Gender differences in thrombogenicity among patients with angina and non-obstructive coronary artery disease.

Women more often present with angina and non-obstructive coronary artery disease (ANOCA) and have poorer clinical outcomes than men. These findings may be related to sex associated differences in inflammation and thrombogenicity. Consecutive patients (n = 134) with ANOCA (luminal diameter stenosis < 50%) undergoing elective cardiac catheterization were included in post hoc analysis of Multi-Analyte, thrombogenic, and Genetic Markers of Atherosclerosis (MAGMA, NCT01276678) study. Patients with prior revascularization, coronary artery bypass grafting or myocardial infarction were excluded. Blood for thromboelastography, oxidized LDL β2-glycoprotein complex (AtherOx), oxidized-LDL, lipid profile, and urine for 11-dehydrothromboxane B2 (dTxB2) were obtained before catheterization. All women (n = 75) were post-menopausal and tended to be older than men (61.4 ± 10.6 vs. 58.6 ± 9.9 year, p = 0.12), and were significantly more thrombogenic with higher thrombin-induced platelet-fibrin strength (TIP-FCS, mm) (68.0 ± 4.5 vs. 64.5 ± 6.2 mm, p = 0.001), clotting index (0.35 ± 2.22 vs. - 0.72 ± 2.75, p = 0.02), K (measure of the speed to reach 20 mm of clot strength from an amplitude of 2 mm) (2.2 ± 1.6 vs. 1.7 ± 0.5 min, p = 0.01), and fibrinogen activity (degrees) (66.6 ± 7.1 vs. 62.9 ± 7.5, p = 0.009). Markers of inflammation were not significantly different between the two groups. Women had higher total cholesterol, total LDL, LDL subtypes 1 and 2, total HDL, HDL subtypes 2 and 3, and ApoA1 (p < 0.05 for all). On multivariate regression, TIP-FCS remained significantly higher in women (p < 0.0001). Women with ANOCA are more thrombogenic than men. This fundamental difference in thrombogenicity may affect gender-related outcomes and warrants further investigation.