Platelet-to-lymphocyte ratio relates to poor prognosis in elderly patients with acute myocardial infarction

Background The platelet to lymphocyte ratio (PLR) is a novel biomarker to predict the prognosis of acute myocardial infarction (AMI) patients. Aim The study aimed to evaluate the in-hospital outcomes of elderly patients with AMI and assessed the prognostic value of PLR on in-hospital adverse events. Methods A total of 1,001 patients were divided into an older group ( n = 560) and a younger group ( n = 441) based on age ≥ 60 years and successfully underwent primary percutaneous coronary intervention (PCI) within 12 h after presentation. Total white blood cells (WBCs), neutrophils, lymphocytes, and platelets counts were measured at admission. Results The incidence of heart rupture, acute heart failure, total adverse events, and death resulting from all events were significantly higher in patients ≥ 60 years than in younger patients, whereas the incidence of postoperative angina and reinfarction were similar between groups. Regarding blood counts, total white blood cells, neutrophils, lymphocytes, and platelets were lower in the older group than in the younger group. The platelet-to-lymphocyte ratio (PLR) was significantly higher in the older group. In receiver operating characteristic curve analysis, high PLR > 147 predicted adverse events (specificity 72% and sensitivity 63%). In multiple logistic regression analysis, age, hypertension, and PLR were identified as independent predictors of adverse events. Conclusions The in-hospital outcomes of elderly patients with acute myocardial infarction were poor. PLR was an independent risk factor for in-hospital adverse events, which suggested that strong inflammation and prothrombotic status may contribute to the poor prognoses of elderly patients.