Elevated concentrations of oxidized lipoprotein(a) are associated with the presence and severity of acute coronary syndromes.

To investigate possible mechanisms and association of increased oxidized Lp(a) [ox-Lp(a)] levels with presence and extent of acute coronary syndromes (ACS). Ox-Lp(a) levels were studied in 96 patients with ACS, 89 patients with stable coronary artery disease (CAD), and 100 control subjects. Compared to control, ox-Lp(a) levels increased in stable CAD patients (P<0.001), and especially in ACS (P<0.001) (ACS, 16.29+/-13.80 microg/ml; stable CAD, 10.04+/-10.32 microg/ml; control, 7.10+/-9.16 microg/ml). The ratio of ox-Lp(a) to Lp(a) was higher in the ACS than those in the stable CAD (P<0.05) and control (P<0.001). Ox-Lp(a) levels were found associated with a graded increase in extent of angiographically documented CAD in the ACS (R=0.275, P=0.007), while not in the stable CAD (R=0.090, P=0.402). Multiple linear regression analysis found ox-Lp(a) (beta=0.271, P=0.019), age (beta=0.244, P=0.038) and TG (beta=0.213, P=0.070) accounted for 11.1% of the variation in the extent of angiographically documented CAD in ACS patients; Lp(a) (beta=0.415, P=0.000) and extent of CAD (beta=0.193, P=0.071) accounted for 21.5% of that in ox-Lp(a) levels. Elevated ox-Lp(a) levels are associated with presence and severity of ACS, and may be useful for identification of patients with ACS.