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Background: Because kidney transplant recipients may be at increased risk for deep vein thrombosis (DVT) following transplantation, we investigated the incidence, risk factors, treatments and outcomes of early DVT among kidney transplant recipients. Methods: An observational, single-centre cohort study was conducted among adult kidney transplant recipients from Jan. 1, 2005, to Dec. 31, 2016 with 1-year followup. Time to DVT was assessed using the Kaplan-Meier method. Cox proportional hazards and linear regression models were used to analyze risk factors for and outcomes of DVT. Results: The cumulative incidence of DVT was 4.25% at 3 months after transplant. In multivariable analysis, the use of depleting induction agents (hazard ratio [HR] 2.13, 95% confidence interval [CI] 1.05-4.35]), white recipient race (HR 1.84. 95% CI 1.08-3.12), the use of kidneys from expanded criteria donors (HR 2.13, 95% CI 1.05-4.32) and lower recipient body mass index (HR 0.95, 95% CI 0.91-1.00) increased the risk for early DVT. Peritransplant DVT prophylaxis was not associated with early DVT. Early DVT was not associated with reduced graft function, death, graft failure or first hospital readmission. Conclusion: Risk factors for early DVT in our cohort of kidney transplant recipients included white recipient race, use of depleting agents, lower recipient body mass index and use of expanded criteria donors. As practice patterns of donor and recipient selection in kidney transplantation evolve, the results of this study may aid in perioperative risk assessments and decision-making about the use of DVT prophylaxis. Contexte : Etant donne que les receveurs de transplantation renale peuvent etre exposes a un risque accru de thrombose veineuse profonde (TVP) apres l'intervention, nous avons voulu examiner l'incidence, les facteurs de risque, les traitements et l'issue de la TVP precoce chez les receveurs de transplantation renale. Methodes : Nous avons procede a une etude de cohorte observationnelle monocentrique aupres d'adultes ayant subi une transplantation renale entre le 1 (er) janvier 2005 et le 31 decembre 2016, suivis pendant 1 an. L'intervalle avant la TVP a ete evalue par la methode de Kaplan-Meier. Des modeles d'analyse a risques proportionnels de Cox et la regression lineaire ont servi pour l'analyse des facteurs de risque et l'issue de la TVP. Resultats : L'incidence cumulative des TVP etait de 4,25 % 3 mois apres la transplantation. Dans l'analyse multivariee, l'utilisation d'agents d'induction antirejet (risque relatif [RR] 2,13, intervalle de confance [IC] de 95 % 1,05-4,35]), des receveurs de race blanche (RR 1,84, IC de 95 % 1,08-3,12), l'utilisation de greffons renaux provenant de donneurs a criteres elargis (RR 2,13, IC de 95 % 1,05-4,32) et un indice de masse corporel (IMC) moindre chez les receveurs (RR 0,95, IC de 95 % 0,91-1,00) ont fait augmenter le risque de TVP precoce. La prophylaxie anti-TVP entourant l'intervention n'a pas ete associee a la TVP precoce. La TVP precoce n'a pas ete associee a une diminution du fonctionnement du greffon, au deces, a la defaillance du greffon, ni a la premiere rehospitalisation. Conclusion : Dans notre cohorte de greffes du rein, les facteurs de risque de TVP precoce incluaient race blanche des receveurs, utilisation d'agents antirejet, IMC moindre des receveurs et donneurs a criteres elargis. A mesure qu'evolueront les principes de selection des donneurs et des receveurs pour la transplantation renale, les resultats de cette etude pourraient aider a evaluer le risque peri-operatoire et a eclairer les prises de decision entourant la prophylaxie anti-TVP., Kidney transplantation is the treatment of choice for end-stage renal disease, offering recipients improved survival and quality of life compared with dialysis. However, kidney transplant recipients (KTRs) are 7 to [...]

