SAT-LB020 Use of Ultrasound to Characterize Abdominal Adipose Tissue Distribution and Its Impact on Metabolic Syndrome

Abstract

Body fat distribution play a key role in metabolic syndrome pathogenesis. TC and DEXA imaging allow us to differentiate abdominal subcutaneous from visceral fat. Ultrasound (US) imaging, widely used in thyroid assessment, further allows us to differentiate other abdominal layers: superficial and profound subcutaneous, pre-peritoneal, omental and perirenal (retroperitoneal) fat. Our aim was to measure these layers and correlate them with anthropometric parameters and metabolic syndrome (MS) clinical features. US (GE logic E©) measurement of different abdominal fat layers were done at 397 consecutive patients (28% male 72% female) that came for conventional US for any reason. 12 MHz linear probe for superficial layers and 5 MHz convex probe for intra-abdominal layers assessment have been used. All measures were done at L4 vertebra level to allow comparison with DEXA/CT. Age (16-77 y.o), BMI (22,3-44,7 Kg/m2), abdominal perimeter, % body fat, glucose, HDL, LDL, total cholesterol, triglycerides and HOMA index were recorded. MS criteria were assessed using ATPIII classification. Women showed higher (superficial and profound) subcutaneous fat depots, while men had bigger omental and perirenal fat (p<0,0001). Preperitoneal fat was similar in both genders. Subcutaneous and omental fat depots are increased in the obese subgroup (52% patients) compared to overweight (29%) and normal weight patients (19%) while preperitoneal and perirenal fat did not show any difference according to BMI distribution. Omental fat showed a significant correlation both with BMI (r=0,53; p<0,001) and abdominal perimeter (r=0,55; p<0,001). In NASH patients (41%) there are higher amounts of preperitoneal, omental and perirenal fat. Menopausal women (64%) and diabetic patients (19%) showed significant increases only in omental fat. Patients with MS (74%) showed higher perirenal and omental fat depots. A correlation between US omental fat and HOMA-index was also found (r=0,43 p<0,001). ROC curves show a cut-off point of US omental fat of 54mm (S: 85% E: 65% AUC 0,78 p<0,001) in male and 37mm (S: 73% E: 55% AUC 0,71 p<0,001) in female to predict later development of MS. US measurement is a low-cost and reproducible method useful to assess subcutaneous (profound and superficial) and omental visceral fat. US Omental fat correlates with all anthropometric/biochemical markers associated with obesity and MS. Omental fat measurement may predict the future appearance of MS. Abdominal fat sonography highlight the importance of less-known depots such as preperitoneal and perirenal fat. Unless otherwise noted, all abstracts presented at ENDO are embargoed until the date and time of presentation. For oral presentations, the abstracts are embargoed until the session begins. s presented at a news conference are embargoed until the date and time of the news conference. The Endocrine Society reserves the right to lift the embargo on specific abstracts that are selected for promotion prior to or during ENDO.