title: Extracellular volume expansion and the preservation of residual renal function in Korean peritoneal dialysis patients: a long-term follow up study.
abstract: BACKGROUND
  In chronic peritoneal dialysis patients, preservation of residual renal function (RRF) is a major determinant of patient survival, and maintaining sufficient intravascular volume has been hypothesized to be beneficial for the preservation of RRF. The present study aimed to test this hypothesis using multifrequency bioimpedence analyzer (MFBIA), in Korean peritoneal dialysis patients.
  
  
  METHODS
  A total of 129 patients were enrolled in this study. The baseline MFBIA was checked, and the patients were divided into the following two groups: group 1, extracellular water per total body water (ECW/TBW) < median, group 2, ECW/TBW > median. We followed up the patients, and then we analyzed the changes in the urine output (UO) and the solute clearance (weekly uKt/V) in each group. Data associated with patient and technical survivor were collected by medical chart review. The volume measurement was made using Inbody S20 equipment (Biospace, Seoul, Korea). We excluded the anuric patients at baseline.
  
  
  RESULTS
  The median value of ECW/TBW was 0.396. The mean patient age was 49.74 ± 10.01 years, and 62.1 % of the patients were male; most of the patients were on continuous ambulatory peritoneal dialysis (89.1 %). The mean dialysis vintage was 26.20 ± 28.71 months. All of the patients were prescribed hypertensive medication, and 48.5 % of the patients had diabetes. After 25.47 ± 6.86 months of follow up, ΔUO and Δweekly Kt/V were not significantly different in the two groups as follows: ΔUO (-236.07 ± 185.15 in group 1 vs -212.21 ± 381.14 in group 2, p = 0.756); Δ weekly Kt/v (-0.23 ± 0.43 in group 1 vs -0.29 ± 0.49 in group 2, p = 0.461). The patient and technical survivor rate was inferior in the group 2, and in the multivariable analysis, initial hypervolemia was an independent factor that predicts both of the patient mortality [HR 1.001 (1.001-1.086), p = 0.047] and the technical failure [HR 1.024 (1.001-1.048), p = 0.042].
  
  
  CONCLUSIONS
  Extracellular volume expansion, measured by MFBIA, does not help preserve residual renal function, and is harmful for the technical and patient survival in Korean peritoneal dialysis patients.
authors.affiliation: Department of Internal Medicine, Pusan National University School of Medicine, Pusan, South Korea.|Division of Nephrology, Biomedical Research Institute, Pusan National University Hospital, Gudeok-ro179, Seo-gu, Pusan, 602-739, South Korea.
authors.forename: Harin
authors.initials: H
authors.lastname: Rhee
authors.affiliation: Department of Nursing Service, Pusan National University School of Medicine, Pusan, South Korea.
authors.forename: Min Ja
authors.initials: MJ
authors.lastname: Baek
authors.affiliation: Department of Internal Medicine, Ulsan University Hospital, Ulsan, South Korea.
authors.forename: Hyun Chul
authors.initials: HC
authors.lastname: Chung
authors.affiliation: Department of Internal Medicine, Pusan National University School of Medicine, Pusan, South Korea.|Division of Nephrology, Biomedical Research Institute, Pusan National University Hospital, Gudeok-ro179, Seo-gu, Pusan, 602-739, South Korea.
authors.forename: Jong Man
authors.initials: JM
authors.lastname: Park
authors.affiliation: Department of Internal Medicine, Pusan National University School of Medicine, Pusan, South Korea.|Division of Nephrology, Biomedical Research Institute, Pusan National University Hospital, Gudeok-ro179, Seo-gu, Pusan, 602-739, South Korea.
authors.forename: Woo Jin
authors.initials: WJ
authors.lastname: Jung
authors.affiliation: Department of Internal Medicine, Pusan National University School of Medicine, Pusan, South Korea.|Division of Nephrology, Biomedical Research Institute, Pusan National University Hospital, Gudeok-ro179, Seo-gu, Pusan, 602-739, South Korea.
authors.forename: Soo Min
authors.initials: SM
authors.lastname: Park
authors.affiliation: Department of Internal Medicine, Pusan National University School of Medicine, Pusan, South Korea.|Division of Nephrology, Biomedical Research Institute, Pusan National University Hospital, Gudeok-ro179, Seo-gu, Pusan, 602-739, South Korea.
authors.forename: Jang Won
authors.initials: JW
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, Pusan National University School of Medicine, Pusan, South Korea.|Division of Nephrology, Biomedical Research Institute, Pusan National University Hospital, Gudeok-ro179, Seo-gu, Pusan, 602-739, South Korea.
authors.forename: Min Ji
authors.initials: MJ
authors.lastname: Shin
authors.affiliation: Department of Internal Medicine, Pusan National University School of Medicine, Pusan, South Korea.
authors.forename: Il Young
authors.initials: IY
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Pusan National University School of Medicine, Pusan, South Korea.|Division of Nephrology, Biomedical Research Institute, Pusan National University Hospital, Gudeok-ro179, Seo-gu, Pusan, 602-739, South Korea.
authors.forename: Sang Heon
authors.initials: SH
authors.lastname: Song
authors.affiliation: Department of Internal Medicine, Pusan National University School of Medicine, Pusan, South Korea.
authors.forename: Dong Won
authors.initials: DW
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, Pusan National University School of Medicine, Pusan, South Korea.
authors.forename: Soo Bong
authors.initials: SB
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, Pusan National University School of Medicine, Pusan, South Korea.|Division of Nephrology, Biomedical Research Institute, Pusan National University Hospital, Gudeok-ro179, Seo-gu, Pusan, 602-739, South Korea.
authors.forename: Ihm Soo
authors.initials: IS
authors.lastname: Kwak
authors.affiliation: Department of Internal Medicine, Pusan National University School of Medicine, Pusan, South Korea. sey-0220@hanmail.net.|Division of Nephrology, Biomedical Research Institute, Pusan National University Hospital, Gudeok-ro179, Seo-gu, Pusan, 602-739, South Korea. sey-0220@hanmail.net.
authors.forename: Eun Young
authors.initials: EY
authors.lastname: Seong
mesh_terms: D000328:Adult; D001823:Body Composition; D001834:Body Water / Q000378:metabolism*; D016009:Chi-Square Distribution; D017097:Electric Impedance; D005260:Female; D005500:Follow-Up Studies; D005919:Glomerular Filtration Rate; D006801:Humans; D053208:Kaplan-Meier Estimate; D007668:Kidney / Q000503:physiopathology*; D007674:Kidney Diseases / Q000175:diagnosis / Q000401:mortality / Q000503:physiopathology / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D010530:Peritoneal Dialysis / Q000009:adverse effects / Q000401:mortality; D016016:Proportional Hazards Models; D056910:Republic of Korea; D012189:Retrospective Studies; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome
keywords: Multifrequency bioimpedance analysis; Peritoneal dialysis; Residual renal function