Evaluation of a Foot-to-Foot Bioelectrical Impedance Analyzer in Pre-Menopausal Hispanic and Caucasian Women

Abstract

The prevalence of obesity and overweight continues to increase among adults and adolescents lending to the development of many chronic diseases including cardiovascular disease, diabetes, and high blood pressure. The accuracy of a foot-to-foot bioelectrical impedance analysis (BIA) system for estimating body composition has been previously reported. However, the validity of a foot-to-foot BIA system for assessing body fatness in Hispanic women has not been determined. PURPOSE: To determine the efficacy of a foot-to-foot bioelectrical impedance analyzer in pre-menopausal Hispanic and Caucasian women. METHODS: The body composition of 76 Hispanic [mean (SD) age: 42.7 (4.6) y; height: 161.3 (5.7) cm; body mass: 70.1 (15.1) kg] and 47 Caucasian [age: 43.8 (4.3) y; height: 165.5 (6.2) cm; body mass: 66.4 (12.1) kg] women was assessed by BIA, dual energy x-ray absorptiometry, and hydrostatic densitometry. Percentage of body fat (%BF) values measured by BIA were compared to %BF values derived from a 2-compartment (2-C) (Brozek, 1963) and a 3-compartment (3-C) (Lohman, 1986) model using a one-way ANOVA with repeated measures. RESULTS: There was no significant difference in body mass (P = 0.15) or age (P = 0.17) between the Hispanic and Caucasian women; although Caucasian women were significantly taller than Hispanic women (P <0.001). Mean (SD) %BF was significantly greater for Hispanic women than Caucasian women (P <0.001) but, no significant interaction was observed for race and %BF (P = 0.09). For Hispanic women, mean (SD) %BF values measured by BIA [36.3 (7.3) %] were similar to %BF derived from the 2-C model [35.3 (8.0) %] (P = 0.07) and BIA %BF values were significantly different than %BF derived from the 3-C model [38.2 (8.6) %] (P = 0.005). For Caucasian women, BIA measured %BF values [33.1 (7.9) %] were similar to those derived from the 2-C [32.1 (6.3) %] and 3-C [34.0 (7.5) %] model (P >0.40). CONCLUSION: For these data, BIA provided similar %BF values as the 2-C and 3-C models for Caucasian women. However, BIA %BF values were significantly different from 2-C and 3-C values for Hispanic women. These data may suggest the need to develop race specific equations for estimating body composition using foot-to-foot BIA. This study was supported by funds from NIH (P20-MD000548-01).