title: Comparison of body adiposity index (BAI) and BMI with estimations of % body fat in clinically severe obese women.
abstract: OBJECTIVE
  Body adiposity index (BAI), a new surrogate measure of body fat (hip circumference/(height(1.5) - 18)), has been proposed as an alternative to body mass index (BMI). We compared BAI with BMI, and each of them with laboratory measures of body fat-derived from bioimpedance analysis (BIA), air displacement plethysmography (ADP), and dual-energy X-ray absorptiometry (DXA) in clinically severe obese (CSO) participants.
  
  
  METHODS
  Nineteen prebariatric surgery CSO, nondiabetic women were recruited (age = 32.6 ± 7.7 SD; BMI = 46.5 ± 9.0 kg/m(2) ). Anthropometrics and body fat percentage (% fat) were determined from BIA, ADP, and DXA. Scatter plots with lines of equality and Bland-Altman plots were used to compare BAI and BMI with % fat derived from BIA, ADP, and DXA. BAI and BMI correlated highly with each other (r = 0.90, P < 0.001).
  
  
  RESULTS
  Both BAI and BMI correlated significantly with % fat from BIA and ADP. BAI, however, did not correlate significantly with % fat from DXA (r = 0.42, P = 0.08) whereas BMI did (r = 0.65, P = 0.003). BMI was also the single best predictor of % fat from both BIA (r(2) = 0.80, P < 0.001) and ADP (r(2) = 0.65, P < 0.001). The regression analysis showed that the standard error of the estimate (SEE), or residual error around the regression lines, was greater for BAI comparisons than for BMI comparisons with BIA, ADP, and DXA. Consistent with this, the Bland and Altman plots indicated wider 95% confidence intervals for BAI difference comparisons than for BMI difference comparisons for their respective means for BIA, ADP, and DXA.
  
  
  CONCLUSIONS
  Thus, BAI does not appear to be an appropriate proxy for BMI in CSO women.
authors.affiliation: New York Obesity Nutrition Research Center, Medical Service, St Luke's-Roosevelt Hospital Center, New York, New York, USA.
authors.forename: Allan
authors.initials: A
authors.lastname: Geliebter
authors.forename: Deniz
authors.initials: D
authors.lastname: Atalayer
authors.forename: Louis
authors.initials: L
authors.lastname: Flancbaum
authors.forename: Charlisa D
authors.initials: CD
authors.lastname: Gibson
mesh_terms: D015502:Absorptiometry, Photon; D000273:Adipose Tissue / Q000737:chemistry*; D050154:Adiposity; D000328:Adult; D050110:Bariatric Surgery; D001823:Body Composition; D015992:Body Mass Index; D017097:Electric Impedance; D005260:Female; D006801:Humans; D016014:Linear Models; D008875:Middle Aged; D009765:Obesity / Q000378:metabolism* / Q000601:surgery; D010991:Plethysmography; D055815:Young Adult