title: [Validation of body composition estimation equations by bioelectric impedance in postmenopausic women with metabolic syndrome].
abstract: BACKGROUND
  Postmenopausal women have excess adiposity due to the lack of estrogens, which is related with an increase in the prevalence of metabolic syndrome (MS) risk factors. Few equations have been developed to measure body fat mass (FM) by bioelectric impedance (BIA) for Mexican women and none of the existing equations have been evaluated in Mexican postmenopausal women with MS.
  
  
  METHODS
  We describe the association and agreement between two different BIA equations: NHANES III and Macias, et al. to estimate FM in 86 women (42-72 years old). Anthropometric and body composition measurements (BIA) were done in all women; FM was measured by densitometry (DXA). Mean differences by age group (< 55 years old and > or = 55 years old) (Student t test), correlations, simple linear regression models and agreement analysis (Bland-Altman method) were done.
  
  
  RESULTS
  The two equations showed underestimation of % FM compared to DXA. The equation that presents the greatest correlation and agreement with the gold standard is the NHANES equation, in both age groups.
  
  
  CONCLUSIONS
  The NHANES equation is valid to estimate FM in Mexican postmenopausal women with MS. We recommend the use of this equation in the clinical practice.
authors.affiliation: Departamento de Investigación en Nutrición, Subdirección de Investigación en Salud Pública, Instituto Nacional de Perinatología Isidro Espinosa de los Reyes, México, DF.
authors.forename: Margie
authors.initials: M
authors.lastname: Balas-Nakash
authors.forename: Jennifer
authors.initials: J
authors.lastname: Legorreta-Legorreta
authors.forename: Ameyalli
authors.initials: A
authors.lastname: Rodríguez-Cano
authors.forename: Rafael
authors.initials: R
authors.lastname: Aguilera-Pérez
authors.forename: Otilia
authors.initials: O
authors.lastname: Perichart-Perera
mesh_terms: D000273:Adipose Tissue / Q000473:pathology; D000328:Adult; D000368:Aged; D000465:Algorithms; D001823:Body Composition; D003720:Densitometry; D017097:Electric Impedance; D005260:Female; D006801:Humans; D024821:Metabolic Syndrome / Q000473:pathology*; D008875:Middle Aged; D017698:Postmenopause; D055105:Waist Circumference; D049629:Waist-Hip Ratio