Pretransplant Dialysis Research Articles

Dialysis Modality, Transplant Characteristics, and Incident Atrial Fibrillation After Kidney Transplant: An Observational Study Using USRDS Data

Atrial fibrillation is the most common arrhythmia and is increasing in prevalence. The prevalence of atrial fibrillation is high among patients receiving dialysis, affecting ∼21.3% of the patients receiving hemodialysis and 15.5% of those receiving peritoneal dialysis. The association of previous dialysis modality with incident atrial fibrillation in patients after receiving their first kidney transplant has not been studied. We used the United States Renal Data System to retrospectively identify adult, Medicare-insured patients who received their first kidney transplant between January 1, 2005, and September 30, 2012 and who had not previously been diagnosed with atrial fibrillation. The study included 43,621 patients who were aged 18 years older when receiving a first kidney transplant between January 1, 2005, and September 30, 2012 and whose primary payer was Medicare (parts A and B) at the time of transplantation and the 6 months preceding it. Dialysis modality used before transplant. Time to incidence of atrial fibrillation up to 3 years posttransplant. Multivariable Cox regression was used to estimate HRs. Of 43,621 patients, 84.9% received hemodialysis and 15.1% received peritoneal dialysis before transplant. The mean±SD age was 51±13.6 years; 60.8% were male, 55.6% White, and 35.8% Black race. The mean dialysis vintage was 4.3±2.8 years. Newly diagnosed atrial fibrillation after kidney transplant occurred in 286 patients (during 15,363 person-years) who had received peritoneal dialysis and in 2,315 patients (during 83,536 person-years) who had received hemodialysis.After multivariable adjustment, atrial fibrillation was 20% (95% CI, 4%-38%) more likely in those who had been receiving hemodialysis versus peritoneal dialysis, regardless of whether death was considered a competing risk or a censoring event. Each year of pretransplant dialysis vintage increased the risk of posttransplant atrial fibrillation by 6% (95% CI, 3%-9%). Residual confounding; data from billing claims does not specify the duration of atrial fibrillation or whether it is valvular. Pretransplant hemodialysis, as compared with peritoneal dialysis, was associated with higher risk of newly diagnosed atrial fibrillation after a first kidney transplant. New-onset atrial fibrillation (AF) occurs in 7% of kidney transplant recipients in the first 3 years posttransplantation. We conducted this study to determine whether pretransplant dialysis modality was associated with posttransplant AF. We identified 43,621 patients; 84.9% used hemodialysis and 15.1% used peritoneal dialysis pretransplant. Multivariable Cox regression was used to estimate hazard ratios. We found that patients receiving hemodialysis pretransplant were at 20% increased risk of developing posttransplant AF as compared with patients receiving peritoneal dialysis. As our understanding of transplant-specific risk factors for AF increases, we may be able to better risk-stratify transplant patients and develop monitoring and management strategies that can improve outcomes.

Simultaneous heart-kidney transplant compared with heart transplant alone in patients with borderline renal function who are not dialysis dependent

ObjectiveThis study assessed characteristics and outcomes of patients who are not dependent on dialysis receiving simultaneous heart kidney transplantation versus heart transplantation alone (HTA) to identify optimal eGFR threshold where combined transplant strategy may be superior. MethodsThis study retrospectively analyzed 7896 adult patients with estimated glomerular filtration rate (eGFR) <60 mL/minute from the United Network for Organ Sharing database who received HTA or simultaneous heart kidney transplant between 2005 and 2021, excluding those who received pretransplant dialysis. Subjects were further stratified into 3 groups based on chronic kidney disease stage at time of transplant: Stage 3A (eGFR 45-59 mL/minute; n = 5044), Stage 3B (eGFR 30-44 mL/minute; n = 2193), and Stage 4 or 5 (eGFR <30 mL/minute; n = 659). Outcomes of interest were all-cause mortality, cardiac allograft failure, and freedom from chronic dialysis or renal transplant following heart transplant. ResultsSimultaneous heart kidney transplant and HTA recipients differed in various baseline characteristics. Simultaneous heart kidney transplant recipients with eGFR <45 mL/minute had greater short- and long-term overall survival and cardiac allograft survival compared with HTA, as well as greater long-term freedom from chronic dialysis or renal transplant. These results were consistent with both propensity matched analyses and multivariable Cox regression analysis of 10 year outcomes. Optimal cutoff value for pretransplant eGFR in predicting elevated risk of renal failure in recipients of heart transplant alone was found to be eGFR ∼45 mL/minute. ConclusionsSimilar to patients with eGFR <30 mL/minute, patients with eGFR 30 to 44 mL/minute who underwent simultaneous heart kidney transplant had superior outcomes compared with HTA, suggesting possible benefit of combined transplant strategy for this subset of heart transplant candidates.

