title: Bioimpedance and bioimpedance vector analysis in patients with anorexia nervosa.
abstract: OBJECTIVE
  The utility of bioelectrical impedance analysis (BIA) in patients with anorexia nervosa (AN) is imperfectly defined. Furthermore, any advantage accrued by BIA with vector analysis (BIVA) is unknown.
  
  
  METHODS
  We conducted a retrospective analysis of 57 women with AN admitted to our service who underwent BIA and BIVA. Twenty-seven women were observed during short-term (3 weeks) and 13 women during longer-term (3 months) weight gain.
  
  
  RESULTS
  Bioelectrical impedance analysis produced implausible results in 47% of the patients. BIVA demonstrated low body cell mass and highly variable extracellular water (ECW) volume, ranging from volume contraction to volume expansion on admission and during treatment. BIVA suggested that short-term weight gain predominantly consisted of ECW volume, whereas longer-term weight gain resulted in increased hydrated body cell mass.
  
  
  CONCLUSIONS
  Conventional BIA has little utility in these patients. However, BIVA could be a suitable alternative in the medical management reflecting ECW volume changes and later genuine tissue mass increases.
authors.affiliation: Experimental and Clinical Research Center, a joint cooperation between the Charité Medical Faculty and the Max-Delbrück Center for Molecular Medicine, Charité University Clinic, Berlin, Germany. verena.haas@charite.de
authors.forename: Verena
authors.initials: V
authors.lastname: Haas
authors.forename: Andrea
authors.initials: A
authors.lastname: Riedl
authors.forename: Tobias
authors.initials: T
authors.lastname: Hofmann
authors.forename: Annette
authors.initials: A
authors.lastname: Nischan
authors.forename: Roland
authors.initials: R
authors.lastname: Burghardt
authors.forename: Michael
authors.initials: M
authors.lastname: Boschmann
authors.forename: Burghard
authors.initials: B
authors.lastname: Klapp
mesh_terms: D000328:Adult; D000856:Anorexia Nervosa / Q000175:diagnosis* / Q000503:physiopathology / Q000628:therapy; D001823:Body Composition / Q000502:physiology*; D015992:Body Mass Index; D016022:Case-Control Studies; D017097:Electric Impedance; D005260:Female; D006801:Humans; D008875:Middle Aged; D010992:Plethysmography, Impedance; D015203:Reproducibility of Results; D012189:Retrospective Studies