Recipient Age and Risk for Mortality After Kidney Transplantation in England

A competing risks model to estimate the risk of graft failure and patient death after kidney transplantation using continuous donor-recipient age combinations

Graft failure and recipient death with functioning graft are important competing outcomes after kidney transplantation. Risk prediction models typically censor for the competing outcome thereby overestimating the cumulative incidence. The magnitude of this overestimation is not well described in real-world transplant data. This retrospective cohort study analyzed data from the European Collaborative Transplant Study (n = 125 250) and from the American Scientific Registry of Transplant Recipients (n = 190 258). Separate cause-specific hazard models using donor and recipient age as continuous predictors were developed for graft failure and recipient death. The hazard of graft failure increased quadratically with increasing donor age and decreased decaying with increasing recipient age. The hazard of recipient death increased linearly with increasing donor and recipient age. The cumulative incidence overestimation due to competing risk-censoring was largest in high-risk populations for both outcomes (old donors/recipients), sometimes amounting to 8.4 and 18.8 percentage points for graft failure and recipient death, respectively. In our illustrative model for posttransplant risk prediction, the absolute risk of graft failure and death is overestimated when censoring for the competing event, mainly in older donors and recipients. Prediction models for absolute risks should treat graft failure and death as competing events.

Desensitization With Imlifidase for HLA-Incompatible Deceased Donor Kidney Transplantation: A Delphi International Expert Consensus

Highly sensitized (HS) patients in need of kidney transplantation (KTx) typically spend a longer time waiting for compatible kidneys, are unlikely to receive an organ offer, and are at increased risk of antibody-mediated rejection (AMR). Desensitization using imlifidase, which is more rapid and removes total body immunoglobulin G (IgG) to a greater extent than other methods, enables transplantation to occur between HLA-incompatible (HLAi) donor-recipient pairs and allows patients to have greater access to KTx. However, when the project was launched there was limited data and clinical experience with desensitization in general and with imlifidase specifically. Hence, this Delphi methodology was used to reach a consensus from a multi-disciplinary team (MDT) of experts from 15 countries on the management of HS patients undergoing imlifidase HLAi from a deceased donor (DD) KTx. This Delphi consensus provides clinical practice guidance on the use of imlifidase in the end-to-end management of HS patients undergoing an HLAi DD KTx and supports centers in the development of guidelines for the utilization and integration of imlifidase into clinical practice.

Long-Term Results of Kidney Transplantation in Patients Aged 60 Years and Older

Background/Objectives: The results of kidney transplantation (KTx) in elderly patients are deteriorated by more frequent use of organs procured from older or extended criteria donors (ECDs). To eliminate the influence of donor factors on the transplantation results, the pair analysis method was applied. The study aimed to assess the survival, during long-term follow-up after transplantation, of recipients and transplanted kidneys, graft function, and factors influencing survival in recipients aged 60 years and older (≥60) compared to recipients aged less than 60 years (<60) who received a kidney from the same brain death donor (DBD). Methods: The study group consisted of 213 consecutive patients ≥60 who received a kidney procured from a DBD from whom the second procured kidney was transplanted to a patient <60 (control group). Results: The survival rates in the 10-year follow-up period were lower in those recipients ≥60 than in the control group (p < 0.01). The survival rates of the transplanted kidneys were comparable in both groups, while the death-censored graft survival was higher in those patients ≥60 than in the control group (p < 0.05). The estimated glomerular filtration rate levels were similar in the follow-up in patients ≥60 compared to those recipients <60. Transplantation of kidneys procured from ECD, longer duration of dialysis treatment, and longer duration of cold ischemia time (CIT) affected the recipient and graft survival in the ≥60 patients. Death-censored kidney graft survival was influenced by transplantation of a kidney procured from ECD, longer CIT, and the need for reoperation in the early postoperative period. Conclusions: Despite the higher mortality in the kidney recipients ≥60, the long-term results of KTx after the elimination of donor-dependent factors are similar or better compared to the recipients <60. The factors influencing the results of KTx in elderly recipients differ from those observed in the entire cohort and younger patients.

Association between the age-adjusted Charlson Comorbidity Index and complications after kidney transplantation: a retrospective observational cohort study

BACKGROUND

Complications following kidney transplantation elevate the risks of readmission and mortality. The aim of this study was to assess the association between the age-adjusted Charlson Comorbidity Index (ACCI) and postoperative complications among kidney transplant (KT) recipients.

METHODS

Between January 2015 and March 2021, a study involving 886 kidney transplant recipients at the Third Affiliated Hospital of Sun Yat-sen University was conducted. Postoperative complications were defined by the Clavien-Dindo Classification of Surgical Complications. Target Maximum Likelihood Estimation (TMLE) was employed to assess the association between ACCI and postoperative complications. The odds ratio (OR) was computed to determine the relationship between ACCI and postoperative complications. Subsequent interaction and stratified analyses were performed to assess the robustness of the findings.

RESULTS

Out of 859 KT participants ultimately included in the study, 30.7% were documented to have encountered postoperative complications. Participants with an ACCI value exceeding 3 exhibited a notably increased risk of postoperative complications following multivariable adjustment [aOR = 1.64, 95% CI [1.21,2.21], p = 0.001]. Congestive heart failure (OR = 16.18, 95% CI [1.98-132.17], p < 0.001), peripheral vascular disease (OR = 2.32, 95% CI [1.48-3.78], p < 0.001), and chronic obstructive pulmonary disease (OR = 6.05, 95% CI [2.95-12.39], p < 0.001) emerged as the top three preoperative comorbidities significantly linked to postoperative complications in ACCI.

CONCLUSION

An ACCI value exceeding 3 preoperatively constituted a risk factor for postoperative complications among KT patients.

Age-modified risk factors for mortality of non-elderly adult kidney transplant recipients: a retrospective database analysis

PURPOSE

We aimed to investigate the role of the recipient's age strata in modifying the associations between risk factors and mortality in non-elderly adult kidney transplant (KT) recipients (KTR).

METHODS

We stratified 108,695 adult KTRs between 2000 and 2016 with conditional 1-year survival after KT into cohorts based on age at transplant: 18-49 years and 50-64 years. We excluded KTRs aged < 18 years or > / = 65 years. KTRs were observed for 5 years during the 2nd through 6th years post-KT for the outcome, all-cause mortality.

RESULTS

Increasing recipient age strata (18-49-year-old and 50-64-year-old) correlated with decreasing 6-year post-KT survival rates conditional on 1-year survival (79% and 57%, respectively, p < 0.0001). Middle adult age stratum was associated with a higher risk of all-cause mortality than young adult age stratum in KTRs of Hispanic/Latino and other races [HR = 1.23, 95% CI = 1.04-1.45 and HR = 1.51, 95% CI = 1.16-1.97, respectively] and with a primary native renal diagnosis of hypertension or glomerulonephritis [HR = 1.32, 95% CI = 1.12-1.55 and HR = 1.29, 95% CI = 1.10-151, respectively]. When compared with the young adult age stratum, the middle adult age stratum had a mitigating effect on the higher risk of mortality associated with sirolimus-mycophenolate or sirolimus-tacrolimus than the standard calcineurin inhibitor-mycophenolate regimen [HR = 0.75, 95% CI = 0.57-0.99 and HR = 0.71, 95% CI = 0.57-0.89, respectively].

CONCLUSION

Among adult non-elderly KTRs, the age strata, 18-49 years, and 50-64 years, have varying modifying effects on the strength and direction of associations between some specific risk factors and all-cause mortality.

Unraveling complexity: morbidity factors in elderly kidney transplant recipients

Background

The rising prevalence of end-stage renal failure in the elderly has led to an increased number of kidney transplantations in older individuals. While age does not solely determine transplant eligibility, frailty in elderly recipients significantly impacts post-transplant outcomes, particularly within the first year.

Methods

The RETRAITE (REnal TRAnsplantIon ouTcome in Elderly recipients) study, a single-center retrospective cohort study at Grenoble Alpes University Hospital (France), examined kidney transplant recipients aged 70 years and above transplanted between 2015 and 2020. The composite primary endpoint was defined as either of any hospital stay exceeding 40 days, death and/or return to dialysis within the first post-transplant year. The study explored risk factors for recipient and graft survival, rejection, hospitalizations over 40 days, and severe infections during the initial post-transplant year.

Results

Over six years, 149 patients aged 70 years or older received transplants. Eleven patients died, and seven returned to dialysis within the first year, corresponding to a 1-year graft survival rate of 87.9%. At 1 year, 49 patients (33%) met the composite endpoint. There was a significant association between the composite endpoint and curative anticoagulation [odds ratio (OR) 5.20; P < .001], peripheral arteriopathy (OR 3.14; P < .001) and delayed graft function (OR 8.24; P < .001). This cohort then was merged with a cohort of 150 younger kidney transplanted patients and we confirmed these results. Time on dialysis, prolonged cold ischemia and donor age contributed to higher morbidity and mortality. Conversely, preemptive and living donor transplants were associated with lower morbidity and mortality.

