Anthropometric indices to assess body-fat changes during a multidisciplinary obesity treatment in adolescents: EVASYON Study

Abstract

The main objectives of weight loss interventions in children and adolescents are to decrease fat mass while maintaining fat-free mass. Several methods are available to assess childhood and adolescence obesity, such as weight and height, bioelectrical impedance, skin-fold thickness measurements and other laboratory methods. The aim was to assess simple anthropometric indices as predictors of body-fat changes, using dual-energy X-ray absorptiometry measurements as reference method. Multi-intervention approach (diet, physical activity and psychological support in a family-group-based treatment) was implemented with a one-year follow-up in 13-to-16-year-old overweight or obese Spanish adolescents. A total of 83 adolescents were recruited from Granada and Zaragoza, males (n = 43) (31.6 kg/m(2)) and females (n = 40) (32.0 kg/m(2)). We measured body composition with anthropometry and dual-energy X-ray absorptiometry. All measurements were made at baseline, and after 2 and 13 months. Random coefficient regression model was used to calculate the proportion of body composition changes during follow-up that would be explained by simple body composition indices based on anthropometric measures. After controlling for age and Tanner stage, body mass index explained 76.5% of body composition changes in males and 90.1% in females, while fat mass index (assessed by skin-folds) explained 78.9% of body composition changes in males and 84.0% of body composition changes in females. In conclusion, we found that BMI was a good indicator of body fat composition changes in children and adolescents, although FMI assessed by anthropometry was also a good indicator.