Hotspots and trends of microglia in ischemic stroke: A bibliometric analysis from 1998 to 2024

BACKGROUND: Ischemic stroke (IS) represents a predominant cause of disability globally, characterized by significant neuroinflammatory responses facilitated by microglia, the resident immune cells of the central nervous system. A comprehensive understanding the current research landscape in this field is essential for guiding future inquiries. However, a systematic, quantitative panorama analysis of this intersecting field is lacking. This study aims to address this knowledge gap by conducting a bibliometric analysis of publications retrieved from the Web of Science Core Collection database, elucidating historical developments, collaboration networks, and emerging frontiers. OBJECTIVE: This study endeavors to perform a comprehensive bibliometric analysis of microglia research in IS, with the aim of elucidating historical developments, identifying current research frontiers, and proposing future directions through a quantitative assessment of publication trends, collaboration networks, and the evolution of conceptual frameworks. METHODS: Utilizing controlled vocabulary terms for IS and microglia, we conducted a systematic search of the Web of Science Core Collection database. After applying exclusion criteria, our analysis included 5709 publications (4859 articles; 850 reviews). We employed Bibliometrix R, VOSviewer, and CiteSpace for advanced bibliometric analysis. RESULTS: The annual publication count showed exponential growth, with a compound annual growth rate of 14.6% over the past 5 years (2020-2024), indicating robust research momentum. Systematic reviews and meta-analyses accounted for 14.9% of the total, highlighting the growing importance of integrative evidence. China (n = 1852) and the United States (n = 1723) leading in research contributions. Capital Medical University emerged as the most prolific institution (n = 217). Journal of Neuroinflammation was the primary publication venue (n = 142), while Stroke had the highest citation count (8742 citations). Moo-Ho Won was the most productive author (n = 68), and Iadecola C. was the most co-cited researcher (n = 1024). Keyword analysis identified "microglia polarization" (burst strength = 36.5), "NLR family pyrin domain containing 3 inflammasome" (burst strength = 32.1), and "extracellular vesicles" (burst strength = 28.7) as emerging research frontiers. CONCLUSION: Our analysis outlines 3 key research trajectories, molecular mechanisms of microglia activation, particularly NLR family pyrin domain containing 3-mediated pathways; phenotypic modulation of microglia during stroke recovery; and novel roles in angiogenesis and immunomodulation. The emergence of "gut-microbiota-brain axis" and "mitochondrial transfer" as new research themes offers promising directions for investigation. These findings provide a strategic framework for prioritizing research on neuroinflammation and neurorepair after stroke.