Increased global arterial and subcutaneous adipose tissue inflammation in patients with moderate-to-severe psoriasis

Background Psoriasis is associated with cardiovascular disease and it has been proposed that the increased cardiovascular risk is caused by low-grade systemic inflammation involving organs and tissues other than the skin and joints, e.g., subcutaneous adipose tissue. Objective To investigate signs of vascular inflammation in untreated patients with moderate-to-severe psoriasis compared with retrospectively matched control subjects assessed from 18F−fluorodeoxyglucose (FDG) positron emission tomography (PET) computed tomography (CT). A secondary objective was to assess signs of subcutaneous adipose tissue inflammation. Methods This was an observational, controlled clinical study including patients with moderate-to-severe psoriasis (n=12, mean [SD] age 61.4 [4.1] years, 83% men with a mean Psoriasis Area Severity Index (PASI) score of 14.5 [4.3], and matched controls (n=23, age 60.4 [4.5] years, 87% men). Vascular inflammation was measured using aortic maximal standardized uptake values (SUVmax) and the target-to-background ratio (TBRmax) of the whole vessel and aortic segments. Subcutaneous adipose tissue inflammation was assessed and compared as SUVmax and TBRmax. Results Arterial inflammation was increased in psoriasis patients compared with controls (mean whole vessel TBRmax 2.46 [0.31] versus 2.09 [0.36]; P=0.005). Average normalized FDG uptake based on conservative 10-pixel cut-off SUVmax values was also increased in psoriasis patients (mean TBRmax-10pixels 2.13 [0.21] versus 1.92 [0.30]; P=0.03). In psoriasis patients, higher FDG uptake values were observed for all aortic segments except the ascending aorta. Subcutaneous adipose tissue FDG uptake was increased in psoriasis patients compared with controls (mean TBRmax 0.49 [0.18] versus 0.31 [0.12]; P=0.002; and mean TBRmax-10pixels 0.39 [0.10] versus 0.28 [0.12]; P=0.01). Conclusion Both global arterial inflammation and subcutaneous inflammation were significantly increased in patients with moderate-to-severe psoriasis compared with controls. This article is protected by copyright. All rights reserved.