Abstract 16232: Lipoprotein(a) is Not Associated With the Risk of Ischemic Cardiovascular Events Following Acute Coronary Syndrome

• Published in: Circulation (New York, N.Y.) N.Y.), 2016-11, Vol.134 (Suppl_1 Suppl 1), p.A16232-A16232
• Main Authors: Schwartz, Gregory G, Ballantyne, Christie M, Barter, Philip J, Kallend, David, Leitersdorf, Eran, Leiter, Lawrence A, McMurray, John J, Nicholls, Stephen J, Olsson, Anders G, Pitts, Reynaria, Shah, Prediman K, Tardif, Jean-Claude, Kittelson, John
• Format: Article
• Language: English
• ISSN: 0009-7322; 1524-4539

BackgroundLipoprotein(a) [Lp(a)] is associated with incident cardiovascular (CV) risk in observational cohorts, but it is unclear whether Lp(a) is an independent risk factor for recurrent CV events after acute coronary syndrome (ACS) in patients treated with statins. Also, because Lp(a) is an acute phase reactant, its predictive value after ACS may be more reliably assessed after a period of clinical stabilization.ObjectiveWe examined the association of Lp(a) with major adverse CV events in patients with recent ACS.MethodsA nested case-control analysis was performed in the dal-OUTCOMES trial that compared the CETP inhibitor, dalcetrapib, with placebo in 15872 patients. Patients were randomized 4-12 weeks after ACS when they were clinically stable and followed for a mean of 31 months. Cases were 972 patients who experienced CV death, non-fatal MI, stroke, hospitalization for unstable angina, or resuscitated cardiac arrest; 974 controls were matched for type of index ACS event (MI or unstable angina) and follow-up time. Lp(a) was measured on cases and controls by immunoturbidimetric assay with operating range 7-240 nmol/L (3-100 mg/dL).ResultsAt baseline, median Lp(a) was 30 (11-125) nmol/L. Statins were used in 97% of patients; mean LDL-C was 78 mg/dL. The distribution of Lp(a) levels did not differ between cases and controls (Figure). Conditional logistic regression showed no association of baseline Lp(a) with risk of CV events. For a doubling of Lp(a), the odds ratio (case:control) was 1.025 (95% CI 0.976-1.077, p=0.32) unadjusted and 1.043 (95% CI 0.987-1.103, p=0.14) after adjustment for age, sex, race, HTN, diabetes, BMI, smoking, HbA1c, LDL-C, HDL-C, triglycerides, and assigned treatment.ConclusionIn patients with ACS who are treated with statins and beyond the period of acute phase response, Lp(a) levels do not associate with adverse CV outcomes. The findings call into question whether treatment directed at reducing Lp(a) will reduce risk after ACS.