Residual thromboxane activity and oxidative stress: influence on mortality in patients with stable coronary artery disease.
Peter McCullough M.D.
Vasudevan, A., T. Bottiglieri, K. M. Tecson, M. Sathyamoorthy, J. M. Schussler, C. E. Velasco, L. R. Lopez, C. Swift, M. Peterson, J. Bennett-Firmin, R. Schiffmann and P. A. McCullough (2017). “Residual thromboxane activity and oxidative stress: Influence on mortality in patients with stable coronary artery disease.” Coron Artery Dis 28(4): 287-293.
BACKGROUND: Aspirin use is effective in the prevention of cardiovascular disease; however, not all patients are equally responsive to aspirin. Oxidative stress reflected by F2-isoprostane [8-iso-prostaglandin-F2alpha (8-IsoPGF2alpha)] is a potential mechanism of failure of aspirin to adequately inhibit cyclooxygenase-1. The objective was to examine the relation between all-cause mortality and the concentrations of urinary 11-dehydro thromboxane B2 (11dhTxB2) and 8-IsoPGF2alpha in patients with stable coronary artery disease (CAD). METHODS: The data for this analysis are from a prospective study in which patients were categorized into four groups based on the median values of 11dhTxB2 and 8-IsoPGF2alpha. RESULTS: There were 447 patients included in this analysis with a median (range) age of 66 (37-91) years. The median (range) values of 11dhTxB2 and 8-IsoPGF2alpha were 1404.1 (344.2-68296.1) and 1477.9 (356.7-19256.3), respectively. A total of 67 (14.9%) patients died over a median follow-up of 1149 days. The reference group for the Cox proportional hazards survival analysis was patients with values of 11dhTxB2 and 8-IsoPGF2alpha below their corresponding medians. Adjusting for the age and sex, patients with values of 11dhTxB2 greater than the median had a significantly higher risk of mortality when compared with the reference group (high 11dhTxB2 and low 8-IsoPGF2alphaadj: hazard ratio: 3.2, 95% confidence interval: 1.6-6.6, P=0.002; high 11dhTxB2 and 8-IsoPGF2alphaadj: hazard ratio: 3.6, 95% confidence interval: 1.8-7.3, P<0.001). The findings were similar when we adjusted for the comorbidities of cancer, kidney function, and ejection fraction. CONCLUSION: We found that 11dhTxB2 appears to be a better prognostic marker for mortality as compared with 8-IsoPGF2alpha, suggesting aspirin resistance itself is a stronger independent determinant of death in CAD patients treated with aspirin.