Percent body fat measured by BIA and DEXA in obese, African-American adolescent girls

Abstract

OBJECTIVE:To compare the estimation of body fat between bioelectrical impedance analysis (BIA) and dual energy X-ray absorptiometry (DEXA) in overweight, African-American female adolescents. SUBJECTS: In total, 54 African-American adolescent female subjects were recruited for Study 1. Each adolescent's body mass index was greater than the 85th percentile and their average body fat was 45% according to DEXA. A total of 26 AfricanAmerican adolescent female subjects were available for Study 2, and had an average body fat of 26% according to DEXA. MEASUREMENTS: Percent body fat was measured by DEXA and BIA. Seven different BIA equations were tested. Both sets of data were analyzed using Bland-Altman regression analyses, utilizing percent body fat measured by DEXA as the criterion. RESULTS: The Kushner equation provided estimates that were unaffected by body fat in both studies. Estimates were unbiased when applied to the exclusively overweight sample and biased when utilized with the separate sample of normal weight and obese girls. The remaining equations were biased, provided inconsistent estimates across body weight, or were biased and provided inconsistent estimates. Ethnicity-specific and ethnicity-combined equations performed similarly in the obese sample, but became more disparate when applied to a sample encompassing a wider body weight range. The limits of agreement between all BIA equations and the DEXA estimates ranged from 6 to 9%. CONCLUSION: The study suggests that the Kushner BIA equation is appropriate for use with African-American female adolescents across the weight spectrum, while the majority of BIA equations underestimated percent body fat as body fat increased.

Evidence of metabolic syndrome in lean children with premature pubarche at diagnosis

“…In this study, we used supine DEXA to assess body composition [43]. Along with underwater weighing and isotope dilution, DEXA is considered the most accurate method for measurement of body composition [44]. To provide consistency in body composition measurements, all PP subjects and controls in our study underwent DEXA scan measurement of body composition in supine position.…”

Percentage of Body Fat Assessment Using Bioelectrical Impedance Analysis and Dual-Energy X-ray Absorptiometry in a Weight Loss Program for Obese or Overweight Chinese Adults

“…One study [29] involves a cross-sectional investigation stratified by gender and the other [36] uses a longitudinal study on Korean women. Most of the studies have been conducted on Caucasians [26], [28], [30]–[32], [34] and African-Americans [27], [33]. Several studies have considered only women [27], [30], [32], [33], [36] or adolescents [26], [27].…”

“…Most of the studies have been conducted on Caucasians [26], [28], [30]–[32], [34] and African-Americans [27], [33]. Several studies have considered only women [27], [30], [32], [33], [36] or adolescents [26], [27]. Longitudinal studies [30], [34]–[37] have also been performed, in which two studies have used weight-loss programs without randomization [34], [36].…”

Fuzzy logic as a decision-making support system for the indication of bariatric surgery based on an index (MAFOI) generated by the association between body fat and body mass index.

“…Hence, the BIA measures the body composition indirectly and is based on the electrical-conductivity principle and its stable relation with the body's liquid. It also uses the resistance, the reactance, and the phase angle as bioelectrical parameters 48,[50][51][52][53][54][55] . Resistance is the opposition offered by the body content to the alternated electrical current and is inversely proportional to the quantity of water and electrolytes present in the tissues.…”

“…The BIA's predictive accuracy can be influenced by the degree of body fat, age, gender, ethnic characteristics, diseases that alter the body type and factors that modify the hydroelectrolytic composition 53 . In order to clarify conflicting results, we used predictive equations that were adequate to the population under study 50,[48][49][50][51][52][53][54][55] .…”