Impacts of visceral adipose tissue and subcutaneous adipose tissue on metabolic risk factors in middle-aged Japanese.

Regional fat distribution rather than overall fat volume has been considered to be important to understanding the link between obesity and metabolic disorders. We aimed to evaluate the independent associations of visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) with metabolic risk factors in apparently healthy middle-aged Japanese. Participants were 1,119 men and 854 women aged 38-60 years who were not taking medications for diabetes, hypertension, or dyslipidemia. VAT and SAT were measured by use of computed tomography (CT) scanning. VAT and SAT were significantly and positively correlated with each other in men (r = 0.531, P < 0.001) and women (r = 0.589, P < 0.001). In multiple regression analyses, either measure of abdominal adiposity (VAT or SAT) was positively associated with blood pressure, fasting plasma glucose, and log triglyceride (P < 0.001) and inversely with high-density lipoprotein (HDL)-cholesterol (P < 0.001). When VAT and SAT were simultaneously included in the model, the association of VAT with triglycerides was maintained (P < 0.001) but that of SAT was lost. The same was true for HDL-cholesterol in women. For fasting plasma glucose, the association with VAT was strong (P < 0.001) and the borderline association with SAT was maintained (P = 0.060 in men and P = 0.020 in women). Both VAT and SAT were independently associated with blood pressure (P < 0.001). Further adjustment for anthropometric indices resulted in the independent association only with VAT for all risk factors. In conclusion, impacts of VAT and SAT differed among risk factors. VAT showed dominant impacts on triglyceride concentrations in both genders and on HDL-cholesterol in women, while SAT also had an independent association with blood pressure.