Abstract:Objective Health care associated pneumonia (HCAP) has been proposed as a new category of pneumonia. This study aimed to analyze the clinical characteristics and risk factors for poor prognesis of HCAP in the elderly. Methods We conducted a retrospective observational study on 89 elderly HCAP patients. We compared the baseline characteristics, comorbidities, pathogen distribu-tion, antibiotics, and clinical outcomes between survival and dead patients. Multivariate logistic regression analysis was used to identify the risk factors for treatment failure of HCAP. Results A total of 89 HCAP patients were divided into survival group(61 patients, 68.5%) and death group (28 patients, 31.5%). The incidences of cerebrovascular diseases and chronic kidney diseases were higher in death patients than in survival patients. There were more patients with respiratory rate ≥30 breaths/min, heart rate ≥100 beats/min, systolic blood pressure <90 mmHg and altered mental station in death group than in survival group. There was no difference in fever, cough and expectoration. The most common causative organisms in both groups were pseudomonas aeruginosa, staphylococcus aureus and acinetobacter baumannii. Initial inappropriate antibiotics administration were more frequent in dead patients than in survival patients. Based on multivariate logistic analysis, respiratory rate≥30 breaths/min, systolic blood pressure<90 mmHg, class 5 pneumonia severity index(PSI), chronic kidney diseases, and inflammatory infiltration of two or more lobes of lungs were independent risk factors for treatment failure of HCAP in elderly patients. Conclusions HCAP in elderly patients is characterized by atypical symptoms, complex pathogens, high drug resistance, severe condition, and treatment difficulty. Its treatment and diagnosis need to be strengthened by further studies.