Tohoku J. Exp. Med., 2008, 214(2)

Development of a New Method for Estimating Visceral Fat Area with Multi-Frequency Bioelectrical Impedance

MASATO NAGAI,¹ HIDEAKI KOMIYA,^1,2 YUTAKA MORI,³ TERUO OHTA,⁴ YASUHIRO KASAHARA⁵ and YOSHIO IKEDA⁵

¹Department of Exercise Physiology, Utsunomiya University, Tochigi, Japan
²Department of Public Health, Dokkyo University, School of Medicine, Tochigi, Japan
³Department of Internal Medicine, National Hospital Organization Utsunomiya National Hospital, Tochigi, Japan
⁴Department of Internal Medicine, Sirasawa Hospital, Tochigi, Japan
⁵TANITA Body Weight Scientific Institute, Tokyo, Japan

Excessive visceral fat area (VFA) is a major risk factor in such conditions as cardiovascular disease. In assessing VFA, computed tomography (CT) is adopted as the gold standard; however, this method is cost intensive and involves radiation exposure. In contrast, the bioelectrical impedance (BI) method for estimating body composition is simple and noninvasive and thus its potential application in VFA assessment is being studied. To overcome the difference in obtained impedance due to measurement conditions, we developed a more precise estimation method by selecting the optimum body posture, electrode arrangement, and frequency. The subjects were 73 healthy volunteers, 37 men and 36 women, who underwent CT scans to assess VFA and who were measured for anthropometry parameters, subcutaneous fat layer thickness, abdominal tissue area, and impedance. Impedance was measured by the tetrapolar impedance method using multi-frequency BI. Multiple regression analysis was conducted to estimate VFA. The results revealed a strong correlation between VFA observed by CT and VFA estimated by impedance (r = 0.920). The regression equation accurately classified VFA ≥ 100 cm² in 13 out of 14 men and 1 of 1 woman. Moreover, it classified VFA ≥ 100 cm² or < 100 cm² in 3 out of 4 men and 1 of 1 woman misclassified by waist circumference (W) which was adopted as a simple index to evaluate VFA. Therefore, using this simple and convenient method for estimating VFA, we obtained an accurate assessment of VFA using the BI method.

keywords —— bioelectrical impedance; visceral fat; computed tomography; body composition; waist circumference.

© 2008 Tohoku University Medical Press

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Tohoku J. Exp. Med., 2008, 214, 105-112

Correspondence: Hideaki Komiya, Department of Exercise Physiology, Utsunomiya University, 350 Mine-machi Utsunomiya city, Tochigi 321-8505, Japan.

e-mail: komiya@cc.utsunomiya-u.ac.jp