Ten-year trends in epidemiology and outcomes of pediatric kidney replacement therapy in Europe: data from the ESPN/ERA-EDTA Registry.

BACKGROUND: For 10 consecutive years, the ESPN/ERA-EDTA Registry has included data on children with stage 5 chronic kidney disease (CKD 5) receiving kidney replacement therapy (KRT) in Europe. We examined trends in incidence and prevalence of KRT and patient survival. METHODS: We included all children aged <15 years starting KRT 2007-2016 in 22 European countries participating in the ESPN/ERA-EDTA Registry since 2007. General population statistics were derived from Eurostat. Incidence and prevalence were expressed per million age-related population (pmarp) and time trends studied with JoinPoint regression. We analyzed survival trends using Cox regression. RESULTS: Incidence of children commencing KRT <15 years remained stable over the study period, varying between 5.5 and 6.6 pmarp. Incidence by treatment modality was unchanged over time: 2.0 for hemodialysis (HD) and peritoneal dialysis (PD) and 1.0 for transplantation. Prevalence increased in all age categories and overall rose 2% annually from 26.4 pmarp in 2007 to 32.1 pmarp in 2016. Kidney transplantation prevalence increased 5.1% annually 2007-2009, followed by 1.5% increase/year until 2016. Prevalence of PD steadily increased 1.4% per year over the entire period, and HD prevalence started increasing 6.1% per year from 2011 onwards. Five-year unadjusted patient survival on KRT was around 94% and similar for those initiating KRT 2007-2009 or 2010-2012 (adjusted HR: 0.98, 95% CI:0.71-1.35). CONCLUSIONS: We found a stable incidence and increasing prevalence of European children on KRT 2007-2016. Five-year patient survival was good and was unchanged over time. These data can inform patients and healthcare providers and aid health policy makers on future resource planning of pediatric KRT in Europe.

Survival of patients treated with extended-hours haemodialysis in Europe: an analysis of the ERA-EDTA Registry.

BACKGROUND: Previous US studies have indicated that haemodialysis with ≥6-h sessions [extended-hours haemodialysis (EHD)] may improve patient survival. However, patient characteristics and treatment practices vary between the USA and Europe. We therefore investigated the effect of EHD three times weekly on survival compared with conventional haemodialysis (CHD) among European patients. METHODS: We included patients who were treated with haemodialysis between 2010 and 2017 from eight countries providing data to the European Renal Association-European Dialysis and Transplant Association Registry. Haemodialysis session duration and frequency were recorded once every year or at every change of haemodialysis prescription and were categorized into three groups: CHD (three times weekly, 3.5-4 h/treatment), EHD (three times weekly, ≥6 h/treatment) or other. In the primary analyses we attributed death to the treatment at the time of death and in secondary analyses to EHD if ever initiated. We compared mortality risk for EHD to CHD with causal inference from marginal structural models, using Cox proportional hazards models weighted for the inverse probability of treatment and censoring and adjusted for potential confounders. RESULTS: From a total of 142 460 patients, 1338 patients were ever treated with EHD (three times, 7.1 ± 0.8 h/week) and 89 819 patients were treated exclusively with CHD (three times, 3.9 ± 0.2 h/week). Crude mortality rates were 6.0 and 13.5/100 person-years. In the primary analyses, patients treated with EHD had an adjusted hazard ratio (HR) of 0.73 [95% confidence interval (CI) 0.62-0.85] compared with patients treated with CHD. When we attributed all deaths to EHD after initiation, the HR for EHD was comparable to the primary analyses [HR 0.80 (95% CI 0.71-0.90)]. CONCLUSIONS: EHD is associated with better survival in European patients treated with haemodialysis three times weekly.

Young deceased donor kidneys show a survival benefit over older donor kidneys in transplant recipients aged 20-50 years: a study by the ERA-EDTA Registry.

BACKGROUND: Updated survival outcomes of young recipients receiving young or old deceased donor kidneys are required when considering accepting a deceased donor kidney. METHODS: We examined outcomes in 6448 European kidney allografts donated from younger (≥20-<50 years) and older (≥50-<70 years) deceased donors when transplanted into very young (≥20-<35 years) or young (≥35-<50 years) adult recipients. Outcomes of first kidney transplantations during 2000-13 and followed-up to 2015 were determined via competing risk, restricted mean survival and Cox regression methods. RESULTS: The 10-year cumulative incidence of graft failure was lowest in very young {22.0% [95% confidence interval (95% CI) 19.1-24.9]} and young [15.3% (95% CI 13.7-16.9)] recipients of younger donor kidneys and highest in very young [36.7% (95% CI 31.9-41.5)] and young [29.2% (95% CI 25.1-33.2)] recipients of older donor kidneys. At the 10-year follow-up, younger donor kidneys had a 1 year (very young) or 9 months (young) longer mean graft survival time compared with older donor kidneys. Graft failure risk in younger donor kidneys was 45% [very young adjusted hazard ratio (aHR) 0.55 (95% CI 0.44-0.68)] and 40% [young aHR 0.60 (95% CI 0.53-0.67)] lower compared with older donor kidneys. A 1-year increase in donor age resulted in a 2% [very young aHR 1.02 (95% CI 1.00-1.04)] or 1% [young aHR 1.01 (95% CI 1.00-1.01)] increase in the 10-year risk of death. CONCLUSIONS: Younger donor kidneys show survival benefits over older donor kidneys in adult recipients ages 20-50 years. Updated survival outcomes from older deceased donors are necessary due to advances in transplantation medicine and the increasing role these donors play in organ transplantation.