Characteristics of Kidney Transplant Recipients with Prolonged Pre-Transplant Dialysis Duration as Identified by Machine Learning Consensus Clustering: Pathway to Personalized Care.

Longer pre-transplant dialysis duration is known to be associated with worse post-transplant outcomes. Our study aimed to cluster kidney transplant recipients with prolonged dialysis duration before transplant using an unsupervised machine learning approach to better assess heterogeneity within this cohort. We performed consensus cluster analysis based on recipient-, donor-, and transplant-related characteristics in 5092 kidney transplant recipients who had been on dialysis ≥ 10 years prior to transplant in the OPTN/UNOS database from 2010 to 2019. We characterized each assigned cluster and compared the posttransplant outcomes. Overall, the majority of patients with ≥10 years of dialysis duration were black (52%) or Hispanic (25%), with only a small number (17.6%) being moderately sensitized. Within this cohort, three clinically distinct clusters were identified. Cluster 1 patients were younger, non-diabetic and non-sensitized, had a lower body mass index (BMI) and received a kidney transplant from younger donors. Cluster 2 recipients were older, unsensitized and had a higher BMI; they received kidney transplant from older donors. Cluster 3 recipients were more likely to be female with a higher PRA. Compared to cluster 1, cluster 2 had lower 5-year death-censored graft (HR 1.40; 95% CI 1.16-1.71) and patient survival (HR 2.98; 95% CI 2.43-3.68). Clusters 1 and 3 had comparable death-censored graft and patient survival. Unsupervised machine learning was used to characterize kidney transplant recipients with prolonged pre-transplant dialysis into three clinically distinct clusters with variable but good post-transplant outcomes. Despite a dialysis duration ≥ 10 years, excellent outcomes were observed in most recipients, including those with moderate sensitization. A disproportionate number of minority recipients were observed within this cohort, suggesting multifactorial delays in accessing kidney transplantation.

Role of standard HLA mismatch in modifying associations between non-pharmacologic risk factors and solid organ malignancy after kidney transplantation

BackgroundHuman leukocyte antigen mismatch(es) (HLA-mm) between donors and recipients has not been extensively studied either as a risk factor for solid organ malignancy (SOM) or as a modifier of associations between nonpharmacologic risk factors and SOM in kidney transplant recipients (KTRs). MethodsIn a secondary analysis from a previous study, 166,256 adult KTRs in 2000–2018 who survived the first 12 months post-transplant free of graft loss or malignancy were classified into 0, 1–3, and 4–6 standard HLA-mm cohorts. Multivariable cause-specific Cox regressions analyzed the risks of SOM and all-cause mortality (ac-mortality) in 5 years following the first KT year. Comparisons of associations between SOM and risk factors in HLA mismatch cohorts were made by estimating the ratios of adjusted hazard ratios. ResultsCompared with 0 HLA-mm, 1–3 HLA-mm was not associated, and 4–6 HLA-mm was equivocally associated with increased risk of SOM [hazard ratio, (HR) = 1.05, 95%, confidence interval (CI) = 0.94–1.17 and HR = 1.11, 95% CI = 1.00–1.34, respectively]. Both 1–3 HLA-mm and 4–6 HLA-mm were associated with increased risk of ac-mortality compared with 0 HLA mm [hazard ratio (HR) = 1.12, 95%, Confidence Interval (CI) = 1.08–1.18) and (HR = 1.16, 95% CI = 1.09–1.22), respectively]. KTR's history of pre-transplant cancer, age 50–64, and >/=65 years were associated with increased risks of SOM and ac-mortality in all HLA mismatch cohorts. Pre-transplant dialysis >2 years, diabetes as the primary renal disease, and expanded or standard criteria deceased donor transplantation were risk factors for SOM in the 0 and 1–3 HLA-mm cohorts and of ac-mortality in all HLA-mm cohorts. KTRs male sex or history of previous kidney transplant was a risk factor for SOM in the 1–3 and 4–6 HLA-mm cohorts and of ac-mortality in all HLA-mm cohorts. ConclusionDirect association between SOM and the degree of HLA mismatching is equivocal and limited to the 4–6 HLA-mm stratum; however, the degree of HLA mismatching has significant modifying effects on the associations between specific nonpharmacologic risk factors and SOM in KTRs.

