The neutrophil-to-lymphocyte ratio is associated with bare-metal stent restenosis in STEMI patients treated with primary PCI

BackgroundThe clinical importance of complete blood count (CBC) parameters such as the neutrophil-to-lymphocyte ratio (NLR) has been shown in cardiovascular diseases. Stent restenosis (SR) is a major adverse event after stent implantation. In this study, we aimed to investigate the correlation of CBC parameters with SR rates after primary percutaneous coronary intervention (PCI).MethodsPatients who had undergone primary PCI for ST-segment elevation myocardial infarction (STEMI) and control angiography during follow-up were retrospectively recruited. Patients were categorized according to admission NLR tertiles, and clinical, hematological, and angiographic data were compared.ResultsA total of 404 patients (207 patients with SR and 197 patients without SR) were included in the study. Patients were categorized into three groups according to the tertiles of admission NLRs; the NLR was less than 3.38 in tertile 1 (n=134), between 3.38 and 6.26 in tertile 2 (n=135), and greater than 6.26 in tertile 3 (n=135). During a follow-up period of a median of 14 months (minimum 6 months, maximum 60 months) SR developed in 80 patients of tertile 3 (59%), 74 patients of tertile 2 (55%), and 53 patients of tertile 1 (40%), which were significantly different (P=0.01). According to multivariate Cox regression analysis, male sex, stent length (odds ratio 1.04, 95% confidence interval 1.01-1.06, P=0.01), admission NLRs (odds ratio 1.13, 95% confidence interval 1.08-1.19, P=0.01), and white blood cell and neutrophil counts remained the independent predictors of SR in the study population. Other CBC parameters and admission C-reactive protein, creatinine, and fasting glucose levels were not independently correlated with SR. On receiver operating curve analysis, admission NLRs higher than 3.84 were found to predict SR with a sensitivity of 73.4% and a specificity of 50.8% (area under the curve 0.604, P=0.01).ConclusionHigh NLR levels, white blood cell counts, and neutrophil counts at admission are independently correlated with SR after primary PCI.