vascular disease is a strong predictor of mortality in KT candidates. Identification of PVD at list entry may contribute to optimize targeted therapeutic interventions and help prioritize high-risk KT candidates.

Linguistic Isolation and Access to the Active Kidney Transplant Waiting List in the United States

BACKGROUND AND OBJECTIVES

Waitlist inactivity is a barrier to transplantation, because inactive candidates cannot receive deceased donor organ offers. We hypothesized that temporarily inactive kidney transplant candidates living in linguistically isolated communities would be less likely to achieve active waitlist status.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We merged Organ Procurement and Transplantation Network/United Network for Organ Sharing data with five-digit zip code socioeconomic data from the 2000 US Census. The cumulative incidence of conversion to active waitlist status, death, and delisting before conversion among 84,783 temporarily inactive adult kidney candidates from 2004 to 2012 was determined using competing risks methods. Competing risks regression was performed to characterize the association between linguistic isolation, incomplete transplantation evaluation, and conversion to active status. A household was determined to be linguistically isolated if all members ≥14 years old speak a non-English language and also, speak English less than very well.

RESULTS

A total of 59,147 candidates (70% of the study population) achieved active status over the study period of 9.8 years. Median follow-up was 110 days (interquartile range, 42-276 days) for activated patients and 815 days (interquartile range, 361-1244 days) for candidates not activated. The cumulative incidence of activation over the study period was 74%, the cumulative incidence of death before conversion was 10%, and the cumulative incidence of delisting was 13%. After adjusting for other relevant covariates, living in a zip code with higher percentages of linguistically isolated households was associated with progressively lower subhazards of activation both in the overall population (reference: <1% linguistically isolated households; 1%-4.9% linguistically isolated: subhazard ratio, 0.89; 95% confidence interval, 0.86 to 0.93; 5%-9.9% linguistically isolated: subhazard ratio, 0.83; 95% confidence interval, 0.80 to 0.87; 10%-19.9% linguistically isolated: subhazard ratio, 0.76; 95% confidence interval, 0.72 to 0.80; and ≥20% linguistically isolated: subhazard ratio, 0.71; 95% confidence interval, 0.67 to 0.76) and among candidates designated temporarily inactive due to an incomplete transplant evaluation.

CONCLUSIONS

Our findings indicate that candidates residing in linguistically isolated communities are less likely to complete candidate evaluations and achieve active waitlist status.

Current state of clinical end-points assessment in transplant: Key points

Solid organ transplantation is the treatment of choice for patients with end-stage organ disease. However, organ transplantation can stress the cardiovascular system and decrease immune surveillance, leading to early mortality and graft loss due to multiple underlying comorbidities. Clinical end-points in transplant include death and graft failure. Thus, generating accurate predictive models through regression models is crucial to test for definitive clinical post-transplantation end-points. Survival predictive models should assemble efficient surrogate markers or prognostic factors to generate a minimal set of variables derived from a proper modeling strategy through regression models. However, a few critical points should be considered when reporting survival analyses and regression models to achieve proper discrimination and calibration of the predictive models. Additionally, population-based risk scores may underestimate risk prediction in transplant. The application of predictive models in these patients should therefore incorporate both classical and non-classical risk factors, as well as community-based health indicators and transplant-specific factors to quantify the outcomes in terms of survival properly. This review focuses on assessment of clinical end-points in transplant through regression models by combining predictive and surrogate variables, and considering key points in these analyses to accurately predict definitive end-points, which could aid clinicians in decision making.

New Solutions to Reduce Discard of Kidneys Donated for Transplantation

Kidney transplantation is a cost-saving treatment that extends the lives of patients with ESRD. Unfortunately, the kidney transplant waiting list has ballooned to over 100,000 Americans. Across large areas of the United States, many kidney transplant candidates spend over 5 years waiting and often die before undergoing transplantation. However, more than 2500 kidneys (>17% of the total recovered from deceased donors) were discarded in 2013, despite evidence that many of these kidneys would provide a survival benefit to wait-listed patients. Transplant leaders have focused attention on transplant center report cards as a likely cause for this discard problem, although that focus is too narrow. In this review, we examine the risks associated with accepting various categories of donated kidneys, including discarded kidneys, compared with the risk of remaining on dialysis. With the goal of improving access to kidney transplant, we describe feasible proposals to increase acceptance of currently discarded organs.

Functional status, time to transplantation, and survival benefit of kidney transplantation among wait-listed candidates

BACKGROUND

In the context of an aging end-stage renal disease population with multiple comorbid conditions, transplantation professionals face challenges in evaluating the global health of patients awaiting kidney transplantation. Functional status might be useful for identifying which patients will derive a survival benefit from transplantation versus dialysis.

