Abstract

Geller, B. J., Mega, J. L., Morrow, D. A., Guo, J., Hoffman, E. B., Gibson, C. M., Ruff, C. T. Autoantibodies to phosphorylcholine and cardiovascular outcomes in patients with acute coronary syndromes in the ATLAS ACS-TIMI 46 trial J Thromb Thrombolysis. 2013;NA(NA):NA.

Atherogenesis is a complex inflammatory process stemming from the accumulation and oxidation of low density lipoproteins (LDL). IgM autoantibodies against phosphorylcholine (anti-PC) bind to the PC epitope on oxidized LDL (OxLDL), inhibiting the uptake of oxLDL by macrophages in atherosclerotic lesions. Anti-PC autoantibodies have been reported to be protective against atherothrombosis. We investigated the relationship of anti-PC concentrations with cardiovascular outcomes in patients with acute coronary syndromes (ACS). We measured anti-PC levels within 7 days of an ACS in 3,356 patients enrolled in the ATLAS ACS-TIMI 46 trial, a randomized dose ranging study of rivaroxaban versus placebo. The primary endpoint was death, myocardial infarction (MI), stroke, or severe recurrent ischemia (SRI) requiring revascularization during 6 months. The median baseline anti-PC concentration was 40.9 U/mL (25th, 75th percentiles: 25.4, 67.4). There was no significant association between anti-PC levels and the primary endpoint (Q1: 6.8 %, Q2: 4.2 %, Q3: 7.8 %, Q4: 5.4 %, p-trend = 0.87), all-cause mortality (Q1: 1.4 %, Q2: 0.7 %, Q3: 2.4 %, Q4: 0.9 %, p-trend = 0. 96), or any of the other individual endpoint components (MI: p-trend = 0.87, Stroke: p-trend = 0.43, SRI: p-trend = 0.66). Using the previously reported anti-PC cutpoint of 17 U/mL did not reveal a significant relationship between anti-PC concentrations and cardiovascular outcomes (<17 U/mL: 8.1 % vs. ≥17 U/mL: 5.8 %; p = 0.11). Similarly, evaluation of anti-PC as a continuous variable did not reveal a significant association (p = 0.30). In this study of patients early after ACS undergoing intensive secondary preventive therapy, IgM anti-PC titers did not exhibit a significant relationship with cardiovascular outcomes.

Trial: ATLAS ACS-TIMI 46