Baseline Inflammatory Ratios and Anemia for Predicting Multivessel Coronary Artery Disease in Patients With ST-Elevation Myocardial Infarction

Abstract

Objective: To evaluate whether baseline neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and anemia are independently associated with multivessel coronary artery disease (MVD) and whether their addition to routinely available clinical variables improves the discrimination of MVD in patients presenting with ST-segment elevation myocardial infarction (STEMI). Methodology: This prospective observational study included 150 consecutive adult patients presenting with their first STEMI at two tertiary-care hospitals in Karachi, Pakistan, between January and June 2025. All participants underwent emergency coronary angiography during the index hospitalization. Baseline complete blood counts obtained before angiography were used to determine hemoglobin concentration and calculate NLR and PLR. Anemia was defined using World Health Organization sex-specific hemoglobin thresholds. MVD was defined as significant stenosis involving two or more major epicardial coronary arteries. Results: Among 150 patients (mean age 62.9 ± 10.4 years; 58.0% male), 132 (88.0%) had MVD and 64 (42.7%) had anemia. In the multivariable clinical model, increasing age (OR 1.058, 95% CI 1.001–1.118; p=0.045), male sex (OR 3.563, 95% CI 1.151–11.033; p=0.028), and higher troponin-I (OR 1.606, 95% CI 1.025–2.517; p=0.039) were independently associated with MVD. In contrast, NLR, PLR, and anemia were not independently associated with MVD (all p>0.05). The clinical model comprising age, sex, and troponin-I demonstrated good discrimination (AUC 0.816, 95% CI 0.729–0.903). Addition of NLR and anemia (AUC 0.825) or PLR and anemia (AUC 0.830) produced only small numerical increases in AUC that were not statistically significant compared with the clinical model alone (DeLong p=0.690 and p=0.542, respectively). Individual hematological biomarkers demonstrated poor discrimination for MVD. Conclusion: Baseline NLR, PLR, and anemia were not independently associated with multivessel coronary artery disease in patients presenting with STEMI and did not significantly improve discrimination beyond routinely available clinical variables. Age, male sex, and troponin-I were independently associated with MVD in this cohort. These findings do not support the use of NLR, PLR, or anemia as stand-alone markers for identifying angiographic multivessel disease in STEMI, although validation in larger and more balanced multicenter cohorts is warranted.