Intra-abdominal fat measurement by ultrasonography: association with anthropometry and metabolic syndrome in adolescents

Abstract Objective To associate intra-abdominal fat thickness measured by ultrasonography to the factors related to metabolic syndrome and to determine cutoff points of intra-abdominal fat measurement associated with a greater chance of metabolic syndrome in adolescents. Methods This was a cross-sectional study, with 423 adolescents from public schools. Intra-abdominal fat was measured by ultrasonography. Anthropometric data were collected, and biochemical analyses were performed. Results Intra-abdominal fat was measured by ultrasonography, showing a statistically significant association with the diagnosis of metabolic syndrome ( p  = 0.037), body mass index ( p p  = 0.012), decreased plasma HDL levels ( p  = 0.034), and increased systemic blood pressure values ( p  = 0.023). Cutoff values of intra-abdominal fat thickness measurements were calculated by ultrasound to estimate the individuals most likely to develop metabolic syndrome. In the logistic regression models, the cutoff values that showed the highest association with metabolic syndrome in males were 4.50, 5.35, 5.46, 6.24, and 6.50 cm for the ages of 14, 15, 16, 17, and 18/19 years, respectively. In the female gender, the cutoff values defined for the same age groups were 4.46, 4.55, 4.45, 4.90, and 6.46 cm. In an overall analysis using the ROC curve, without gender and age stratification, the cut-off of 3.67 cm showed good sensitivity, but low specificity. Conclusion Ultrasonography is a useful method to estimate intra-abdominal adipose tissue in adolescents, which is associated with the main factors related to obesity and metabolic syndrome.