Infants Requiring Maintenance Dialysis: Outcomes of Hemodialysis and Peritoneal Dialysis.

BACKGROUND: The impact of different dialysis modalities on clinical outcomes has not been explored in young infants with chronic kidney failure. STUDY DESIGN: Cohort study. SETTING & PARTICIPANTS: Data were extracted from the ESPN/ERA-EDTA Registry. This analysis included 1,063 infants 12 months or younger who initiated dialysis therapy in 1991 to 2013. FACTOR: Type of dialysis modality. OUTCOMES & MEASUREMENTS: Differences between infants treated with peritoneal dialysis (PD) or hemodialysis (HD) in patient survival, technique survival, and access to kidney transplantation were examined using Cox regression analysis while adjusting for age at dialysis therapy initiation, sex, underlying kidney disease, and country of residence. RESULTS: 917 infants initiated dialysis therapy on PD, and 146, on HD. Median age at dialysis therapy initiation was 4.5 (IQR, 0.7-7.9) months, and median body weight was 5.7 (IQR, 3.7-7.5) kg. Although the groups were homogeneous regarding age and sex, infants treated with PD more often had congenital anomalies of the kidney and urinary tract (CAKUT; 48% vs 27%), whereas those on HD therapy more frequently had metabolic disorders (12% vs 4%). Risk factors for death were younger age at dialysis therapy initiation (HR per each 1-month later initiation, 0.95; 95% CI, 0.90-0.97) and non-CAKUT cause of chronic kidney failure (HR, 1.49; 95% CI, 1.08-2.04). Mortality risk and likelihood of transplantation were equal in PD and HD patients, whereas HD patients had a higher risk for changing dialysis treatment (adjusted HR, 1.64; 95% CI, 1.17-2.31). LIMITATIONS: Inability to control for unmeasured confounders not included in the Registry database and missing data (ie, comorbid conditions). Low statistical power because of relatively small number of participants. CONCLUSIONS: Despite a widespread preconception that HD should be reserved for cases in which PD is not feasible, in Europe, we found 1 in 8 infants in need of maintenance dialysis to be initiated on HD therapy. Patient characteristics at dialysis therapy initiation, prospective survival, and time to transplantation were very similar for infants initiated on PD or HD therapy.

Kidney Versus Combined Kidney and Liver Transplantation in Young People With Autosomal Recessive Polycystic Kidney Disease: Data From the European Society for Pediatric Nephrology/European Renal Association-European Dialysis and Transplant (ESPN/ERA-EDTA) Registry.

BACKGROUND: The choice for either kidney or combined liver-kidney transplantation in young people with kidney failure and liver fibrosis due to autosomal recessive polycystic kidney disease (ARPKD) can be challenging. We aimed to analyze the characteristics and outcomes of transplantation type in these children, adolescents, and young adults. STUDY DESIGN: Cohort study. SETTING & PARTICIPANTS: We derived data for children, adolescents, and young adults with ARPKD with either kidney or combined liver-kidney transplants for 1995 to 2012 from the ESPN/ERA-EDTA Registry, a European pediatric renal registry collecting data from 36 European countries. FACTOR: Liver transplantation. OUTCOMES & MEASUREMENTS: Transplantation and patient survival. RESULTS: 202 patients with ARPKD aged 19 years or younger underwent transplantation after a median of 0.4 (IQR, 0.0-1.4) years on dialysis therapy at a median age of 9.0 (IQR, 4.1-13.7) years. 32 (15.8%) underwent combined liver-kidney transplantation, 163 (80.7%) underwent kidney transplantation, and 7 (3.5%) were excluded because transplantation type was unknown. Age- and sex-adjusted 5-year patient survival posttransplantation was 95.5% (95% CI, 92.4%-98.8%) overall: 97.4% (95% CI, 94.9%-100.0%) for patients with kidney transplantation in contrast to 87.0% (95% CI, 75.8%-99.8%) with combined liver-kidney transplantation. The age- and sex-adjusted risk for death after combined liver-kidney transplantation was 6.7-fold (95% CI, 1.8- to 25.4-fold) greater than after kidney transplantation (P=0.005). Five-year death-censored kidney transplant survival following combined liver-kidney and kidney transplantation was similar (92.1% vs 85.9%; P=0.4). LIMITATIONS: No data for liver disease of kidney therapy recipients. CONCLUSIONS: Combined liver-kidney transplantation in ARPKD is associated with increased mortality compared to kidney transplantation in our large observational study and was not associated with improved 5-year kidney transplant survival. Long-term follow-up of both kidney and liver involvement are needed to better delineate the optimal transplantation strategy.

Lessons learned from the ESPN/ERA-EDTA Registry.

End-stage renal disease (ESRD) in children is a medically challenging condition. Due to its rarity and special features, methodologically sound collaborative studies are required. In 2007, a new European registry of pediatric renal replacement therapy (RRT), the ESPN/ERA-EDTA Registry, was launched. In recent years, the Registry has provided comprehensive data on incidence, prevalence, patient characteristics, RRT modalities, and mortality in pediatric ESRD, along with relevant insights into cardiovascular risk, anemia, nutrition and growth, transplantation outcomes, and rare diseases. In this review, we describe the study design and structure underlying the ESPN/ERA-EDTA Registry, summarize the major research findings from more than 20 publications, and discuss current limitations and the future challenges to overcome.