Outcomes of early hospital readmission after kidney transplantation: Perspectives from a Canadian transplant centre.

BACKGROUND: Early hospital readmissions (EHRs) after kidney transplantation range in incidence from 18%-47% and are important and substantial healthcare quality indicators. EHR can adversely impact clinical outcomes such as graft function and patient mortality as well as healthcare costs. EHRs have been extensively studied in American healthcare systems, but these associations have not been explored within a Canadian setting. Due to significant differences in the delivery of healthcare and patient outcomes, results from American studies cannot be readily applicable to Canadian populations. A better understanding of EHR can facilitate improved discharge planning and long-term outpatient management post kidney transplant. AIM: To explore the burden of EHR on kidney transplant recipients (KTRs) and the Canadian healthcare system in a large transplant centre. METHODS: This single centre cohort study included 1564 KTRs recruited from January 1, 2009 to December 31, 2017, with a 1-year follow-up. We defined EHR as hospitalizations within 30 d or 90 d of transplant discharge, excluding elective procedures. Multivariable Cox and linear regression models were used to examine EHR, late hospital readmissions (defined as hospitalizations within 31-365 d for 30-d EHR and within 91-365 d for 90-d EHR), and outcomes including graft function and patient mortality. RESULTS: In this study, 307 (22.4%) and 394 (29.6%) KTRs had 30-d and 90-d EHRs, respectively. Factors such as having previous cases of rejection, being transplanted in more recent years, having a longer duration of dialysis pretransplant, and having an expanded criteria donor were associated with EHR post-transplant. The cumulative probability of death censored graft failure, as well as total graft failure, was higher among the 90-d EHR group as compared to patients with no EHR. While multivariable models found no significant association between EHR and patient mortality, patients with EHR were at an increased risk of late hospital readmissions, poorer kidney function throughout the 1st year post-transplant, and higher hospital-based care costs within the 1st year of follow-up. CONCLUSION: EHRs are associated with suboptimal outcomes after kidney transplant and increased financial burden on the healthcare system. The results warrant the need for effective strategies to reduce post-transplant EHR.

Time-Varying Proteinuria and the Risk of Cardiovascular Disease and Graft Failure in Kidney Transplant Recipients.

Introduction: Proteinuria is recognized as an independent risk factor for cardiovascular disease in kidney transplant recipients, but previous studies have not considered the impact of changes in urine protein over time. Research Question and Design: We used time-dependent, multivariable Cox proportional hazards models in this observational cohort study of adult kidney transplant recipients to evaluate whether proteinuria measured by dipstick on random spot urine samples starting from 1-month post-transplant was associated with the risk of major adverse cardiac events and graft loss. Results: A total of 144 major adverse cardiac events, defined as acute myocardial infarction, cerebrovascular accident, revascularization, or all-cause mortality, were observed in 1106 patients over 5728.7 person-years. Any level of proteinuria greater or equal to trace resulted in a two-fold increase in the risk of major adverse cardiac events (hazard ratio 2.00 [95% confidence interval 1.41, 2.84]). This relationship was not found to be dose-dependent (hazard ratios of 2.98, 1.76, 1.63, and 1.54 for trace, 1+, 2+, and 3+ urine protein, respectively). There was an increased risk of graft failure with greater urine protein concentration (hazard ratios 2.22, 2.85, 6.41, and 19.71 for trace, 1+, 2+, and 3+, respectively). Conclusion: Urine protein is associated with major adverse cardiac events and graft loss in kidney transplant recipients. The role of interventions to reduce proteinuria on decreasing the risk of adverse cardiovascular and graft outcomes in kidney transplant recipients requires further study.

Use of the Living Kidney Donor Profile Index in the Canadian Kidney Transplant Recipient Population: A Validation Study.

BACKGROUND: The Living Kidney Donor Profile Index (LKDPI) was derived in a cohort of kidney transplant recipients (KTR) from the United States to predict the risk of total graft failure. There are important differences in patient demographics, listing practices, access to transplantation, delivery of care, and posttransplant mortality in Canada as compared with the United States, and the generalizability of the LKDPI in the Canadian context is unknown. OBJECTIVE: The purpose of this study was to externally validate the LKDPI in a large contemporary cohort of Canadian KTR. DESIGN: Retrospective cohort validation study. SETTING: Toronto General Hospital, University Health Network, Toronto, Ontario, Canada. PATIENTS: A total of 645 adult (≥18 years old) living donor KTR between January 1, 2006 and December 31, 2016 with follow-up until December 31, 2017 were included in the study. MEASUREMENTS: The predictive performance of the LKDPI was evaluated. The outcome of interest was total graft failure, defined as the need for chronic dialysis, retransplantation, or death with graft function. METHODS: The Cox proportional hazards model was used to examine the relation between the LKDPI and total graft failure. The Cox proportional hazards model was also used for external validation and performance assessment of the model. Discrimination and calibration were used to assess model performance. Discrimination was assessed using Harrell's C statistic and calibration was assessed graphically, comparing observed versus predicted probabilities of total graft failure. RESULTS: A total of 645 living donor KTR were included in the study. The median LKDPI score was 13 (interquartile range [IQR] = 1.1, 29.9). Higher LKDPI scores were associated with an increased risk of total graft failure (hazard ratio = 1.01; 95% confidence interval [CI] = 1.0-1.02; P = .02). Discrimination was poor (C statistic = 0.55; 95% CI = 0.48-0.61). Calibration was as good at 1-year posttransplant but suboptimal at 3- and 5-years posttransplant. LIMITATIONS: Limitations include a relatively small sample size, predicted probabilities for assessment of calibration only available for scores of 0 to 100, and some missing data handled by imputation. CONCLUSIONS: In this external validation study, the predictive ability of the LKDPI was modest in a cohort of Canadian KTR. Validation of prediction models is an important step to assess performance in external populations. Potential recalibration of the LKDPI may be useful prior to clinical use in external cohorts.