Background With improved survival among children after transplantation, our understanding of the risk for developing other comorbidities is improving, yet little is known about the long-term risk of cardiovascular events and mortality after solid organ transplantation. Methods In a cohort study using health administrative data, we compared cardiovascular events in children (n = 615) with liver, lung, kidney, small bowel, or multi-organ transplant at the Hospital for Sick Children, Toronto, Canada, with asthmatic children (n = 481,697) between 1996 and 2014. Outcomes included non-fatal cardiovascular events, cardiovascular death, all-cause mortality, and a composite of non-fatal and fatal cardiovascular events. Time-stratified Cox proportional hazards models were used. Results Among 615 children, 317 (52%) were recipients of kidneys, 253 (41%) of livers, and the remaining 45 (7%) had lung, small bowel, or multi-organ transplants. Median follow-up was 12.1 [7.2, 16.7] years. Non-fatal incident cardiovascular events were 34 times higher among solid organ transplant recipients than non-transplanted children (incidence rate ratio (IRR) 34.4, 95% CI: 25.5, 46.4). Among transplant recipients, the cumulative incidence of non-fatal and fatal cardiovascular events was 2.3% and 13.0%, 5 and 15 years after transplantation, respectively. Conclusions Increased rate of cardiovascular events in children after transplantation highlights the need for surveillance during transition into adulthood and beyond. Graphical abstract A higher resolution version of the Graphical abstract is available as Supplementary information., Author(s): Sandeep Brar [sup.1] [sup.2] , Stephanie N. Dixon [sup.3] [sup.4] [sup.5] , J. Michael Paterson [sup.6] [sup.7] , Jade Dirk [sup.3] [sup.4] , Emma Hahn [sup.3] [sup.4] , S. [...]

Kidney transplant ultrasonography is an important diagnostic tool in the care of transplant recipients. This modality of nonradiation‐based imaging allows for precise and expedient reporting of allograft architecture, which can inform clinical decision‐making. However, as with any diagnostic tool, overuse may lead to unnecessary interventions and costs on the healthcare system. To better understand the use of ultrasonography in hospitalized kidney transplant recipients and outcomes of subsequent interventions, we conducted a single‐center retrospective study at a large transplant program in Ontario, Canada. We noted that over 30% of admissions resulted in a ultrasonographic survey within the first 24 h of presentation; however, most of these did not change clinical management or lead to a subsequent procedural intervention. Using multivariable logistic regression, we identified predictors for receiving an ultrasound, including time from transplantation, elevated serum creatinine and infectious diagnosis. Procedural interventions (e.g., drain or biopsy) resulted from less than 20% of all ultrasound investigations, with patients closer to the time of index transplant or with elevated serum creatinine values more likely to receive an intervention. In conducting a cost analysis, we estimated that approximately $80 000 CAD per year could be saved with more selective decisions on ultrasound requisitions. Overall, our results indicate that despite being an informative tool, the broad use of ultrasonography in the kidney transplant population may not yield significant changes to transplant care. [ABSTRACT FROM AUTHOR]

Rationale & objectiveCardiovascular disease (CVD) is common and overall graft survival is suboptimal among kidney transplant recipients. Although albuminuria is a known risk factor for adverse outcomes among persons with native chronic kidney disease, the relationship of albuminuria with cardiovascular and kidney outcomes in transplant recipients is uncertain.Study designPost hoc longitudinal cohort analysis of the Folic Acid for Vascular Outcomes Reduction in Transplantation (FAVORIT) Trial.Setting & participantsStable kidney transplant recipients with elevated homocysteine levels from 30 sites in the United States, Canada, and Brazil.PredictorUrine albumin-creatinine ratio (ACR) at randomization.OutcomesAllograft failure, CVD, and all-cause death.Analytical approachMultivariable Cox models adjusted for age; sex; race; randomized treatment allocation; country; systolic and diastolic blood pressure; history of CVD, diabetes, and hypertension; smoking; cholesterol; body mass index; estimated glomerular filtration rate (eGFR); donor type; transplant vintage; medications; and immunosuppression.ResultsAmong 3,511 participants with complete data, median ACR was 24 (Q1-Q3, 9-98) mg/g, mean eGFR was 49±18 (standard deviation) mL/min/1.73m2, mean age was 52±9 years, and median graft vintage was 4.1 (Q1-Q3, 1.7-7.4) years. There were 1,017 (29%) with ACR < 10mg/g, 912 (26%) with ACR of 10 to 29mg/g, 1,134 (32%) with ACR of 30 to 299mg/g, and 448 (13%) with ACR ≥ 300mg/g. During approximately 4 years, 282 allograft failure events, 497 CVD events, and 407 deaths occurred. Event rates were higher at both lower eGFRs and higher ACR. ACR of 30 to 299 and ≥300mg/g relative to ACR < 10mg/g were independently associated with graft failure (HRs of 3.40 [95% CI, 2.19-5.30] and 9.96 [95% CI, 6.35-15.62], respectively), CVD events (HRs of 1.25 [95% CI, 0.96-1.61] and 1.55 [95% CI, 1.13-2.11], respectively), and all-cause death (HRs of 1.65 [95% CI, 1.23-2.21] and 2.07 [95% CI, 1.46-2.94], respectively).LimitationsNo data for rejection; single ACR assessment.ConclusionsIn a large population of stable kidney transplant recipients, elevated baseline ACR is independently associated with allograft failure, CVD, and death. Future studies are needed to evaluate whether reducing albuminuria improves these outcomes.