STUDY DESIGN

Retrospective cohort study of wait-listed patients using data for functional status from a national dialysis provider linked to United Network for Organ Sharing registry data.

SETTING & PARTICIPANTS

Adult kidney transplantation candidates added to the waiting list between 2000 and 2006.

PREDICTOR

Physical Functioning scale of the Medical Outcomes Study 36-Item Short Form Health Survey, analyzed as a time-varying covariate.

OUTCOMES

Kidney transplantation; survival benefit of transplantation versus remaining wait-listed.

MEASUREMENTS

We used multivariable Cox regression to assess the association between physical function with study outcomes. In survival benefit analyses, transplantation status was modeled as a time-varying covariate.

RESULTS

The cohort comprised 19,242 kidney transplantation candidates (median age, 51 years; 36% black race) receiving maintenance dialysis. Candidates in the lowest baseline Physical Functioning score quartile were more likely to be inactivated (adjusted HR vs highest quartile, 1.30; 95% CI, 1.21-1.39) and less likely to undergo transplantation (adjusted HR vs highest quartile, 0.64; 95% CI, 0.61-0.68). After transplantation, worse Physical Functioning score was associated with shorter 3-year survival (84% vs 92% for the lowest vs highest function quartiles). However, compared to dialysis, transplantation was associated with a statistically significant survival benefit by 9 months for patients in every function quartile.

LIMITATIONS

Functional status is self-reported.

CONCLUSIONS

Even patients with low function appear to live longer with kidney transplantation versus dialysis. For wait-listed patients, global health measures such as functional status may be more useful in counseling patients about the probability of transplantation than in identifying who will derive a survival benefit from it.

Functional status, time to transplantation, and survival benefit of kidney transplantation among wait-listed candidates

BACKGROUND

In the context of an aging end-stage renal disease population with multiple comorbid conditions, transplantation professionals face challenges in evaluating the global health of patients awaiting kidney transplantation. Functional status might be useful for identifying which patients will derive a survival benefit from transplantation versus dialysis.

STUDY DESIGN

Retrospective cohort study of wait-listed patients using data for functional status from a national dialysis provider linked to United Network for Organ Sharing registry data.

SETTING & PARTICIPANTS

Adult kidney transplantation candidates added to the waiting list between 2000 and 2006.

PREDICTOR

Physical Functioning scale of the Medical Outcomes Study 36-Item Short Form Health Survey, analyzed as a time-varying covariate.

OUTCOMES

Kidney transplantation; survival benefit of transplantation versus remaining wait-listed.

MEASUREMENTS

We used multivariable Cox regression to assess the association between physical function with study outcomes. In survival benefit analyses, transplantation status was modeled as a time-varying covariate.

RESULTS

The cohort comprised 19,242 kidney transplantation candidates (median age, 51 years; 36% black race) receiving maintenance dialysis. Candidates in the lowest baseline Physical Functioning score quartile were more likely to be inactivated (adjusted HR vs highest quartile, 1.30; 95% CI, 1.21-1.39) and less likely to undergo transplantation (adjusted HR vs highest quartile, 0.64; 95% CI, 0.61-0.68). After transplantation, worse Physical Functioning score was associated with shorter 3-year survival (84% vs 92% for the lowest vs highest function quartiles). However, compared to dialysis, transplantation was associated with a statistically significant survival benefit by 9 months for patients in every function quartile.

LIMITATIONS

Functional status is self-reported.

CONCLUSIONS

Even patients with low function appear to live longer with kidney transplantation versus dialysis. For wait-listed patients, global health measures such as functional status may be more useful in counseling patients about the probability of transplantation than in identifying who will derive a survival benefit from it.

Attitudes and perceptions of patients on the kidney transplant waiting list toward mobile health-delivered physical activity programs

CONTEXT

Dialysis patients' lifestyles are associated with low levels of physical activity, increasing the chances of being removed from kidney waiting lists or dying while awaiting transplant because of increased cardiovascular risk factors and deteriorating health conditions. Personalized mobile health (mHealth) delivered programs may support their engagement in healthier lifestyles, maintain transplant eligibility, and reduce premature mortality.

OBJECTIVE

To explore barriers and perceptions of physical activity behaviors and gauge interest in using mHealth in a physical activity wellness program for dialysis patients on the kidney transplant waiting list.

