PCSK9 and coronary artery disorder: In patients with stable coronary artery disease (CAD), circulating PCSK9 levels exhibit subtype-specific correlations: classical monocytes (CMs) show a positive association (R = 0.29; p = 0.04), while non-classical monocytes (NCMs) are inversely related (R = −0.33; p = 0.02) [165].