CONTEXTE: L'indice Living Kidney Donor Profile Index (LKDPI) est employé pour prédire le risque de perte du greffon et dérive d'une cohorte de receveurs d'une greffe rénale (RGR) aux États-Unis. Il existe toutefois d'importantes différences entre le Canada et les États-Unis quant aux données démographiques des patients, aux pratiques relatives aux listes, à l'accès à une transplantation, à la prestation des soins et à la mortalité post-transplantation. La généralisation de l'indice LKDPI en contexte canadien demeure inconnue. OBJECTIF: L'objectif de cette étude était de valider l'indice LKDPI à l'externe, dans une vaste cohorte de RGR canadiens. TYPE D'ÉTUDE: Une étude de validité menée de façon rétrospective. CADRE: L'hôpital général de Toronto, membre du réseau universitaire de santé de Toronto (Ontario), Canada. SUJETS: Ont été inclus 645 adultes RGR provenant d'un donneur vivant entre le 1er janvier 2006 et le 31 décembre 2016 avec suivi s'étant poursuivi jusqu'au 31 décembre 2017. MESURES: La performance prédictive de l'indice LKDPI a été évaluée. Le principal résultat d'intérêt était la perte du greffon, telle que définie par le besoin de dialyse à vie, par une nouvelle transplantation ou par le décès du patient avec un greffon fonctionnel. MÉTHODOLOGIE: Un modèle des risques proportionnels de Cox a été employé pour quantifier la relation entre l'indice LKDPI et la perte du greffon. Le modèle des risques proportionnels de Cox a également servi à la validation externe et à la mesure de la performance du modèle prédictif. La discrimination et l'étalonnage ont été utilisés pour évaluer la performance du modèle. La discrimination a été mesurée à l'aide de la statistique c de Harrell et l'étalonnage a été évalué graphiquement en comparant les probabilités prévues et observées de perte du greffon. RÉSULTATS: Un total de 645 RGR provenant d'un donneur vivant ont été inclus. Le score médian de l'indice était de 13 (ÉIQ: 1,1; 29,9). Un score élevé pour l'indice LKDPI a été associé à un risque accru de perte du greffon [Rapport de risque : 1,01 (IC 95 % : 1,0; 1,02), P = 0,02]. La discrimination s'est avérée faible [statistique c : 0,55 (IC 95 % : 0,48; 0,61)], et l'étalonnage était bon un an après l'intervention, mais sous-optimal trois ans et cinq ans après la greffe. LIMITES: La taille de l'échantillon était relativement faible, les probabilités prévues utilisées pour évaluer l'étalonnage n'étaient disponibles que pour les scores entre 0 et 100, et certaines données manquantes ont été traitées par imputation. CONCLUSION: La valeur prédictive de l'indice LKDPI s'est avérée modeste dans la cohorte de RGR canadiens analysée pour cette étude de validité externe. La validation des modèles prédictifs est une étape essentielle pour évaluer leur performance dans des populations externes. Il conviendrait de réétalonner l'indice LKDPI avant son utilization clinique dans des cohortes externes.

A Gap Analysis Assessing the Perceptions of Primary Care Physicians in the Management of Kidney Recipients After Transplantation.

OBJECTIVES: To examine the practice patterns and perceptions of primary care physicians in the management of chronic diseases in kidney recipients, assess care provided to recipients, and identify barriers to the optimal delivery of primary care to recipients. METHODS: A self-administered questionnaire on the primary care of kidney recipients was developed and implemented. The survey investigated physician comfort and practice patterns in providing preventive and chronic care to recipients, patient self-management support, and physician perceptions on communication with transplant centers and barriers to ideal care. RESULTS: A total of 210 physicians completed the survey (response rate of 22%). Among the respondents, 73% indicated they were currently providing care to kidney recipients. The majority of physicians specified that they rarely (57%) or never (20%) communicate with transplant centers. Most physicians felt comfortable providing care to recipients for non-transplant-related issues (92.5%), vaccinations (85%), and periodic health examinations (94%). The majority (75.3%) of physicians felt uncomfortable managing the immunosuppressive medications of recipients. Physicians' most commonly stated barriers to delivering optimal care to recipients were insufficient guidelines provided by the transplant center (68.9%) and lack of knowledge in managing recipients (58.8%). Suggested resources by physicians to improve their comfort level in managing recipients included guidelines and continuing medical educational activities related to transplantation. CONCLUSIONS: Our results suggest that there are barriers to delivering optimal primary care to kidney recipients. The approach to providing resources needed to bridge the knowledge gap for physicians in the management of recipients requires further exploration.