Early Valuable Risk Stratification with Hemoglobin Level and Neutrophil to Lymphocyte Ratio in Patients with Non-ST-Elevation Myocardial Infarction Having an Early Invasive Strategy

ABSTRACT

OBJECTIVE: The complete blood count is the most widely available laboratory data in the early in-hospital period after acute myocardial infarction. We assessed the clinical utility of the combined use of hemoglobin (Hb) level and neutrophil to lymphocyte ratio (N/L) for early risk stratification in patients with non-ST-elevation myocardial infarction (STEMI). METHODS: We analyzed 6,157 consecutive patients with non-STEMI (65±12.4 years, male 69%) were included in the final analysis. Patients were categorized into 3 groups by using the median value of N/L (4.42) and the presence of anemia (Hb <13 mg/dL in men and <12 mg/dL in women) group I, low N/L & no anemia (n=3,170); group II, no group I or III (n=2,168); group III, high N/L & anemia (n=819). RESULTS: There were significant differences on clinical outcomes during 180-day follow-up among 3 groups. The prognostic discriminatory capacity of the combined use of Hb level and N/L was also significant in high-risk subgroups, such as patients with a renal dysfunction, multivessel coronary disease, low ejection fraction, and even in those having higher mortality risk based on the thrombolysis in myocardial infarction risk score. In a multi-variate logistic regression, after adjusting for multiple covariates, group III had higher incidence of major adverse cardiac events at 180-day (hazard ratio, 2.4; 95% confidence interval, 1.5–4.0;p≤0.001) compared with group I. CONCLUSIONS: The combined use of Hb level and N/L provides valuable timely information for early risk stratification in patients with non-STEMI.