Gender differences in the association of visceral and subcutaneous adiposity with adiponectin in African Americans: the Jackson Heart Study

Abstract

Background: Adiponectin, paradoxically reduced in obesity and with lower levels in African Americans (AA), modulates several cardiometabolic risk factors. Because abdominal visceral adipose tissue (VAT), known to be reduced in AA, and subcutaneous adipose tissue (SAT) compartments may confer differential metabolic risk profiles, we investigated the associations of VAT and SAT with serum adiponectin, separately by gender, with the hypothesis that VAT is more strongly inversely associated with adiponectin than SAT.

Methods: Participants from the Jackson Heart Study, an ongoing cohort of AA (n = 2,799; 64% women; mean age, 55 ± 11 years) underwent computer tomography assessment of SAT and VAT volumes, and had stored serum specimens analyzed for adiponectin levels. These levels were examined by gender in relation to increments of VAT and SAT.

Results: Compared to women, men had significantly lower mean levels of adiponectin (3.9 ± 3.0 μg/mL vs. 6.0 ± 4.4 μg/mL; p < 0.01) and mean volume of SAT (1,721 ± 803 cm(3) vs. 2,668 ± 968 cm(3); p < 0.01) but significantly higher mean volume of VAT (884 ± 416 cm(3) vs. 801 ± 363 cm(3); p < 0.01). Among women, a one standard deviation increment in VAT was inversely associated with adiponectin (β = - 0.13; p < 0.0001) after controlling for age, systolic blood pressure, fasting plasma glucose, high-density lipoprotein cholesterol, triglycerides, education, pack-years of smoking and daily intake of alcohol. The statistically significant inverse association of VAT and adiponectin persisted after additionally adjusting for SAT, body mass index (BMI) and waist circumference (WC), suggesting that VAT provides significant information above and beyond BMI and WC. Among men, after the same multivariable adjustment, there was a direct association of SAT and adiponectin (β = 0.18; p = 0.002) that persisted when controlling for BMI and WC, supporting a beneficial effect of SAT. Insulin resistance mediated the association of SAT with adiponectin in women.

Conclusion: In African Americans, abdominal visceral adipose tissue had an inverse association with serum adiponectin concentrations only among women. Abdominal subcutaneous adipose tissue appeared as a protective fat depot in men.

Figure 1

Mean adiponectin levels in JHS women participants partitioned by tertiles of VAT and tertiles of SAT. Subgroup sizes for each SAT tertile within VAT tertile were 200, 201 and 200 from the lowest to the highest. Error bars represent standard errors. P-values are given for linear trend in means of adiponectin levels.

Figure 2

Mean adiponectin levels in JHS men participants partitioned by tertiles of VAT and tertiles of SAT. Subgroup sizes for each SAT tertile within VAT tertile were 111, 111 and 110 from the lowest to the highest. Error bars represent standard errors. P-values are given for linear trend in means of adiponectin levels.