Do statins decrease vascular inflammation in patients at risk for large-vessel vasculitis? A retrospective observational study with FDG-PET/CT in polymyalgia rheumatica, giant cell arteritis and fever of unknown origin.

[18F] Fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) can detect the presence of large-vessel vasculitis (LVV) in patients with polymyalgia rheumatica (PMR), giant cell arteritis (GCA) and fever of unknown origin (FUO). The aim of this study was to evaluate whether statins could reduce FDG-PET/CT-assessed vascular inflammation in this group of patients. Clinical, demographic, laboratory data, current pharmacological treatments, and cardiovascular risk factors of patients with PMR, GCA and FUO, who underwent FDG-PET/CT, were recorded. FDG uptake was measured at prespecified arterial sites with the mean standardised uptake value (SUV), and with a qualitative visual score, summed up to obtain a total vascular score (TVS). LVV was diagnosed if arterial FDG visual uptake was equal or higher of liver uptake. 129 patients were included (96 with PMR, 16 with GCA, 13 with both PMR and GCA, and 4 with FUO), of whom 75 (58.1%) showed LVV. Twenty out of 129 (15.5%) patients were taking statins. TVS was significantly lower in patients treated with statins (p=0.02), especially in the aorta (p=0.023) and femoral arteries (p=0.027). Our preliminary results suggest that statins may exert a potential protective role on vascular inflammation in patients with PMR and GCA. Statin use could spuriously decrease FDG uptake of the vessel walls.