The ERA Registry Annual Report 2021: a summary.

Background: The European Renal Association (ERA) Registry collects data on kidney replacement therapy (KRT) in patients with end-stage kidney disease (ESKD). This paper is a summary of the ERA Registry Annual Report 2021, including a comparison across treatment modalities. Methods: Data was collected from 54 national and regional registries from 36 countries, of which 35 registries from 18 countries contributed individual patient data and 19 registries from 19 countries contributed aggregated data. Using this data, incidence and prevalence of KRT, kidney transplantation rates, survival probabilities and expected remaining lifetimes were calculated. Result: In 2021, 533.2 million people in the general population were covered by the ERA Registry. The incidence of KRT was 145 per million population (pmp). In incident patients, 55% were 65 years or older, 64% were male, and the most common primary renal disease (PRD) was diabetes (22%). The prevalence of KRT was 1040 pmp. In prevalent patients, 47% were 65 years or older, 62% were male, and the most common PRDs were diabetes and glomerulonephritis/sclerosis (both 16%). On 31 December 2021, 56% of patients received haemodialysis, 5% received peritoneal dialysis, and 39% were living with a functioning graft. The kidney transplantation rate in 2021 was 37 pmp, a majority coming from deceased donors (66%). For patients initiating KRT between 2012-2016, 5-year survival probability was 52%. Compared to the general population, life expectancy was 65% and 68% shorter for males and females receiving dialysis, and 40% and 43% shorter for males and females living with a functioning graft.

A comparison of the epidemiology of kidney replacement therapy between Europe and the United States: 2021 data of the ERA Registry and the USRDS.

BACKGROUND AND HYPOTHESIS: This paper compares the most recent data on the incidence and prevalence of kidney replacement therapy (KRT), kidney transplantation rates, and mortality on KRT from Europe to those from the United States (US), including comparisons of treatment modalities (haemodialysis (HD), peritoneal dialysis (PD), and kidney transplantation (KTx)). METHODS: Data were derived from the annual reports of the European Renal Association (ERA) Registry and the United States Renal Data System (USRDS). The European data include information from national and regional renal registries providing the ERA Registry with individual patient data. Additional analyses were performed to present results for all participating European countries together. RESULTS: In 2021, the KRT incidence in the US (409.7 per million population (pmp)) was almost 3-fold higher than in Europe (144.4 pmp). Despite the substantial difference in KRT incidence, approximately the same proportion of patients initiated HD (Europe: 82%, US: 84%), PD (14%; 13% respectively), or underwent pre-emptive KTx (4%; 3% respectively). The KRT prevalence in the US (2436.1 pmp) was 2-fold higher than in Europe (1187.8 pmp). Within Europe, approximately half of all prevalent patients were living with a functioning graft (47%), while in the US, this was one third (32%). The number of kidney transplantations performed was almost twice as high in the US (77.0 pmp) compared to Europe (41.6 pmp). The mortality of patients receiving KRT was 1.6-fold higher in the US (157.3 per 1000 patient years) compared to Europe (98.7 per 1000 patient years). CONCLUSIONS: The US had a much higher KRT incidence, prevalence, and mortality compared to Europe, and despite a higher kidney transplantation rate, a lower proportion of prevalent patients with a functioning graft.

Twenty years of the French Renal Epidemiology and Information Network.

Background: The French Renal Epidemiology and Information Network (REIN) is 20 years old. It is not just a national data registry, but rather an epidemiological and informational network serving patients with chronic kidney disease, nephrology teams and health services. Methods: The past 10-year trends of the incidence and prevalence of renal replacement therapy by dialysis or kidney transplantation and waitlist activity are presented. To detect potential significant changes in trends from 2012 and 2021, a Joinpoint regression model was used. Results: The overall incidence of treated end-stage kidney disease (ESKD) was 169 per million population (pmp) in 2021. It was stable despite an increase in the incidence of diabetes. We found a decreasing trend in the proportion of patients starting dialysis in an emergency but an increase in those starting haemodialysis (HD) with a temporary catheter. Peritoneal dialysis decreased by 1.7% each year, whereas home HD, although involving only 1% of dialysis patients, increased by 10% each year. For patients not treated at home, the median time to drive from the patient's home to the dialysis unit was 17 min. The proportion of patients on the transplantation waitlist at the start of dialysis increased from 7% to 12%. Among the 111 263 new ESKD patients from 2012 to 2021, 8% received a first transplant at 1 year and 20% at 5 years. Among kidney transplant recipients, the mean time on the waitlist increased from 13.8 to 22.6 months. Living donor transplants increased in frequency, representing 15% of kidney transplants. Conclusions: Data from the REIN registry allow for the evaluation of needs and provide a planning tool for French authorities. The progressive implementation of automatic data retrieval from dialysis informatics charts might alleviate the burden of data collection. Furthermore, the research activity the REIN engenders, resulting in renewed confidence by health authorities in the dynamism of French nephrology, allows for an optimistic outlook for the REIN.

