Abstract 14874: Circulating Oxidized Lipoprotein (a) as a New Risk Factor and Independent Predictor for Adverse Outcomes in Coronary Artery Disease Patients
Background: We have recently shown that oxidized lipoprotein (a) [Lp(a)] increases in patients with coronary artery disease (CAD) and that it might be independently associated with the severity of CAD. Therefore, we prospectively investigated the prognostic value of oxidized Lp(a) in patients with suspected CAD.
Methods: We measured serum oxidized Lp(a) using a new ELISA method in 510 patients (median age, 64 yrs; 395 males) who underwent elective coronary angiography for evaluating CAD. Among these patients, 60% had significant stenosis (>75%) of the coronary artery, 32% had multi-vessel disease, 42% had old myocardial infarction, 52% had hypertension, 29% had diabetes, and 49% had hyperlipidemia.
Results: During a median follow-up period of 52 months, 94 cardiovascular events were reported. These events were defined as cardiovascular death or readmission for acute coronary syndrome, heart failure, or stroke. Comparably, patients with a cardiovascular event were older (median, 67 vs. 64 yrs, P = 0.007), had higher levels of oxidized Lp(a) (0.180 vs. 0.066 nmol/L, P < 0.0001), Lp(a) (10.6 vs. 7.65 nmol/L, P = 0.001) and high-sensitive CRP (1.1 vs. 0.70 mg/L, P = 0.001). In addition, these patients presented with higher prevalence of diabetes (42 vs. 27%, P = 0.003) and multi-vessel disease (56 vs. 41%, P = 0.009), and displayed a lower level of estimated GFR (73 vs. 84 mL/min/1.73 m2, P < 0.0001) than those without a cardiovascular event. On stepwise Cox regression analysis including 13 clinical and biochemical variables, oxidized Lp(a) (relative risk 1.39 per 10-fold increment, P = 0.002), but not Lp(a), was independently associated with cardiovascular events. Cardiovascular mortality and morbidity rates according to oxidized Lp(a) quartiles were shown in table.
Conclusions: We have demonstrated that oxidized Lp(a) may be an independent predictor for adverse outcomes in patients with suspected CAD. These data also indicate that oxidized Lp(a) is a new risk factor for CAD.
- © 2010 by American Heart Association, Inc.