Clinical Significance of Abdominal Deep Subcutaneous Adipose Tissue in the Obese: Associations with Cardiovascular and Risk Factors

ABSTRACT

BACKGROUND: It is well known that the metabolic syndrome is associated with visceral adipose tissue (VAT), but several recent studies showed stronger association between the subcutaneous adipose tissue (SAT) and insulin resistance. The purpose of this study was to investigate the clinical significance of deep SAT as a cardiovascular and a metabolic risk factor. METHODS: A cross-sectional survey was conducted among fifty-one subjects (21 men and 30 women) who visited an obesity clinic in Yeungnam University Hospital. We performed cross-sectional abdominal CT, and undertook the novel approach of partitioning SAT into the plane superficial to the fascia within SAT (Superficial SAT) and within subcutaneous adipose tissue (deep SAT), as well as the measurement of VAT. Percent body fat was measured by bioimpedance analysis (Inbody 2.0, Biospace). Fasting blood samples were analyzed for total cholesterol, HDL-cholesterol, TG, LDL-cholesterol, FFA, insulin, uric acid and glucose. Resting blood pressure was measured. RESULTS: After adjustment for age, sex, smoking, alchol and exercise, deep SAT was proved to be significantly and positively correlated with fasting insulin, FFA, and uric acid (P<0.05). VAT was significantly correlated with unfavorable levels of FFA, insulin, HDL-cholesterol, TG and diastolic blood pressure (P<0.05). In stepwise multiple regression analysis, deep SAT was shown to be the most powerful of the adiposity measures for explaining the variance in fasting insulin and uric acid levels (r2=0.196 and 0.225, respectively; both P<0.001; including superficial SAT, deep SAT, VAT). CONCLUSION: Our results suggest that the association exists between deep SAT and fasting insulin, a finding which provides further support to the observation that deep SAT may be involved in insulin sensitivity.