Simultaneous Lung-Kidney Transplantation in the United States

BackgroundSimultaneous lung-kidney transplantation is rarely performed. Contemporary national practice trends and outcomes are unclear. MethodsFrom the United Network for Organ Sharing database, we identified 108 lung-kidney transplant recipients (2005-2022). They were compared with isolated lung recipients with pretransplantation dialysis or estimated glomerular filtration rate (eGFR) ≤30 mL/min per 1.73 m2 (n = 372) and isolated non–dialysis-dependent lung recipients with 30 < eGFR < 50 mL/min per 1.73 m2 (n = 1416), respectively. Lung-kidney recipients were also compared with recipients of the contralateral kidney from the same donors (n = 90). ResultsLung-kidney transplantation was performed by 36 centers, with increasing annual volume (1 in 2005, 16 in 2022; P < .01). Forty percent (44/108) of lung-kidney recipients received pretransplantation dialysis, and of those without pretransplantation dialysis, median eGFR was 30.7 mL/min per 1.73 m2. Lung-kidney recipients had improved survival compared with isolated lung recipients with eGFR ≤30 mL/min per 1.73 m2 or pretransplantation dialysis (adjusted hazard ratio, 0.59; 95% CI, 0.38-0.92). However, no survival benefit was observed when lung-kidney recipients were compared with isolated lung recipients with 30 < eGFR < 50 mL/min per 1.73 m2 and no pretransplantation dialysis (adjusted hazard ratio, 0.88; 95% CI, 0.55-1.41). Compared with isolated kidney recipients using the contralateral kidney from the same donors, lung-kidney recipients had a higher risk of kidney allograft loss (adjusted hazard ratio, 3.27; 95% CI, 1.22-8.78), a difference largely accounted for by patient death with a functioning kidney allograft. ConclusionsRecipients of lung-kidney transplants had improved survival compared with isolated lung recipients with eGFR ≤30 mL/min per 1.73 m2 or pretransplantation dialysis. However, lung-kidney recipients had a higher rate of kidney allograft loss than recipients of the contralateral kidney allograft from the same donors.

#4769 EFFECT OF EXTREMELY LONG DIALYSIS VINTAGE ON RENAL ALLOGRAFT SURVIVAL: A SINGLE-CENTER EXPERIENCE

Abstract Background and Aims Dialysis vintage is long in kidney transplant recipients (KTRs) due to the donor shortage in Turkey. We assessed the effect of pre-transplant dialysis duration (more than 10 years) on the outcomes of renal allografts. Method We retrospectively evaluated 480 KTRs who were grafted between January 2009 and October 2020 at Ankara University School of Medicine, Ibni Sina Hospital. KTRs were divided into two groups according to the duration of pre-transplant dialysis treatment: Group A, ≥10 years and Group B, &amp;lt;10 years. Data on demographics, comorbidities, immunologic properties and graft survivals were compared between the two groups. Results Group A included 60 patients and dialysis vintage was 288±60 months (Table 1). 420 patients in Group B had an average of 19 months period of dialysis treatment. While cadaveric transplantation was 78.3% in Group A, it was much lower in Group B (11.2%, p&amp;lt;0.001). Most of the patients were on hemodialysis treatment (95.0% vs. 58.3%, respectively, P = .001). Recipients’ age (P = .001), HLA mismatch number (P = .008) and PRA positivity (P = .001) were significantly higher in Group A. Although anti-human T-thymocyte globulin had been mostly chosen for induction therapy in Group A (p&amp;lt;0.001); almost all patients were under standard triple maintenance immunosuppression therapy. First year and late acute rejection rates were similar between two groups (p=1.000 and P = .407, respectively). Clinically important difference was demonstrated in graft loss, which was mostly seen in the ≥10 years dialysis group (Group A, 18.3% vs. Group B, 8.3%, P = .014). The 1-, and 5- years graft survival rates were 91.4%, and 81.3%, respectively, in Group A and 97.4%, and 93.4%, respectively, in Group B (P = .034 and P = .029, respectively). Patient loss was significantly higher in Group A (Group A, 28.3% vs. Group B, 14.3%, P = .018). Conclusion We demonstrated that pre-transplant dialysis duration for more than 10 years has adverse effects on post-transplant graft and patient outcomes, accompanied by high immunological risk. Updates of organ allocation system considering sensitized candidates and strategies to expand donor pool and donation rates are needed to reduce waiting times on dialysis.