PARTICIPANTS AND DESIGN

In-depth key informant interviews were conducted with 22 randomly selected dialysis patients during dialysis treatment in an urban Southeastern coastal city. A theory-guided community-based participatory research approach was used to develop the interview content. Constructivist grounded theory guided the data analysis using NVIVO 10 (QSR Int). The 32-item checklist from the Consolidated Criteria for Reporting Qualitative Studies was used in the qualitative reporting.

RESULTS

Dialysis patients had a mean age of 46 (SD, 10.7) years, 45% were female, and 82% were African American. Their mean duration on transplant waiting lists was 6.7 (SD 4.3) years, and 73% owned smartphones. After saturation was reached, predominant themes included (1) physical activity was perceived as optional, (2) social support both encouraged and limited physical activity, (3) chronic stress and coping influenced physical activity, (4) spirituality provided strength to engage in physical activity, (5) self-care management practices varied considerably, and (6) high interest (95%) for using mHealth to promote physical activity was found. Patients preferred their home and neighborhood environments to intradialytic settings for engaging in physical activity.

Inactivity on the kidney transplant wait-list is associated with inferior pre- and post-transplant outcomes

BACKGROUND

The majority of kidney transplant (KT) candidates spend some time on the transplant wait-list (WL) prior to kidney transplantation. We examined the impact of WL inactivity on clinical outcomes.

METHODS

All adult KT candidates first actively wait-listed between January 1, 1996, and December 31, 2005, in the United States were grouped by frequency of inactivity on the WL. Transplantation rate, pre- and post-transplant patient survival and death-censored kidney graft survival were compared.

RESULTS

Of 159,774 candidates who were placed on the WL, 48,598 (30.4%) experienced one or more periods of inactivity. Candidates with inactivity once or more on the WL had 42% and 27% less likelihood of KT, respectively (HR 0.58, 95% CI 0.57, 0.59 and HR 0.73, 95% CI 0.71, 0.75). WL inactivity once or more was associated with a higher likelihood of death (HR 1.94, 95% CI 1.88, 2.00 and HR 2.13, 95% CI 2.02, 2.24). Among KT recipients, inactivity more than once on the WL was associated with a higher risk of death (HR 1.14, 95% CI 1.05, 1.23).

CONCLUSIONS

Periods of inactivity on the WL predict increased mortality pre- and post-transplantation. A better understanding of the reasons for WL inactivity is essential to improve WL management and post-transplant outcomes.

Organ bioengineering and regeneration as the new Holy Grail for organ transplantation

Organ transplantation is a victim of its own success. In view of the excellent results achieved to date, the demand for organs is escalating whereas the supply has reached a plateau. Consequently, waiting times and mortality on the waiting list are increasing dramatically. Recent achievements in organ bioengineering and regeneration have provided proof of principle that the application of organ bioengineering and regeneration technologies to manufacture organs for transplant purposes may offer the quickest route to clinical application. As investigators are focusing their interest on the utilization and manipulation of autologous cells, ideally the end product will be the equivalent of an autograft such that the recipient will not require any antirejection medication. Achievement of an immunosuppression-free state has been pursued but has proven to be a difficult odyssey since the early days of the transplant era, yet an immediate, stable, durable, and reproducible immunosuppression-free state remains an unfulfilled quest. As organ bioengineering and regeneration has shown the potential to meet both the needs for a new source of organs that may eclipse the increasing organ demand and an immunosuppression-free state, advances in this field could become the new Holy Grail for transplant sciences.

Prominent impact of community risk factors on kidney transplant candidate processes and outcomes

Numerous factors impact patients' health beyond traditional clinical characteristics. We evaluated the association of risk factors in kidney transplant patients' communities with outcomes prior to transplantation. The primary exposure variable was a community risk score (range 0-40) derived from multiple databases and defined by factors including prevalence of comorbidities, access and quality of healthcare, self-reported physical and mental health and socioeconomic status for each U.S. county. We merged data with the Scientific Registry of Transplant Recipients (SRTR) and utilized risk-adjusted models to evaluate effects of community risk for adult candidates listed 2004-2010 (n = 209 198). Patients in highest risk communities were associated with increased mortality (adjusted hazard ratio [AHR] = 1.22, 1.16-1.28), decreased likelihood of living donor transplantation (adjusted odds ratio [AOR] = 0.90, 0.85-0.94), increased waitlist removal for health deterioration (AHR = 1.36, 1.22-1.51), decreased likelihood of preemptive listing (AOR = 0.85, 0.81-0.88), increased likelihood of inactive listing (AOR = 1.49, 1.43-1.55) and increased likelihood of listing for expanded criteria donor kidneys (AHR = 1.19, 1.15-1.24). Associations persisted with adjustment for rural-urban location; furthermore the independent effects of rural-urban location were largely eliminated with adjustment for community risk. Average community risk varied widely by region and transplant center (median = 21, range 5-37). Community risks are powerful factors associated with processes of care and outcomes for transplant candidates and may be important considerations for developing effective interventions and measuring quality of care of transplant centers.