Conclusions

In this cohort aged over 70 years, age alone did not statistically correlate with increased morbidity and mortality. Variables related to grafts and donors, especially curative anticoagulation, were linked to poorer outcomes, emphasizing the favorable impact of preemptive and living donor transplants on morbidity and mortality in elderly patients.

Debiased lasso for stratified Cox models with application to the national kidney transplant data

The Scientific Registry of Transplant Recipients (SRTR) system has become a rich resource for understanding the complex mechanisms of graft failure after kidney transplant, a crucial step for allocating organs effectively and implementing appropriate care. As transplant centers that treated patients might strongly confound graft failures, Cox models stratified by centers can eliminate their confounding effects. Also, since recipient age is a proven non-modifiable risk factor, a common practice is to fit models separately by recipient age groups. The moderate sample sizes, relative to the number of covariates, in some age groups may lead to biased maximum stratified partial likelihood estimates and unreliable confidence intervals even when samples still outnumber covariates. To draw reliable inference on a comprehensive list of risk factors measured from both donors and recipients in SRTR, we propose a de-biased lasso approach via quadratic programming for fitting stratified Cox models. We establish asymptotic properties and verify via simulations that our method produces consistent estimates and confidence intervals with nominal coverage probabilities. Accounting for nearly 100 confounders in SRTR, the de-biased method detects that the graft failure hazard nonlinearly increases with donor's age among all recipient age groups, and that organs from older donors more adversely impact the younger recipients. Our method also delineates the associations between graft failure and many risk factors such as recipients' primary diagnoses (e.g. polycystic disease, glomerular disease, and diabetes) and donor-recipient mismatches for human leukocyte antigen loci across recipient age groups. These results may inform the refinement of donor-recipient matching criteria for stakeholders.

The Long-Term Outcome of Kidney Transplant Recipients in the Eighth Decade Compared With Recipients in the Seventh Decade of Life

BACKGROUND

With the aging of the population, more older patients are being considered for kidney transplantation; therefore, it is crucial to evaluate the risks and benefits of transplantation in this population. This study aimed to assess long-term outcomes of kidney transplantation in a cohort of patients who underwent kidney transplantation at age >70 years, compared with patients aged 60 to 69 years at transplantation.

METHODS

Included in the study were 261 consecutive kidney transplant recipients: 52 were aged >70 years, and 209 were aged 60 to 69 years at transplantation. Data were collected retrospectively and analyzed using multivariate logistic regression to identify potential outcome risk factors.

RESULTS

The number of transplants in both groups increased during the study period. Mortality after transplantation was strongly correlated to age (hazard ratio [HR] = 1.11; 95% CI, 1.05-1.18; P < .001), deceased donor (HR = 2.0; 95% CI, 1.1-3.8; P = .034), and pretransplant diabetes (HR = 2.9; 95% CI, 1.7-4.9; P = .001). Recipients aged >70 years had an increased risk of death censored graft failure (HR = 2.98; 95% CI, 1.56-5.74; P = .001). In living donor transplants, 3-year survival was 80% in recipients age >70 years, compared with 98% in the 60- to 69-year group. Five-year survival was 71% and 92%, respectively. In deceased donor transplants, 3-year survival was 63% and 78%, and 5-year survival was 58% and 72%, respectively. The risk of malignancy (excluding nonmelanotic skin cancer) was nearly triple in the age >70 years group (HR = 2.96; 95% CI, 1.3-6.8; P = .01).

CONCLUSIONS

Patient and graft survival in kidney recipients in the eighth decade is worse compared with recipients in the seventh decade of life. However, it is improved with living kidney donation.

Lowering maintenance immune suppression in elderly kidney transplant recipients; connecting the immunological and clinical dots

The management of long-term immune suppressive medication in kidney transplant recipients is a poorly explored field in the area of transplant medicine. In particular, older recipients are at an increased risk for side effects and have an exponentially increased risk of infection-related death. In contrast, an aged immune system decreases the risk of acute T-cell-mediated rejection in older recipients. Recent advances in alloimmunity research have shown a rapid and substantial decline in polyfunctional, high-risk CD4⁺ T cells post-transplantation. This lowers the direct alloreactivity responsible for T-cell-mediated rejection, also known as donor-specific hyporesponsiveness. Chronic antibody-mediated rejection (c-aABMR) is the most frequent cause of kidney graft loss in the long term. However, in older adults, c-aABMR as a cause of graft loss is outnumbered by death with a functioning graft. In addition, DSA development and a diagnosis of c-aABMR plateau ~10 years after transplantation, resulting in a very low risk for rejection thereafter. The intensity of immune suppression regimes could likely be reduced accordingly, but trials in this area are scarce. Tacrolimus monotherapy for 1 year after transplantation seems feasible in older kidney transplant recipients with standard immunological risk, showing the expected benefits of fewer infections and better vaccination responses.

Physiological Age by Artificial Intelligence-Enhanced Electrocardiograms as a Novel Risk Factor of Mortality in Kidney Transplant Candidates

BACKGROUND

Mortality risk assessment before kidney transplantation (KT) is imperfect. An emerging risk factor for death in nontransplant populations is physiological age as determined by the application of artificial intelligence to the electrocardiogram (ECG). The aim of this study was to examine the relationship between ECG age and KT waitlist mortality.

METHODS

We applied a previously developed convolutional neural network to the ECGs of KT candidates evaluated 2014 to 2019 to determine ECG age. We used a Cox proportional hazard model to examine whether ECG age was associated with waitlist mortality.

RESULTS

Of the 2183 patients evaluated, 59.1% were male, 81.4% were white, and 11.4% died during follow-up. Mean ECG age was 59.0 ± 12.0 y and mean chronological age at ECG was 53.3 ± 13.6 y. After adjusting for chronological age, comorbidities, and other characteristics associated with mortality, each increase in ECG age of >10 y than the average ECG age for patients of a similar chronological age was associated with an increase in mortality risk (hazard ratio 3.59 per 10-y increase; 95% confidence interval, 2.06-5.72; P  < 0.0001).

CONCLUSIONS

ECG age is a risk factor for KT waitlist mortality. Determining ECG age through artificial intelligence may help guide risk-benefit assessment when evaluating candidates for KT.

Renal Transplantation in the Elderly: Are They All the Same? A Multicenter, Comorbidity-Based Study

INTRODUCTION

The age for kidney transplantation (KT) is no longer a limitation and several studies have shown benefits in the survival of elderly patients. The aim of this study was to examine the relationship of the baseline Charlson comorbidity index (CCI) score to morbidity and mortality after transplantation.

METHODS

In this multicentric observational retrospective cohort study, we included patients older than 60 years admitted on the waiting list (WL) for deceased donor KT from January 01, 2006, to December 31, 2016. The CCI score was calculated for each patient at inclusion on the WL.

RESULTS

Data for analysis were available of 387 patients. The patients were divided in tertiles of CCI: group 1 (CCI: 1-2) n = 117, group 2 (CCI: 3-4) n = 158, and group 3 (CCI: ≥5) n = 112. Patient survival was significantly different between CCI groups at 1, 3, and 5 years, respectively: 90%, 88%, and 84% for group 1, 88%, 80%, and 72% for group 2, and 87%, 75%, and 63% for group 3 (p < 0.0001). Variables associated with mortality were CCI score (p < 0.0001), HLA mismatch (p = 0.014), length of hospital stay (p < 0.0001), surgical complications (p = 0.048).

CONCLUSION

Individualized strategies to modify these variables may improve patient's morbidity and mortality after KT.

Sickness Symptoms in Kidney Transplant Recipients: A Scoping Review

Sickness symptoms (depressive symptoms, anxiety, and fatigue) are common among people with chronic illness, often presenting as a symptom cluster. Sickness symptoms persist in many patients with chronic kidney disease, even after kidney transplantation (KT); however, little is known about sickness symptom-induced burden in KT recipients. This scoping review synthesizes available evidence for sickness symptoms in KT recipients, including findings on symptom prevalence, predictors, outcomes, interrelationships, and clustering. Among 38 reviewed studies, none identified sickness symptoms as a cluster, but we observed interrelationships among the symptoms examined. Fatigue was the most prevalent sickness symptom, followed by anxiety and depressive symptoms. Predictors of these symptoms included demographic, clinical, and psychosocial factors, and health-related quality of life was the most researched outcome. Future research should use common data elements to phenotype sickness symptoms, include biological markers, and employ sophisticated statistical methods to identify potential clustering of sickness symptoms in KT recipients.

A cost-effectiveness analysis of patiromer in the UK: evaluation of hyperkalaemia treatment and lifelong RAASi maintenance in chronic kidney disease patients with and without heart failure

BACKGROUND

Chronic kidney disease (CKD) patients with and without heart failure (HF) often present with hyperkalaemia (HK) leading to increased risk of hospitalisations, cardiovascular related events and cardiovascular-related mortality. Renin-angiotensin-aldosterone system inhibitor (RAASi) therapy, the mainstay treatment in CKD management, provides significant cardiovascular and renal protection. Nevertheless, its use in the clinic is often suboptimal and treatment is frequently discontinued due to its association with HK. We evaluated the cost-effectiveness of patiromer, a treatment known to reduce potassium levels and increase cardiorenal protection in patients receiving RAASi, in the UK healthcare setting.

