Abstract: Objective To evaluate clinical significance and application outcomes of using the neutrophil-to-lymphocyte count ratio (NLR) and C-reactive protein to albumin ratio (CRP/ALB) in the aged patients hospitalized with acute exacerbation of chronic obstructive pulmonary disease(AECOPD). Methods 172 aged patients with AECOPD who were hospitalized in the Department of Geriatrics and Department of Respiratory Medicine of the Second People's Hospital of Hefei from January 2016 to January 2020 were recruited. According to clinical outcomes, they were divided into survival group (n=155) and death group (n=17). Survival group was divided into groups according to hospitalization days of more or less than ten days. Parameters were got through contrast of clinical and laboratory test indexes of patients in each group. Logistic regression and receiver operating characteristic curve (ROC) were used to analyze the risk factors and their correlation with in-hospital mortality. Results Among 172 aged AECOPD in-patients, 17 patients died during hospitalization with mortality as 9.88%. There were differences between the death group and the survival group in NLR, CRP, CRP/ALB, red blood cell distribution width (RDW), cigarette consumption, community acquired pneumonia (CAP) and various comorbidities. Parameters above mentioned in the death group was higher than the survival group(P＜0.01). At the same time, 155 aged patients with AECOPD who survived and discharged were divided into two subgroups according to the hospitalization ≥10 days and ＜10 days. It was found that NLR, CRP, CRP/ALB, RDW, smoking and CAP in group with hospitalization longer than ten days were significantly more common than those in group of less than ten days hospitalization(P＜0.01). The Logistic regression analysis of NLR, CRP, CRP/ALB and RDW showed that NLR and CRP/ALB might be independent risk factors for in-hospital death. From the analysis of the ROC, the cut-off value of NLR was 11.04, the area under the curve was 77%, and the cut-off value of CRP/ALB was 1.12, and the area under the curve was 65%. Conclusions NLR and CRP/ALB may be the risk factors for in-hospital death of aged patients with AECOPD, which are associated with poor prognosis.

Key words: acute exacerbation of chronic obstructive pulmonary disease(AECOPD), neutrophil-to-lymphocyte count ratio, C-reactive protein, mortality, prognosis