Archivos Latinoamericanos de Nutrición (Jun 2010)
Medición ultrasonográfica de grasa visceral intraabdominal en hombres obesos: Asociación con alteración de lípidos séricos e insulinemia Ultrasonography measurement of intrabdominal visceral fat in obese men: Association with alterations in serum lipids and insulinemia
Abstract
La obesidad abdominal, por la adiposidad intraabdominal, conduce a progresión de factores de riesgos cardiometabólicos independientemente del índice de masa corporal. En este trabajo se evaluaron 154 hombres, entre 20 y 60 años de edad, que acudieron a examen anual preventivo de salud laboral en Venezuela. Se utilizó el ultrasonido para establecer la presencia y medición de grasa visceral. La grasa visceral se asoció en forma positiva y significativa con la edad, la circunferencia abdominal y el HOMA-IR tanto en los normopeso como en los de sobrepeso y obeso mientras que con el IMC solo se obtuvo correlación en los normopeso y sobrepeso. En los obesos se observó correlación positiva entre la grasa visceral con la glucemia y los triglicéridos. Con la insulina solo se encontró correlación en los individuos de peso normal. Los valores de grasa visceral se incrementaron con el paso de normopeso-sobrepeso-obeso. Con base a las curvas ROC y tomando como punto de corte para la grasa visceral un valor de 6 cm, se podría predecir hiperglucemia con un 58,6% de sensibilidad y 77% de especificidad; insulino-resistencia con 54% de sensibilidad y 78% de especificidad; hipertrigliceridemia con 39% de sensibilidad y 78% de especificidad y bajo HDLc con 45% de sensibilidad y 77 % de especificidad. El área debajo de la curva en el análisis de ROC fue mayor para la grasa visceral comparado con la circunferencia abdominal para la hiperglucemia (0,727 vs 0,693, pAbdominal obesity and specifically intrabdominal adiposity leads to increase in cardiometabolic risk factors (CMR), independently of body mass index (BMI). In order to examine CMR factors associated with the presence of visceral fat (VF) in individuals with different degrees of overweight/obesity, 154 men, 20 to 60 years of age, attending a at an Industrial Clinic in Venezuela, were evaluated. Ultrasound was used to establish the presence and amount of VF. As expected, VF values were higher as the BMI increased. It was observed that VF was associated positive and significantly with age, abdominal circumference and the degree of insulin resistance (HOMA-IR) in subjects with normal weight as well as in those with overweight and obesity. However, BMI was correlated with VF only in those with normal weight or overweight. In the obese a positive correlation was observed between VF with glycemia and triglycerides, while insulin was correlated with VF only in the subjects with normal weight. Based on the ROC curves, and taking as cut-off point for VF a value of 6 cm, it was possible to predict the presence of hyperglycemia with a 58.6% of sensitivity and 77% of specificity, presence of insulin resistance with 54 % of sensitivity and 78 % specificity, hypertriglyceridemia with 39% of sensitivity and 78% specificity and low HDLc with 45% sensitivity and 77% specificity. The area under the curve for the ROC analysis was greater for visceral fat compared with abdominal circumference for hyperglicemia (0.727 vs. 0.693, p< 0.05) while the opposite was observed for HOMA-IR (0.74 vs. 0.788, p<0.05) and for low HDL-c (0.651 vs. 0.668, p<0.05). We conclude that ultrasound measure of VF, was better in predicting hyperglycemia and hypertriglyceridemia, while abdominal circumference was better predicting insulin resistance and low HDLc and could be useful in the preventive evaluation of individuals at risk for diabetes or cardiovascular disease.
