The significance of measuring body fat percentage determined by bioelectrical impedance analysis for detecting subjects with cardiovascular disease risk factors.

BACKGROUND: Body fat percentage (BF%) determined by bioelectrical impedance analysis is widely used at home and in medical check-ups. However, the clinical significance of measuring BF% has not been studied in detail. METHODS AND RESULTS: A cross-sectional study was carried out on a cohort of 10,774 middle-aged Japanese men who had undergone an annual check-up in 2008. Cut-off points were evaluated for body mass index (BMI), waist circumference (WC), and BF% for detecting participants with cardiovascular disease (CVD) risk factors (diabetes mellitus, hypertension, dyslipidemia), and effectiveness compared for each marker's cut-off point. Additionally, the effects of smoking on cut-off points were evaluated. The cut-off points of BMI, WC, and BF% for detecting participants with 1 or more CVD risk factors were 22.7kg/m(2), 81.4cm, and 20.3%, respectively. The cut-off points of BF% for 1 or more CVD risk factors classified 3.43% more subjects into correct categories than those of BMI (P<0.001). The cut-off points of BMI, WC, and BF% for detecting individuals with 3 CVD risk factors in current smokers were 24.9kg/m(2), 87.8cm, and 23.7%, while those in non-smokers were 23.3kg/m(2), 83.9cm, and 22.3%, respectively. CONCLUSIONS: BF% could be more effective in detecting individuals with early stage CVD risk accumulation than BMI. The cut-off points for current smokers were lower than those for non-smokers in all markers.