METHODS

A Markov cohort model was generated to assess the pharmacoeconomic impact of patiromer treatment in regulating HK in patients with advanced CKD with and without HF. The model was generated to predict the natural history of both CKD and HF and quantify the costs and clinical benefits associated with the use of patiromer for HK management from a healthcare payer's perspective in the UK.

RESULTS

Economic evaluation of patiromer use compared to standard of care (SoC) resulted in increased discounted life years (8.93 versus 8.67) and increased discounted quality-adjusted life years (QALYs) (6.36 versus 6.16). Furthermore, patiromer use resulted in incremental discounted cost of £2,973 per patient and an incremental cost-effectiveness ratio (ICER) of £14,816 per QALY gained. On average, patients remained on patiromer therapy for 7.7 months, and treatment associated with a decrease in overall clinical event incidence and delayed CKD progression. Compared to SoC, patiromer use resulted in 218 fewer HK events per 1,000 patients, when evaluating potassium levels at the 5.5-6 mmol/l; 165 fewer RAASi discontinuation episodes; and 64 fewer RAASi down-titration episodes. In the UK, patiromer treatment was predicted to have a 94.5% and 100% chance of cost-effectiveness at willingness-to-pay thresholds (WTP) of £20,000/QALY and £30,000/QALY, respectively.

CONCLUSION

This study highlights the value of both HK normalisation and RAASi maintenance in CKD patients with and without HF. Results support the guidelines which recommend HK treatment, e.g., patiromer, as a strategy to enable the continuation of RAASi therapy and improve clinical outcomes in CKD patients with and without HF.

Cardiorespiratory Optimisation By Arteriovenous fistula Ligation after renal Transplantation (COBALT): study protocol for a multicentre randomised interventional feasibility trial

INTRODUCTION

Cardiovascular events are a major cause of mortality following successful kidney transplantation.Arteriovenous fistulas (AVFs) are considered the best option for haemodialysis, but may contribute to this excess mortality because they promote adverse cardiac remodelling and ventricular hypertrophy. This raises the question whether recipients with a well-functioning kidney transplant should undergo elective AVF ligation.

METHODS AND ANALYSIS

The COBALT feasibility study is a multicentre interventional randomised controlled trial (RCT) that will randomise renal transplant patients with stable graft function and a working AVF on a 1:1 basis to standard care (continued conservative management) or to AVF ligation. All patients will perform cardiopulmonary exercise testing (CPET) on recruitment and 6 months later. Daily functioning and quality of life will be additionally assessed by questionnaire completion and objective measure of physical activity. The primary outcome-the proportion of approached patients who complete the study (incorporating rates of consent, receipt of allocated intervention and completion of both CPETs without withdrawal)-will determine progression to a full-scale RCT. Design of the proposed RCT will be informed by an embedded qualitative assessment of participant and healthcare professional involvement.

ETHICS AND DISSEMINATION

This study has been approved by the East Midlands-Derby Research Ethics Committee (22/EM/0002) and the Health Research Authority. The results of this work will be disseminated academically through presentation at national and international renal meetings and via open access, peer-reviewed outputs. Existing networks of renal patient groups will also be used to disseminate the study findings to other key stakeholders.

TRIAL REGISTRATION NUMBER

ISRCTN49033491.

Evolving Trends in Risk Profiles and Outcomes in Older Adults Undergoing Kidney Retransplantation

BACKGROUND

In older adults (≥65), access to and outcomes following kidney transplantation (KT) have improved over the past 3 decades. It is unknown if there were parallel trends in re-KT. We characterized the trends, changing landscape, and outcomes of re-KT in older adults.

METHODS

Among the 44,149 older kidney-only recipients (1995-2016) in the Scientific Registry of Transplant Recipients, we identified 1743 who underwent re-KT. We analyzed trends and outcomes (mortality, death-censored graft failure [DCGF]) by eras (1995-2002, 2003-2014, and 2015-2016) that were defined by changes to the expanded criteria donors and Kidney Donor Profile Index policies.

RESULTS

Among all older kidney-only recipients during 1995-2002, 2003-2014, 2015-2016 the proportion that were re-KTs increased from 2.7% to 4.2% to 5.7%, P < 0.001, respectively. Median age at re-KT (67-68-68, P = 0.04), years on dialysis after graft failure (1.4-1.5-2.2, P = 0.003), donor age (40.0-43.0-43.5, P = 0.04), proportion with panel reactive antibody 80-100 (22.0%-32.7%-48.7%, P < 0.001), and donation after circulatory death (1.1%-13.4%-19.5%, P < 0.001) have increased. Despite this, the 3-y cumulative incidence for mortality (22.3%-19.1%-11.5%, P = 0.002) and DCGF (13.3%-10.0%-5.1%, P = 0.01) decreased over time. Compared with deceased donor retransplant recipients during 1995-2002, those during 2003-2014 and 2015-2016 had lower mortality hazard (aHR = 0.78, 95% confidence interval, 0.63-0.86 and aHR = 0.55, 95% confidence interval, 0.35-0.86, respectively). These declines were noted but not significant for DCGF and in living donor re-KTs.

CONCLUSIONS

In older retransplant recipients, outcomes have improved significantly over time despite higher risk profiles; yet they represent a fraction of the KTs performed. Our results support increasing access to re-KT in older adults; however, approaches to guide the selection and management in those with graft failure need to be explored.

Influence of Calcineurin Inhibitor Choice on Outcomes in Kidney Transplant Recipients Aged ≥60 Y: A Collaborative Transplant Study Report

BACKGROUND

Patients aged ≥60 y represent the fastest growing population among kidney transplant recipients and waitlist patients. They show an elevated infection risk and are frequently transplanted with multiple human leukocyte antigen mismatches. Whether the choice of calcineurin inhibitor influences graft survival, mortality, or key secondary outcomes such as infections in this vulnerable recipient population is unknown.

METHODS

A total of 31 177 kidney transplants from deceased donors performed between 2000 and 2019 at European centers and reported to the Collaborative Transplant Study were analyzed using multivariable Cox and logistic regression analyses. All recipients were ≥60 y old and received tacrolimus (Tac) or cyclosporine A on an intention-to-treat basis, combined with mycophenolic acid or azathioprine plus/minus steroids.

RESULTS

The risk of 3-y death-censored graft loss and patient mortality did not differ significantly between Tac- and cyclosporine A-treated patients (hazard ratio 0.98 and 0.95, P = 0.74 and 0.20, respectively). No difference was found in the overall risk of hospitalization for infection (hazard ratio = 0.95, P = 0.19); however, a lower incidence of rejection treatment (hazard ratio = 0.81, P < 0.001) was observed in Tac-treated patients. Assessment of pathogen-specific hospitalizations revealed no difference in the risk of hospitalization due to bacterial infection (odds ratio = 1.00, P = 0.96), but a significantly higher risk of hospitalization due to human polyomavirus infection was found among Tac-treated patients (odds ratio = 2.45, P = 0.002). The incidence of de novo diabetes was higher for Tac-based immunosuppression (odds ratio = 1.79, P < 0.001).

CONCLUSIONS

Calcineurin inhibitor selection has no significant influence on death-censored graft survival, mortality, and overall infection risk in ≥60-y-old kidney transplant recipients.

Graft and Patient Survival in Kidney Transplant Recipients Over the Age of Sıxty-Five

Introduction: Elderly patients have increased morbidity and mortality compared to younger patients due to existing comorbid diseases and chronic immunosuppression. Therefore, the option of kidney transplantation for renal replacement therapy in elderly patients is still being controversial. Our aim in this study was to evaluate graft function, graft and patient survival, and associated factors in kidney transplant recipients over 65 years of age, at 11 years of follow-up.

Methods: The study included 53 patients aged 65-76 years, out of a total of 1319 patients who underwent live kidney transplantation in the Organ Transplant Center of Acibadem International Hospital between October 2010 and July 2021. Demographic characteristics and creatinine values were recorded. Graft survival rates and patient survival rates at one, three, and five years were analyzed.

Results: Fifty-three patients, 14 female, 39 male, aged 65-76 years were included in the study. The follow-up period of the patients was 7-125 months. During the follow-up, 20 patients died. Graft loss occurred in two of 20 patients who died, and 18 patients died with working grafts. Graft loss developed in two of the 33 surviving patients. In the whole group, one-, three-, and five-year patient survival rates were 94%, 81%, and 76%, respectively.

Conclusion: These results emphasize that kidney transplantation is a viable treatment option in elderly patients who have been well evaluated before kidney transplantation.

Sequential Organ Failure Assessment (SOFA) and 90-day mortality in patients with kidney transplant status at first ICU admission: a cohort study of 428 patients

PURPOSE

We investigated the prognostic accuracy of scores of SOFA for 90-day mortality in patients with kidney transplant status identified from the public Medical Information Mart for Intensive Care III databank.

METHODS

A total of 428 participants with kidney transplant status who were admitted for the first time to the ICU were included. The target-independent and target-dependent variables were the SOFA scores in the first 3 days of ICU admission and 90-day mortality, respectively.

