Background:Rheumatoid arthritis (RA) has bene associated with atherosclerosis and cardiovascular (CV) disease. 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18FDG-PET/CT) is suitable to detect synovial and vascular inflammation. Tofacitinib has been used to effectively treat RA.Objectives:We wished to assess the effects of tofacitinib treatment on synovitis and vascular inflammation simultaneously by 18FDG-PET/CT.Methods:Thirty RA patients with active disease were treated with either 5 mg bid or 10 mg bid tofacitinib and evaluated at baseline and after 6 and 12 months. We determined DAS28, CRP, IgM rheumatoid factor (RF) and anti-cyclic citrullinated peptide (aCCP) levels. All patients underwent 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) in order to determine vascular and synovial inflammation in five aortic segments and five articular regions, respectively. In the joints, mean (SUVmean) and maximum standard uptake values (SUVmax), while in the aorta, mean (TBRmean) and maximum target-to-background ratios (TBRmax) were determined. Carotid intima-media thickness (IMT), arterial stiffness (PWV) and endothelial dysfunction (FMD) were determined by ultrasound.Results:One-year tofacitinib treatment significantly attenuated vascular and synovial inflammation as visualized by PET/CT. Articular SUVmean (p=0.010), SUVmax (p=0.001), as well as aorta TBRmax (p<0.001) significantly decreased over time. Synovial inflammation as determined by PET/CT variably and positively associated with aCCP, RF, CRP, ApoB, lipoprotein A (LpA), IMT and PWV. Vascular inflammation (TBRmax) inversely correlated with HAQ and positively with ESR, ApoA, and PWV. Uni- and multivariable analyses suggested that articular SUV values were independently associated with CRP, ApoB, LpA, IMT and PWV, while aortic TBRmax was determined by HAQ and PWV.Conclusion:18F-PET/CT is suitable to simultaneously assess synovial and vascular inflammation in RA. One-year tofacitinib treatment dampened inflammation. PET/CT changes were associated with markers of systemic inflammation, atherogenic lipids, carotid atherosclerosis and arterial stiffness.References:[1]Gotthardt M, Bleeker-Rovers CP, Boerman OC, Oyen WJ. Imaging of inflammation by PET, conventional scintigraphy, and other imaging techniques. J Nucl Med. 2010;51(12):1937-49.[2]Bucerius J, Hyafil F, Verberne HJ, Slart RH, Lindner O, Sciagra R, et al. Position paper of the Cardiovascular Committee of the European Association of Nuclear Medicine (EANM) on PET imaging of atherosclerosis. Eur J Nucl Med Mol Imaging. 2016;43(4):780-92.Acknowledgements:This research was supported by the European Union and the State of Hungary and co-financed by the European Social Fund in the framework of TAMOP-4.2.4.A/2-11/1-2012-0001 ‘National Excellence Program’ (Z.S.); by the European Union grant GINOP-2.3.2-15-2016-00015 (G.P., G.T. and Z.S.) and by the Pfizer Investigator Initiated Research Grant no. WI188341 (Z.S.).Disclosure of Interests:Attila Hamar: None declared, Zsolt Hascsi: None declared, Anita Pusztai: None declared, Monika Czókolyová: None declared, Edit Végh: None declared, Zsófia Pethö: None declared, Katalin Gulyás: None declared, Boglárka Soós: None declared, György Kerekes: None declared, Éva Szekanecz: None declared, Katalin Hodosi: None declared, Sándor Szántó Speakers bureau: Abbvie, MSD, Novartis, Consultant of: Abbvie, MSD, Novartis, Gabriella Szücs Speakers bureau: Boehringer, Actelion, Roche, Consultant of: Boehringer, Actelion, Roche, Tamas Seres: None declared, Zoltán Szekanecz Speakers bureau: Abbvie, Pfizer, Roche, Novartis, Lilly, Sager, Janssen, Consultant of: Pfizer, Abbvie, Roche, Novartis, Grant/research support from: Pfizer, Szilvia Szamosi Speakers bureau: Roche