Higher Neutrophil/Lymphocyte Ratio Is Related to Lower Ejection Fraction and Higher Long-term All-Cause Mortality in ST-Elevation Myocardial Infarction Patients

Abstract Background Neutrophil/lymphocyte ratio (NLR) is a novel biomarker that can single out individuals at risk for vascular events. We assessed whether NLR provides additive prognostic value in patients with ST-elevation myocardial infarction (STEMI). Methods NLR was computed from the absolute values of neutrophils and lymphocytes from the complete blood count of patients who underwent primary coronary angioplasty for STEMI. The cohort was divided into 2 groups according to NLR (NLR ≥ 6.5%, NLR < 6.5%) using χ2 automatic interaction detection. The association between NLR and in-hospital clinical complications and left ventricular ejection fraction (EF) was assessed using logistic regression. The association between NLR, 30-day and 5-year all-cause mortality were analyzed using Cox regression models, adjusting for potential clinical, metabolic, and inflammatory confounders. Results In a group of 538 consecutive STEMI patients, high NLR (NLR ≥ 6.5%) was independently associated with increased 30-day and 5-years mortality rates (odds ratio, 15.8; 95% confidence interval, 1.6-154; P = 0.018; and hazard ratio, 2.2; 95% confidence interval, 1.04-4.8; P = 0.039, respectively). High NLR was also independently associated with lower EF (49 ± 8 vs 46 ± 8; P < 0.001) and fewer hospital complications. Conclusions In patients presenting with STEMI, high NLR was independently associated with lower EF, fewer hospital complications, and higher mortality rates up to 5 years. NLR value appears additive to conventional risk factors and commonly used biomarkers.