RESULTS

Fully adjusted binary logistic regression indicated that the day-2 and day-3 SOFA scores were positively associated with a risk of 90-day mortality after adjustment for confounders (odds ratio: 1.196, 95% confidence interval: 1.052-1.360; odds ratio: 1.233, 95% confidence interval: 1.062-1.432). The receiver operating characteristic curve showed areas under the curve for the prediction of 90-day mortality from SOFA scores on days 1, 2 and 3 were 0.524, 0.654, and 0.727, respectively. Further analysis using Kaplan-Meier survival curves and multivariate regression models of 90-day survival showed that patients with low SOFA scores survived longer than those with high scores.

CONCLUSION

The SOFA scores in the early days of ICU admission were positively associated with 90-day outcomes although the first-day score showed no significant correlation.

Evaluation of rejection, infection, and malignancy outcomes in elderly liver transplant recipients receiving a similar level of immunosuppression compared to a younger group

Elderly liver transplant (LTx) recipients at a lower risk of acute rejection compared to younger recipients due to immunosenescence. As such, they may benefit from reduced immunosuppression (IS) to minimize infectious and malignant complications. We aimed to evaluate outcomes in LTx recipients ≥60 years compared to a younger group of LTx recipients aged 18-59 years maintained on a similar level of IS. This was a single-center retrospective evaluation of adult LTx recipients from 2013 to 2018 who received methylprednisolone induction and were maintained on tacrolimus, mycophenolate mofetil (MMF), and a prednisone taper. A total of 143 LTx recipients were evaluated. Mean age in the older group was 65 ± 3.8 compared to 49 ± 10.4 years in the younger group (p < 0.0001). Mean tacrolimus levels and the duration of MMF and steroids were comparable. Both groups had a similar incidence of first rejection within 1 year (19.2% in the elderly group vs. 23.1% in the younger group, p = 0.57). There were no statistical difference in terms of infection, malignancy, or patient survival. In conclusion, our data suggests that elderly LTx recipients, when treated with a similar level of IS, had similar 1 year incidence of rejection, infection, malignancy, and patient survival as younger LTx recipients.

Practice Patterns in the Acceptance of Medically Complex Living Kidney Donors with Obesity, Hypertension, Family History of Kidney Disease, or Donor-Recipient Age Discrepancy

Background  To assess the practice patterns of the acceptance of medically complex living kidney donors (MCLKDs). Methods  We distributed a survey to nephrologists and transplant surgeons (TS) across the world through major international transplant societies. The survey contained questions regarding obesity, abnormal blood glucose profile, mild hypertension, donor-recipient age discrepancy, or family history of kidney disease of unknown etiology. Results  In total, 239 respondents from 29 countries (42% were nephrologists and 58% were TS). Most respondents would allow donations from obese donors, especially if they intended to lose weight but would be cautious if these donors had abnormal blood glucose or family history of diabetes mellitus. In hypertensive donors, future pregnancy plans mattered in decisions regarding the acceptance of female donors. Most respondents would allow young donors but would be more cautious if they had a future risk of hypertension or a family history of kidney disease of unknown etiology. They would also allow donations from an older person if prolonged waiting time was anticipated. We found multiple areas of consensus of practice among the diverse members of international transplant societies, with some interesting variations among nephrologists and TS. Conclusions  This survey highlights the practice patterns of the acceptance of MCLKDs among the international community. In the absence of clear guidelines, this survey provides additional information to counsel kidney donors with these conditions.

Immunosuppression Regimen Use and Outcomes in Older and Younger Adult Kidney Transplant Recipients: A National Registry Analysis

BACKGROUND

Although the population of older transplant recipients has increased dramatically, there are limited data describing the impact of immunosuppression regimen choice on outcomes in this recipient group.

METHODS

National data for US Medicare-insured adult kidney recipients (N = 67 362; 2005-2016) were examined to determine early immunosuppression regimen and associations with acute rejection, death-censored graft failure, and mortality using multivariable regression analysis in younger (18-64 y) and older (>65 y) adults.

RESULTS

The use of antithymocyte globulin (TMG) or alemtuzumab (ALEM) induction with triple maintenance immunosuppression (reference) was less common in older compared with younger (36.9% versus 47.0%) recipients, as was TMG/ALEM + steroid avoidance (19.2% versus 20.1%) and mammalian target of rapamycin inhibitor (mTORi)-based (6.7% versus 7.7%) treatments. Conversely, older patients were more likely to receive interleukin (IL)-2-receptor antibody (IL2rAb) + triple maintenance (21.1% versus 14.7%), IL2rAb + steroid avoidance (4.1% versus 1.8%), and cyclosporine-based (8.3% versus 6.6%) immunosuppression. Compared with older recipients treated with TMG/ALEM + triple maintenance (reference regimen), those managed with TMG/ALEM + steroid avoidance (adjusted odds ratio [aOR], 0.440.520.61) and IL2rAb + steroid avoidance (aOR, 0.390.550.79) had lower risk of acute rejection. Older patients experienced more death-censored graft failure when managed with Tac + antimetabolite avoidance (adjusted hazard [aHR], 1.411.782.25), mTORi-based (aHR, 1.702.142.71), and cyclosporine-based (aHR, 1.411.782.25) regimens, versus the reference regimen. mTORi-based and cyclosporine-based regimens were associated with increased mortality in both older and younger patients.

CONCLUSIONS

Lower-intensity immunosuppression regimens (eg, steroid-sparing) appear beneficial for older kidney transplant recipients, while mTORi and cyclosporine-based maintenance immunosuppression are associated with higher risk of adverse outcomes.

Peripheral Vascular Disease and Kidney Transplant Outcomes: Rethinking an Important Ongoing Complication

Peripheral vascular disease (PVD) is highly prevalent in patients on the waiting list for kidney transplantation (KT) and after transplantation and is associated with impaired transplant outcomes. Multiple traditional and nontraditional risk factors, as well as uremia- and transplant-related factors, affect 2 processes that can coexist, atherosclerosis and arteriosclerosis, leading to PVD. Some pathogenic mechanisms, such as inflammation-related endothelial dysfunction, mineral metabolism disorders, lipid alterations, or diabetic status, may contribute to the development and progression of PVD. Early detection of PVD before and after KT, better understanding of the mechanisms of vascular damage, and application of suitable therapeutic approaches could all minimize the impact of PVD on transplant outcomes. This review focuses on the following issues: (1) definition, epidemiological data, diagnosis, risk factors, and pathogenic mechanisms in KT candidates and recipients; (2) adverse clinical consequences and outcomes; and (3) classical and new therapeutic approaches.

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.

Cost-effectiveness and value of information analysis of multiple frequency bioimpedance devices for fluid management in people with chronic kidney disease having dialysis

Background

Among people with chronic kidney disease (CKD) on dialysis, sub-optimal fluid management has been linked with hospitalisation, cardiovascular complications and death. This study assessed the cost-effectiveness using multiple-frequency bioimpedance guided fluid management versus standard fluid management based on clinical judgment.

Methods

A Markov model was developed to compare expected costs, outcomes and quality adjusted life years of the alternative management strategies. The relative effectiveness of the bioimpedance guided approach was informed by a systematic review of clinical trials, and focussed reviews were conducted to identify baseline event rates, costs and health state utility values for application in the model. The model was analysed probabilistically and a value of information (VOI) analysis was conducted to inform the value of conducting further research to reduce current uncertainties in the evidence base.

Results

For the base-case analysis, the incremental cost-effectiveness ratio (ICER) for bioimpedance guided fluid management versus standard management was £16,536 per QALY gained. There was a 59% chance of the ICER being below £20,000 per QALY. Form the VOI analysis, the theoretical upper bound on the value of further research was £53 million. The value of further research was highest for parameters relating to the relative effectiveness of bioimpedance guided management on final health outcomes.

Conclusions

Multiple frequency bioimpedance testing may offer a cost-effective approach to improve fluid management in patients with CKD on dialysis, but further research would be of value to reduce the current uncertainties.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12962-021-00276-6.

Pharmacokinetic and Pharmacodynamic Considerations in Relation to Calcineurin Usage in Elderly Kidney Transplant Recipients

This review summarizes how possible age-related changes in tacrolimus and cyclosporine pharmacokinetics and pharmacodynamics may influence drug dosing and monitoring in the elderly, and highlights how micro-sampling may be useful in this cohort in the future. Advancing biological age leads to physiological changes that can affect drug absorption, distribution, metabolism and excretion, as well as immune system responsiveness. Some studies have shown that elderly recipients may have higher dose-adjusted exposure and/or lower clearance of the calcineurin inhibitors, suggesting that doses may need to be lowered in elderly recipients. Only one study has examined how aging effects drug target enzyme activity and demonstrated that age does not correlate with the calcineurin inhibitor half-maximal inhibitory concentration. Several studies have shown elderly kidney transplant recipients have increased risk of both morbidity and mortality, compared to younger adults due to increased susceptibility to immunosuppressant side effects, particularly cardiovascular disease, infection and malignancy. Current immunosuppressant dosing and monitoring protocols often make no adjustments for age. Lower maintenance immunosuppressant targets in elderly recipients may decrease patient susceptibility to drug side effects, however, further studies are required and appropriate targets need to be established. Blood draw by micro-sampling may be useful for drug monitoring in this cohort in the future, as blood collection is minimally invasive and less painful than venepuncture. Micro-sampling could also make further pharmacokinetic, pharmacodynamics and outcome studies in the elderly more feasible.

