title: Variability of the Estimated Glomerular Filtration Rate in the First Year after Kidney Transplantation Is an Independent Risk Factor for Poor Renal Allograft Outcomes: A Retrospective Cohort Study.
abstract: Renal function in the first year after kidney transplantation (KT) can predict long-term renal graft survival. This study investigated whether estimated glomerular filtration rate (eGFR) variability during the first year after KT is a risk factor for poor renal allograft outcomes. This retrospective cohort study included 3077 patients who underwent repeated eGFR measurements for 1 year after KT at Severance Hospital Transplantation Center between 1979 and 2012. The eGFR variability during the first year after KT was the predictor. The patients were divided into four quartile groups of eGFR variability according to the coefficient of variation for eGFR (eGFR-CV). We selected a cutoff of eGFR-CV for graft failure and performed the sensitivity analyses. The graft outcome was worse in the highest quartile group of eGFR variability than in the other groups among all patients (Q4: HR 1.631, 95% CI 1.278-2.081; p < 0.0001) and among patients without AR (Q4: HR 1.425, 95% CI 1.024-1.982; p = 0.0358) after adjusting for eGFR at 1 year after KT and other covariates. Additionally, all-cause mortality was higher in this highest quartile group than in the other groups among all patients but not among patients without AR. Higher eGFR-CVs than the cutoff were significantly associated with a high risk of graft failure among all patients (HR 1.670, 95% CI 1.395-2.000; p < 0.0001) and among patients without AR (HR 1.899, 95% CI 1.457-2.477; p < 0.0001) after fully adjusting for covariates. For all-cause mortality, a higher eGFR-CV was an independent risk factor among all patients but not among patients without AR after adjusting for covariates. eGFR variability in the first year after KT is an independent risk factor for poor renal allograft outcomes.
authors.affiliation: Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Hoon Young
authors.initials: HY
authors.lastname: Choi
authors.affiliation: Department of Transplantation Surgery, Severance Hospital, Yonsei University Health System, Seoul, Korea.|The Research Institute for Transplantation, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Kyu Ha
authors.initials: KH
authors.lastname: Huh
authors.affiliation: Department of Transplantation Surgery, Severance Hospital, Yonsei University Health System, Seoul, Korea.|The Research Institute for Transplantation, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Jae Geun
authors.initials: JG
authors.lastname: Lee
authors.affiliation: Department of Biostatistics Collaboration Unit, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Mi Kyung
authors.initials: MK
authors.lastname: Song
authors.affiliation: Department of Transplantation Surgery, Severance Hospital, Yonsei University Health System, Seoul, Korea.|The Research Institute for Transplantation, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Myoung Soo
authors.initials: MS
authors.lastname: Kim
authors.affiliation: Department of Transplantation Surgery, Severance Hospital, Yonsei University Health System, Seoul, Korea.|The Research Institute for Transplantation, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Yu Seun
authors.initials: YS
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Korea.|The Research Institute for Transplantation, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Beom Seok
authors.initials: BS
authors.lastname: Kim
mesh_terms: D000328:Adult; D000465:Algorithms; D005260:Female; D005919:Glomerular Filtration Rate; D006085:Graft Survival; D006801:Humans; D053208:Kaplan-Meier Estimate; D007668:Kidney / Q000503:physiopathology; D007676:Kidney Failure, Chronic / Q000601:surgery* / Q000628:therapy; D016030:Kidney Transplantation; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D012044:Regression Analysis; D012189:Retrospective Studies; D012307:Risk Factors; D016896:Treatment Outcome