BMI and an anthropometry-based estimate of fat mass percentage are both valid discriminators of cardiometabolic risk: a comparison with DXA and bioimpedance.
OBJECTIVE
To determine whether categories of obesity based on BMI and an anthropometry-based estimate of fat mass percentage (FM% equation) have similar discriminative ability for markers of cardiometabolic risk as measurements of FM% by dual-energy X-ray absorptiometry (DXA) or bioimpedance analysis (BIA).


METHODS
A study of 40-79-year-old male (n = 205) and female (n = 388) Finns. Weight, height, blood pressure, triacylglycerols, HDL cholesterol, and fasting blood glucose were measured. Body composition was assessed by DXA and BIA and a FM%-equation.


RESULTS
For grade 1 hypertension, dyslipidaemia, and impaired fasting glucose >6.1 mmol/L, the categories of obesity as defined by BMI and the FM% equation had 1.9% to 3.7% (P < 0.01) higher discriminative power compared to DXA. For grade 2 hypertension the FM% equation discriminated 1.2% (P = 0.05) lower than DXA and 2.8% (P < 0.01) lower than BIA. Receiver operation characteristics confirmed BIA as best predictor of grade 2 hypertension and the FM% equation as best predictor of grade 1 hypertension. All other differences in area under curve were small (≤0.04) and 95% confidence intervals included 0.


CONCLUSIONS
Both BMI and FM% equations may predict cardiometabolic risk with similar discriminative ability as FM% measured by DXA or BIA.
Department of Health Sciences, University of Jyväskylä, P.O. BOX 35 (L), 40014 Jyväskylä, Finland ; Kuopio Research Institute of Exercise Medicine, Haapaniementie 16, 70100 Kuopio, Finland ; Department of Public Health and Clinical Medicine, Occupational and Environmental Medicine, Umeå University, 901 85 Umeå, Sweden.
Benno
B
Krachler
Department of Health Sciences, University of Jyväskylä, P.O. BOX 35 (L), 40014 Jyväskylä, Finland ; Department of Preventive Medicine, University of TN Health Science Center, Memphis, Tennessee 38163, USA.
Eszter
E
Völgyi
Kuopio Research Institute of Exercise Medicine, Haapaniementie 16, 70100 Kuopio, Finland ; Department of Clinical Physiology and Nuclear Medicine, Kuopio University Hospital, 70211 Kuopio, Finland.
Kai
K
Savonen
Department of Preventive Medicine, University of TN Health Science Center, Memphis, Tennessee 38163, USA.
Frances A
FA
Tylavsky
Department of Medical Rehabilitation, Oulu University Hospital and Institute of Health Sciences, University of Oulu, 90029 Oulu, Finland.
Markku
M
Alén
Department of Health Sciences, University of Jyväskylä, P.O. BOX 35 (L), 40014 Jyväskylä, Finland ; School of Kinesiology, Shanghai University of Sport, Shanghai 200438, China.
Sulin
S
Cheng
D015502:Absorptiometry, Photon; D000273:Adipose Tissue; D000328:Adult; D000368:Aged; D000886:Anthropometry; D001823:Body Composition; D015992:Body Mass Index; D017097:Electric Impedance; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000473:pathology*; D011237:Predictive Value of Tests; D012372:ROC Curve; D015203:Reproducibility of Results