Abstract: Objective To investigate the risk factors of stroke-associated pneumonia(SAP) and its impact on early outcome in elderly patients with first-onset cerebral infarction(CI). 
Methods According to the Xi′an Stroke Registration Study, the elderly patients with first-onsetCI admitted to four first-class tertiary hospitals in Xi′an City were included. They were divided into non-SAP group and SAP group based to the occurrence of SAP in hospital, and the differences in baseline clinical characteristics of the two groups were compared. Multivariate Logistic regression model was used to analyze the risk factors for SAP and its impact on early outcome events(poor outcome［mRS score: 3-6 points］, stroke recurrence and death) in elderly patients with first-onset CI. 
Results A total of 1 039 patients with first-onset CI were enrolled in the study, with an average age of (71.58±7.62) years, including 577 males(55.7%) and occurrence of SAP in 64 cases(6.2%).Multivariate Logistic regression model showed that age(OR=1.073, 95%CI: 1.025-1.123, P＜0.001), National Institutes of Health Stroke Scale（NIHSS） score on admission(OR=1.114, 95%CI: 1.047-1.186, P＜0.001), dysphagia(OR=3.042, 95%CI: 1.523-6.084, P=0.002)and white blood cell(WBC) count (OR=1.153, 95%CI: 1.023-1.299, P=0.020)were independent risk factors for SAP in elderly patients with first-onset CI. The incidence of SAP was associated with a higher risk of early poor outcome(OR=3.194, 95%CI: 1.516-6.730, P=0.002), stroke recurrence(OR=3.368, 95%CI: 1.271-8.926, P=0.015) and death(OR=2.706, 95%CI: 1.111-6.588, P=0.028). 
Conclusion Age, NIHSS score on admission, dysphagia and WBC count are independent risk factors for SAP in elderly patients with first-onset CI. The occurrence of SAP significantly increases the risk of poor early prognosis in these patients.

Key words: cerebrali nfarction, pneumonia, stroke