#5729 HIGHER DAILY PROTEIN INTAKE CAN IMPROVE THE GRAFT FUNCTION OF KIDNEY TRANSPLANT RECIPIENTS IN THE EARLY POSTTRANSPLANT PERIOD

Abstract Background and Aims Protein-energy wasting (PEW) is commonly seen among uremic patients, which may still exist after they received kidney transplantation,[1,2] and it is a determining factor in the progression of chronic kidney disease (CKD).[3] The use of immunosuppressants and glucocorticoids after transplantation will also affect the patients' metabolism and aggravate their malnutrition.[4,5] Adequate daily protein intake (DPI) in the early posttransplant period facilitates the rapid recovery of surgical wounds.[6] However, few studies focused on the impact of DPI on the early recovery of graft function. This study aimed to explore the relationship between DPI and graft function at month 3 posttransplant, which may provide a basis for clinical nutritional regimen of kidney transplant recipients. Method This is a retrospective observational study. 176 kidney transplant recipients (KTRs) who underwent kidney transplant in West China Hospital from December 2021 to June 2022 were included and followed up regularly. 24-hour urine urea data were collected at month 3 posttransplant to calculate their DPI. These KTRs were further divided into two groups according to the recommended DPI for KTRs by the 2021 Practice Guidelines for the Nutritional Management of Chronic Kidney Disease,[7] namely high intake group (Group 1, with DPI ≥ 1.4g/kg·d, n = 66) and low intake group (Group 2, with DPI &amp;lt; 1.4g/kg·d, n = 110). Laboratory data and posttransplant adverse events within 3 months were recorded. Multiple logistic regression was used to analyze the relationship between DPI and early posttransplant graft function. Results Mean DPI levels at month 3 posttransplant were 1.75±0.56 g/kg·d in Group 1 and 0.98±0.24 g/kg·d in Group 2, respectively. There was no significant difference in age, gender, pretransplant body mass index (BMI), dialysis type and time, donor type, or the ratio of delayed graft function (DGF) between the two groups. The levels of estimated glomerular filtration rate (eGFR), body mass index(BMI), hemoglobin (Hb), high-density lipid-cholesterol (HDL), and urinary protein at month 3 posttransplant in Group 1 were significantly higher than those in Group 2 (P &amp;lt; 0.005, Fig. 1). No statistical difference was found in the incidence of adverse events between the two groups at month 3 posttransplant. The results of multiple logistic regression analysis showed that higher DPI in the early posttransplant period was a protective factor for graft function after kidney transplantation. Conclusion In the early posttransplant period, higher dietary protein intake (DPI ≥ 1.4 g/kg·d) may improve graft kidney function, lipid metabolism, and renal anemia.

#2502 THE FREQUENCY AND RISK FACTORS OF NODAT AND ELECTROLYTE DISORDERS IN KIDNEY TRANSPLANT PATIENTS

Abstract Background and Aims The purpose of the study is to investigate at the incidence and risk factors for post-transplant diabetes mellitus (PTDM) in non-diabetic kidney transplant patients (KTrs). Method The study included 120 KTRs who did not have diabetes in the pretransplant period. The diagnosis of PTDM was made according to the 2003 ADA DM diagnostic criteria. The relationship between PTDM and clinical and laboratory data on the 0th, 1st, 3rd, 6th, 12th and 24th months was investigated. Results The mean age of the patients was 33.3±11.5 years, 65% (78) of them were male. PTDM was developed in 29.1% (35) and 80% of PTDM at first 3 months. The risk factors for PTDM were found to be older (4.4%), family history of diabetes mellitus (5.24 times), beta-blocker use (2.55 times). KTRs with and without PTDM; Pretransplant dialysis type (Hemodialysis (P=0.822) and Peritoneal dialysis (P = .583)), living donor (101/84.2%)/cadaveric donor (19/ 15.8%), donor age and gender were similar. Serum magnesium and potassium were different only in the first month between the groups with and without PTDM (P = .019 and 0.008 respectively). The negative effect of PTDM on GFR was not observed in the 2-year follow-up. Conclusion It can be predicted that diabetes mellitus may develop with a family history of diabetes, advanced age and the use of beta-blockers. The risk of developing PTDM is higher in the first 3 months and hypomagnesemia in the first month may contribute to diabetes development.

