characteristics of stroke associated pneumonia by stroke subtypes incidence time course potential risk and microbiological pathogen

Abstract Objective: To compare incidence, time course, potential risk and microbiological pathogens of SAP by stroke subtypes. Methods: This study is based on a cohort (in-hospital Medical Complication after Acute Stroke, iMCAS), which consecutively enrolled patients with Acute Ischemic Stroke (AIS), Intracerebral Hemorrhage (ICH) and Subarachnoid Hemorrhage (SAH) admitted to stroke unit of Beijing Tiantan hospital From January 2014 to December 2016. In-hospital SAP was diagnosed based on the criteria for hospital-acquired pneumonia of Center for Disease Control and Prevention. Results: A total number of 1771 patients (1129 of AIS, 314 of ICH and 329 of SAH) were enrolled in the iMCAS. The mean age was 57.1±12.9 and 27.5% were female. The median length of stay was 14 days (Interquartile Range [IQR], 11-16). In-hospital SAP after AIS, SAH and ICH was 86 (7.6%), 55 (16.8%) and 59 (18.8%), respectively. The median time from onset to diagnosis of SAP after AIS, SAH and ICH were 4 days (IQR:2-7), 5 days (IQR:3-7) and 3 days (IQR: 2-5), respectively. After adjusting for potential confounders, patients with ICH (OR=2.050; 95% CI=1.241-3.388; P=0.005) and SAH (OR=4.903; 95% CI=2.788- 8.623; P<0.001) had significantly higher risk of SAP than those with AIS. Microbiological assessment was established in nearly half patients by sputum culture and three quarters was identified with Gram-negative bacteria. Overall, 57.7% patients with positive sputum culture had multi-drug resistant pathogen. The distribution of causative bacteria was not significant different by subtypes. Conclusion: Patients with hemorrhagic stroke (ICH and SAH) have significantly higher risk of in-hospital SAP than patients with AIS. Further studies on molecular mechanisms are warranted.