[Kidney transplantation in the elderly: A benefit for all patients?]

Age per se should not be a contraindication to kidney transplantation. The first studies have shown a benefit for the survival of elderly eligible patients getting a kidney transplant compared to be maintained on the waiting list. However, more recent data suggest that this benefit is not as constant, notably with a significant early mortality period. The eligibility of elderly patients for transplantation must be based on the usual consideration of co-morbidities, but should also include, for some patients, a geriatric evaluation to detect clinical symptoms of frailty. The decision to transplant an elderly recipient must also integrate the characteristics of the donors, since the use of donors with increasingly expanding criteria can have a negative impact on the survival of these patients.

KDIGO Clinical Practice Guideline on the Evaluation and Management of Candidates for Kidney Transplantation

The 2020 Kidney Disease: Improving Global Outcomes (KDIGO) Clinical Practice Guideline on the Evaluation and Management of Candidates for Kidney Transplantation is intended to assist health care professionals worldwide who evaluate and manage potential candidates for deceased or living donor kidney transplantation. This guideline addresses general candidacy issues such as access to transplantation, patient demographic and health status factors, and immunological and psychosocial assessment. The roles of various risk factors and comorbid conditions governing an individual's suitability for transplantation such as adherence, tobacco use, diabetes, obesity, perioperative issues, causes of kidney failure, infections, malignancy, pulmonary disease, cardiac and peripheral arterial disease, neurologic disease, gastrointestinal and liver disease, hematologic disease, and bone and mineral disorder are also addressed. This guideline provides recommendations for evaluation of individual aspects of a candidate's profile such that each risk factor and comorbidity are considered separately. The goal is to assist the clinical team to assimilate all data relevant to an individual, consider this within their local health context, and make an overall judgment on candidacy for transplantation. The guideline development process followed the Grades of Recommendation Assessment, Development, and Evaluation (GRADE) approach. Guideline recommendations are primarily based on systematic reviews of relevant studies and our assessment of the quality of that evidence, and the strengths of recommendations are provided. Limitations of the evidence are discussed with differences from previous guidelines noted and suggestions for future research are also provided.

CTLA4-Ig prolongs graft survival specifically in young but not old mice

Elderly organ transplant recipients have remained underrepresented in clinical trials, despite representing a rapidly growing population. Here, we assessed age-specific effects of CTLA4-Ig (cytotoxic T-lymphocyte antigen 4-Ig), a fusion protein blocking costimulatory signaling between antigen-presenting cells and T cells through CD28. Cardiac allografts in young mice (2-3 months) treated with CTLA4-Ig survived indefinitely, whereas 80% of old recipients (18 months) had lost their graft after 100 days. CTLA4-Ig was also significantly less effective in older recipients of skin transplants. CTLA4-Ig reduced CD4⁺ central memory and effector memory T cells and diminished systemic interferon-gamma levels only in young recipients. These differences corresponded to a reduced expression of CD28 on antigen-experienced CD4⁺ T cells in old mice. In support, adoptive transfer of old CD4⁺ T cells that were transfected with a lentiviral vector inducing constant expression of CD28 accelerated the rejection of allogeneic skin grafts in young RAG2^-/- recipient mice. Regulatory T cells (Tregs), in contrast, demonstrated an increased expression of CD28 with aging and CTLA4-Ig treatment in old recipients resulted in reduced frequencies, compromised proliferation, and diminished suppressive capacity of Tregs. These findings may prove to have unique clinical consequences for immunosuppression in the growing population of elderly transplant recipients.

Factors Influencing Long-Term Patient and Allograft Outcomes in Elderly Kidney Transplant Recipients

Introduction

Individuals aged ≥65 years are increasingly prevalent on the waitlist for kidney transplantation, yet evidence on recipient and donor factors that define optimal outcomes in elderly patients after kidney transplantation is scarce.

Methods

We used multivariable Cox regression modeling to determine the factors associated with all-cause death, death with a functioning graft, and overall and death-censored graft survival, using data from the Australia and New Zealand Dialysis and Transplant (ANZDATA) registry.

Results

A total of 802 kidney transplant recipients aged ≥65 years underwent their first transplantation between June 2006 and December 2016. Median age at transplantation was 68 years (interquartile range = 66−69 years). The 1-year and 5-year overall patient and graft survivals (95% confidence interval [CI]) were 95.1 (93.5−96.7) and 79.0 (75.1−82.9), and 92.9 (91.1−94.7) and 75.4 (71.3−79.5), respectively. Factors associated with higher risks of all-cause death included prevalent coronary artery disease (adjusted hazard ratio [95% confidence interval] = 1.47 [1.03–2.11]), cerebrovascular disease (1.99 [1.26–3.16]), increasing graft ischemic time (1.06 per hour [1.03–1.09]), donor age (1.02 per year [1.01–1.03]), delayed graft function (1.64 [1.13−2.39]), and peritoneal dialysis pretransplantation (1.71 [1.17–2.51]).

Conclusion

Prevalent vascular disease and peritoneal dialysis as a pretransplantation dialysis modality are risk factors associated with poorer outcomes in transplant recipients aged ≥65 years. Careful selection and evaluation of potential candidates may improve graft and patient outcomes in older patients.

African American polycystic kidney patients receive higher risk kidneys, but do not face increased risk for graft failure or post-transplant mortality

African Americans (AA) are disproportionately affected by end-stage renal disease (ESRD) and have worse outcomes following renal transplantation. Autosomal dominant polycystic kidney disease (ADPKD) is the most common genetic condition leading to ESRD necessitating transplant. We explored this population with respect to race by conducting a retrospective analysis of the UNOS database between 2005 and 2019. Our study included 10,842 (AA n = 1661; non-AA n = 9181) transplant recipients whose primary diagnosis was ADPKD. We further stratified the AA ADPKD population with respect to blood groups (AA blood type B n = 295 vs AA non-B blood type n = 1366), and also compared this cohort to AAs with a diagnosis of DM (n = 16,706) to identify unique trends in the ADPKD population. We analyzed recipient and donor characteristics, generated survival curves, and conducted multivariate analyses. African American ADPKD patients waited longer for transplants (924 days vs 747 days P < .001), and were more likely to be on dialysis (76% vs 62%; p < .001). This same group was also more likely to have AA donors (21% vs 9%; p < .001) and marginally higher KDPI kidneys (0.48 vs 0.45; p < .001). AA race was a risk factor for delayed graft function (DGF), increasing the chance of DGF by 45% (OR 1.45 95% CI 1.26-1.67; p < .001). AA race was not associated with graft failure (HR 1.10 95% CI 0.95-1.28; p = .21) or patient mortality (HR 0.84 95% CI 0.69-1.03; p = .09). Racial disparities exist in the ADPKD population. They should be continually studied and addressed to improve transplant equity.

Comparison of kidney allograft survival in the Eurotransplant senior program after changing the allocation criteria in 2010-A single center experience

Aims

The European Senior Program (ESP) aims to avoid waiting list competition between younger and elderly patients applying for renal transplantation. By listing patients ≥65 years on a separate waiting list and locally allocating of grafts ≥65 years exclusively to this cohort, waiting and cold ischemia times are predicted to be shortened, potentially resulting in improved kidney transplantation outcomes. This study compared a historic cohort of renal transplant recipients being simultaneously listed on the general and the ESP waiting lists with a collective exclusively listed on the ESP list in terms of surrogates of the transplantation outcome.

Methods

Total 151 eligible patients ≥ 65 years from Münster transplant Center, Germany, between 1999 and 2014 were included. Graft function, graft and patient survival were compared using surrogate markers of short- and long-term graft function. Patients were grouped according to their time of transplantation.

Results

Recipients and donors in the newESP (nESP) cohort were significantly older (69.6 ± 3.5 years vs 67.1 ± 2 years, p<0.05; 72.0 ± 5.0 years vs 70.3 ± 5.0 years, p = 0.039), had significantly shorter dialysis vintage (19.6 ± 21.7 months vs 60.2 ± 28.1 months, p<0.001) and suffered from significantly more comorbidities (2.2 ± 0.9 vs 1.8 ± 0.8, p = 0.009) than the historic cohort (HC). Five-year death-censored graft survival was better than in the HC, but 5-year graft and patient survival were better in the ESP cohort. After 2005, cold ischemia time between groups was comparable. nESP grafts showed more primary function and significantly better long-term graft function 18 months after transplantation and onwards.

Conclusion

nESP recipients received significantly older grafts, but experienced significantly shorter time on dialysis. Cold ischemia times were comparable, but graft function in the nESP cohort was significantly better in the long term.

