title: Nutritional assessment: lean body mass depletion at hospital admission is associated with an increased length of stay.
abstract: BACKGROUND
  Low fat-free mass may be an independent risk factor for malnutrition that results in an increased length of hospital stay (LOS).
  
  
  OBJECTIVE
  The objectives were to compare differences in fat-free mass and fat mass at hospital admission between patients and healthy control subjects and to determine the association between these differences and the LOS.
  
  
  METHODS
  Patients (525 men, 470 women) were prospectively recruited at hospital admission. Height-corrected fat-free mass and fat mass (fat-free-mass index or fat-mass index; in kg/m2) were determined in patients at admission by bioelectrical impedance analysis and were compared with values for sex-, age-, and height-matched control subjects. Patients were classified as well-nourished, moderately depleted, or severely depleted on the basis of a Subjective Global Assessment questionnaire and a body mass index (in kg/m2) < or > 20.
  
  
  RESULTS
  Low fat-free mass was noted in 37% and 55.6% of patients hospitalized 1-2 d and > 12 d, respectively. The odds ratios were significant for fat-free-mass index and were higher in patients with a LOS of > 12 d [men (odds ratio: 5.6; 95% CI: 3.1, 10.4), women (4.4; 2.3, 8.7)] than in those with a LOS of 1-2 d [men (3.3; 2.2, 5.0), women (2.2; 1.6, 3.1)]. Severe nutritional depletion was significantly associated only with a LOS > 12 d.
  
  
  CONCLUSIONS
  Fat-free mass and fat-free-mass index were significantly lower in patients than in control subjects. Because the fat-free-mass index is significantly associated with an increased LOS, provides nutritional assessment information that complements that from a Subjective Global Assessment questionnaire, and is a more sensitive determinant of the association of fat-free mass with LOS than is a weight loss > 10% or a body mass index < 20, it should be used to evaluate nutritional status.
authors.affiliation: Clinical Nutrition department, Geneva University Hospital, Geneva, Switzerland. claude.pichard@medecine.unige.ch
authors.forename: Claude
authors.initials: C
authors.lastname: Pichard
authors.forename: Ursula G
authors.initials: UG
authors.lastname: Kyle
authors.forename: Alfredo
authors.initials: A
authors.lastname: Morabia
authors.forename: Arnaud
authors.initials: A
authors.lastname: Perrier
authors.forename: Bernard
authors.initials: B
authors.lastname: Vermeulen
authors.forename: Pierre
authors.initials: P
authors.lastname: Unger
mesh_terms: D000273:Adipose Tissue; D000368:Aged; D015992:Body Mass Index; D016022:Case-Control Studies; D017097:Electric Impedance; D005260:Female; D006760:Hospitalization; D006801:Humans; D007902:Length of Stay; D008297:Male; D044342:Malnutrition / Q000378:metabolism*; D008875:Middle Aged; D015596:Nutrition Assessment; D011446:Prospective Studies; D012044:Regression Analysis