The ERA Registry Annual Report 2020: a summary.

Background: The European Renal Association (ERA) Registry collects data on kidney replacement therapy (KRT) in patients with ESKD. This paper is a summary of the ERA Registry Annual Report 2020, also including comparisons among primary renal disease (PRD) groups. Methods: Data were collected from 52 national and regional registries from 34 European countries and countries bordering the Mediterranean Sea: 35 registries from 18 countries providing individual level data and 17 registries from 17 countries providing aggregated data. Using this data, KRT incidence and prevalence, kidney transplantation rates, expected remaining lifetimes and survival probabilities were calculated. Results: A general population of 654.9 million people was covered by the ERA Registry in 2020. The overall incidence of KRT was 128 per million population (p.m.p.). In incident KRT patients, 54% were older than 65 years, 63% were men and the most common PRD was diabetes mellitus (21%). Regarding initial treatment modality in incident patients, 85% received haemodialysis (HD), 11% received peritoneal dialysis (PD) and 4% received a pre-emptive kidney transplant. On 31 December 2020, the prevalence of KRT was 931 p.m.p. In prevalent patients, 45% were older than 65 years, 60% were men and glomerulonephritis was the most common PRD (18%). Of these patients, 58% were on HD, 5% on PD and 37% were living with a kidney transplant. The overall kidney transplantation rate in 2020 was 28 p.m.p., with a majority of kidney grafts from deceased donors (71%). The unadjusted 5-year survival, based on incident dialysis patient from 2011-15, was 41.8%. For patients having received a deceased donor transplant, the unadjusted 5-year survival probability was 86.2% and for patients having received a living donor transplant it was 94.4%. When comparing data by PRD group, differences were found regarding the distribution of age groups, sex and treatment modality received.

Incidence of End Stage Kidney Disease and context of dialysis initiation / Incidence de la maladie rénale chronique stade 5 traitée par suppléance et contexte d'initiation de la dialyse

On the occasion of the 20th anniversary of the REIN (French Renal Epidemiology and Information Network), a summary work on the contributions of the national French ESKD register was carried out. On the issue of ESKD incidence, the following key messages were retained. Thanks to several studies conducted using data from the REIN registry, the spatial variations of incidence of stage 5 chronic kidney disease in the replacement stage could be explained, in part, by the health condition of the general population as well as by the socio-economic context and differences in practices. Just like what is observed in other countries, the incidence is stabilising, or even decreasing, especially among people who do not have diabetes. Thanks to the registry having provided an indicator on the initiation of the dialysis, a decrease in the rate of initiation of emergency dialysis (i.e., initiated less than 24 hours after a nephrology evaluation considering a vital risk for the patient) has been observed, resulting from an effort to understand and better anticipate the starting of the replacement.

À l'occasion des 20 ans du REIN (Réseau Epidémiologie et Information en Néphrologie), un travail de synthèse sur les apports du registre a été mené. Sur la question de l'incidence de la maladie rénale chronique stade 5, les messages clés suivants ont été retenus. Grâce à plusieurs études menées à partir des données du registre REIN, les variations spatiales d'incidence de la maladie rénale chronique stade 5 au stade de la suppléance ont pu être expliquées, en partie, par l'état de santé de la population générale mais aussi par le contexte socioéconomique et des différences de pratiques. À l'image de ce qui est observé dans d'autres pays, l'incidence est en voie de stabilisation, voire à la baisse, en particulier chez les personnes non diabétiques. Grâce à la mise à disposition par le registre d'un indicateur sur l'initiation de la dialyse, on observe une diminution du taux d'initiation de la dialyse en urgence (c'est-à-dire initiée moins de 24 heures après une évaluation néphrologique considérant un risque vital pour le patient) résultant d'un effort pour comprendre et mieux anticiper le démarrage de la suppléance. L'initiation de la dialyse sur cathéter, autre indicateur de la prise en charge, n'a pour l'instant pas diminué mais avec la mise en place du forfait MRC en octobre 2019 et à distance de la pandémie, la préparation à l'épuration extrarénale devrait être mieux anticipée.

