Glucose metabolism of visceral adipose tissue evaluated by 18F-FDG PET/CT reflects inflammatory status in metabolic syndrome

초록

Background and Aims: The risk of cardiovascular disease is elevated in metabolic syndrome (MS) and is related to the inflammatory activity of visceral adipose tissue (VAT). This inflammation is related to dysfunctional adipocytes, mostly composed of VAT, in addition to scattered immune cells. In this prospective 18F-FDG PET/CT study of VAT, we investigated whether the SUVmax of VAT, is correlated with the index of systemic inflammation and whether SUVmax changes according to the number of MS components Methods: We investigated glucose uptake of VAT using 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) in 203 participants: 59 without MS component; M(0), 92 with one or two MS components; M(1-2), and 52 with MS. Glucose uptake in VAT was evaluated using the mean standardized uptake value (SUVmean) and the maximum SUV (SUVmax). Glucose uptakes of immune-related organs such as the spleen and bone marrow (BM) were evaluated using the SUVmax. Results: VAT SUVmax correlated with high-sensitivity C-reactive protein (hsCRP) and the SUVmax of spleen and BM, which reflect the status of systemic inflammation. Both hsCRP and the SUVmax of the spleen and BM were higher in the MS group than in the M(1-2) or M(0) groups. In VAT, SUVmax increased with increasing number of MS components, while SUVmean decreased. Conclusions: The SUVmax and SUVmean of VAT assessed by 18F-FDG PET/CT reflected inflammation-driven unique glucose metabolism in the VAT of MS patients, distinct from that of atherosclerotic plaques.