Scientific Publications Database
Article Title: Hospitalizations in Dialysis Patients in Canada: A National Cohort Study.Authors: Molnar, Amber O; Moist, Louise; Klarenbach, Scott; Lafrance, Jean-Philippe; Kim, S Joseph; Tennankore, Karthik; Perl, Jeffrey; Kappel, Joanne; Terner, Michael; Gill, Jagbir; Sood, Manish M
Journal: Canadian journal of kidney health and disease Volume 5
Date of Publication:2018
Abstract:
BACKGROUND: Hospitalizations of chronic dialysis patients have not been previously studied at a national level in Canada. Understanding the scope and variables associated with hospitalizations will inform measures for improvement.OBJECTIVE: To describe the risk of all-cause and infection-related hospitalizations in patients on dialysis.DESIGN: Retrospective cohort study using health care administrative databases.SETTING: Provinces and territories across Canada (excluding Manitoba and Quebec).PATIENTS: Incident chronic dialysis patients with a dialysis start date between January 1, 2005, and March 31, 2014. Patients with a prior history of kidney transplantation were excluded.MEASUREMENTS: Patient characteristics were recorded at baseline. Dialysis modality was treated as a time-varying covariate. The primary outcomes of interest were all-cause and dialysis-specific infection-related hospitalizations.METHODS: Crude rates for all-cause hospitalization and infection-related hospitalization were determined per patient year (PPY) at 7 and 30 days, and at 3, 6, and 12 months postdialysis initiation. A stratified, gamma-distributed frailty model was used to assess repeat hospital admissions and to determine the inter-recurrence dependence of hospitalizations within individuals, as well as the hazard ratio (HR) attributed to each covariate of interest.RESULTS: A total of 38 369 incident chronic dialysis patients were included: 38 088 adults and 281 pediatric patients (age less than 18 years). There were 112 374 hospitalizations, of which 11.5% were infection-related hospitalizations. The all-cause hospitalization rate was similar for all adult age groups (age 65 years and older: 1.40, 1.35, and 1.18 admissions PPY at 7 days, 30 days, and 6 months, respectively). The all-cause hospitalization rate was higher for pediatric patients (1.67, 2.48, and 2.47 admissions PPY at 7 days, 30 days, and 6 months, respectively; adjusted HR: 2.73, 95% confidence interval [CI]: 2.37-3.15, referent age group: 45-64 years). Within the first 7 days after dialysis initiation, patients on peritoneal dialysis had a higher risk of all-cause hospitalization (HR: 1.27, 95% CI: 1.07-1.50) and infection-related hospitalization (HR: 2.05, 95% CI: 1.19-3.55) compared with patients on hemodialysis. Beyond 7 days, the risk did not differ significantly by dialysis modality. Female sex and Indigenous race were significant risk factors for all-cause hospitalization.LIMITATIONS: The cohort had too few home hemodialysis patients to examine this subgroup. The outcome of infection-related hospitalization was determined using diagnostic codes. Dialysis patients from Manitoba and Quebec were not included.CONCLUSIONS: In Canada, the rates of hospitalization were not influenced by dialysis modality beyond the initial 7-day period following dialysis initiation; however, the rate of hospitalization in pediatric patients was higher than in adults at every time frame examined.CONTEXTE: Le taux dhospitalisation des patients dialyses navait jamais fait lobjet dune etude pancanadienne. Une connaissance approfondie de la portee et des variables associees aux hospitalisations orientera les mesures damelioration.OBJECTIF DE LETUDE: Letude visait a mieux evaluer les risques dhospitalisations des patients dialyses; toutes causes confondues ou liees specifiquement a une infection.TYPE DETUDE: Il sagit dune etude de cohorte retrospective fondee sur des bases de donnees administratives en sante.CADRE DE LETUDE: Letude couvrait les provinces et territoires du Canada a lexception du Quebec et du Manitoba.PATIENTS: Letude a porte sur tous les patients dialyses a vie dont le traitement avait commence entre le 1er janvier 2005 et le 31 mars 2014. Les patients ayant recu une greffe renale ont ete exclus.MESURES: Les caracteristiques initiales des patients ont ete consignees, et la modalite de dialyse a ete traitee comme une co-variable sujette a changement dans le temps. La principale issue dinteret etait une hospitalisation due a une infection directement liee a la dialyse, ou une hospitalisation toutes causes confondues.METHODOLOGIE: Les taux bruts dhospitalisations toutes causes confondues (global) et dhospitalisations liees a une infection ont ete calcules en annees-patients (HAP) a differents moments suivant le debut de la dialyse (7 jours, 30 jours, 3 mois, 6 mois et 12 mois). Un modele stratifie de fragilite a distribution gamma a ete employe pour i) repertorier les hospitalisations repetees; ii) determiner linterrecurrence et le lien de dependance entre les hospitalisations pour chaque patient; et iii) etablir le rapport de risque (RR) attribue a chaque covariable dinteret.RESULTATS: En tout, 38 369 patients dialyses, soit 38 088 adultes et 281 patients mineurs (moins de 18 ans) ont ete inclus dans letude. Au cours de la periode etudiee, on a repertorie 112 374 hospitalisations, dont 11,5 % etaient dues a une infection en lien direct avec la dialyse. Le taux dhospitalisations global etait similaire pour tous les groupes dage chez les patients adultes. Par exemple, chez les patients ages de 65 ans et plus, ce taux se situait respectivement a 1,40 HAP, a 1,35 HAP et a 1,18 HAP lorsque calcule 7 jours, 30 jours et 6 mois apres linitiation de la dialyse. Lorsque compare au groupe des 45-64 ans, le taux dhospitalisations global sest avere plus eleve chez les patients pediatriques (1,67 HAP a 7 jours, 2,48 HAP a 30 jours et 2,47 HAP a 6 mois) post-initiation de la dialyse (RR: 2,73; IC 95 %: 2,37-3,15). Dans les 7 jours suivant linitiation du traitement, les patients traites par dialyse peritoneale presentaient un risque plus eleve dhospitalisation toutes causes confondues (RR: 1,27; IC 95 %: 1,07-1,50) ou dhospitalisation liee a une infection (RR: 2,05; IC 95 %: 1,19-3,55) que les patients hemodialyses. Par contre, cet ecart entre les modalites de dialyse netait plus observable au-dela des sept premiers jours. Enfin, le fait detre autochtone ou de sexe feminin saverait un facteur de risque dhospitalisation significatif (toutes causes confondues).LIMITES DE LETUDE: Plusieurs facteurs limitent la portee des resultats: i) la cohorte comptait trop peu de patients hemodialyses a domicile pour permettre une analyse de ce sous-groupe; ii) les hospitalisations relatives a une infection ont ete etablies a laide de codes diagnostiques; et iii) les patients dialyses residant au Quebec et au Manitoba etaient exclus de letude.CONCLUSION: Au Canada, au-dela des sept jours suivant linitiation de la dialyse, la modalite employee na plus dinfluence sur les taux dhospitalisations. Cependant, a tous les moments post-initiation mesures, les taux dhospitalisations se sont averes plus eleves chez les patients pediatriques que chez les adultes.