[A new simple method for estimating trunk and visceral fat by bioelectrical impedance: comparison with magnetic resonance imaging and dual X-ray absorptiometry in Czech adolescents].

Background: The enlargement of visceral fat (VF) in abdominal obesity is associated with increased cardiometabolic health risks in both adults and adolescents. A precise measurement of VF by sophisticated methods as computed tomography (CT) and magnetic resonance imaging (MRI) cannot be applied in routine clinical practice. The aim of our study was to compare estimates on visceral and trunk fat in adolescents obtained by a new bioimpedance analysis instrument (BIA)--Tanita AB-140 ViScan--with those obtained by MRI, dual X-ray absorptiometry (DEXA) and anthropometry.

Methods And Results: Investigated cohort: 39 adolescent secondary school students; median (lower quartile; upper quartile)--age: 16.4 (15.4; 17.4) years; body weight: 63.8 (54.1; 79.0) kg; BMI: 21.4 (19.5; 27.4) kg/m2. Investigated parameters: BMI, body circumferences and sagittal abdominal diameter (SAD), trunk, visceral and subcutaneous fat determined by BIA, MRI and DEXA.

Statistics: Spearman's correlations. The assessment of trunk fat by BIA correlated with DEXA estimates (r = 0.979, p < 0.0001) and with abdominal fat measured by MRI (r = 0.930, p < 0.0001). The visceral fat amount derived from abdominal BIA exhibited lower, however significant correlation with visceral fat determined by MRI (r = 0.791, p < 0.001). The visceral fat area presumed by abdominal BIA significantly correlated with anthropometric parameters as abdominal circumference (r = 0.923, p < 0.0001), waist circumference (r = 0.913, p < 0.0001) and SAD (r= 0.891, p < 0.0001).

Conclusions: The new method estimating abdominal fat by BIA represents a reliable tool for clinical evaluation of the trunk fat in adolescents. However, its advantages over anthropometric measurements in evaluation of VF require further validation studies.