Malondialdehyde Outperforms Myeloperoxidase in Identifying Obstructive Coronary Artery Disease: A Cross-Sectional Angiographic Study

Abstract

Background: Oxidative stress plays a central role in coronary atherosclerosis. This study evaluated serum malondialdehyde (MDA) and myeloperoxidase (MPO) in relation to the angiographic severity of coronary artery disease (CAD), and assessed their diagnostic performance.
Methods: In this cross-sectional study, 254 patients aged ≥40 years undergoing coronary angiography were classified into five groups: no CAD (Group I, n = 21), non-obstructive CAD (Group II, n = 22), and single-, double- and triple-vessel/left main obstructive CAD (Groups III–V; n = 89, 70 and 52). Disease severity was quantified using the Gensini score. Serum MDA and MPO were measured by ELISA. Statistical analysis included the Kruskal-Wallis test, Spearman's correlation, ordinal logistic regression and receiver operating characteristic (ROC) curve analysis.
Results: Median MDA increased from 75.2 ng/mL in Group I to 242.6 ng/mL in Group V, and MPO from 6.8 to 15.7 ng/mL (both p < 0.001). Both markers correlated positively with the Gensini score (MDA ρ = 0.599; MPO ρ = 0.455; p < 0.001), and MDA correlated inversely with HDL-C. On ordinal logistic regression, MDA (p = 0.001) and MPO (p = 0.016) were independently associated with CAD severity. MDA showed excellent discrimination for CAD versus non-CAD (AUC 0.944; sensitivity 87.6%, specificity 90.5% at ≥116.96 ng/mL) and for obstructive CAD (AUC 0.915), while MPO showed good discrimination (AUC 0.878 and 0.803, respectively).
Conclusion: Serum MDA and MPO rise in a graded manner with the angiographic severity of CAD and are independently associated with disease burden. MDA showed superior diagnostic accuracy and may serve as a useful biomarker for identifying CAD and obstructive coronary disease.