Arterial wall inflammation, as measured by 18-fluorodeoxyglucose positron emission tomography (PET) combined with computed tomography (CT; 18F-FDG-PET/CT), is increased in patients with rheumatoid arthritis (RA) compared with patients with osteoarthritis (OA), according to study results published in Rheumatology.
Previous studies have suggested that the inflammatory process associated with RA may involve the arterial wall, leading to an increased risk for cardiovascular disease. The use of FDG-PET/CT can help in identifying plaque inflammation; higher 18F-FDG uptake can serve as a marker of early atherosclerosis.
The objective of the current study was to determine the arterial wall inflammation in patients with RA compared with patients with OA, and to investigate its association with inflammatory markers and cardiovascular risk factors.
The study included 61 patients with RA (mean age, 63 years; 55.7% women) and 28 patients (mean age, 63 years; 57.1% women) with OA.
Patients with RA vs those with OA had a significantly increased 18F-FDG uptake in the aorta, femoral, and carotid arteries, even after controlling for age, sex, and other traditional cardiovascular risk factors.
In a secondary analysis, 18F-FDG uptake was determined in 3 groups: patients with newly diagnosed and untreated RA (n=30); patients with active RA receiving conventional disease-modifying antirheumatic drug treatment (n=31); and patients with OA.
Patients with early RA had the highest 18F-FDG uptake, followed by patients with established RA, and patients with OA. After adjustment for erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) levels, the differences were reduced or not significant, suggesting that differences in systemic inflammation are at least partially responsible for the differences in arterial wall inflammation between groups.
Among patients with RA, higher ESR was associated with increased 18F-FDG uptake in the arterial wall of carotid, aorta, iliac, and femoral arteries. Higher CRP and RA disease activity were significantly associated with a higher 18F-FDG uptake in all arterial segments.
The study had several limitations, including relatively small sample size and lack of a healthy control group with enough statistical power to compare the results among patients with RA and healthy control participants.
“[F]urther studies are needed to investigate the direct effects of anti-inflammatory therapy on the vascular wall as measured by methods such as an 18F-FDG-PET/CT,” the researchers wrote.
Disclosure: This study was partly supported by Abbvie.
Agca R, Blanken AB, van Sijl AM, et al. Arterial wall inflammation is increased in rheumatoid arthritis compared with osteoarthritis, as a marker of early atherosclerosis Rheumatology (Oxford). Published online January 14, 2021. doi:10.1093/rheumatology/keaa789