RELATIONSHIP OF ANTERIOR AND POSTERIOR SUBCUTANEOUS ABDOMINAL FAT TO INSULIN SENSITIVITY IN NONDIABETIC MEN

Recent studies from our group reveal that adipose tissue (AT) in the s ubcutaneous abdominal region is the most important determinant of peri pheral and hepatic insulin sensitivity. Because of different anatomic and physiologic characteristics of anterior and posterior subcutaneous abdominal AT, we investigated the relationship of the masses of each compartment, as determined by magnetic resonance imaging, to insulin s ensitivity (using euglycemic hyperinsulinemic glucose clamp technique) , and other anthropometric variables. Thirty-four healthy men with var ying ranges of obesity were recruited for the study. The mass of poste rior subcutaneous abdominal AT was similar to 1.6 times more than that of the anterior compartment, and these masses accounted for 12.9% and 8.2% of the total body fat mass, respectively. All anthropometric var iables, including body mass index (BMI), waist-to-hip circumference ra tio (WHR), skin-fold thicknesses, and intraperitoneal AT mass were mor e significantly related to the posterior than the anterior subcutaneou s abdominal AT mass. Compared to the anterior compartment mass, the po sterior compartment mass displayed stronger relationship with insulin- mediated glucose disposal (Rd) (r=-0.44, p=0.009, and r=-0.76, p=0.000 1, respectively) as well as with residual hepatic glucose output durin g the 40 mU . m-2 . min(-1) insulin infusion (r-0.39, p=0.02, and r=0. 53, p=0.001, respectively). After adjusting for total body fat, the Rd values showed a significant partial correlation with the posterior su bcutaneous abdominal AT mass (r=-0.52, p=0.002). To conclude, posterio r subcutaneous abdominal AT mass is a more important determinant of pe ripheral and hepatic insulin sensitivity than the anterior subcutaneou s abdominal AT.