BackgroundUromodulin is a kidney-derived glycoprotein and putative tubular function index. Lower serum uromodulin was recently associated with increased risk for kidney allograft failure in a preliminary, longitudinal single-center -European study involving 91 kidney transplant recipients (KTRs).MethodsThe Folic Acid for Vascular Outcome Reduction in Transplantation (FAVORIT) trial is a completed, large, multiethnic controlled clinical trial cohort, which studied chronic, stable KTRs. We conducted a case cohort analysis using a randomly selected subset of patients (random subcohort, n = 433), and all individuals who developed kidney allograft failure (cases, n = 226) during follow-up. Serum uromodulin was determined in this total of n = 613 FAVORIT trial participants at randomization. Death-censored kidney allograft failure was the study outcome.ResultsThe 226 kidney allograft failures occurred during a median surveillance of 3.2 years. Unadjusted, weighted Cox proportional hazards modeling revealed that lower serum uromodulin, tertile 1 vs. tertile 3, was associated with a threefold greater risk for kidney allograft failure (hazards ratio [HR], 95% CI 3.20 [2.05-5.01]). This association was attenuated but persisted at twofold greater risk for allograft failure, after adjustment for age, sex, smoking, allograft type and vintage, prevalent diabetes mellitus and cardiovascular disease (CVD), total/high-density lipoprotein cholesterol ratio, systolic blood pressure, estimated glomerular filtration rate, and natural log urinary albumin/creatinine: HR 2.00, 95% CI (1.06-3.77).ConclusionsLower serum uromodulin, a possible indicator of less well-preserved renal tubular function, remained associated with greater risk for kidney allograft failure, after adjustment for major, established clinical kidney allograft failure and CVD risk factors, in a large, multiethnic cohort of long-term, stable KTRs.

