Associations of oxidative stress biomarkers with SYNTAX and ACEF risk scores in acute myocardial infarction: A cross-sectional study

Although oxidative stress plays a key role in the pathophysiology of acute myocardial infarction (AMI), its association with clinical risk-scoring systems (SYNTAX/ACEF) remains limited. This study examined the relationships between oxidative stress biomarkers and risk scores in patients with AMI, using bootstrap validation to evaluate statistical reliability. This cross-sectional study included 207 participants: 65 with STEMI, 62 with NSTEMI, and 80 controls. Oxidative stress biomarkers (malondialdehyde [MDA], protein carbonyl [PCO], total sulfhydryl [TSH], glutathione S-transferase [GST], glutathione reductase [GR], glutathione peroxidase [GPx], and reduced glutathione [GSH]) were measured using spectrophotometry. The SYNTAX and ACEF scores were calculated for patients with AMI. Statistical analyses included Pearson correlation, multivariate linear regression, and bootstrap resampling for validation. AMI patients exhibited significantly lower antioxidant parameters (TSH, GST, GR, GPx, and GSH; all P < .001) and higher levels of oxidative stress markers (MDA and PCO; both P < .001) than controls. Strong positive correlations were observed between SYNTAX and ACEF scores in both STEMI (R = 0.72, 95% confidence interval [95% CI]: 0.65-0.78) and NSTEMI groups (R = 0.69, 95% CI: 0.61-0.76). MDA and PCO showed strong positive correlations with both scoring systems in all patient groups. Bootstrap validation revealed a hierarchy of biomarker reliability: MDA, PCO, and GST demonstrated consistent stability in all analyses, whereas GPx and GSH showed subtype-specific patterns with lower reliability, especially in NSTEMI patients. Multivariate analysis identified age, MDA, PCO, GST, GR, and GSH as independent predictors of SYNTAX score (R2 = 0.78), while only age and eGFR predicted ACEF score (R2 = 0.65). Oxidative stress biomarkers were strongly correlated with clinical risk scores in patients with AMI. Among these, MDA, PCO, and GST demonstrated the most consistent associations with anatomical complexity. While these findings suggest that integrating validated oxidative stress biomarkers into existing scoring systems may help refine prognostic accuracy and guide personalized treatment strategies for AMI, further prospective validation is required.