Red Blood Cell Distribution Width, Neutrophil-to-Lymphocyte Ratio, and In-Hospital Mortality in Dyspneic Patients Admitted to the Emergency Department

Red blood cell distribution width (RDW) and neutrophil-to-lymphocyte ratio (NLR) have shown a prognostic value in various clinical settings. We aimed to investigate the association between RDW, NLR, and in-hospital mortality in patients with dyspnea. In this retrospective study with the Medical Information Mart for Intensive Care III database (version 1.4), adult patients who came to the emergency department with dyspnea were included. Patients' comorbidities, hematological parameters within the first 48 hours after admission to the emergency department, and in-hospital mortality were extracted. The relationships between RDW, NLR, and in-hospital mortality were analyzed with the receiver operating characteristic (ROC) curve analysis and multivariate logistic regression model. We found that hospital survivors had significantly lower NLR than those who died. However, RDW was not significantly increased in patients who died during the hospitalization. The area under the ROC curve of NLR for predicting in-hospital mortality was 0.62. On multivariate analysis, NLR was not independently associated with in-hospital mortality. On further analysis, lymphocyte percentage was independently associated with in-hospital mortality, with an odds ratio of 0.56. Therefore, we concluded that RDW and NLR are not reliable parameters to predict in-hospital mortality in critically ill patients admitted to the emergency department with dyspnea.