Pericardial fat volume correlates with inflammatory markers: the Framingham Heart Study

The objective of this study was to determine whether systemic inflammatory and oxidative stress marker concentrations correlate with pericardial and intrathoracic fat volumes. Participants of the Framingham Offspring Study (n = 1,175, 53% women, mean age 59 +/- 9 years) had pericardial and intrathoracic fat volumes assessed by multidetector computed tomography (MDCT) scans, and provided fasting blood and urine samples to measure concentrations of 14 inflammatory markers: C-reactive protein (CRP), interleukin-6, monocyte chemoattractant protein-1 (MCP-1), CD40 ligand, fibrinogen, intracellular adhesion molecule-1, lipoprotein-associated phospholipase A(2) activity and mass, myeloperoxidase, osteoprotegerin, P-selectin, tumor necrosis factor-alpha, tumor necrosis factor receptor-2, and urinary isoprostanes. Multivariable linear regression models were used to determine the association of log-transformed inflammatory marker concentrations with fat volumes, using fat volume as the dependent variable. Due to smaller sample sizes, models were rerun after adding urinary isoprostanes (n = 961) and tumor necrosis factor-alpha (n = 813) to the marker panel. Upon backward elimination, four of the biomarkers correlated positively with each fat depot: CRP (P < 0.0001 for each fat depot), interleukin-6 (P < 0.05 for each fat depot), MCP-1 (P < 0.01 for each fat depot), and urinary isoprostanes (P < 0.01 for pericardial fat; P < 0.001 for intrathoracic fat). Even after adjusting for BMI, waist circumference (WC), and abdominal visceral fat, CRP (P = 0.0001) and urinary isoprostanes (P = 0.02) demonstrated significant positive associations with intrathoracic fat, but not with pericardial fat. Multiple markers of inflammation and oxidative stress correlated with pericardial and intrathoracic fat volumes, extending the known association between regional adiposity and inflammation and oxidative stress.