Background:
Endothelial dysfunction is an initial step for atherosclerotic cardiovascular disease. However, involvement of vascular inflammation in endothelial dysfunction is not fully investigated in humans. We assessed the relationship between endothelial function and vascular inflammation evaluated by 18F-fluorodeoxyglucose (FDG)-positron emission tomography (PET) imaging.
Methods and Results:
We examined endothelial function and vascular inflammation, which were evaluated by flow-mediated dilation (FMD) of the brachial artery functionally and FDG-PET imaging of carotid arteries, respectively, in 128 subjects (83 males and 45 females; mean age 61.8 ± 10.0 years) who underwent a risk-screening test for cardiovascular disease in Kurume University Hospital. Vascular inflammation of the carotid arteries was measured by blood-normalized standardized uptake value, known as a target-to-background ratio (TBR). Mean percent change in vasodilation (percent change over the baseline values; %FMD) and carotid TBR were 5.60 ± 2.24 % and 1.43 ± 0.22, respectively. %FMD was less in men than in women. In univariate analysis, %FMD was inversely correlated with age (p=0.011), systolic blood pressure (p=0.014), carotid artery maximum intima-media thickness (p=0.014), HbA1c (p=0.020), visceral fat volume (p=0.005), or TBR values (p<0.001). Multiple stepwise regression analysis revealed that age (p=0.034), visceral fat volume (p=0.002), and TBR values (p<0.001) were independently associated with decreased %FMD (R2=0.245).
Conclusions:
We found here that vascular inflammation in the carotid arteries evaluated by FDG-PET was one of the independent association of decreased %FMD, thus suggesting that vascular inflammation might contribute to endothelial dysfunction in humans.