Sex difference in cardiometabolic risk profile and adiponectin expression in subjects with visceral fat obesity

This study investigates the sex difference of cardiometabolic risk profiles in subjects with visceral fat obesity (VFO) but normal waist circumference (WC). VFO, which is defined as visceral adipose tissue (VAT) area more than 100cm2 by computed tomography (CT), and cardiometabolic risk profiles were assessed in 437 subjects with normal WC (197 female subjects and 240 male subjects). The expression of adiponectin and its receptor in abdominal adipose tissue was measured in a subgroup of the subjects. Compared with the male subjects, female subjects had a larger abdominal subcutaneous adipose tissue (SAT) area (158 ± 56 vs 116 ± 38cm2, P < 0.01), smaller VAT area (67 ± 44 vs 78 ± 33cm2; P < 0.01), and lower prevalence of VFO (12.2 vs 24.2%, P < 0.001). This finding was accompanied by upregulated expressions of adiponectin and its receptor in abdominal adipose tissue in female subjects. Without VFO, the risk profiles were not significantly different between male subjects and female subjects. Although risk factors were increased and intensified in both sexes in the presence of VFO, female subjects with VFO were associated with greater cardiometabolic risks than male subjects. A regression analysis indicates the ratio of VAT/SAT for female subjects, whereas VAT and age for male subjects were independently associated with clustering of multiple cardiometabolic risk factors. In conclusion, in subjects with normal WC, the prevalence of VFO is lower and the expression of adiponectin and its receptor is higher in female subjects compared with male subjects. Although VFO was associated with increased risk in both sexes, the risk profile in female subjects with VFO was more pronounced.