title: Association of Fluid Status and Body Composition with Physical Function in Patients with Chronic Kidney Disease.
abstract: BACKGROUND
  Impairment of physical function and abnormal body composition are the major presentations in patients with chronic kidney disease (CKD). The aim of this study is to investigate the relationship between body composition and physical function in CKD patients.
  
  
  METHODS
  This cross-sectional study enrolled 172 of CKD stages 1-5 from February 2013 to September 2013. Handgrip strength (upper extremity muscle endurance), 30-second chair-stand test (lower extremity muscle endurance) and 2-minute step test (cardiorespiratory endurance) were used as indices of physical function. Body composition, including fluid status (extracellular water/total body water, ECW/TBW), lean tissue index (LTI), and fat tissue index (FTI), was measured using a bioimpedance spectroscopy method.
  
  
  RESULTS
  All patients with high ECW/TBW had lower handgrip strength and 30-second chair-stand than those with low ECW/TBW (P<0.001 and P = 0.002). CKD patients with high FTI had lower handgrip strength and 30-second chair-stand than those with low FTI (P<0.001 and P = 0.002). These patients with low LTI had lower handgrip strength than those with high LTI (P = 0.04). In multivariate analysis, high ECW/TBW was positively associated with decreased handgrip strength (β = -41.17, P = 0.03) in CKD patients. High FTI was significantly correlated with decreased times of 30-second chair-stand (β = -0.13, P = 0.01). There was no significant relationship between body composition and 2-minute step test.
  
  
  CONCLUSIONS
  Our results show a significant association of impaired upper and lower extremity muscle endurance with high fluid status and fat tissue. Evaluation of body composition may assist in indentifying physical dysfunction earlier in CKD patients.
authors: Department of Nursing, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan.
authors: Shih-Ming
authors: SM
authors: Hsiao
authors: Division of General Medicine, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan.|Division of Nephrology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan.
authors: Yi-Chun
authors: YC
authors: Tsai
authors: Graduate of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.|Department of Occupational Therapy, College of Health Sciences, Kaohsiung Medical University, Kaohsiung, Taiwan.
authors: Hui-Mei
authors: HM
authors: Chen
authors: Division of Nephrology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan.|Faculty of Renal Care, Kaohsiung Medical University, Kaohsiung, Taiwan.
authors: Ming-Yen
authors: MY
authors: Lin
authors: Division of Nephrology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan.|Faculty of Renal Care, Kaohsiung Medical University, Kaohsiung, Taiwan.
authors: Yi-Wen
authors: YW
authors: Chiu
authors: Department of Nursing, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan.
authors: Tzu-Hui
authors: TH
authors: Chen
authors: Department of Nursing, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan.
authors: Shu-Li
authors: SL
authors: Wang
authors: Department of Nursing, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan.
authors: Pei-Ni
authors: PN
authors: Hsiao
authors: Department of Nursing, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan.
authors: Lan-Fang
authors: LF
authors: Kung
authors: Division of Nephrology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan.|Faculty of Renal Care, Kaohsiung Medical University, Kaohsiung, Taiwan.|Institute of Population Sciences, National Health Research Institutes, Miaoli, Taiwan.
authors: Shang-Jyh
authors: SJ
authors: Hwang
authors: Graduate of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.|Department of Psychiatry, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan.
authors: Mei-Feng
authors: MF
authors: Huang
authors: Graduate of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.|Department of Psychiatry, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan.
authors: Yi-Chun
authors: YC
authors: Yeh
authors: Graduate of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.|Department of Psychiatry, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan.
authors: Cheng-Sheng
authors: CS
authors: Chen
authors: Division of Nephrology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan.|Faculty of Renal Care, Kaohsiung Medical University, Kaohsiung, Taiwan.
authors: Mei-Chuan
authors: MC
authors: Kuo
mesh_terms: D000368:Aged; D001823:Body Composition / Q000502:physiology*; D001826:Body Fluids / Q000502:physiology*; D001834:Body Water; D015331:Cohort Studies; D005260:Female; D018737:Hand Strength; D006801:Humans; D008297:Male; D008875:Middle Aged; D051436:Renal Insufficiency, Chronic / Q000503:physiopathology*