GlycA, an emerging inflammatory biomarker, predicted cardiovascular events in population-based studies. Psoriasis, an inflammatory disease associated with increased cardiovascular risk, provides a model to study inflammatory biomarkers in cardiovascular disease (CVD). Whether GlycA associates with psoriasis and how it predicts subclinical CVD beyond high-sensitivity C-reactive protein in psoriasis is unknown.To investigate the relationships between GlycA and psoriasis and between GlycA and subclinical CVD.Patients with psoriasis and controls (n=412) participated in a 2-stage study. We measured GlycA by nuclear magnetic resonance spectroscopy. National Institutes of Health (NIH) participants underwent 18-F Fluorodeoxyglucose Positron Emission Tomography Computed Tomography (18-FDG PET/CT) scans to assess vascular inflammation (VI) and coronary computed tomographic angiography to quantify coronary artery disease burden. Psoriasis cohorts were young (mean age=47.9), with low cardiovascular risk and moderate skin disease. high-sensitivity C-reactive protein and GlycA were increased in psoriasis compared with controls (GlycA: [PENN: 408.8±75.4 versus 289.4±60.2, P<0.0001; NIH: 415.8±63.2 versus 346.2±46, P<0.0001]) and demonstrated a dose-response with psoriasis severity. In stage 2, VI (β=0.36, P<0.001) and coronary artery disease (β=0.29, P=0.004) associated with GlycA beyond CV risk factors in psoriasis. In receiver operating characteristic analysis, GlycA added value in predicting VI (P=0.01) and coronary artery disease (P<0.01). Finally, initiating anti-tumor necrosis factor therapy (n=16) reduced psoriasis severity (P<0.001), GlycA (463.7±92.5 versus 370.1±78.5, P<0.001) and VI (1.93±0.36 versus 1.76±0.19, P<0.001), whereas GlycA remained associated with VI (β=0.56, P<0.001) post treatment.GlycA associated with psoriasis severity and subclinical CVD beyond traditional CV risk and high-sensitivity C-reactive protein. Moreover, psoriasis treatment reduced GlycA and VI. These findings support the potential use of GlycA in subclinical CVD risk assessment in psoriasis and potentially other inflammatory diseases.