Intra-abdominal fat measurement by ultrasonography: association with anthropometry and metabolic syndrome in adolescents / Gordura intra-abdominal medida por ultrassonografia: relação com antropometria e síndrome metabólica em adolescentes

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 < 0.001), elevated triglyceride levels (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.

Resumo Objetivo: Relacionar a espessura da gordura intra-abdominal medida pela ultrassonografia aos fatores ligados à síndrome metabólica. Determinar pontos de corte da medida da gordura intra-abdominal associados a uma maior chance de síndrome metabólica em adolescentes. Métodos: Estudo seccional, com 423 adolescentes de escolas públicas. A gordura intra-abdominal foi medida pela ultrassonografia. Foram coletados dados antropométricos e feitas análises bioquímicas. Resultados: As medidas da gordura intra-abdominal por ultrassonografia apresentaram associação estatisticamente significativa com o diagnóstico de síndrome metabólica (p = 0,037), índice de massa corporal (p < 0,001), níveis elevados de triglicerídeos (p = 0,012), redução dos níveis plasmáticos de HDL (p = 0,034) e aumento da pressão arterial sistêmica (p = 0,023). Calcularam-se pontos de corte da medida da espessura da gordura intra-abdominal por ultrassom, para estimar os indivíduos com mais chance para o desenvolvimento de síndrome metabólica. Em modelos de regressão logística, os pontos de corte que apresentaram maior associação com a síndrome metabólica no sexo masculino foram de 4,50, 5,35, 5,46, 6,24 e 6,50 cm para as idades de 14, 15, 16, 17 e 18/19 anos, respectivamente. No sexo feminino, os pontos de corte definidos para as mesmas faixas etárias foram de 4,46, 4,55, 4,45, 4,90 e 6,46 cm. Em análise global por meio da curva ROC, sem estratificações por sexo e idade, o ponto de corte de 3,67 cm teve boa sensibilidade, porém apresentou baixa especificidade. Conclusão: A ultrassonografia é um método útil para a estimativa do tecido adiposo intra-abdominal em adolescentes, está associada com os principais fatores relacionados à obesidade e à síndrome metabólica.

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

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<0.001), elevated triglyceride levels (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 6.50cm 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 6.46cm. In an overall analysis using the ROC curve, without gender and age stratification, the cut-off of 3.67cm 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.