Background: Surgical site complications (SSCs) are an important source of morbidity after kidney transplantation. We assessed the incidence, risk factors, outcomes and economic impact of SSCs in a large, diverse population of kidney transplant recipients. Methods: We conducted a single-centre, observational cohort study of adult (age [greater than or equal to] 18 yr) patients who underwent kidney transplantation between Jan. 1, 2005, and Dec. 31, 2015, with a minimum of 1 year of follow-up. Cases of SSC, including infections and wound dehiscence, were determined from patient records. Inpatient and outpatient hospital costs were determined 6 and 12 months after transplantation. We used the Kaplan-Meier product-limit method to determine the cumulative probability of SSCs and other outcomes. We evaluated risk factors and clinical outcomes using Cox proportional hazard ratios. Linear regression models were used to study the effect of SSCs on graft function. Results: The incidence rate of SSCs within 30 days after transplantation was 4.19 per 100 person-months. The cumulative probability of developing an SSC within 30 days after transplantation was 4.13% (95% confidence interval [CI] 3.23%-5.28%). Increased recipient body mass index (BMI) (hazard ratio [HR] 1.07, 95% CI 1.02-1.11), longer cold ischemic time (HR 1.05, 95% CI 1.01-1.09) and transplantation in 2010-2012 versus 2005-2009 (HR 2.20, 95% CI 1.19-4.04) were risk factors for SSC development. In multivariable stepwise Cox proportional hazard models, SSC was a significant risk factor for death-censored graft failure (HR 3.08, 95% CI 1.60-5.90) and total graft failure (HR 2.09, 95% CI 1.32-3.32). Cumulative median hospital costs were $22 38.46 greater for patients with an SSC than for those without. Conclusion: Increased BMI, longer cold ischemic time and the 2010-2012 transplantation period predisposed to SSCs. The development of SSCs was associated with a higher risk of graft failure. Strategies to minimize SSCs may improve outcomes after kidney transplantation and reduce costs. Contexte : Les complications affectant le site opératoire (CSO) sont une importante cause de morbidité après la transplantation rénale. Nous avons évalué l'incidence, les facteurs de risque, les résultats et l'impact économique des CSO auprès d'une volumineuse population hétérogène de receveurs de transplantations rénales. Méthodes : Nous avons procédé à une étude de cohorte d'observation monocentrique regroupant des patients adultes (âge [greater than or equal to] 18 ans) soumis à une transplantation rénale entre le 1er janvier 2005 et le 31 décembre 2015, et suivis pendant au moins 1 an. Les cas de CSO, incluant les infections et les déhiscences de plaies ont été confirmés à partir des dossiers des patients. Le coût des hospitalisations et des soins ambulatoires a été calculé 6 et 12 mois après la transplantation. Nous avons utilisé l'estimateur de produit-limite de Kaplan-Meier pour établir la probabilité cumulative de CSO et d'autres paramètres. Nous avons évalué les facteurs de risque et les paramètres cliniques par la méthode des risques proportionnels de Cox. Des modèles de régression linéaire ont servi à l'analyse de l'impact des CSO sur le fonctionnement des greffons. Résultats : Le taux d'incidence des CSO dans les 30 jours suivant la transplantation a été de 4,19 par 100 mois-personnes. La probabilité cumulative d'une CSO dans les 30 jours suivant la transplantation a été de 4,13% (intervalle de confiance [IC] de 95% 3,23%-5,28%). Les facteurs de risque de CSO étaient indice de masse corporelle (IMC) élevé (risque relatif [RR] 1,07, IC de 95% 1,02-1,11), durée plus longue de l'ischémie froide (RR 1,05, IC de 95% 1,01-1,09) et transplantation effectuée en 2010-2012 c. 2005-2009 (RR 2,20, IC de 95% 1,19-4,04). Dans les modèles à risques proportionnels de Cox multivariés séquentiels, les CSO ont été d'importants facteurs de risque d'échec du greffon après censure des décès survenus avec des greffons fonctionnels (RR 3,08, IC de 95% 1,60-5,90) et d'échec total du greffon (RR 2,09, IC de 95% 1,32-3,32). Les coûts hospitaliers médians cumulatifs ont été de 2238,46 $ de plus chez les patients ayant connu une CSO par rapport aux patients indemnes de CSO. Conclusion : Un IMC élevé, une durée plus longue de l'ischémie froide et la transplantation effectuée entre 2010 et 2012 ont prédisposé les patients à des CSO. Les CSO ont été associées à un risque plus grand d'échec du greffon. Les stratégies visant à prévenir les CSO pourraient améliorer les résultats de la transplantation rénale et en réduire les coûts., Kidney transplantation is the preferred treatment for end-stage renal disease, offering enhanced survival and quality of life as compared to dialysis. However, surgical site complications (SSCs) represent an important source [...]

BackgroundWe examined if African or Asian ethnicity was associated with lower access to kidney transplantation (KT) in a Canadian setting.MethodsPatients referred for KT to the Toronto General Hospital from January 1, 2003, to December 31, 2012, who completed social work assessment, were included (n = 1769). The association between ethnicity and the time from referral to completion of KT evaluation or receipt of a KT were examined using Cox proportional hazards models.ResultsAbout 54% of the sample was white, 13% African, 11% East Asian, and 11% South Asian; 7% had "other" (n = 121) ethnic background. African Canadians (hazard ratio [HR], 0.75; 95% CI: 0.62-0.92]) and patients with "other" ethnicity (HR, 0.71; 95% CI, 0.55-0.92) were less likely to complete the KT evaluation compared with white Canadians, and this association remained statistically significant in multivariable adjusted models. Access to KT was significantly reduced for all ethnic groups assessed compared with white Canadians, and this was primarily driven by differences in access to living donor KT. The adjusted HRs for living donor KT were 0.35 (95% CI, 0.24-0.51), 0.27 (95% CI, 0.17-0.41), 0.43 (95% CI, 0.30-0.61), and 0.34 (95% CI, 0.20-0.56) for African, East or South Asian Canadians and for patients with "other" ethnic background, respectively.ConclusionsSimilar to other jurisdictions, nonwhite patients face barriers to accessing KT in Canada. This inequity is very substantial for living donor KT. Further research is needed to identify if these inequities are due to potentially modifiable barriers.

