Stroke-Associated Pneumonia: Asia-Pacific Perspective

Stroke-associated pneumonia (SAP) is a frequent complication of acute ischemic stroke (AIS) and is associated with increased mortality, disability, length of hospital stay, and healthcare costs. Global pooled prevalence estimates of SAP range from 12.3% to 14.3%, but reported rates vary across the APAC region. Given that China alone accounted for 4.1 million incident stroke cases in 2021, representing one-third of the global stroke burden, SAP represents a substantial clinical and health-system challenge across the region.

Reported SAP prevalence varied substantially across APAC cohorts, ranging from 2.6% in Japan, 5.5% in Singapore, 10.4% in the China National Stroke Registry and up to 15.8% in Thailand, reflecting differences in diagnostic criteria, case mix, stroke severity, and care settings. SAP frequently occurs early after stroke; in one Japanese cohort, 77.3% of cases developed within 72 hours. Stroke severity was the most consistently reported risk factor, alongside dysphagia, mechanical ventilation, older age, and comorbid disease. Evidence supports a multifactorial pathogenesis involving stroke-induced immunodepression and gut-brain-lung axis disruption. Large international trials of universal antibiotic prophylaxis have not demonstrated reductions in SAP or improvements in functional outcomes. In APAC, preventive care interventions have produced variable results; notably, a Chinese assessor-blinded randomized controlled trial of tailored oral health care reported SAP in 10.26% of the intervention group compared with 32.43% of controls. Overall, heterogeneity in SAP definitions, study populations, and intervention designs limits direct comparison between studies.

SAP is a common complication of AIS in the APAC region, although reported prevalence varies considerably between studies and according to diagnostic criteria applied. Stroke severity, dysphagia, mechanical ventilation, older age and comorbidities are frequently reported risk factors. Evidence for preventative interventions remains heterogenous, highlighting the need for standardised diagnostic criteria and further evaluation of risk-stratification tools and multidisciplinary prevention strategies in resource-diverse APAC settings.