BACKGROUND: Complex coronary lesions have been an understudied aspect of coronary artery disease in elderly patients. Oxidative stress and inflammation may be implicated in the pathogenesis of complex coronary lesions. OBJECTIVE: The aim of this study is to investigate the complex interplay between pro-oxidative stress response, pro-inflammatory response, and complex coronary lesions in elderly patients. METHODS: Enzyme-linked immunosorbent assays for the detection of serum biomarkers [reactive oxygen species (ROS), malondialdehyde (MDA), tumor necrosis factor-α (TNF-α), interferon-gamma (IFN-γ), superoxide dismutase (SOD) activity, total antioxidant capacity (TAC), transforming growth factor beta (TGF-β) and interleukin-4 (IL-4)] were performed in elderly patients with complex coronary lesions. RESULTS: The levels of pro-oxidative stress and pro-inflammatory markers (ROS, MDA, TNF-α and IFN-γ) were increased in the complex coronary lesion group when compared with the non-complex coronary lesion group (P <
0.01) in elderly patients. Anti-oxidative stress and anti-inflammatory markers (SOD activity, TAC, TGF-β, and IL-4) were decreased in the complex coronary lesion group when compared with the non-complex coronary lesion group (P <
0.01) in elderly patients. CONCLUSION: Our findings suggest that the pathogenesis of complex coronary lesions may involve pro-oxidant/anti-oxidant and pro-inflammation/anti-inflammation imbalance, as well as the interplay between oxidative stress and inflammation in elderly patients.