Factors Influencing Short-Term Patient Survival in Elderly Kidney Transplant Recipients

For the average patient with end-stage renal disease, kidney transplantation improves quality of life and prolongs survival compared with patients on the transplant waiting list who remain on dialysis. Patients ≥65 years of age represent an increasing proportion of adults with end-stage renal disease, and kidney transplantation outcomes remain controversial in this population. The aim of this study was to evaluate factors that may increase 1-year mortality after renal transplantation in older recipients. A retrospective study that included 147 patients (75.5% men) ≥65 years old (mean age 67.5 ± 2 years) who were transplanted between January 2011 and December 2020. The mean follow-up was 52.6 ± 27.2 months. Rehospitalization (<1 year) occurred in 39.5% of patients. Infectious complications were present in 18.4% of patients. The overall mortality rate was 23.1%, and 1-year mortality was 6.8%. As 1-year mortality predictors, we found a positive correlation with factors related to kidney transplant, such as cold ischemia time (P=.003), increasing donor age (P=.001); and factors related to the receptor such as pretransplantation dialysis modality as peritoneal dialysis (P=.04), cardiovascular disease (P=.004), delayed graft function (P=.002), early cardiovascular complications after kidney transplant (P < .001), and early rehospitalizations (P < .001). No correlation was found between 1-year mortality and age, sex, race, body mass index, and type of kidney transplant. A more rigorous pretransplant evaluation, focusing on cardiovascular disease and strict exclusion criteria, is recommended for patients ≥65 years old.

Optimizing Arteriovenous Fistula Care in Kidney Transplant Recipients: A Complex Task.

Optimizing Arteriovenous Fistula Care in Kidney Transplant Recipients: A Complex Task.

Cytopenias in pediatric kidney transplant recipients: preceding factors and clinical consequences.

Kidney trans plantation is associated with secondary complications, including the risk of developing posttransplant cytopenias. This study aimed to evaluate the characteristics, identify predictors, and assess the management and consequences of cytopenias in the pediatric kidney transplant population. This is a single-center retrospective analysis of 89 pediatric kidney transplant recipients. Possible factors preceding cytopenias were compared with the goal of recognizing predictors for posttransplant cytopenias. Posttransplant neutropenias were analyzed for the total study period and separately for the period beyond 6months posttransplant (late neutropenias), to rule out confounding influences of induction and initial intensive therapy. Sixty patients (67%) developed at least one episode of posttransplant cytopenia. All episodes of posttransplant thrombocytopenias were mild or moderate. Posttransplant infections and graft rejection were found to be significant predictors for thrombocytopenia (HR 6.06, 95% CI 1.6-22.9, and HR 5.82, 95% CI 1.27-26.6, respectively). A total of 30% of posttransplant neutropenias were severe (ANC ≤ 500). Pretransplant dialysis and posttransplant infections were significant predictors for late neutropenias (HR 11.2, 95% CI 1.45-86.4, and HR 3.32, 95% CI 1.46-7.57, respectively). Graft rejection occurred in 10% of patients with cytopenia, all following neutropenia, within 3months from cytopenia appearance. In all such cases, mycophenolate mofetil dosing had been held or reduced prior to rejection. Posttransplant infections are substantial contributors to developing posttransplant cytopenias. Preemptive transplantation appears to reduce risk of late neutropenia, the accompanying reduction in immunosuppressive therapy, and the ensuing risk of graft rejection. An alternative response to neutropenia, possibly using granulocyte colony stimulating factor, may diminish graft rejection. A higher resolution version of the Graphical abstract is available as Supplementary information.

Simultaneous heart-kidney transplant in patients with borderline estimated glomerular filtration rate without dialysis dependency.

