The risk of stroke-related pneumonia: a systematic review of peripheral immunodepression markers

INTRODUCTION: Ischemic stroke (IS)-associated pneumonia is a leading cause of mortality after stroke, driven by peripheral immune imbalance. This systematic review evaluates immunosuppression markers associated with pneumonia following IS in clinical studies. METHODS: Following PRISMA guidelines, we searched PubMed/MEDLINE, EMBASE, and LILACS databases until March 2024. Inclusion criteria comprised clinical studies assessing IS-related immunosuppression and pneumonia, excluding in vitro and animal studies. Study quality was assessed using the Newcastle-Ottawa Scale. RESULTS: A total of 32 studies met the inclusion criteria, analyzing 1,833 post-stroke patients. Findings indicate that increased interleukin-6 (IL-6), interleukin-10 (IL-10), and C-reactive protein (CRP) levels, alongside decreased repulsive guidance molecule A (RGM-A), are early indicators of post-stroke pneumonia. Meta-analysis was not conducted due to heterogeneity in study methodologies and populations. CONCLUSIONS: PROSPERO CRD42024543108.