Background: Intraoperative hypotension is associated with acute kidney injury after surgery. However, the definition (duration and magnitude) of hypotension during kidney transplantation (KT) surgery on early graft function remains unclear. Methods: We conducted a retrospective cohort study of KT recipients from December 1, 2009, to December 31, 2019. Exposure to intraoperative hypotension was characterized as the duration (minutes) of mean arterial pressure (MAP) <55, <65, <75, and <85 mmHg. Our co‐primary outcomes were DGF‐creatinine reduction ratio (DGF‐CRR, <30% creatinine reduction, postoperative days 1 and 2), and DGF‐dialysis (DGF‐D, required dialysis within the week of KT for deceased donor recipients). Logistic regression models were fitted to assess this relationship between MAP and DGF. Results: We included 1602 KT (939 deceased donors, 663 living donors) and 23 were excluded. DGF‐CRR occurred in 33% of patients. DGF‐CRR was associated with MAP < 65 (>5 min: OR 1.77, 95% confidence interval [CI]: 1.39–2.30; 6–10 min: OR 1.67, 95% CI: 0.97–2.86; 11–20 min: OR 2.18, 95% CI: 1.31–3.63) in unadjusted and <55 mmHg (5 min: OR 1.85, 95% CI: 1.47–2.32; 5–10 min: OR 2.41, 95% CI: 1.65–3.53; 11–20 min: OR 2.36, 95% CI: 1.60, 3.48) in adjusted models. There was also a signal for increased risk of DGF‐CRR at MAP < 75 (>5 min: OR 1.69, 95% CI: 1.02–2.80). DGF‐D (incidence 35%) in deceased donor KT was not associated with hypotension. Conclusions: We found an association between intraoperative hypotension and DGF‐CRR at a threshold MAP of 55 mmHg, with a consistent signal toward increased risk at both 65 and 75 mmHg, as indicated by unadjusted models. [ABSTRACT FROM AUTHOR]

BackgroundFew reports have shown an association between access type and inflammatory marker levels in a longitudinal cohort. We investigated the role of access type on serial levels of inflammatory markers and the role of inflammatory markers in mediating the association of access type and risk of mortality in a prospective study of incident dialysis patients.Study designCohort study, post hoc analysis of the CHOICE (Choices for Healthy Outcomes in Caring for ESRD) Study.Setting & participantsIn 583 participants, inflammation was assessed by measuring serum C-reactive protein (CRP) and interleukin 6 (IL-6) after access placement and at multiple times during 3 years' follow-up. Type of access was categorized as central venous catheter (CVC), arteriovenous graft (AVG), and arteriovenous fistula (AVF), and changes over time were recorded.PredictorAccess type, age, sex, race, body mass index, diabetes, cardiovascular disease, and serum albumin level.OutcomesCRP level, IL-6 level, and mortality.MeasurementsWe used mixed-effects pattern mixture models to study the association between access type and repeated measurements of inflammation and survival analysis to investigate the association of access type and mortality, adjusting for predictors.ResultsIn a mixed-effects pattern mixture model, compared with AVFs, the presence of CVCs and AVGs was associated with 62% (P=0.02) and 30% (P=0.05) increases in average CRP levels, respectively. A Cox proportional hazards model yielded nonsignificant associations of CVC and AVG use (vs AVFs) with risk of mortality when adjusted for inflammatory marker levels. Higher CRP levels were associated with increased risk of CVC failure than lower CRP levels.LimitationsCRP and IL-6 measurements not performed for all hemodialysis patients.ConclusionsCVCs, compared with AVFs, are associated with a greater state of inflammation in incident hemodialysis patients, and the association of catheter use and mortality may be mediated by access-induced inflammation. Our findings support recommendations for the early removal or avoidance of CVC placements.