Appropriate patient selection for simultaneous heart-kidney transplantation (sHK) in patients with moderate renal dysfunction remains challenging. From the United Network for Organ Sharing database (2003-2020), we identified 5678 adults with an estimated pre-transplant glomerular filtration rate (eGFR) between 30 and 45mL/min/1.73m2 and no pre-transplant dialysis. Patients undergoing sHK (n=293) were compared with those undergoing heart transplantation alone (n=5385) using 1:3 propensity score matching. The sHK utilization rate increased from 1.8% in 2003 to 12.2% in 2020 (p<.001). After matching, 1 and 5-year survival was 87.7% (95% confidence interval [CI] 83.3-91.0) and 80.0% (95% CI 74.2-84.6) after sHK, and 87.3% (95% CI 85.2-89.1) and 71.8% (95% CI 68.4-74.9) after heart transplant alone (p=.04). In the subgroup analysis, sHK was associated with a 5-year survival benefit only in patients with 30<eGFR≤35mL/min/1.73m2 (p=.05) but not in those with 35<eGFR<45mL/min/1.73m2 (p=.45). Patients who underwent heart transplants alone also had a higher incidence of becoming chronic dialysis-dependent after transplant within 5-year follow-up (10.2%, 95% CI 8.0-12.6 vs. 3.8%, 95% CI 1.7-7.1, p=.004). The 5-year incidence of subsequent kidney waitlisting and transplants after heart transplants alone was 5.6% and 1.9%, respectively. Among propensity-matched patients without pre-transplant dialysis, compared to heart transplants alone, sHK had improved 5-year survival in those with 30<eGFR≤35 but not in those with 35<eGFR<45mL/min/1.73m2 . One-year survival was similar irrespective of eGFR. Receiving a kidney after a heart transplant alone is rare under the current allocation system.

Process control: simply a matter of efficiency or of survival and costs? A single-centre quality improvement project in living donor renal transplant

BackgroundRising incidence and prevalence of end-stage renal disease is a worldwide concern for sustainability of healthcare systems and societies. Living donor renal transplant [LDRT] provides highest health achievements and cost containment than any alternative form of renal replacement therapy. Nonetheless, about 25% of potential LDRTs are missed for causes directly related with inadequate timing in donor assessment. Our quality improvement (QI) project implement process control tools and strategy aiming at reducing total evaluation time for donor candidates and minimizing dialysis exposure for intended recipients, which are the two main determinants of clinical outcomes and costs.MethodsThe study includes patients who underwent donor nephrectomy between January 1, 2017 and December 31, 2021. Six Sigma DMAIC approach was adopted to assess Base Case performance (Jan2017-Jun2019) and to design and implement our QI project. Study of current state analysis focused on distribution of time intervals within the assessment process, analysis of roles and impacts of involved healthcare providers and identification of targets of improvement. Improved Scenario (Jul2019-Dec2021) was assessed in terms of total lead time reduction, total pre-transplantation dialysis exposure and costs reduction, and increase in pre-emptive transplantations. The study was reported following SQUIRE 2.0 Guidelines for QI projects.ResultsStudy population includes 63 patients, 37 in Base Case and 26 in Improved Scenario. Total lead time reduced from a median of 293 to 166 days and this in turn reduced pre-transplantation dialysis exposure and costs by 45%. Rate of potential pre-emptive donors’ loss changes from 44% to 27%.ConclusionsLean methodology is an effective tool to improve quality and efficiency of healthcare processes, in the interest of patients, healthcare professionals and payers.

Risk Factors for First and Recurrent Fractures among Kidney Transplant Recipients.

Introduction: Kidney transplantation is associated with increased risk of bone fracture. Current literature reports widely variable fracture burden and contains limited data on risk factors for recurrent fractures. Methods: The incidence of all and major osteoporotic fractures (hip, forearm, thoracolumbar, and proximal humerus) were assessed. The risk factors for first and recurrent fractures among 1285 Canadian kidney transplant recipients transplanted between January 1, 2004, and December 31, 2013 were also identified. Results: The 10-year cumulative incidence of all fractures and major osteoporotic fractures in this population was 27.1% (95% CI: 22.5, 32.4) and 17.8% (95% CI: 13.4, 23.5), respectively. On multivariable analysis, female sex (HR = 1.64 [95% CI: 1.20, 2.26]), history of fracture (HR = 1.54 [95% CI: 1.12, 2.11]), and pretransplant diabetes (HR = 1.85 [95% CI: 1.29, 2.65]) were recipient factors found to increase the risk for any first fracture posttransplant. These risk factors persist in analysis with the time origin 3-months posttransplant, where transplant age (HR = 1.01 [95% CI: 1.00, 1.03]) and increased time on pretransplant dialysis (HR = 1.06 [95% CI: 1.00, 1.12]) also emerge as risk factors for first fracture. On multivariable shared frailty model analysis, increased risk of recurrent fractures was associated with recipient female sex (HR = 1.74 [95% CI: 1.21, 2.51]) and history of diabetes (HR = 1.76 [95% CI: 1.17, 2.66]). Discussion: The results suggested that some risk factors for first fracture may not inform risk of recurrent fractures. As such, fracture risk should be assessed accordingly to optimize long-term care and implement preventive measures.