Prevalence of End Stage Kidney Disease and distribution of treatment modalities / Prévalence de l'IRCT et part des différentes modalités de traitement

On the occasion of the 20th anniversary of the REIN (French Renal Epidemiology and Information Network), a summary work on the contributions of the national French ESKD register was carried out. On the issue of ESKD prevalence, the following key messages were retained. While chronic kidney disease affects all age groups, there always are more patients to treat in the older age groups, with a median age of 71.1 years (IIQ 60.3-80.0) under dialysis and 58.7 years (IIQ 47.4-68.3) under renal transplant. Despite an increase in transplant activity and improved survival of grafts, the gap between the number of dialysis patients and transplant patients at the end of each year is only moderately reduced. There has been a moderate decrease in the proportion of in-centre haemodialysis that is explained by a significant increase in medicalised dialysis units (out-centre haemodialysis) and a decrease in self-care haemodialysis. Finally, a stable home-based care has been observed despite the ministerial incentives and the recommendations of the French-speaking scientific society (SFNDT-white paper).

À l'occasion des 20 ans du REIN (Réseau Epidémiologie et Information en Néphrologie), un travail de synthèse sur les apports du registre a été mené. Sur la question de la prévalence de la maladie rénale stade 5, les messages clés suivants ont été retenus. Si la maladie rénale chronique touche toutes les tranches d'âge, il y a toujours plus de patients à prendre en charge dans les tranches d'âge les plus élevées, avec un âge médian de 71,1 ans (Intervalle Inter Quartile (IIQ) 60,3-80,0) en dialyse et 58,7 ans (IIQ 47,4-68,3) en transplantation rénale. Malgré une augmentation de l'activité de greffe et une meilleure survie des greffons, l'écart entre le nombre de patients dialysés et greffés à la fin de chaque année ne diminue que de façon modérée. On observe une baisse modérée de la part de l'hémodialyse en centre expliquée par une hausse importante des unités de dialyse médicalisée (UDM) et une baisse de l'autodialyse. Enfin, on note une prise en charge à domicile stable malgré les incitations ministérielles et les recommandations de la société savante (SFNDT-livre blanc).

REIN: a tool for the benefit of renal transplantation / REIN : un outil au service de l'accès à la greffe

On the occasion of the 20th anniversary of the REIN (French Renal Epidemiology and Information Network), a summary work on the contributions of the national French ESKD register was carried out. On the issue of access to renal transplantation for ESKD patients, the following key messages were retained. The registry of the REIN includes data about kidney transplant and dialysis. It thus allows evaluating the access to kidney transplant in France based on the needs of the population with stage 5 CKD treated by renal replacement therapy. The data produced by the registry is complementary to the data in the report of the Agence de la biomédecine (Agency of Biomedicine) based on the activity of the transplant centres and the population of registered patients waiting for a transplant. The proportion of preemptive transplant (transplant without prior recourse to dialysis) as well as that of preemptive registration (before starting dialysis) have increased since 2012 but remain low. The proportion of preemptive transplant as the first replacement therapy remains low and stable over time at around 3 to 4%. The access to the waiting list and the transplant varies depending on the age and co-morbidities of the patients (diabetes, obesity) as well as on the region. The rates of registration on the kidney transplant waiting list at the time of initiation of dialysis and at 1 year from the start have been increasing since 2012, irrespective of the patients' characteristics, though it remains low in elderly, diabetic and severely obese patients. This is partly the result related to the publication of the HAS (French National Authority for Health) recommendations in 2015 and the publications on the disparities in access to transplants established thanks to the REIN registry. The causes of non-registration at the time of initiation of dialysis have changed over time with some patients not registering for contraindication steadily decreasing since 2012. Thanks to several studies conducted using data from the registry, the variations in access to the list could be explained, partly, by the health condition of the dialysis population as well as by the socio-economic context and differences in practices according to dialysis networks. The median waiting time for a kidney transplant has been gradually increasing since 2012, with a delta of about 8 months between 2012 and 2020. However, the waiting time between the initiation of dialysis and the transplant has increased less significantly. The probability of receiving a first kidney transplant depends on the age, diabetic status and obesity of the patient, and has remained stable over time.

