Global research trends on PM2.5 and cardiovascular disease: a 20-year bibliometric analysis (2004-2023)

Background: While PM2.5’s cardiovascular effects are increasingly recognized, but bibliometric analyses of this research landscape remain limited. This study systematically evaluates global research trends, collaborations, and knowledge gaps. Methods: We analyzed 2,618 publications (2004–2023) from Web of Science using VOSviewer and CiteSpace to assess outputs, collaborations, journals, and research hotspots. Results: Publications grew steadily, dominated by China and the U.S. (82.4%). U.S. studies had higher citation impact. Harvard University was most productive. Key journals were Environmental Research and Circulation. Research hotspots included hypertension, inflammation, and lipid metabolism. Emerging frontiers involve PM2.5 constituents and gene–environment interactions. Conclusion: This first bibliometric study highlights fragmentation and imbalances in PM2.5–cardiology research. Findings underscore the need for standardized exposure assessments, interdisciplinary collaboration, and targeted studies to guide policy and clinical practice.