Although the United States possesses one of the most comprehensive transplant registries in the world, nationally representative data on how transplant care is structured and delivered is lacking. Therefore, we surveyed all 208 adult kidney transplant centers in the United States, excluding 37 pediatric and 58 inactive adult centers. Respondents were asked about the characteristics of their kidney transplant programs (25 items), the structure and process of care (18 items), coordination of care (10 items), and the characteristics of transplant physicians and surgeons (9 items). The survey was completed by directors of 156 transplant centers (75% response). The results demonstrated significant variation between centers in several domains. Sixty-five percent of transplant centers do not have a dedicated transplant pharmacist in outpatient care. Two thirds of transplant centers do not see the kidney transplant recipients at least monthly during the first year. Less than 30% of centers perform joint sit-down or walking rounds between nephrology and transplant surgery. There was significant variation in the structure and process of care in kidney transplantation. This implies variation in the use of resources at the transplant centers. This variation should be studied to determine best practices associated with optimal kidney allograft and patient survival.

Background Mental health problems, particularly anxiety and depression, are common in patients with chronic kidney disease (CKD) and negatively impact quality of life, treatment adherence and mortality. However, the degree to which mental health and addiction services are utilized by those with CKD is unknown. We examined the history of mental health and addiction service use of individuals across levels of kidney function. Methods We performed a population-based cross-sectional study using linked healthcare databases from Ontario, Canada from 2009 to 2017. We abstracted the prevalence of individuals with mental health and addiction service use within the previous 3 years across levels of kidney function [estimated glomerular filtration rate (eGFR) ≥60, 45 to <60, 30 to <45, 15 to <30, <15 ml/min/1.73 m2 and maintenance dialysis]. We calculated prevalence ratios (PRs) to compare prevalence across kidney function strata, while adjusting for age, sex, year of cohort entry, urban versus rural location, area-level marginalization and Charlson comorbidity index. Results Of 5 956 589 adults, 9% (n  = 534 605) had an eGFR <60 ml/min/1.73 m2 or were receiving maintenance dialysis. Fewer individuals with an eGFR <60 ml/min/1.73 m2 had a history of any mental health and addiction service utilization (crude prevalence range 28–31%) compared with individuals with an eGFR ≥60 ml/min/1.73 m2 (35%). Compared with an eGFR ≥60 ml/min/1.73 m2, the lowest prevalence of individuals with any mental health and addiction service utilization was among those with an eGFR of 15 to <30 ml/min/1.73 m2 {adjusted PR 0.86 [95% confidence interval (CI) 0.85 to 0.88]}, an eGFR <15 ml/min/1.73 m2 [adjusted PR 0.81 (95% CI 0.76–0.86)] and those receiving maintenance dialysis [adjusted PR 0.83 (95% CI 0.81–0.84)]. Less use of outpatient services accounted for differences in service utilization. Conclusions Mental health and addiction service utilization is common but less so in individuals with advanced CKD in Ontario, Canada. [ABSTRACT FROM AUTHOR]

In the last decade, the number of patients starting dialysis after a failed kidney transplant has increased substantially. These patients appear to be different from their transplant-naïve counterparts, and so may be the timing of dialysis therapy initiation. An increasing number of studies suggest that in transplant-naïve patients, later dialysis initiation is associated with better outcomes. Very few data are available on timing of dialysis reinitiation in failed transplant recipients, and they suggest that an earlier return to dialysis therapy tended to be associated with worse survival, especially among healthier and younger patients and women. Failed transplant patients may also have unique issues such as continuation of immunosuppression versus withdrawal or the need for remnant allograft nephrectomy with regard to dialysis reinitiation. These patients may have a different predialysis preparation work-up, worse blood pressure control, higher or lower serum phosphorus levels, lower serum bicarbonate concentration, and worse anemia management. The choice of dialysis modality may also represent an important question for these patients, even though there appears to be no difference in mortality between patients starting peritoneal versus hemodialysis. Finally, failed transplant patients returning to dialysis appear to have a higher mortality rate compared with transplant-naïve incident dialysis patients, especially in the first several months of dialysis therapy. In this review, we will summarize the available data related to the timing of dialysis initiation and outcomes in failed kidney transplant patients after returning to dialysis.