Risk factors for death in kidney transplant patients: analysis from a large protocol biopsy registry

BACKGROUND

Identification and quantification of the relevant factors for death can improve patients' individual risk assessment and decision-making. We used a well-documented patient cohort (n = 892) in a renal transplant programme with protocol biopsies to establish multivariable Cox models for risk assessment at 3 and 12 months post-transplantation.

METHODS

Patients transplanted between 2000 and 2007 were observed up to 11 years (total observation 5227 patient-years; median 5.9 years). Loss to follow-up was negligible (n = 15). A total of 2251 protocol biopsies and 1214 biopsies for cause were performed. All rejections and clinical borderline rejections in protocol biopsies were treated.

RESULTS

Overall 10-year patient survival was 78%, with inferior survival of patients with graft loss and superior survival of patients with living-donor transplantation. Eight factors were common in the models at 3 and 12 months, including age, pre-transplant heart failure and a score of cardiovascular disease and type 2 diabetes, post-transplant urinary tract infection, treatment of rejection, new-onset heart failure, coronary events and malignancies. Additional variables of the model at 3 months included deceased donor transplantation, transplant lymphocele, BK virus nephropathy and severe infections. Graft function and graft loss were significant factors of the model at 12 months. Internal validation and validation with a separate cohort of patients (n = 349) demonstrated good discrimination of the models.

CONCLUSIONS

The identified factors indicate the important areas that need special attention in the pre- and post-transplant care of renal transplant patients. On the basis of these models, we provide nomograms as a tool to weigh individual risks that may contribute to decreased survival.

Characterizing the pharmacokinetics and pharmacodynamics of immunosuppressant medicines and patient outcomes in elderly renal transplant patients

This review examines what is currently known about the pharmacokinetics and pharmacodynamics of commonly prescribed immunosuppressant medicines, tacrolimus, cyclosporine, mycophenolate and prednisolone, in elderly renal transplant recipients, and reported patient outcomes in this cohort. Renal transplantation is increasing rapidly in the elderly, however, currently, long-term patient outcomes are relatively poor compared to younger adults. Some studies have suggested that elderly recipients may have higher dose-adjusted exposure and/or lower clearance of the calcineurin inhibitors tacrolimus and cyclosporine; with one study reporting up to 50% reduction in tacrolimus exposure in the elderly. Elderly transplant recipients do not appear to have higher dosage-adjusted exposure to mycophenolic acid (MPA). The effects of ageing on the pharmacokinetics of prednisolone are unknown. Only one study has examined how aging effects drug target enzymes, reporting no difference in baseline inosine 5'-monophosphate dehydrogenase (IMPDH) activity and MPA-induced IMPDH activity in elderly compared to younger adult renal transplant recipients. In elderly transplant recipients, immunosenescence likely lowers the risk of acute rejection, but increases the risk of drug-related adverse effects. Currently, the three main causes of death in elderly renal transplant recipients are cardiovascular disease, infection and malignancy. One study has showed that renal transplant recipients aged over 65 years are seven times more likely to die with a functioning graft compared with young adults (aged 18-29 years). This suggests that an optimal balance between immunosuppressant medicine efficacy and toxicity is not achieved in elderly recipients, and further studies are needed to foster long-term graft and patient survival. Lower maintenance immunosuppressant targets in elderly recipients may decrease patient susceptibility to drug side effects, however, further studies are required and appropriate targets need to be established.

Risk Factors for Early Graft Failure and Death After Kidney Transplantation in Recipients Older Than 70 Years

INTRODUCTION

Although kidney transplantation carries a survival benefit compared with dialysis, mortality, especially the first year after transplantation, is high in recipients older than 70. The aim of this study was to evaluate early death and graft failure, and to determine the risk factors associated with these events in this specific population.

METHODS

All patients older than 70 years who received a kidney transplant between January 2000 and December 2014 in the North-West of France were included (n = 171). Baseline characteristics and outcomes after transplantation were studied. Kaplan-Meier analysis was performed to assess patient and graft survival, and Cox regression analysis to evaluate risk factors for graft failure and patient death.

RESULTS

The mean recipient age was 73.3 ± 2.5 years. Death-censored graft survival at 1, 3, and 5 years were 82.6%, 78.7%, and 75.4%, respectively. Patient survival at 1, 3, and 5 years was 90.1%, 82.5%, and 68.1%, respectively. One year after transplantation, 17 patients (9.9%) were dead, mainly from infectious (58.5%) or cardiovascular disease (29.4%). According to the Cox multivariate analysis, the independent risk factors for death or graft failure during the first year were arrhythmia (odds ratio [OR] 2.26; 95% confidence interval [CI] 1.08-4.8), left-ventricular ejection fraction (LVEF) under 56% (OR 2.38; 95% CI 1.18-4.83), human leucocyte antigen (HLA) antibodies (OR 2.1; 95% CI 1.04-4.2), deceased donor from cardiovascular cause (OR 5.18; 95% CI 1.22-6.3), and acute rejection (OR 2.77; 95% CI 1.2-6.3).

CONCLUSION

In kidney transplant recipients older than 70 years, cardiac evaluation and immunosuppression optimization seem to be crucial to improve short-term patient and graft survival.

Use of Mammalian Target of Rapamycin Inhibitors for Pancreas Transplant Immunosuppression Is Associated With Improved Allograft Survival and Improved Early Patient Survival

OBJECTIVES

Mammalian targets of rapamycin inhibitors (mTORi) are considered second-line immunosuppression agents because of associated increases in rejection and impaired wound healing. Recent reports indicate mTORi have been linked to improved survival, decreased inflammatory response in pancreatitis, and antiproliferative and antiangiogenic activity. Mammalian targets of rapamycin inhibitors have not been extensively analyzed in pancreas transplant recipients.

METHODS

Adults with pancreas and kidney-pancreas transplants from 1987 to 2016 in the United Network for Organ Sharing database were analyzed (N = 25,837). Subjects were stratified into 2 groups: use of mTORi (n = 4174) and use of non-mTORi-based immunosuppression (n = 21,663). The log-rank test compared survival rates. Univariate and multivariate Cox regression analyses assessed patient and graft survival.

RESULTS

Mammalian targets of rapamycin inhibitors were associated with a 7% risk reduction in allograft failure (hazard ratio, 0.931; P = 0.006). Allograft survival rates were significantly different between mTORi versus non-mTORi (P < 0.0001).The mTORi group showed a significantly higher patient survival rate 1, 3, 5, and 10 years posttransplant compared. Patient survival at 15 years was not significantly different.

CONCLUSIONS

The use of mTORi for immunosuppression in pancreas transplant is associated with improved allograft survival and early patient survival posttransplant (up to 10 years).

The future for diagnostic tests of acute kidney injury in critical care: evidence synthesis, care pathway analysis and research prioritisation

BACKGROUND

Acute kidney injury (AKI) is highly prevalent in hospital inpatient populations, leading to significant mortality and morbidity, reduced quality of life and high short- and long-term health-care costs for the NHS. New diagnostic tests may offer an earlier diagnosis or improved care, but evidence of benefit to patients and of value to the NHS is required before national adoption.

OBJECTIVES

To evaluate the potential for AKI in vitro diagnostic tests to enhance the NHS care of patients admitted to the intensive care unit (ICU) and identify an efficient supporting research strategy.

DATA SOURCES

We searched ClinicalTrials.gov, The Cochrane Library databases, Embase, Health Management Information Consortium, International Clinical Trials Registry Platform, MEDLINE, metaRegister of Current Controlled Trials, PubMed and Web of Science databases from their inception dates until September 2014 (review 1), November 2015 (review 2) and July 2015 (economic model). Details of databases used for each review and coverage dates are listed in the main report.

REVIEW METHODS

The AKI-Diagnostics project included horizon scanning, systematic reviewing, meta-analysis of sensitivity and specificity, appraisal of analytical validity, care pathway analysis, model-based lifetime economic evaluation from a UK NHS perspective and value of information (VOI) analysis.

RESULTS

The horizon-scanning search identified 152 potential tests and biomarkers. Three tests, Nephrocheck^® (Astute Medical, Inc., San Diego, CA, USA), NGAL and cystatin C, were subjected to detailed review. The meta-analysis was limited by variable reporting standards, study quality and heterogeneity, but sensitivity was between 0.54 and 0.92 and specificity was between 0.49 and 0.95 depending on the test. A bespoke critical appraisal framework demonstrated that analytical validity was also poorly reported in many instances. In the economic model the incremental cost-effectiveness ratios ranged from £11,476 to £19,324 per quality-adjusted life-year (QALY), with a probability of cost-effectiveness between 48% and 54% when tests were compared with current standard care.

LIMITATIONS

The major limitation in the evidence on tests was the heterogeneity between studies in the definitions of AKI and the timing of testing.

CONCLUSIONS

Diagnostic tests for AKI in the ICU offer the potential to improve patient care and add value to the NHS, but cost-effectiveness remains highly uncertain. Further research should focus on the mechanisms by which a new test might change current care processes in the ICU and the subsequent cost and QALY implications. The VOI analysis suggested that further observational research to better define the prevalence of AKI developing in the ICU would be worthwhile. A formal randomised controlled trial of biomarker use linked to a standardised AKI care pathway is necessary to provide definitive evidence on whether or not adoption of tests by the NHS would be of value.