À l'occasion des 20 ans du REIN (Réseau Épidémiologie et Information en Néphrologie), un travail de synthèse sur les apports du registre a été mené. Sur la question de l'accès à la greffe rénale des patients avec une maladie rénale stade 5, les messages clés suivants ont été retenus. Le registre du REIN intègre les données de la greffe rénale et de la dialyse. Il permet ainsi d'évaluer l'accès à la greffe rénale en France à partir des besoins de la population MRC au stade 5 traitée par suppléance. Les données produites par le registre sont complémentaires des données du rapport de l'Agence de la biomédecine basées sur l'activité des centres de greffe et la population des patients inscrits en attente de greffe. La part de la greffe préemptive (greffe sans recours préalable à la dialyse) ainsi que celle de l'inscription préemptive (avant le démarrage de la dialyse) ont augmenté depuis 2012 mais restent faibles. La proportion de greffe préemptive comme premier traitement de suppléance reste faible et stable dans le temps aux alentours de 3 à 4 %. L'accès à la liste d'attente et à la greffe varie selon l'âge et les comorbidités des patients (diabète, obésité) mais aussi selon la région. Les taux d'inscription sur liste d'attente de greffe rénale au moment de l'initiation de la dialyse et à 1 an du début augmentent depuis 2012, quelles que soient les caractéristiques des patients même si elle reste faible chez les patients âgés, diabétiques et présentant une obésité sévère. Ceci est en partie le résultat lié à la publication des recommandations HAS en 2015 et aux publications sur les disparités d'accès à la greffe établies grâce au registre REIN. Les causes de non-inscription au moment de l'initiation de la dialyse ont évolué dans le temps avec une proportion de patients non inscrits pour contre-indication en baisse constante depuis 2012. Grâce à plusieurs études menées à partir des données du registre, les variations d'accès à la liste ont pu être expliquées, en partie, par l'état de santé de la population dialysée mais aussi par le contexte socioéconomique et des différences de pratiques selon les filières de prise en charge. Le temps d'attente médian avant une greffe rénale augmente progressivement depuis 2012 avec un delta d'environ 8 mois entre 2012 et 2020 ; cependant, le temps d'attente entre l'initiation de la dialyse et la greffe a augmenté de façon moins importante. La probabilité de recevoir une première greffe rénale dépend de l'âge, du statut diabétique et de l'obésité du patient et est restée stable au cours du temps.

REIN: a tool to evaluate pratices / REIN : un outil au service de l'évaluation des pratiques

On the occasion of the 20th anniversary of the REIN (French Renal Epidemiology and Information Network), a summary work on the contributions of the national French ESKD register was carried out. On the issue of its role in practices evaluation, the following key messages were retained. The evaluation of our practices allows improving them as proposed by the concept of the Edward Deming wheel (Plan, Do, Check, Act). Measurement also allows setting goals and targets. Where there are recommendations available, the REIN indicators allow comparison with the identified targets. The REIN registry is an interesting tool to observe the deployment and impact of the recommendations in dialysis units and to evaluate the professional practices taking into account the patients' characteristics and the changes in the recommendations. Finally, the treatment indicators analysed using REIN data show the great diversity of practices from one region to another, the result of habits, training of nephrologists, the history of the care offered and sometimes the geography of the region and its population.

À l'occasion des 20 ans du REIN (Réseau Épidémiologie et Information en Néphrologie), un travail de synthèse sur les apports du registre a été mené. Sur la question de REIN comme outil pour l'évaluation des pratiques, les messages clés suivants ont été retenus. L'évaluation de nos pratiques permet de les améliorer comme proposé par le concept de la roue d'Edward Deming (Plan, Do, Check, Act). Se mesurer permet également de fixer des objectifs et des cibles. Lorsque des recommandations sont disponibles, les indicateurs REIN permettent de se comparer aux cibles identifiées. Le registre REIN est un outil intéressant pour observer le déploiement et l'impact des recommandations dans les unités de dialyse et évaluer les pratiques professionnelles en tenant compte des caractéristiques des patients et de l'évolution des recommandations. Enfin, les indicateurs de prise en charge analysés à l'aide des données REIN montrent la grande diversité des pratiques d'une région à l'autre, fruit des habitudes, de la formation des néphrologues, de l'historique de l'offre de soins et parfois de la géographie de la région et de sa population.

