Abstract 15758: Platelet Aggregation is Elevated in Psoriasis and Associated With Cardiovascular Risk

Abstract

Introduction: Psoriasis is associated with increased CV risk the mechanisms and prevention of which are not fully known. We evaluated the platelet phenotype (implicated in atherothrombosis) and in vitro response to aspirin in patients with psoriasis and its association with vascular stiffness and coronary atherosclerosis. Methods: Patients with psoriasis (n = 64, age 47.9 ± 15 years, 65% male), percent body surface area (BSA) of psoriasis 3%, were compared to controls (n = 40, age 40.8 ± 16 years, 45% male). Percent platelet aggregation in response to agonists adenosine diphosphate (ADP), collagen (Col), and arachidonic acid (AA - with and without aspirin) was measured in freshly isolated platelet-rich plasma via light transmission aggregometry (LTA). Vascular stiffness (via pulse wave velocity [PWV]) and CT coronary angiography were each performed as readouts of CV risk. Results: Compared to controls, psoriasis patients were older, of Caucasian ethnicity (Figure 1A), and overweight, but otherwise similar. Platelet aggregation after treatment with Col (p=0.01), ADP (p < 0.01), and AA (p = 0.05) were all higher in psoriasis vs. control (Figure 1B-D). Platelet aggregation after activation with high dose AA was similar between groups (Figure 1E) however co-incubation with high dose AA plus aspirin displayed incomplete platelet inhibition of psoriasis platelets vs. controls (Figure 1F). Platelet aggregation to low dose AA and high dose AA plus aspirin co-incubation were each higher in those with enhanced vascular stiffness (figure 1G/1H) and the presence of coronary plaque (Figure 1I/1J). Conclusion: Platelet aggregation is consistently elevated in psoriasis across a variety of agonists, incompletely inhibited by aspirin, and associated with biomarkers of CV risk such as vascular stiffness and the presence of coronary plaque. These findings highlight the need to evaluate various anti-platelet strategies to reduce atherothrombotic risk in patients with psoriasis.