Threshold values of visceral fat and waist girth in Japanese obese children

Background: In order to define the diagnostic criteria for visceral adipose tissue (VAT) accumulation and abdominal obesity in Japanese youths, a cross-sectional, multicenter study was conducted. Methods: Subjects were 194 boys and 96 girls ranging in age from 6 to 15 years. Obese youths were classified according to the occurrence of abnormal values in serum triglyceride, alanine aminotransferase or insulin level. A threshold value of each criterion was calculated, using the analysis of receiver operating characteristic (ROC) curve. The areas of total abdominal adipose tissue (AT), VAT and subcutaneous adipose tissue (SAT) were estimated by single slice computed tomography at the level of umbilicus. Results: VAT area was greater in boys than it was in girls. The critical values for VAT area and waist circumference in all subjects were 54.8 cm(2) and 83.5 cm, respectively. The values for the area under the ROC curves were VAT area > total AT area > waist circumference > SAT area > percentage overweight > percentage body fat. The sensitivity and specificity for VAT area were 90.5 and 79.5%, respectively. Those for waist circumference were high enough (> 70%) for clinical use. In the linear regression analysis assigning VAT area as an independent variable and waist circumference as a dependent variable, the expected value for the waist circumference was 82 cm. Conclusion: In Japanese obese youths ranging in age from 6 to 15 years, the diagnostic criteria for the waist circumference was 82 cm, and that for VAT area was 55 cm(2).