THE PREDICTION OF EXTRACELLULAR AND TOTAL-BODY WATER FROM BIOELECTRIC IMPEDANCE IN A NON-CAUCASIAN POPULATION FROM CENTRAL-ASIA

The availability of only a small number of studies on bioelectric impedance analysis (BIA) in non-Caucasian ethnic groups appears to limit reliable utilization of this method in anthropological field studies. In this study, 28 male Turkish-Mongolian subjects native of Kazakhstan (Central Asia) underwent total body water (TBW) and extracellular water (ECW) assessment by deuterium oxide (D2O) and sodium bromide (NaBr) dilution respectively. Bioelectric impedance (BI) was recorded at multiple frequencies. ECW and TBW were calculated from BI at 1 and 100 kHz respectively by applying formulae developed on a sample of Caucasian subjects with a hydration status similar to that of the study population. TBW predicted from BI at 100 kHz (37.5+/-3.31)was highly correlated and not significantly different from that obtained by D2O dilution (39.0+/-4.11, r=0.894, p<0.0001, SEE=1.91). Similarly, ECW predicted from BI at 1 kHz(15.1+/-1.2]) was highly correlated and not significantly different from that obtained by NaBr dilution (15.0+/-1.61, r=0.847, p<0.0001, SEE=0.81). It is concluded that selected predictive formulae developed on Caucasian subjects may provide a precise and accurate assessment of ECW and TBW in Turkish-Mongolian populations.