Ultrasound Measurement of Total Body Fat in Obese Adolescents

• Published in: Annals of nutrition and metabolism 2010-01, Vol.56 (1), p.36-44
• Main Authors: Pineau, Jean-Claude, Lalys, Loïc, Bocquet, Michel, Guihard-Costa, Anne-Marie, Polak, Michel, Frelut, Marie-Laure, Peres, Gilbert, Dabbas-Tyan, Myriam
• Format: Article
• Language: English
• Subjects: Absorptiometry, Photon; Adipose Tissue - diagnostic imaging; Adolescent; Adolescents; Biological anthropology; Body Composition; Body fat; Body Mass Index; Body weight; Child; Female; Females; Humanities and Social Sciences; Humans; Male; Males; Obesity - diagnostic imaging; Obesity - therapy; Observer Variation; Original Paper; Reproducibility of Results; Skinfold Thickness; Ultrasonography - instrumentation; Ultrasonography - methods; Weight Loss; Young Adult
• ISSN: 0250-6807; 1421-9697
• DOI: 10.1159/000265849

Background/Aims: To compare body fat (BF) measurements obtained with a new ultrasound method with those assessed by dual-energy X-ray absorptiometry (DEXA) in obese adolescents. Methods: In 94 adolescents (57 females and 37 males) aged 12–19 years and body mass index (BMI) exceeding 30 kg·m –2 , the z-score BMI for age was 6.7 (adolescent girls) and 6.6 (adolescent boys) >97th percentile. BF was measured using DEXA and a method based on ultrasound measurements, body weight, height, abdominal circumference and mid-thigh circumference. Results: Obesity class I was noted in 39%, II in 28% and III in 33% of the patients. BF by ultrasound correlated closely with BF by DEXA, in both females (r = 0.958) and males (r = 0.981), with standard errors of the estimates (SEE) being 2.9 and 2.5 kg, respectively. The ultrasound method was more accurate than the skinfold technique (n = 24; SEE: 2.2 vs. 6.5 kg, respectively). In 13 adolescents who had marked weight loss after 6 months of treatment, the decrease in DEXA-measured BF correlated closely with the decrease in ultrasound-measured BF (r = 0.95). Conclusions: Our innovative portable ultrasound technique has advantages in terms of reliability, reproducibility, accuracy and costs for screening and monitoring obese adolescents. A patent application has been submitted. Our method should prove valuable for epidemiological studies.