Combined Neutrophil-to-Lymphocyte Ratio and CURB-65 Score as an Accurate Predictor of Mortality for Community-Acquired Pneumonia in the Elderly

Abstract

Ding-Yun Feng,* Xiao-Ling Zou,* Yu-Qi Zhou,* Wen-Bin Wu, Hai-Ling Yang, Tian-Tuo Zhang Department of Pulmonary and Critical Care Medicine, The Third Affiliated Hospital of Sun Yat-Sen University, Institute of Respiratory Diseases of Sun Yat-Sen University, Guangzhou, People’s Republic of China*These authors contributed equally to this workCorrespondence: Tian-Tuo ZhangDepartment of Pulmonary and Critical Care Medicine, Third Affiliated Hospital of Sun Yat-Sen University, Institute of Respiratory Diseases of Sun Yat-Sen University, 600 Tianhe Road, Guangzhou, 510630, People’s Republic of ChinaTel [phone]Email [email protected]: Community-acquired pneumonia (CAP) is common among the elderly; it typically has a poor prognosis and high mortality. This study evaluated the factors predicting CAP-related in-hospital mortality in the elderly to identify a simpler and more accurate predictor.Patients and Methods: This was a single-center, retrospective study. The data used in this study was collected from all older patients (≥ 65) with CAP admitted to our hospital between January 2012 and April 2020.Results: A total of 2028 older patients with CAP were included; 121 (5.97%) died in hospital. Of the patients in the study, 1267 (62.5%) were men and 261 (12.9%) had a history of malignant tumors. After performing univariate and multivariate Cox regression analyses, sex, history of malignant tumor, CURB-65 score, neutrophil-to-lymphocyte ratio (NLR), hemoglobin level, and NLR*CURB-65 levels were associated with CAP mortality. By comparing the area under the receiver operating characteristic (ROC) curves of the predicted factors, the NLR*CURB-65 level used to predict CAP mortality in the elderly was 0.755, and was superior to other measurements. All included patients were then dichotomized into two groups based on NLR*CURB-65 level (≤ 9.06 and > 9.06) according to the ROC analysis. Patients with a high NLR*CURB-65 level had higher in-hospital mortality than those with a low NLR*CURB-65 level. The two divided groups showed significant differences in age, sex, smoking history, comorbidity, and laboratory findings. This indicates that NLR*CURB-65 is a predictive index that could reflect the comprehensive condition of older patients with CAP.Conclusion: NLR*CURB-65 is a simpler and more accurate predictor of CAP-related in-hospital mortality in the elderly.Keywords: NLR*CURB-65, community-acquired pneumonia, mortality, predictor

Keywords

• nlr*curb-65
• community acquired pneumonia
• mortality
• predictor