Risk factors for acute stroke-associated pneumonia and prediction of neutrophil-to-lymphocyte ratios

This study aimed to analyze the risk factors for stroke-associated pneumonia (SAP) and assess the predictive effect of neutrophil-to-lymphocyte ratio (NLR) on acute SAP. The study included acute stroke patients from April 2018 to June 2019. These patients were divided into the SAP and Non-SAP groups. The patients' history of chronic diseases was assessed, including history of hypertension, diabetes, hyperlipidemia, chronic lung disease, and current smoking status. The clinical characteristics of all studied cases were recorded, including the initial stroke type (cerebral infarction or cerebral hemorrhage), National Institute of Health Stroke Scale (NIHSS) score, indwelling nasogastric tubes, stroke-associated pneumonia within 7 days of hospitalization, and length of hospitalization. The study also recorded the laboratory testing data, including fasting blood glucose, triglyceride, total cholesterol, low-density lipoprotein cholesterol, glycosylated hemoglobin, and high-sensitivity C-reactive protein (hsCRP) as well as white blood cell (WBC), neutrophil, and lymphocyte counts. SPSS 19.0 was used for statistical analysis. A total of 328 eligible acute stroke patients were included. Among all participants, SAP occurred in 64 (19.5%) patients. In the SAP group, the patients were older, the proportion of cerebral hemorrhage was higher, the NIHSS score was higher, and more patients had nasogastric tubes (P < 0.05). Concomitantly, the blood glucose, hsCRP, WBC count, neutrophil count, and NLR of the SAP group were significantly higher than those of the Non-SAP group, whereas the lymphocyte count was significantly lower than that of the Non-SAP group (P < 0.05). Multivariable analysis of Binary Logistic regression revealed that stroke type (cerebral hemorrhage), indwelling gastric tube, and NLR were independent risk factors for SAP. Receiver operating characteristic curve analysis demonstrated that the area under the curve for the NLR's ability to predict SAP was 0.861. The optimal cutoff threshold, sensitivity, and specificity were 3.745, 0.891, and 0.727, respectively. The risk factors for SAP were multifaceted. Cerebral hemorrhage, indwelling nasogastric tube, and high NLR were independent risk factors. An early NLR had a predictive effect on the occurrence of SAP in patients with acute stroke.