title: Overhydration measured by bioimpedance analysis and the survival of patients on maintenance hemodialysis: a single-center study.
abstract: BACKGROUND
  Bioimpedance analysis (BIA) helps measuring the constituents of the body noninvasively. Prior studies suggest that BIA-guided fluid assessment helps to predict survival in dialysis patients. We aimed to evaluate the clinical usefulness of BIA for predicting the survival rate of hemodialysis patients in Korea.
  
  
  METHODS
  We conducted a single-center retrospective study. All patients were diagnosed with end-stage renal disorder and started maintenance hemodialysis between June 2009 and April 2014. BIA was performed within the 1(st) week from the start of hemodialysis. The patients were classified into 2 groups based on volume status measured by the body composition monitor (BCM; Fresenius): an overhydrated group [OG; overhydration/extracellular water (OH/ECW) >15%] and a nonoverhydrated group (NOG; OH/ECW ≤15%).
  
  
  RESULTS
  A total of 344 patients met the inclusion criteria. Of these, 252 patients (73.3%) were categorized into the OG and 92 patients (26.7%) into the NOG. Age- and sex-matching patients were selected with a rate of 2:1. Finally, 160 overhydrated patients and 80 nonoverhydrated patients were analyzed. Initial levels of hemoglobin and serum albumin were significantly lower in the OG. During follow-up, 43 patients from the OG and 7 patients from the NOG died (median follow-up duration, 24.0 months). The multivariate-adjusted all-cause mortality was significantly increased in the OG (odds ratio, 2.569; P = 0.033) and older patients (odds ratio, 1.072/y; P < 0.001). No significant difference of all-cause or disease-specific admission rate was observed between the 2 groups.
  
  
  CONCLUSIONS
  The ratio of OH/ECW volume measured with body composition monitor is related to the overall survival of end-stage renal disorder patients who started maintenance hemodialysis.
authors.affiliation: Department of Internal Medicine, Chungnam National University Hospital, Daejeon, Korea.
authors.forename: Ye Jin
authors.initials: YJ
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Chungnam National University Hospital, Daejeon, Korea.
authors.forename: Hong Jae
authors.initials: HJ
authors.lastname: Jeon
authors.affiliation: Department of Internal Medicine, Chungnam National University Hospital, Daejeon, Korea.
authors.forename: Yoo Hyung
authors.initials: YH
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Chungnam National University Hospital, Daejeon, Korea.
authors.forename: Jaewoong
authors.initials: J
authors.lastname: Jeon
authors.affiliation: Department of Internal Medicine, Chungnam National University Hospital, Daejeon, Korea.
authors.forename: Young Rok
authors.initials: YR
authors.lastname: Ham
authors.affiliation: Department of Internal Medicine, Chungnam National University Hospital, Daejeon, Korea.
authors.forename: Sarah
authors.initials: S
authors.lastname: Chung
authors.affiliation: Department of Internal Medicine, Chungnam National University Hospital, Daejeon, Korea.
authors.forename: Dae Eun
authors.initials: DE
authors.lastname: Choi
authors.affiliation: Department of Internal Medicine, Chungnam National University Hospital, Daejeon, Korea.
authors.forename: Ki Ryang
authors.initials: KR
authors.lastname: Na
authors.affiliation: Department of Internal Medicine, Chungnam National University Hospital, Daejeon, Korea.
authors.forename: Kang Wook
authors.initials: KW
authors.lastname: Lee
keywords: Bioimpedance analysis; Extracellular water; Hemodialysis; Hydration; Mortality