STUDY REGISTRATION

The systematic review within this study is registered as PROSPERO CRD42014013919.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Long-Term Outcomes among Kidney Transplant Recipients and after Graft Failure: A Single-Center Cohort Study in Brazil

Background

The results of kidney transplantation are impacted by the categories of events responsible for patient death and graft failure. The objective of this study was to evaluate the causes of death and graft failure and outcomes after graft failure among kidney transplant recipients.

Methodology

A retrospective cohort study was conducted with 944 patients who underwent kidney transplantation. Outcomes were categorized in a managed and hierarchical manner.

Results

The crude mortality rate was 10.8% (n=102): in 35.3% cause of death was infection, in 30.4% cardiovascular disease, and in 15.7% neoplasia and in 6.8%, it was not possible to determine the cause of death. The rate of graft loss was 10.6%. The main causes of graft failure were chronic rejection (40%), acute rejection (18.3%), thrombosis (17.3%), and recurrence of primary disease (16.5%). Failures due to an acute rejection occurred earlier than those due to chronic rejection and recurrence (p<0.0001). As late causes of graft loss, death with the functioning kidney occurred earlier than recurrence and chronic rejection (p=0.008). The outcomes after graft failure were retransplantation in 26.1% and death in 21.4%, at a mean of 25.5 and 21.4 months, respectively.

Conclusion

It was possible to identify more than 90% of the events responsible for the deaths of transplanted patients, predominantly infectious and cardiovascular diseases. Among the causes of graft failure, chronic and acute rejections and recurrence were the main causes of graft failure which were followed more frequently by retransplantation than by death on dialysis.

Effect of Age on Leukopenia Following Renal Transplantation at a Single Center

Introduction:

Leukopenia in renal transplant recipients occurs commonly within the first year following transplantation; however, literature on the effects of age on leukopenia is scarce.

Design:

A single-center, retrospective review was conducted on 141 recipients transplanted from January 2011 to December 2015. Transplant recipients were characterized by age <60 years (n = 94) or age 60 years and older (n = 47) for analysis.

Results:

A greater incidence of leukopenia was seen in the older cohort compared to the younger cohort (64% vs 55%). Of those patients who developed leukopenia, the older cohort (n = 30) had a higher incidence of hospitalization for leukopenia (30% vs 23%) but a lower incidence of hospitalization for infection (20% vs 25%) compared to the younger cohort (n = 52). Additionally, one month following mycophenolate mofetil (MMF) discontinuation, the older cohort had reduced recovery of their white blood cell count (+263.8% vs +272.5%) and experienced less recurrent leukopenic episodes (50% vs 67%) and rejection episodes (0% vs 22%) compared to the younger cohort, alluding to the need for less immunosuppression.

Conclusions:

Age at transplantation was not associated with the development of leukopenia; however, older patients had a higher incidence of leukopenia and hospitalization for leukopenia. Dose reduction or discontinuation of MMF should be considered in older kidney transplant recipients who develop leukopenia.

Benefits of kidney transplantation for a national cohort of patients aged 70 years and older starting renal replacement therapy

Our objectives were to evaluate kidney transplantation survival benefit in people aged ≥70 who were receiving renal replacement therapy (RRT) and to identify their risk factors for posttransplant mortality. This study included all patients in the national French Renal Epidemiology and Information Network registry who started RRT between 2002 and 2013 at age ≥70. Mortality risk was compared between patients with transplants; on the waiting list; and on dialysis matched for age, gender, comorbidities, and time on dialysis. Of the 41 716 elderly patients starting RRT, 1219 (2.9%) were on the waiting list and 877 (2.1%) underwent transplantation during the follow-up. Until month 3, transplant patients had a risk of death triple that of the wait-listed group. Although the risk was halved at month 9, the perioperative risk was still not offset by month 36. Compared with matched dialysis patients (n = 2183), transplant patients were not at significantly increased perioperative risk and had a lower mortality risk starting at month 3. Risk factors for posttransplant mortality were diabetes, cardiovascular comorbidities, and dialysis duration >2 years. Among older dialysis patients, 20% had neither cardiovascular comorbidity nor diabetes. Systematic early assessment of the eligibility of elderly patients for kidney transplantation is recommended to expand registration to patients with poor survival on dialysis and no cardiovascular comorbidity.

Rapamycin Prolongs Graft Survival and Induces CD4+IFN-γ+IL-10+ Regulatory Type 1 Cells in Old Recipient Mice

BACKGROUND

Although the elderly represents a rapidly growing population among transplant recipients, age-specific aspects have not been considered sufficiently in clinical trials. Moreover, age-specific effects of immunosuppressive therapies remain poorly understood.

METHODS

Here, we assessed the impact of rapamycin on alloimmune responses in old recipients using a fully major histocompatibility complex-mismatched murine transplantation model.

RESULTS

Old untreated recipients displayed a prolonged skin graft survival compared to their young counterparts, an observation that confirmed data of our previous experiments. Rapamycin led to a significant prolongation of graft survival in both young and old recipients. However, graft survival was age-dependent and extended in old versus young recipients (19 days vs 12 days, P = 0.004). This age-specific effect was not linked to changes in frequencies or subset composition of either cluster of differentiation (CD)8 or CD4 T cells. Moreover, antiproliferative effects of rapamycin on CD8 and CD4 T cells as assessed by in vivo bromdesoxyuridine incorporation were comparable and age-independent. In contrast, the systemic production of IL-10 was markedly elevated in old recipients treated with rapamycin. In parallel to this shift in cytokine balance, IFN-γ/IL-10 double-positive regulatory type 1 cells emerged during T helper type 1 differentiation of old T helper cells in presence of rapamycin. Similarly, CD4IFN-γIL-10 cells expanded among Foxp3-negative cells after in vivo treatment of old recipients with rapamycin.

CONCLUSIONS

Our results highlight novel aspects of age-dependent immunosuppressive effects of rapamycin, with relevance for age-specific immunosuppressive regimens.

The influence of clinical, environmental, and socioeconomic factors on five-year patient survival after kidney transplantation

INTRODUCTION

The risk of death after kidney transplant is associated with the age of the recipient, presence of comorbidities, socioeconomic status, local environmental characteristics and access to health care.

OBJECTIVE

To investigate the causes and risk factors associated with death during the first 5 years after kidney transplantation.

METHODS

This was a single-center, retrospective, matched case-control study.

RESULTS

Using a consecutive cohort of 1,873 kidney transplant recipients from January 1st 2007 to December 31st 2009, there were 162 deaths (case group), corresponding to 5-year patient survival of 91.4%. Of these deaths, 25% occurred during the first 3 months after transplant. The most prevalent cause of death was infectious (53%) followed by cardiovascular (24%). Risk factors associated with death were history of diabetes, dialysis type and time, unemployment, delayed graft function, number of visits to center, number of hospitalizations, and duration of hospital stay. After multivariate analysis, only time on dialysis, number of visits to center, and days in hospital were still associated with death. Patients who died had a non-significant higher number of treated acute rejection episodes (38% vs. 29%, p = 0.078), higher mean number of adverse events per patient (5.1 ± 3.8 vs. 3.8 ± 2.9, p = 0.194), and lower mean eGFR at 3 months (50.8 ± 25.1 vs. 56.7 ± 20.7, p = 0.137) and 48 months (45.9 ± 23.8 vs. 58.5 ± 20.2, p = 0.368).

CONCLUSION

This analysis confirmed that in this population, infection is the leading cause of mortality over the first 5 years after kidney transplantation. Several demographic and socioeconomic risk factors were associated with death, most of which are not readily modifiable.

Multiple-frequency bioimpedance devices for fluid management in people with chronic kidney disease receiving dialysis: a systematic review and economic evaluation

BACKGROUND

Chronic kidney disease (CKD) is a long-term condition requiring treatment such as conservative management, kidney transplantation or dialysis. To optimise the volume of fluid removed during dialysis (to avoid underhydration or overhydration), people are assigned a 'target weight', which is commonly assessed using clinical methods, such as weight gain between dialysis sessions, pre- and post-dialysis blood pressure and patient-reported symptoms. However, these methods are not precise, and measurement devices based on bioimpedance technology are increasingly used in dialysis centres. Current evidence on the role of bioimpedance devices for fluid management in people with CKD receiving dialysis is limited.

OBJECTIVES

To evaluate the clinical effectiveness and cost-effectiveness of multiple-frequency bioimpedance devices versus standard clinical assessment for fluid management in people with CKD receiving dialysis.

DATA SOURCES

We searched major electronic databases [e.g. MEDLINE, MEDLINE In-Process & Other Non-Indexed Citations, EMBASE, Science Citation Index and Cochrane Central Register of Controlled Trials (CENTRAL)] conference abstracts and ongoing studies. There were no date restrictions. Searches were undertaken between June and October 2016.

