Threshold value of subepicardial adipose tissue to detect insulin resistance in obese children.

AIM

Until now, the association between subepicardial adipose tissue (SAT), insulin resistance and intima-media thickness (IMT) has not been evaluated in obese children. In this study, we evaluated whether echocardiographic SAT is related to insulin resistance and IMT in obese children.

SUBJECTS AND METHODS

A total of 46 obese subjects (10.2+/-2.5 years of age, 25 male patients) and 30 age- and gender-matched lean subjects (10.8+/-3.1 years of age, 13 male patients) were included in this study. The criterion for diagnosing obesity was defined as the body mass index (BMI) being over 97% percentile of the same gender and age. Serum triglyceride (TG), low- and high-density lipoprotein, cholesterol, glucose and insulin levels were measured during the fasting state. Each subject underwent a transthoracic echocardiogram and the SAT thickness was measured during end-diastole from the parasternal long-axis views.

RESULTS

The obese subjects had significantly higher SAT thickness and IMT values compared with the subjects in the control group (5.7+/-1.4 vs 3.0+/-0.7 mm, 0.78+/-0.15 vs 0.51+/-0.11 mm, P=0.001, respectively). Simple linear regression analysis showed no significant correlation between SAT and insulin resistance (r=0.170, P=0.253), whereas there was significant correlation between SAT and BMI, age and IMT (r=0.625, P=0.02, r=0.589, P=0.001, r=0.343, P=0.02, respectively). As an optimal cutoff point, a SAT thickness of 4.1 mm determined insulin resistance with 90% sensitivity and 61% specificity.

CONCLUSIONS

Our study showed that SAT was significantly correlated with age, BMI and IMT, but not insulin resistance. However, our findings suggest that a 4.1 mm cutoff of SAT thickness might be used as a simple, inexpensive and non-invasive screening method because of its ability to predict insulin resistance with high sensitivity in obese children.