Abstract P293: Relations of Abdominal Subcutaneous and Visceral Fat Quality with a Panel of Metabolic Regulatory Biomarkers
Introduction: Excess accumulation of abdominal subcutaneous (SAT) and visceral adipose tissue (VAT) is associated with metabolic regulatory biomarkers and an increased risk for developing type 2 diabetes, dyslipidemia and cardiovascular disease. Abdominal fat quality is related to cardiovascular disease risk factors above and beyond fat quantity. However, whether fat quality is associated with biomarkers of metabolic regulation has not been firmly established.
Hypothesis: We hypothesized that SAT and VAT attenuation, an indirect measure of fat quality, would be associated with a panel of metabolic regulatory biomarkers secreted by adipose tissue or liver, independently of absolute fat volumes.
Methods: We evaluated 1,829 Framingham Heart Study participants (44.9% women, mean age 45.0 years) with available data on abdominal fat attenuation and metabolic biomarkers. SAT and VAT fat attenuation was determined by multidetector computed tomography (CT) and denoted in Hounsfield units (HU). Panels of circulating biomarkers included adiponectin, leptin, leptin receptor, fatty acid binding protein-4 (FABP-4), retinol binding protein-4 (RBP-4) and fetuin-A. The relationships between SAT or VAT HU and each of the biomarkers were modeled using sex-specific linear regression model, adjusting for age, hormone replacement therapy (women), smoking status, alcohol use, and physical activity score. Biomarkers were log-transformed to normalize their distribution.
Results: In both sexes, SAT and VAT attenuation were associated with all the biomarkers evaluated, except fetuin-A. Lower (i.e., more negative) attenuation of SAT and VAT was associated with lower circulating adiponectin and leptin receptor levels but higher leptin and FABP-4 levels in both women and men (all p <0.0001). SAT attenuation was inversely associated with RPB-4 levels in both sexes; whereas, the association between VAT attenuation and RPB-4 was only observed in men (p <0.0001). In women, after additional adjustment for the respective fat volume, SAT HU retained the statistically significant associations with adiponectin, leptin, FABP, and RBP-4; and VAT HU with adiponectin only (all p <0.0001). In men, associations remained significant after additional adjustment for the respective fat volume (all p <0.005).
Conclusions: Lower attenuation of abdominal fat was associated with a profile of biomarkers suggestive of greater cardiometabolic risks. These observations suggest that fat attenuation may be a valid biomarker of cardiometabolic risk. Further study is required to identify whether the quality of abdominal fat has a pathogenic impact on metabolism via its relationship with biomarkers secreted by adipose tissue or the liver.
Author Disclosures: J.J. Lee: None. A. Pedley: None. U. Hoffmann: None. J.F. Keaney: None. R.S. Vasan: None. C.S. Fox: None.
- © 2015 by American Heart Association, Inc.