Vascular Inflammation Evaluated by [18F]-Fluorodeoxyglucose-Positron Emission Tomography/Computed Tomography Is Associated With Endothelial Dysfunction.

Abstract

Endothelial dysfunction is an initial step in atherosclerotic cardiovascular disease. However, involvement of vascular inflammation in endothelial dysfunction is not fully investigated in humans because of the lack of diagnostic modality to noninvasively evaluate vascular inflammation. We assessed the relationship between endothelial function and vascular inflammation evaluated by [(18)F]-fluorodeoxyglucose-positron emission tomography/computed tomographic imaging. We examined endothelial function and vascular inflammation by flow-mediated dilation (FMD) of the brachial artery and [(18)F]-fluorodeoxyglucose-positron emission tomography/computed tomographic imaging of carotid arteries, respectively, in 145 subjects (95 men and 50 women; mean age, 61.8±9.5 years) who underwent a risk-screening test for cardiovascular disease in Kurume University Hospital. Vascular inflammation was measured by blood-normalized standardized uptake value, known as a target:background ratio (TBR). We investigated whether absolute changes from baseline of %FMD after antihypertensive treatment for 6 months (Δ%FMD) were correlated with those of TBR in 33 drug-naive patients with essential hypertension. Multiple logistic regression analysis revealed that age (odds ratio, 1.767 for 10-year increase), male sex (odds ratio, 0.434), low-density lipoprotein-cholesterol (odds ratio, 1.630 for 26-mg/dL increase), and TBR values (odds ratio, 1.759 for 0.2 increase) were independently associated with %FMD in 145 patients. There was an inverse correlation between Δ%FMD and ΔTBR; ΔTBR was a sole independent associate of Δ%FMD in hypertensive patients (r=-0.558; P<0.001). The present study showed that vascular inflammation in the carotid arteries evaluated by [(18)F]-fluorodeoxyglucose-positron emission tomography/computed tomography was one of the independent correlates of decreased %FMD, thus suggesting the association of vascular inflammation with endothelial dysfunction in humans.