REVIEW METHODS

Evidence was considered from randomised controlled trials (RCTs) comparing fluid management by multiple-frequency bioimpedance devices and standard clinical assessment in people receiving dialysis, and non-randomised studies evaluating the use of the devices for fluid management in people receiving dialysis. One reviewer extracted data and assessed the risk of bias of included studies. A second reviewer cross-checked the extracted data. Standard meta-analyses techniques were used to combine results from included studies. A Markov model was developed to assess the cost-effectiveness of the interventions.

RESULTS

Five RCTs (with 904 adult participants) and eight non-randomised studies (with 4915 adult participants) assessing the use of the Body Composition Monitor [(BCM) Fresenius Medical Care, Bad Homburg vor der Höhe, Germany] were included. Both absolute overhydration and relative overhydration were significantly lower in patients evaluated using BCM measurements than for those evaluated using standard clinical methods [weighted mean difference -0.44, 95% confidence interval (CI) -0.72 to -0.15, p = 0.003, I2 = 49%; and weighted mean difference -1.84, 95% CI -3.65 to -0.03; p = 0.05, I2 = 52%, respectively]. Pooled effects of bioimpedance monitoring on systolic blood pressure (SBP) (mean difference -2.46 mmHg, 95% CI -5.07 to 0.15 mmHg; p = 0.06, I2 = 0%), arterial stiffness (mean difference -1.18, 95% CI -3.14 to 0.78; p = 0.24, I2 = 92%) and mortality (hazard ratio = 0.689, 95% CI 0.23 to 2.08; p = 0.51) were not statistically significant. The economic evaluation showed that, when dialysis costs were included in the model, the probability of bioimpedance monitoring being cost-effective ranged from 13% to 26% at a willingness-to-pay threshold of £20,000 per quality-adjusted life-year gained. With dialysis costs excluded, the corresponding probabilities of cost-effectiveness ranged from 61% to 67%.

LIMITATIONS

Lack of evidence on clinically relevant outcomes, children receiving dialysis, and any multifrequency bioimpedance devices, other than the BCM.

CONCLUSIONS

BCM used in addition to clinical assessment may lower overhydration and potentially improve intermediate outcomes, such as SBP, but effects on mortality have not been demonstrated. If dialysis costs are not considered, the incremental cost-effectiveness ratio falls below £20,000, with modest effects on mortality and/or hospitalisation rates. The current findings are not generalisable to paediatric populations nor across other multifrequency bioimpedance devices.

FUTURE WORK

Services that routinely use the BCM should report clinically relevant intermediate and long-term outcomes before and after introduction of the device to extend the current evidence base.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42016041785.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

[Focusing on kidney transplantation in the elderly]

Due to the increase in life expectancy and the ageing of end-stage renal disease patients, the number of patients older than 65 years receiving a kidney transplant has been continuously growing over the last fifteen years. The benefits of renal transplantation compared to dialysis in terms of survival and quality of life have been shown in selected recipients over 65, or 70 years. However, the age remains the main limiting factor for the access to the waiting list, and the reluctance of the clinicians can be explained by the multiple comorbidities of these candidates, their limited life expectancy or the shortage of grafts. The challenge is to select the candidates who can benefit from renal transplantation, thanks to rigorous cardiovascular and neoplastic evaluation before enrolment and by taking into account the specific characteristics of elderly patients. The living donor appears to be the ideal option for elderly recipients, the alternative being the extended criteria donor, allowing waiting times to be limited. The choice of immunosuppressive therapy is also crucial in these patients at high risk of infectious and cardiovascular complications in whom the occurrence of acute rejection can have severe consequences. There are currently no specific recommendations for immunosuppression in elderly recipients, and we would need large-scale randomized studies to improve the prognosis of renal transplantation in this population.

Risk Factors for Melanoma in Renal Transplant Recipients

Importance

Melanoma risk factors and incidence in renal transplant recipients can inform decision making for both patients and clinicians.

Objective

To determine risk factors and characteristics of renal transplant recipients who develop melanoma.

Design, Setting, and Participants

This cohort study of a large national data registry used a cohort of renal transplant recipients from the United States Renal Data System (USRDS) database from the years 2004 through 2012. Differences in baseline characteristics between those who did and did not develop melanoma were examined, and a survival analysis was performed. Patients with renal transplants who received a diagnosis of melanoma according to any inpatient or outpatient claim associated with a billing code for melanoma were included. A history of pretransplant melanoma, previous kidney transplantation, or transplantation after 2012 or before 2004 were exclusion criteria. The data analysis was conducted from 2015 to 2016.

Exposure

Receipt of a renal transplant.

Main Outcomes and Measures

Incidence and risk factors for melanoma.

Results

Of 105 174 patients (64 151 [60.7%] male; mean [SD] age, 49.6 [15.3] years) who received kidney transplants between 2004 and 2012, 488 (0.4%) had a record of melanoma after transplantation. Significant risk factors for developing melanoma vs not developing melanoma included older age among recipients (mean [SD] age, 60.5 [10.2] vs 49.7 [15.3] years; P < .001) and donors (42.6 [15.0] vs 39.2 [15.1] years; P < .001), male sex (71.5% vs 60.7%; P < .001), recipient (96.1% vs 66.5%; P < .001) and donor (92.4% vs 82.9%; P < .001) white race, less than 4 HLA mismatches (44.9% vs 37.1%; P = .001), living donors (44.7% vs 33.7%; P < .001), and sirolimus (22.3% vs 13.2%; P < .001) and cyclosporine (4.9% vs 3.2%; P = .04) therapy. Risk factors significant on survival analysis included older recipient age (hazard ratio [HR] per year, 1.06; 95% CI, 1.05-1.06; P < .001), recipient male sex (HR, 1.53; 95% CI, 1.25-1.88; P < .001), recipient white race, living donors (HR, 1.35; 95% CI, 1.11-1.64; P = .002), and sirolimus (HR, 1.54; 95% CI, 1.22-1.94; P < .001) and cyclosporine (HR, 1.93; 95% CI, 1.24-2.99; P = .004) therapy. The age-standardized relative rate of melanoma in USRDS patients compared with Surveillance, Epidemiology, and End Results patients across all years was 4.9. A Kaplan-Meier estimate of the median time to melanoma among those patients who did develop melanoma was 1.45 years (95% CI, 1.31-1.70 years).

Conclusions and Relevance

Renal transplant recipients had greater risk of developing melanoma than the general population. We believe that the risk factors we identified can guide clinicians in providing adequate care for patients in this vulnerable group.

Strategies for an Expanded Use of Kidneys From Elderly Donors

The old-for-old allocation policy used for kidney transplantation (KT) has confirmed the survival benefit compared to remaining listed on dialysis. Shortage of standard donors has stimulated the development of strategies aimed to expand acceptance criteria, particularly of kidneys from elderly donors. We have systematically reviewed the literature on those different strategies. In addition to the review of outcomes of expanded criteria donor or advanced age kidneys, we assessed the value of the Kidney Donor Profile Index policy, preimplantation biopsy, dual KT, machine perfusion and special immunosuppressive protocols. Survival and functional outcomes achieved with expanded criteria donor, high Kidney Donor Profile Index or advanced age kidneys are poorer than those with standard ones. Outcomes using advanced age brain-dead or cardiac-dead donor kidneys are similar. Preimplantation biopsies and related scores have been useful to predict function, but their applicability to transplant or refuse a kidney graft has probably been overestimated. Machine perfusion techniques have decreased delayed graft function and could improve graft survival. Investing 2 kidneys in 1 recipient does not make sense when a single KT would be enough, particularly in elderly recipients. Tailored immunosuppression when transplanting an old kidney may be useful, but no formal trials are available.Old donors constitute an enormous source of useful kidneys, but their retrieval in many countries is infrequent. The assumption of limited but precious functional expectancy for an old kidney and substantial reduction of discard rates should be generalized to mitigate these limitations.

Age-Dependent Metabolic and Immunosuppressive Effects of Tacrolimus

Immunosuppression in elderly recipients has been underappreciated in clinical trials. Here, we assessed age-specific effects of the calcineurin inhibitor tacrolimus (TAC) in a murine transplant model and assessed its clinical relevance on human T cells. Old recipient mice exhibited prolonged skin graft survival compared with young animals after TAC administration. More important, half of the TAC dose was sufficient in old mice to achieve comparable systemic trough levels. TAC administration was able to reduce proinflammatory interferon-γ cytokine production and promote interleukin-10 production in old CD4⁺ T cells. In addition, TAC administration decreased interleukin-2 secretion in old CD4⁺ T cells more effectively while inhibiting the proliferation of CD4⁺ T cells in old mice. Both TAC-treated murine and human CD4⁺ T cells demonstrated an age-specific suppression of intracellular calcineurin levels and Ca²⁺ influx, two critical pathways in T cell activation. Of note, depletion of CD8⁺ T cells did not alter allograft survival outcome in old TAC-treated mice, suggesting that TAC age-specific effects were mainly CD4⁺ T cell mediated. Collectively, our study demonstrates age-specific immunosuppressive capacities of TAC that are CD4⁺ T cell mediated. The suppression of calcineurin levels and Ca²⁺ influx in both old murine and human T cells emphasizes the clinical relevance of age-specific effects when using TAC.