title: Body composition and energy expenditure of patients with chronic cardiac failure.
abstract: BACKGROUND
  Patients with acute cardiac failure have excess body water, and it is commonly assumed that this is also so in patients with stable chronic cardiac failure (CCF).
  
  
  METHODS
  To investigate this, we measured total body water (TBW) using stable isotope dilution and single-frequency bioelectrical impedance (BIA), and also extracellular volume (ECV) using bromide dilution in 12 patients with CCF and eight matched control subjects.
  
  
  RESULTS
  TBW [kg(-1) bodyweight] was similar in the two groups [median 18O dilution 53.2% (range 46.5-57.1%) in patients vs. 54.8% (47.9-62.7) in control subjects; BIA 56.6% (42.7-73.1) vs. 58.0% (52.0-68.6)]. ECV was also similar in the two groups [0.25 Lkg(-1) (0.20-0.29) vs. 0.25 (0.19-0.35)]. There was a strong correlation between stable isotope and BIA measurements of TBW for all subjects (r = 0.76), but BIA overestimated TBW by a mean difference of 2.4 kg (limits of agreement of -4.1 kg to +8.9 kg). Body fat content was similar in the two groups, whether measured by skinfold anthropometry, whole-body densitometry or by 18O dilution. Resting energy expenditure (REE), calculated from indirect calorimetry, and total energy expenditure (TEE), calculated from the ratio of 2H to 18O elimination rate after drinking doubly labelled water, were also similar in the two groups.
  
  
  CONCLUSIONS
  It is concluded that the patients with stable CCF in this study had normal ECV and TBW, and so excess body water did not account for their persistent symptoms.
authors.affiliation: Royal Victoria Hospital, Belfast, UK.
authors.forename: I C
authors.initials: IC
authors.lastname: Steele
authors.forename: I S
authors.initials: IS
authors.lastname: Young
authors.forename: H P
authors.initials: HP
authors.lastname: Stevenson
authors.forename: S
authors.initials: S
authors.lastname: Maguire
authors.forename: M B
authors.initials: MB
authors.lastname: Livingstone
authors.forename: M
authors.initials: M
authors.lastname: Rollo
authors.forename: C
authors.initials: C
authors.lastname: Scrimgeour
authors.forename: M J
authors.initials: MJ
authors.lastname: Rennie
authors.forename: D P
authors.initials: DP
authors.lastname: Nicholls
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001823:Body Composition; D001834:Body Water; D001965:Bromides; D002908:Chronic Disease; D003720:Densitometry; D003903:Deuterium; D017097:Electric Impedance; D004734:Energy Metabolism; D005110:Extracellular Space / Q000378:metabolism; D006333:Heart Failure / Q000097:blood / Q000503:physiopathology* / Q000652:urine; D006801:Humans; D008297:Male; D008875:Middle Aged; D010103:Oxygen Isotopes; D017680:Potassium Compounds; D015203:Reproducibility of Results
chemical_list: D001965:Bromides; D010103:Oxygen Isotopes; D017680:Potassium Compounds; D003903:Deuterium; C039004:potassium bromide