Carbon monoxide inhibits apoptosis during cold storage and protects kidney grafts donated after cardiac death

Ischemia/reperfusion (I/R) injury remains as a serious deleterious factor in kidney transplantation (KTx). We hypothesized that carbon monoxide (CO), an endogenous potent cytoprotective molecule, inhibits hypothermia-induced apoptosis of kidney grafts. Using the rat KTx model mimicking the conditions of donation after cardiac death (DCD) as well as nontransplantable human kidney grafts, this study examined effects of CO in preservation solution in improving the quality of marginal kidney grafts. After cardiac cessation, rat kidneys underwent 40 min warm ischemia (WI) and 24 h cold storage (CS) in control UW or UW containing CO (CO-UW). At the end of CS, kidney grafts in control UW markedly increased mitochondrial porin release into the cytosol and resulted in increased cleaved caspase-3 and PARP expression. In contrast, grafts in CO-UW had significantly reduced mitochondrial breakdown and caspase pathway activation. After KTx, recipient survival significantly improved with CO-UW with less TUNEL(+) cells and reduced mRNA upregulation for proinflammatory mediators (IL-6, TNF-α, iNOS). Furthermore, when nontransplantable human kidney grafts were stored in CO-UW for 24 h, graft PARP expression, TUNEL(+) cells, and proinflammatory mediators were less than those in control UW. CO in UW inhibited hypothermia-induced apoptosis and significantly improved kidney graft function and outcomes of KTx.

Year in review 2009: Critical Care--cardiac arrest, trauma and disasters

During 2009, Critical Care published nine papers on various aspects of resuscitation, prehospital medicine, trauma care and disaster response. One article demonstrated that children as young as 9 years of age can learn cardiopulmonary resuscitation (CPR) effectively, although, depending on their size, some may have difficulty performing it. Another paper showed that while there was a trend toward mild therapeutic hypothermia reducing S-100 levels, there was no statistically significant change. Another predictor study also showed a strong link between acute kidney injury and neurologic outcome while another article described a program in which kidneys were harvested from cardiac arrest patients and showed an 89% graft survival rate. One experimental investigation indicated that when a pump-less interventional lung assist device is present, leaving the device open (unclamped) while performing CPR has no harmful effects on mean arterial pressures and it may have positive effects on blood oxygenation and CO2 clearance. One other study, conducted in the prehospital environment, found that end-tidal CO2 could be useful in diagnosing pulmonary embolism. Three articles addressed disaster medicine, the first of which described a triage system for use during pandemic influenza that demonstrated high reliability in delineating patients with a good chance of survival from those likely to die. The other two studies, both drawn from the 2008 Sichuan earthquake experience, showed success in treating crush injured patients in an on-site tent ICU and, in the second case, how the epidemiology of earthquake injuries and related factors predicted mortality.

Ineligibility for renal transplantation: prevalence, causes and survival in a consecutive cohort of 445 patients

Little is known about the proportion of renal transplant candidates who are considered ineligible by the transplant center, the reasons of their ineligibility and their survival during dialysis. In this retrospective, single-center study of 445 adult patients referred between 2001 and 2006, 36 (8%) were deemed ineligible for medical contraindications. The leading reason was cardiovascular (CV) (75%), specifically aorto-iliac, and/or limb vessels atheromatosis or calcifications; ischemic heart disease; or a combination thereof. Nine patients had other contraindications that were absolute for three of them; six patients displayed a combination of relative contraindications. When compared to eligible patients (N = 409), those ineligible were significantly older (60 yr vs. 48), more often diabetics (50% vs. 15%), obese (39% vs. 17%) suffering from coronary artery disease (53% vs. 11%) and peripheral arterial disease (86% vs. 11%). Their primary nephropathy was more often diabetic and/or hypertensive/nephroangiosclerosis (61% vs. 23%), and their median dialysis vintage prior to evaluation was longer (29 months vs. 10, p < 0.0001). The actuarial survival of ineligible patients was significantly lower than that of eligible patients (at five yr: 53% vs. 88%). Adequate control of CV risk factors before dialysis and early referral for transplantation might help to improve eligibility of renal transplant candidates.

