Dual-energy X-ray absorptiometry for body composition estimation in Chinese women.
OBJECTIVE
To determine whether dual-energy X-ray absorptiometry (DXA) is a valid method for body composition assessment of obese and non-obese subjects.


METHODS
Cross-sectional study.


METHODS
Chinese women living in Hong Kong; 66 of 91 subjects had body mass index (BMI) of >25 kg/m2.


METHODS
Anthropometrics, including body weight, body height, waist and hip girth. Percentage body fat (%BF) and fat-free mass (FFM) from DXA (Hologic 2000 plus, Enhanced Array Whole Body Version 5.63) were compared with that based on a tracer dose of deuterium oxide for the determination of total body water (TBW).


RESULTS
In both obese and non-obese subjects, FFMDXA was similar to FFMTBW. The Bland and Altman-type analysis indicated that comparable between-methods differences (mean bias) and limits of agreement were obtained in obese and non-obese subjects for FFM (0.4, between -4.4 and 5.2 kg vs 0.5, between -3.1 and 4.1 kg) and %BF (-0.6, between -7.6 and 6.4% vs -1.2, between -8.6 and 6.2%). The %BF bias was independent of age, BMI, hip circumference, and waist-to-hip ratio, but correlated with waist girth (r=0.24, P=0. 021).


CONCLUSIONS
The sources of bias are methodological and anthropometric in nature. The between-methods differences, however, are small and clinically insignificant. DXA is a valid method for assessing the body composition of obese patients.


BACKGROUND
This study was supported by a HKU-CRCG grant.
He
M
M
Food and Nutritional Science Program, Department of Zoology University of Hong Kong, Hong Kong SAR, People's Republic of China.
Li
E T
ET
Kung
A W
AW
D015502:Absorptiometry, Photon / Q000379:methods; D000328:Adult; D000886:Anthropometry; D044466:Asian People; D001823:Body Composition; D001834:Body Water; D002681:China; D005260:Female; D006801:Humans; D008875:Middle Aged; D009765:Obesity