REIN: a tool to highlight inequalities in health / REIN : un outil au service de l'éclairage des inégalités en santé

On the occasion of the 20th anniversary of the REIN (French Renal Epidemiology and Information Network), a summary work on the contributions of the national French ESKD register was carried out. On the issue of Social Inequalities in Health, the following key messages were retained. Social inequalities in health exist throughout the journey of a patient with chronic kidney disease and manifest as territorial inequalities in access to home-based or independent dialysis treatment and to transplant, whether preemptive or otherwise. SIH are observed in adults as well as in the paediatric population. The female gender appears to be associated with a disparity in access to kidney transplant.

À l'occasion des 20 ans du REIN (Réseau Epidémiologie et Information en Néphrologie), un travail de synthèse sur les apports du registre a été mené. Sur la question des inégalités sociales de santé, les messages clés suivants ont été retenus. Les inégalités sociales de santé existent tout au long du parcours du patient atteint d'une maladie rénale chronique et se traduisent par des inégalités territoriales d'accès au traitement par dialyse au domicile ou autonome, à la greffe qu'elle soit préemptive ou non. Les ISS sont retrouvées chez l'adulte mais aussi dans la population pédiatrique. Le genre féminin semble associé à une disparité d'accès à la greffe rénale.

REIN: a tool at the service of the paediatric patients / REIN : un outil au service des patients pédiatriques

On the occasion of the 20th anniversary of the REIN (French Renal Epidemiology and Information Network), a summary work on the contributions of the national French ESKD register was carried out. On the issue of paediatric CKD patients, the following key messages were retained. Paediatric stage 5 chronic kidney disease (CKD) has particularities that require to be analysed and taken into account because the mortality of these patients remains 30 times higher than that of children of the same age. The REIN registry enables illustrating the specificities of stage 5 CKD in the paediatric age-group in France and providing a set of indicators making it possible to describe the future of these patients as well as the choices made concerning the modalities of replacement therapy. As compared to other European countries, the incidence and prevalence of stage 5 CKD in France is in the middle range for children under 15 and 20 years old. Renal transplant is by far the leading treatment for stage 5 CKD in children and adolescents under 18 years of age in France, allowing to offer these patients the best possible life expectancy. Owing to the small volume of patients, only a nationwide registry can provide an unbiased view and enables analysing this population requiring a hyperspecialised treatment. The participation of French paediatric nephrologists in the REIN French registry also enables providing input to the European registry (ESPN/ERA www.espn-reg.org/index.jsp) and the international registry (IPNA https://ipna-registry.org) (Consulted on September 15th 2022) and thus the possibility of international studies, which are vital to be in line with an approach to improving practices.

À l'occasion des 20 ans du REIN (Réseau Epidémiologie et Information en Néphrologie), un travail de synthèse sur les apports du registre a été mené. Sur la question des patients pédiatriques, les messages clés suivants ont été retenus. La maladie rénale chronique (MRC) stade 5 pédiatrique a des particularités qui nécessitent d'être analysées et prises en compte car la mortalité de ces patients reste 30 fois supérieure à celle des enfants du même âge. Le registre REIN permet d'illustrer les spécificités de la MRC stade 5 à l'âge pédiatrique en France et de fournir un ensemble d'indicateurs permettant de décrire le devenir de ces patients ainsi que les choix faits concernant les modalités de traitement de suppléance. En comparaison à d'autres pays européens, l'incidence et la prévalence de la MRC stade 5 en France se situent dans les valeurs moyennes chez les enfants de moins de 15 et 20 ans. La transplantation rénale est de loin le premier traitement de la MRC stade 5 parmi les enfants et les adolescents de moins de 18 ans en France, permettant d'offrir à ces patients la meilleure espérance de vie possible. En raison du petit volume de patients, seul un registre à l'échelon national permet d'avoir une vision non biaisée et d'analyser cette population nécessitant une prise en charge hyperspécialisée. La participation des néphropédiatres français au registre français REIN permet aussi d'alimenter le registre européen (ESPN/ ERA www.espn-reg.org/index.jsp) et le registre international (IPNA https://ipna-registry.org) (Consulté le 15 septembre 2022) et ainsi la possibilité d'études internationales, indispensables pour s'inscrire dans une démarche d'amélioration des pratiques.