The evolving challenge of evaluating older renal transplant candidates

The demographic factor over age 65 years represents the fastest growing segment of the end-stage kidney disease, wait-listed for kidney transplant, and transplanted populations. As a result, transplant physicians are increasingly asked to evaluate candidacy in older patients. Relatively little attention has been paid to the unique aspects of the pretransplant evaluation in older persons. The natural tendency is to focus on individual comorbidities as isolated entities, such as a history of coronary heart disease, while ignoring factors more specific to the aging process itself. Assessment of the burden of comorbidity along with the application of standardized geriatric assessment tools, such as the measurement of physical and cognitive function, has the potential to refine the pretransplant evaluation process in older kidney transplant candidates.

Geographic variation in end-stage renal disease incidence and access to deceased donor kidney transplantation

The effect of demand for kidney transplantation, measured by end-stage renal disease (ESRD) incidence, on access to transplantation is unknown. Using data from the U.S. Census Bureau, Centers for Medicare & Medicaid Services (CMS) and the Organ Procurement and Transplantation Network/Scientific Registry of Transplant Recipients (OPTN/SRTR) from 2000 to 2008, we performed donation service area (DSA) and patient-level regression analyses to assess the effect of ESRD incidence on access to the kidney waiting list and deceased donor kidney transplantation. In DSAs, ESRD incidence increased with greater density of high ESRD incidence racial groups (African Americans and Native Americans). Wait-list and transplant rates were relatively lower in high ESRD incidence DSAs, but wait-list rates were not drastically affected by ESRD incidence at the patient level. Compared to low ESRD areas, high ESRD areas were associated with lower adjusted transplant rates among all ESRD patients (RR 0.68, 95% CI 0.66-0.70). Patients living in medium and high ESRD areas had lower transplant rates from the waiting list compared to those in low ESRD areas (medium: RR 0.68, 95% CI 0.66-0.69; high: RR 0.63, 95% CI 0.61-0.65). Geographic variation in access to kidney transplant is in part mediated by local ESRD incidence, which has implications for allocation policy development.

Multiple listing in kidney transplantation

The increasing number of patients with end-stage renal disease and the expanding waiting lists for various solid-organ transplants, particularly kidney transplants, has compelled prospective transplant recipients and their care teams to explore novel ways to accelerate this process, initiating the practice of multiple listing. Multiple listing is defined as being listed for an organ transplant at more than 1 transplant center. Current policy allows patients to be listed at more than 1 transplant center in 1 or more organ procurement organization. Multiple listing can be beneficial for different groups of transplant candidates. Current data support a beneficial effect for the patient on multiple waiting lists, most notably portending a survival advantage for transplant recipients. The kidney transplant list has the most patients who are multiply listed (4.7%), followed by the liver transplant list at 3.8%. The main potential downside of multiple listing is its effect on patients not on multiple lists, as well as the cost accrued to achieve multiple listings. With the newly clarified policy of the United Network for Organ Sharing, a pivotal role for nephrologists in educating patients about the option of multiple listing becomes more apparent. In this article, current practices and policies regarding multiple listing are reviewed and opinions and ethics relating to the practice are discussed.

Half of kidney transplant candidates who are older than 60 years now placed on the waiting list will die before receiving a deceased-donor transplant

BACKGROUND AND OBJECTIVES

Waiting times to deceased-donor transplantation (DDTx) have significantly increased in the past decade. This trend particularly affects older candidates given a high mortality rate on dialysis.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We conducted a retrospective analysis from the national Scientific Registry of Transplant Recipients database that included 54,669 candidates who were older than 60 yr and listed in the United States for a solitary kidney transplant from 1995 through 2007. Using survival models, we estimated time to DDTx and mortality after candidate listing with and without patients initially listed as temporarily inactive (status 7).

RESULTS

Almost half (46%) of candidates who were older than 60 yr and listed in 2006 through 2007 are projected to die before receiving a DDTx. This proportion varied by individual characteristics: Diabetes (61%), age > or =70 yr (52%), black (62%), blood types O (60%) and B (71%), highly sensitized (68%), and on dialysis at listing (53%). Marked variation also existed by United Network for Organ Sharing region (6 to 81%). The overall projected proportion was reduced to 35% excluding patients who initially were listed as status 7.

CONCLUSIONS

These data highlight the prominent and growing challenge facing the field of kidney transplantation. Older candidates are now at significant risk for not surviving the interval in which a deceased-donor transplant would become available. Importantly, this risk is variable within this population, and specific information should be disseminated to patients and caregivers to facilitate informed decision-making and potential incentives to seek living donors.