Heart–kidney transplant versus heart transplant in the obese: a propensity-matched analysis

The decision to perform simultaneous heart-kidneytransplant (HKT) rather than isolated heart transplant (IHT) for patients with advanced kidney disease is challenging. Limited data exist to guide this decision in obese patients. We sought to compare mortality after HKT and IHT in obese patients with non-dialysis-dependent kidney disease. The United Network for Organ Sharing was queried for data on adult heart transplant recipients from 2000 to 2022. Inclusion criteria were obesity, estimated glomerular filtration rate <45 ml/min/1.73 m2 and no pretransplant dialysis. HKT and IHT recipients were propensity matched. Morbidity was compared using chi-squared, Fisher's exact and McNemar's tests. Survival was assessed with Kaplan-Meier estimation. Risk factors for mortality were examined with Cox regression. A total of 289 HKT and 1920 IHT recipients met inclusion criteria. Heart-kidney recipients had higher baseline creatinine and rates of intensive care unit disposition than IHT recipients (both standardized mean differences >0.10). Propensity matching resulted in 239 pairs of HKT and IHT recipients with minimal differences in baseline characteristics. Heart-kidney recipients had higher 5- and 10-year survival than IHT recipients on unmatched (77% vs 69%, P = 0.011 and 58% vs 48%, P = 0.008) and propensity matched analyses (77% vs 68%, P = 0.026 and 57% vs 39%, P = 0.007). Heart-kidney transplantation was protective against 10-year mortality on multivariable regression (hazard ratio 0.585, P = 0.002). In obese patients with non-dialysis-dependent kidney disease, HKT may decrease long-term mortality relative to IHT and should be strongly considered as a preferred treatment.

Effect of Pretransplant Dialysis Vintage on Clinical Outcomes in Deceased Donor Kidney Transplant

Effect of Pretransplant Dialysis Vintage on Clinical Outcomes in Deceased Donor Kidney Transplant

Early Effect of the Circular Model of Kidney Allocation in the United States.

In March 2021, the United States implemented a new kidney allocation system (KAS250) for deceased donor kidney transplantation (DDKT), which eliminated the donation service area-based allocation and replaced it with a system on the basis of distance from donor hospital to transplant center within/outside a radius of 250 nautical miles. The effect of this policy on kidney discards and logistics is unknown. We examined discards, donor-recipient characteristics, cold ischemia time (CIT), and delayed graft function (DGF) during the first 9 months of KAS250 compared with a pre-KAS250 cohort from the preceding 2 years. Changes in discards and CIT after the onset of COVID-19 and the implementation of KAS250 were evaluated using an interrupted time-series model. Changes in allocation practices (biopsy, machine perfusion, and virtual cross-match) were also evaluated. Post-KAS250 saw a two-fold increase in kidneys imported from nonlocal organ procurement organizations (OPO) and a higher proportion of recipients with calculated panel reactive antibody (cPRA) 81%-98% (12% versus 8%; P <0.001) and those with >5 years of pretransplant dialysis (35% versus 33%; P <0.001). CIT increased (mean 2 hours), including among local OPO kidneys. DGF was similar on adjusted analysis. Discards after KAS250 did not immediately change, but we observed a statistically significant increase over time that was independent of donor quality. Machine perfusion use decreased, whereas reliance on virtual cross-match increased, which was associated with shorter CIT. Early trends after KAS250 show an increase in transplant access to patients with cPRA>80% and those with longer dialysis duration, but this was accompanied by an increase in CIT and a suggestion of worsening kidney discards.

Effect of pretransplant dialysis vintage on clinical outcomes in deceased donor kidney transplant

The waiting time for deceased donor kidney transplants (DDKT) is increasing. We evaluated DDKT prognosis according to the pretransplant dialysis vintage. A total of 4117 first-time kidney transplant recipients were enrolled from a prospective nationwide cohort in Korea. DDKT recipients were divided into tertiles according to pretransplant dialysis duration. Graft failure, mortality, and composite were compared between DDKT and living donor kidney transplant (LDKT) recipients. Pretransplant dialysis vintage was longer annually in DDKT recipients. In the subdistribution of the hazard model for the competing risk, the first tertile did not show an increased risk of graft failure compared with LDKT recipients; however, the second and third tertile groups had an increased risk of graft failure compared to LDKT recipients (adjusted hazard ratio [aHR] 3.59; 95% confidence interval [CI] 1.69–7.63; P < 0.001; aHR 2.37; 95% CI 1.06–5.33; P = 0.037). All DDKT groups showed a significantly higher risk of patient death than LDKT, with the highest risk in the third tertile group (aHR 11.12; 95% CI 4.94–25.00; P < 0.001). A longer pretransplant dialysis period was associated with a higher risk of the composite of patient death and graft failure in DDKT recipients. DDKT after a short period of dialysis had non-inferior results on graft survival compared with LDKT.