The information system of REIN / Le système d'information de REIN

On the occasion of the 20th anniversary of the REIN (French Renal Epidemiology and Information Network), a summary work on the contributions of the national French ESKD register was carried out. On the issue of its information system, the following key messages were retained. The REIN information system accompanies the register throughout the life cycle of the data. Two collection tools, one for dialysis, the other for transplantation are accessible via a secure WEB site. Several data quality control tools have been added. Finally, several reporting tools, including a geographic information system completes REIN's information system.

À l'occasion des 20 ans du REIN (Réseau Épidémiologie et Information en Néphrologie), un travail de synthèse sur les apports du registre a été mené. Sur la question de son système d'information, les messages clés suivants ont été retenus. Le système d'information de REIN accompagne le registre sur tout le cycle de vie de la donnée. Deux outils de recueil, l'un pour la dialyse, l'autre pour la greffe sont accessible via un site WEB sécurisé. Plusieurs outils de contrôle de la qualité des données y ont été ajoutés. Et enfin, plusieurs outils de retours d'information, dont un système d'information géographique, complètent le système d'information de REIN.

Interactive tool for visualizing disparities in access to the waiting list and home dialysis / Outil interactif de visualisation des disparités dans l'accès à la liste d'attente et à la dialyse à domicile

Healthcare professionals and patient associations want to identify any disparities within the different regions, particularly in access to the waiting list for a kidney transplant and to home dialysis. An application containing the results of two REIN studies on these two issues was created to meet this need. It is now available for consultation on the professional portal of the Biomedicine Agency.

Un des besoins des professionnels de santé et des associations de patients est d'identifier au sein des différentes régions les éventuelles disparités, notamment dans l'accès à la liste d'attente pour une greffe rénale et à la dialyse à domicile. Une application reprenant les résultats de deux études du Réseau épidémiologique et information en néphrologie (REIN) portant sur ces deux problématiques a été créée pour répondre à ce besoin. Elle est désormais disponible à la consultation sur le portail des professionnels de l'Agence de la biomédecine.

Diversity of the quality of data collection in a registry: proposal of an analysis approach and application to the REIN register / Diversité de la qualité de recueil des données dans un registre : proposition d'une démarche d'analyse et application au registre REIN

Missing data may lead to bias and loss of information in epidemiological research. In this article, we propose an approach to analyze missing data on comorbidity variables in a register with consideration of the territorialized organization of the collection. To illustrate this approach, we used the national REIN registry as an application case.

Les données manquantes peuvent introduire des biais et des pertes d'informations dans les études épidémiologiques. Dans cet article, nous proposons une démarche d'analyse des données manquantes sur des variables de comorbidités dans un registre, avec prise en compte de l'organisation territorialisée du recueil. Afin d'illustrer cette démarche, nous avons utilisé le registre national du Réseau épidémiologie et information en néphrologie (REIN) comme cas d'application.

Social deprivation reduced registration for kidney transplantation through markers of nephrological care: a mediation analysis.

OBJECTIVES: We assessed the direct and indirect effect of social deprivation mediated by modifiable markers of nephrological follow-up on registration on the renal transplantation waiting-list. STUDY DESIGN AND SETTINGS: From the Renal Epidemiology and Information Network, we included French incident dialysis patients eligible for a registration evaluation between January 2017 and June 2018. Mediation analyses were conducted to assess effects of social deprivation estimated by quintile 5 (Q5) of the European Deprivation Index on registration defined as wait-listing at dialysis start or within the first 6 months. RESULTS: Among the 11,655 included patients, 2,410 were registered. The Q5 had a direct effect on registration (odds ratio [OR]: 0.82 [0.80-0.84]) and an indirect effect mediated by emergency start dialysis (OR: 0.97 [0.97-0.98]), hemoglobin <11 g/dL and/or lack of erythropoietin (OR 0.96 [0.96-0.96]) and albumin <30 g/L (OR: 0.98 [0.98-0.99]). CONCLUSION: Social deprivation was directly associated with a lower registration on the renal transplantation waiting-list but its effect was also mediated by markers of nephrological care, suggesting that improving the follow-up of the most deprived patients should help to reduce disparities in access to transplantation.

Increasing numbers and improved overall survival of patients on kidney replacement therapy over the last decade in Europe: an ERA Registry study.

