ORIGINAL ARTICLE Threshold value of subepicardial adipose tissue to detect insulin resistance in obese children A Abacı 1 , ME Tascılar 1 , T Sarıtas 2 , Y Yozgat 2 , E Yesilkaya 1 , A Kılıc 2 , V Okutan 2 and MK Lenk 2 1 Department of Pediatric Endocrinology, Gulhane Military Medical Academy, Ankara, Turkey and 2 Department of Pediatric Cardiology, Gulhane Military Medical Academy, Ankara, Turkey 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 ¼ 0.001, respectively). Simple linear regression analysis showed no significant correlation between SAT and insulin resistance (r ¼ 0.170, P ¼ 0.253), whereas there was significant correlation between SAT and BMI, age and IMT (r ¼ 0.625, P ¼ 0.02, r ¼ 0.589, P ¼ 0.001, r ¼ 0.343, P ¼ 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. International Journal of Obesity (2009) 33, 440–446; doi:10.1038/ijo.2009.1; published online 17 February 2009 Keywords: children; subepicardial adipose tissue; intima–media thickness; insulin resistance Introduction Visceral adiposity seems to play a key role in the develop- ment of obesity-related complications. 1 However, it is difficult to obtain an accurate measurement and characteri- zation of visceral adipose tissue. 2,3 Until now, several simple (waist circumference) and non-simple (magnetic resonance imaging, computed tomography) methods have been applied for estimation of body composition and visceral adipose tissue accumulation. 4 Recently, echocardiographic subepicardial adipose tissue (SAT) measurement has been proposed and validated as a new method to estimate visceral adipose tissue. 1,4 It was reported that SAT thickness was significantly correlated with the severity of coronary artery disease and could be easily obtained as an indicator in patients with high cardiovascular risk. 1,4,5 In addition, recent reports have shown that SAT expresses numerous genes for cytokines and proteins associated with atherosclerosis. 6,7 Furthermore, SAT thickness was shown to be related to fasting glucose, insulin resistance and inflammation. 8,9 Therefore, we think that echocardiographic SAT thickness evaluation might be important for risk stratification of obesity-related complications in obese children as well as obese adult patients. An association between echocardiographic SAT thickness and anthropometric and laboratory values has been reported in obese adult patient studies, but it has not yet been explored in obese children. For this reason, this study was designed to assess the association between SAT, anthropo- metric (body mass index (BMI), carotid intima–media thickness (IMT), systolic and diastolic blood pressures) and Received 9 July 2008; revised 20 December 2008; accepted 22 December 2008; published online 17 February 2009 Correspondence: Dr A Abacı, Department of Pediatric Endocrinology, Gulhane Military Medical Academy, Ankara 6001, Turkey. E-mail: ayhanabaci@gmail.com International Journal of Obesity (2009) 33, 440–446 & 2009 Macmillan Publishers Limited All rights reserved 0307-0565/09 $32.00 www.nature.com/ijo