Association Between Pretransplant Dialysis Modality and Kidney Transplant Outcomes

The benefits and disadvantages of different pretransplant dialysis modalities and their posttransplant outcomes remain unclear in contemporary kidney transplant care. To summarize the available evidence of the association of different pretransplant dialysis modalities, including hemodialysis and peritoneal dialysis (PD), with posttransplant outcomes. MEDLINE, Embase, PubMed, Cochrane Library, Scopus, CINAHL, and gray literature were searched from inception to March 18, 2022 (updated to April 1, 2022), for relevant studies and with no language restrictions. Randomized clinical trials and nonrandomized observational (case-control and cohort) studies that investigated the association between pretransplant dialysis modality and posttransplant outcomes regardless of age or donor sources (living or deceased) were abstracted independently by 2 reviewers. Following Preferred Reporting Items for Systematic Reviews and Meta-analyses and Meta-analysis of Observational Studies in Epidemiology reporting guidelines, 2 reviewers independently extracted relevant information using a standardized approach. Random-effects meta-analysis was used to estimate pooled adjusted hazard ratio (HR) or odds ratio and 95% CI. Primary outcomes included all-cause mortality, overall graft failure, death-censored graft failure, and delayed graft function. Secondary outcomes included acute rejection, graft vessel thrombosis, oliguria, de novo heart failure, and new-onset diabetes after transplant. The study analyzed 26 nonrandomized studies (1 case-control and 25 cohort), including 269 715 patients (mean recipient age range, 14.5-67.0 years; reported proportions of female individuals, 29.4%-66.9%) whose outcomes associated with pretransplant hemodialysis vs pretransplant PD were compared. No significant difference, with very low certainty of evidence, was observed between pretransplant PD and all-cause mortality (13 studies; n = 221 815; HR, 0.92 [95% CI, 0.84-1.01]; P = .08) as well as death-censored graft failure (5 studies; n = 96 439; HR, 0.98 [95% CI, 0.85-1.14]; P = .81). However, pretransplant PD was associated with a lower risk for overall graft failure (10 studies; n = 209 287; HR, 0.96 [95% CI, 0.92-0.99]; P = .02; very low certainty of evidence) and delayed graft function (6 studies; n = 47 118; odds ratio, 0.73 [95% CI, 0.70-0.76]; P < .001; low certainty of evidence). Secondary outcomes were inconclusive due to few studies with available data. Results of the study suggest that pretransplant PD is a preferred dialysis modality option during the transition to kidney transplant. Future studies are warranted to address shared decision-making between health care professionals, patients, and caregivers as well as patient preferences.

A Multiparametric Nomogram for Predicting Delayed Graft Function in Adult Recipients of Pediatric Donor Kidneys

Delayed graft function (DGF) is one of the most common postoperative complications after kidney transplantation. The ability to predict DGF after transplantation can greatly aid clinical decision-making. Several models have been proposed to predict DGF in adult recipients of adult donor kidneys, but there is currently no model to predict DGF in adult recipients of pediatric donor transplants. Therefore, based on our medical records, we retrospectively investigated the pretransplant risk factors of DGF in transplants from pediatric donors to adult recipients. Our center is in compliance with national laws, the Declaration of Istanbul, and the Helsinki Congress. The donors used by us were organs donated after the death of citizens and the participants were neither paid nor coerced. A retrospective review of 84 adult patients who received pediatric donor kidneys at a single center from April 4, 2015 to November 17, 2021 was conducted to investigate the pretransplant risk factors for the development of DGF. DGF was observed in 45 of 68 patients (66.17%) in the training group and 9 of 16 patients (56.25%) in the validation group. Multivariate logistic analysis showed that kidney donor profile index, cold ischemia time, number of human leukocyte antigen mismatches, and pretransplant dialysis duration were significant independent risk factors for DGF. By integrating these 4 factors, we constructed a nomogram model to predict DGF. According to the prediction model, the area under the curve of DGF of the training group and validation group was 0.899 and 0.905, respectively. We have constructed a novel, reliable, and accurate visual nomogram that provides a practical tool for predicting DGF in adult recipients of pediatric donor kidneys.