BACKGROUND: The aim of this study was to describe the trends in the incidence, prevalence and survival of patients on kidney replacement therapy (KRT) for end-stage kidney disease (ESKD) across Europe from 2008 to 2017. METHODS: Data from renal registries in 9 countries and 16 regions that provided individual patient data to the ERA Registry from 2008 to 2017 were included. These registries cover 34% of the general population in Europe. Crude and standardized incidence and prevalence per million population (pmp) were determined. Trends over time were studied using Joinpoint regression. Survival probabilities were estimated using Kaplan-Meier analysis and hazard ratios (HRs) using Cox regression analysis. RESULTS: The standardized incidence of KRT was stable [annual percentage change (APC): -1.48 (-3.15; 0.21)] from 2008 (146.0 pmp) to 2011 (141.6 pmp), followed by a slight increase [APC: 1.01 (0.43; 1.60)] to 148.0 pmp in 2017, although trends in incidence varied across countries. This increase was primarily due to a rise in the incidence of KRT in men older than 65 years. Moreover, as a cause of kidney failure, diabetes mellitus is increasing. The standardized prevalence increased from 2008 (990.0 pmp) to 2017 (1166.8 pmp) [APC: 1.82 (1.75; 1.89)]. Patient survival on KRT improved in the time period 2011-13 compared with 2008-[adjusted HR: 0.94 (0.93; 0.95)]. CONCLUSION: This study showed an overall increase in the incidence and prevalence of KRT for ESKD as well as an increase in the KRT patient survival over the last decade in Europe.

Is there sex disparity in vascular access at dialysis initiation in France? A mediation analysis using data from the Renal Epidemiology and Information Network registry.

Background: This study was conducted to estimate the direct effect of sex on the proportion of hemodialysis (HD) catheters used at dialysis initiation and to investigate whether predialysis care or socioeconomic status acted as a mediator of the sex effect. Methods: Patients who started dialysis between January 1, 2017, and June 30, 2018, in France were included using the data of the Renal Epidemiology and Information Network (REIN) registry. We performed logistic regression to study the association between sex and the proportion of HD catheters used. A mediation analysis with a counterfactual approach was carried out to evaluate whether there was an indirect effect of sex through the proxies of predialysis care {hemoglobin, albumin levels, glomerular filtration rate [GFR] at dialysis initiation} and socioeconomic status. Because an interaction between sex and social deprivation has been identified, we performed a subgroup analysis on deprived and nondeprived patients. Results: The study included 16 032 patients, and the sex ratio (male to female) was 10 405:5627. In the multivariable analysis, women were associated with a greater risk of starting dialysis with a catheter {odds ratio [OR], 1.32 [95% confidence interval (CI): 1.23-1.42]}. There was an indirect effect of sex on the proportion of HD catheters through proxies for predialysis care {albuminemia <30 g/L [OR, 1.08 (95% CI: 1.05-1.10)], hemoglobin <11 g/dL [OR, 1.03 (95% CI: 1.02-1.04)], glomerular filtration rate <7 mL/min [OR, 1.05 (95% CI: 1.04-1.07)]}. Among deprived patients, there was no direct effect of sex on catheter proportion. Conclusions: Women were associated with a higher risk of starting dialysis through an HD catheter. The effect of sex was mediated by predialysis care, particularly for deprived patients.

[Descriptions of hospitalizations during the year 2019 among dialysis patients in France]. / Descriptions des hospitalisations au cours de l'année 2019 des patients dialysés en France.

INTRODUCTION: The possibility of indirect linkage between data from the French REIN registry and data from the National Health Data System makes it possible to enhance knowledge of the care pathway of patients with severe kidney disease. Taking an interest in hospitalizations makes it possible to understand the burden of this disease, both for patients, in terms of comorbidities, complications and quality of life but also for society in terms of care load, need for organization of the care offer and costs. METHODS: Patients on dialysis in 2019 were identified from REIN. The information on hospital stays comes from an extraction of the National Health Data System linked with REIN. The hospitalization rate corresponds to the number of hospital stays over the period, relative to the number of people at risk on dialysis over the period. RESULTS: After excluding dialysis sessions, 36,962 patients had a hospital stay in 2019: 36,738 in medicine, surgery, obstetrics, 2863 in rehabilitation, 531 in home hospitalizations and 201 in psychiatry facilities. This represents a total of 146,743 stays, including 140,372 in medicine, surgery, obstetrics. The hospitalization rate in medicine, surgery, obstetrics is 259 stays for 100 person-years. The reasons vary according to age, type of hospitalization (with or without overnight stays) and mode of discharge (home, death or transfer). The median amounts for a stay vary from €7920 in rehabilitation to €719 in medicine, surgery, obstetrics without overnight stay. Due to the volumes, stays for cardiovascular pathology represent a high total amount over the year. Hospitalizations for infection have significant median costs. DISCUSSION AND CONCLUSION: The results presented in this article confirm the important place of hospitalization in the trajectory of dialysis patients. Hospitalizations in medicine, surgery, obstetrics represent 96% of hospitalizations. For the first time, this study shows the very low place of hospitalizations in psychiatry and rehabilitation facilities.

