title: Residual Kidney Function Decline and Mortality in Incident Hemodialysis Patients.
abstract: In patients with ESRD, residual kidney function (RKF) contributes to achievement of adequate solute clearance. However, few studies have examined RKF in patients on hemodialysis. In a longitudinal cohort of 6538 patients who started maintenance hemodialysis over a 4-year period (January 2007 through December 2010) and had available renal urea clearance (CLurea) data at baseline and 1 year after hemodialysis initiation, we examined the association of annual change in renal CLurearate with subsequent survival. The median (interquartile range) baseline value and mean±SD annual change of CLureawere 3.3 (1.9-5.0) and -1.1±2.8 ml/min per 1.73 m2, respectively. Greater CLurearate 1 year after hemodialysis initiation associated with better survival. Furthermore, we found a gradient association between loss of RKF and all-cause mortality: changes in CLurearate of -6.0 and +3.0 ml/min per 1.73 m2per year associated with case mix-adjusted hazard ratios (95% confidence intervals) of 2.00 (1.55 to 2.59) and 0. 61 (0.50 to 0.74), respectively (reference: -1.5 ml/min per 1.73 m2per year). These associations remained robust against adjustment for laboratory variables and ultrafiltration rate and were consistent across strata of baseline CLurea, age, sex, race, diabetes status, presence of congestive heart failure, and hemoglobin, serum albumin, and serum phosphorus levels. Sensitivity analyses using urine volume as another index of RKF yielded consistent associations. In conclusion, RKF decline during the first year of dialysis has a graded association with all-cause mortality among incident hemodialysis patients. The clinical benefits of RKF preservation strategies on mortality should be determined.
authors.affiliation: Harold Simmons Center for Kidney Disease Research and Epidemiology, Division of Nephrology and Hypertension, University of California, Irvine School of Medicine, Orange, California.
authors.forename: Yoshitsugu
authors.initials: Y
authors.lastname: Obi
authors.affiliation: Harold Simmons Center for Kidney Disease Research and Epidemiology, Division of Nephrology and Hypertension, University of California, Irvine School of Medicine, Orange, California.
authors.forename: Connie M
authors.initials: CM
authors.lastname: Rhee
authors.affiliation: Division of Nephrology, Northwell Health System, Great Neck, New York.
authors.forename: Anna T
authors.initials: AT
authors.lastname: Mathew
authors.affiliation: Harold Simmons Center for Kidney Disease Research and Epidemiology, Division of Nephrology and Hypertension, University of California, Irvine School of Medicine, Orange, California.
authors.forename: Gaurang
authors.initials: G
authors.lastname: Shah
authors.affiliation: Harold Simmons Center for Kidney Disease Research and Epidemiology, Division of Nephrology and Hypertension, University of California, Irvine School of Medicine, Orange, California.
authors.forename: Elani
authors.initials: E
authors.lastname: Streja
authors.affiliation: DaVita Clinical Research, Minneapolis, Minnesota.
authors.forename: Steven M
authors.initials: SM
authors.lastname: Brunelli
authors.affiliation: Division of Nephrology, University of Tennessee Health Science Center, Memphis, Tennessee.|Nephrology Section, Memphis Veterans Affairs Medical Center, Memphis, Tennessee.
authors.forename: Csaba P
authors.initials: CP
authors.lastname: Kovesdy
authors.affiliation: Kidney Research Institute and Harborview Medical Center, Division of Nephrology, University of Washington, Seattle, Washington.
authors.forename: Rajnish
authors.initials: R
authors.lastname: Mehrotra
authors.affiliation: Harold Simmons Center for Kidney Disease Research and Epidemiology, Division of Nephrology and Hypertension, University of California, Irvine School of Medicine, Orange, California; kkz@uci.edu.|Fielding School of Public Health, University of California, Los Angeles, Los Angeles, California; and.|Los Angeles Biomedical Research Institute, Harbor-University of California, Los Angeles, Torrance, California.
authors.forename: Kamyar
authors.initials: K
authors.lastname: Kalantar-Zadeh
mesh_terms: D005260:Female; D006801:Humans; D007668:Kidney / Q000503:physiopathology*; D007676:Kidney Failure, Chronic / Q000401:mortality* / Q000503:physiopathology / Q000628:therapy*; D007677:Kidney Function Tests; D008297:Male; D008875:Middle Aged; D006435:Renal Dialysis / Q000401:mortality*; D012189:Retrospective Studies
keywords: chronic hemodialysis; end stage kidney disease; end-stage renal disease; hemodialysis; hemodialysis adequacy; renal function decline