Arterial Inflammation Detected With ¹⁸ F-Fluorodeoxyglucose-Positron Emission Tomography in Rheumatoid Arthritis

In addition to traditional risk factors, excess cardiovascular disease (CVD) in rheumatoid arthritis (RA) is attributed to enhanced vascular and/or systemic inflammation. In several small studies using ¹⁸ F-fluorodeoxyglucose-positron emission tomography/computed tomography (¹⁸ F-FDG-PET/CT) to directly assess vascular inflammation, FDG uptake was higher in RA patients than in controls. Using a substantially larger sample of RA patients, we sought to identify RA disease characteristics independently associated with vascular FDG uptake.

RA patients underwent cardiac FDG-PET/CT, with aortic inflammation assessed by quantification of FDG uptake in the ascending aorta, calculated as the mean and maximum (max) standardized uptake value (SUV) of the entire ascending aorta and of its most diseased segment (SUV MDS). Univariate and multivariable regression models were constructed to model the associations of patient characteristics with aortic FDG uptake.

Ninety-one RA patients were scanned. In multivariable models, in addition to the independent associations of hypertension and body mass index with increased aortic FDG uptake, the prevalence of rheumatoid nodules correlated with the SUV mean and SUV MDS mean measures, while anti-cyclic citrullinated peptide (anti-CCP) antibodies correlated inversely with these measures and with the SUV max and SUV MDS max (P < 0.05). A significant association of RA disease activity with aortic FDG uptake was observed but was restricted to anti-CCP seropositivity.

Traditional CV risk factors and RA disease characteristics (rheumatoid nodules and the Disease Activity Score in 28 joints using the C-reactive protein level in anti-CCP antibody-positive individuals) were independently associated with ascending aortic FDG uptake in RA patients without clinical CVD.