An algorithm for identifying chronic kidney disease in the French national health insurance claims database.

BACKGROUND: Published algorithms for identifying chronic kidney disease in healthcare claims databases have poor performance except in patients with renal replacement therapy. We propose and describe an algorithm to identify all stage chronic kidney disease in a French healthcare claims databases and assessed its performance by using data from the Renal Epidemiology and Information Network registry and the French Childhood Cancer Survivor Study cohort. METHODS: A group of experts met several times to define a list of items and combinations of items that could be related to chronic kidney disease. For the French Childhood Cancer Survivor Study cohort, information on confirmed chronic kidney disease cases extracted from medical records was considered the gold standard (KDIGO definition). Sensitivity, specificity, and positive and negative predictive value and kappa coefficients were estimated. The contribution of each component of the algorithm was assessed for 1 and 2 years before the start of renal replacement therapy for confirmed end-stage kidney disease in the Renal Epidemiology and Information Network registry. RESULTS: The algorithm's sensitivity was 78%, specificity 97.4%, negative predictive value 98.4% and positive predictive value 68.7% in French Childhood Cancer Survivor Study cohort and the kappa coefficient was 0.79 for agreement with the gold standard. The algorithm 93.6% and 55.1% of confirmed incident end-stage kidney disease cases from the Renal Epidemiology and Information Network registry when considering 1 year and 2 years, respectively, before renal replacement therapy start. CONCLUSIONS: The algorithm showed good performance among younger patients and those with end-stage kidney disease in the twol last years prior to renal replacement therapy. Future research will address the ability of the algorithm to detect early chronic kidney disease stages and to classify the severity of chronic kidney disease.

Which data in the French registry for advanced chronic kidney disease for public health and patient care?

Chronic kidney disease is a chronic non-transmittable disease of increasing incidence. The advanced stages are complicated by high morbidity and mortality, and individual management is complex due to the various treatments required at stage 5 including renal replacement. For the healthcare system, this disease also requires complex care organization. National registers of patients on renal replacement therapy have been developed to improve patient management and care arrangements. The purpose of our review was to report on the history of the French registry, its organization, the information collected and its evolution in response to the stage 5 problem. We successively detail the information system with its inclusion criteria, architecture and tools developed, its security rules, mode and type of information collected, its quality controls and, finally, the glossary of data available within the registry.

Switch from Hemodialysis to Peritoneal Dialysis: Does the Time Spent on Hemodialysis Impact Outcomes in Peritoneal Dialysis?

INTRODUCTION: Switch from hemodialysis (HD) to peritoneal dialysis (PD) is unfrequent, but incentive strategies to perform PD can lead to an increase of these transitions. However, data on transitioning from HD to PD are scarce. We hypothesized that time spent on HD before transfer to PD would impact PD outcomes. METHODS: This registry-based, nationwide study analyzed patients transferred from HD to PD. Patients who began HD between January 2008 and December 2016 were included. Cox and Fine and Gray regression models were used to explore the relationship between time spent on HD before PD and outcomes in PD: PD cessation for death or retransfer to HD (composite endpoint); for death; and for retransfer to HD. RESULTS: Over the study period, 1,985 of the 77,587 HD starters (3%) were transferred to PD. The median time spent on HD before transfer to PD was 1.94 months (interquartile range [IQR] 1.02-4.01). The median survival time on PD after this transition was 20 months (IQR 18-21). Time spent on HD before PD was associated with increased risk of death or retransfer to HD (cause-specific hazard ratio [cs-HR] 1.01, 95% confidence interval [CI]: 1-1.02 for a 1-month increase) and death (cs-HR 1.02, 95% CI: 1.01-1.03) but not with retransfer to HD censored on death (cs-HR 1.00, 95% CI: 0.99-1.01). The results were similar when considering competing events. DISCUSSION/CONCLUSION: Switch from HD to PD is rare in France. Time spent on HD before transfer is associated with patient survival but not with retransfer to HD.