Abstract P135: Platelet Activation Is Present In Psoriasis And Associated With Psoriasis Severity And Endothelial Dysfunction

Abstract

Background: Psoriasis is associated with impaired endothelial function and increased CV risk. P-selectin, a platelet transmembrane protein involved in binding leukocytes and endothelial cells, is implicated in CVD. Objective: To explore platelet P-selectin expression in psoriasis and its association with biomarkers of inflammation and endothelial dysfunction. Methods: Patients with psoriasis (n=15, age 51 ± 18 years, 73% male), percent body surface area (BSA) psoriasis 9 ± 20, were compared to controls (Table 1A). The vascular endothelium was assessed via brachial artery flow-mediated dilatation (FMD), a metric of endothelial health and biomarker of CV risk. Platelet P-selectin expression was measured on freshly isolated platelets via flow cytometry in resting and stimulated (thrombin, ADP, arachidonic acid and epinephrine) conditions. High-sensitivity C-reactive protein (hs-CRP) was measured in a clinical laboratory. Results: Psoriasis patients were matched for traditional CV risk factors (Table 1A) aside from diabetes, which trended higher in psoriasis. No difference in hs-CRP was noted, however BSA positively correlated with hs-CRP ( r =0.65, p=0.02), while FMD trended higher in psoriasis vs. controls (5.7% vs. 2.7%, p=0.07) even after accounting for diabetes status (β=-3.0, p=0.08). Platelet analysis revealed higher basal and stimulated P-selectin expression in psoriasis vs. controls (Table 1B). Positive correlations were noted between platelet activation, BSA and hs-CRP, while a negative association was noted between FMD and platelet activation (Table 1C). Conclusion: We describe platelet P-selectin in resting and stimulated conditions as elevated in psoriasis, positively correlated with biomarkers of psoriatic activity, and negatively associated with endothelial health. These findings have important implications for future clinical trials of targeting platelet activity to reduce CV risk in psoriasis.