Platelet-lymphocyte Ratio Predicts In-hospital Mortality in Elderly Patients with Acute Myocardial Infarction

Abstract

Background Important predictive value of platelet-lymphocyte ratio (PLR) for adverse outcomes of cardiovascular disease has been proved in previous studies, however, the predictive value of PLR for short-term prognosis in elderly patients with acute myocardial infarction (AMI) remains to be explored. Objective To determine the predictive ability of PLR for mortality risk during hospitalization in elderly patients with AMI. Methods The medical history data of 1 423 elderly patients with AMI treated in the Department of Cardiology of the Second Hospital of Dalian Medical University from December 2015 to December 2021 was retrospectively collected, mainly including gender, age, BMI, blood pressure classification, glycated hemoglobin, platelet count, neutrophil count, lymphocyte count, estimated glomerular filtration rate, lipid related indices, the combination of heart failure and diabetes, the use of statins and antiplatelet agents during hospitalization, with the final outcome defined as all-cause death during hospitalization. The included patients were divided into the non-death group (n=1 315) and death group (n=108) according to the occurrence of death. ROC curve was used to determine the predictive ability of PLR for in-hospital mortality risk in elderly patients with AMI, and the clinical application value of PLR and its combined indicators by decision curve analysis (DCA) . Results There were significant differences in age, BMI, PLR, white blood cell count, neutrophil count, lymphocyte count, red blood cell count, hemoglobin, fasting blood glucose level, AST, TG, CTNI, eGFR grade, proportion of heart failure, proportion of antiplatelet drugs, and proportion of lipid-lowering drugs between the death group and the non-death group (P<0.05). The area under the ROC curve of PLR for predicting the risk of in-hospital mortality in elderly AMI patients was 0.661 (P<0.001) ; AUC when PLR was combined with CK-MB or CTNI was 0.705 and 0.779 (P<0.001), respectively. The results of decision curve analysis based on Bootstrap method showed that the risk threshold of PLR between 6% and 82% and the risk threshold of PLR combined with CTNI between 2% and 86% could produce large net benefits and have clinical application value. Conclusion PLR can effectively predict the risk of in-hospital death in elderly patients with AMI, and this predictive ability is significantly improved after combined CTNI.

Keywords

• myocardial infarction|platelet to lymphocyte ratio|in-hospital death|death|forecasting