Abstract
BACKGROUND: Chronic obstructive pulmonary disease (COPD) is increasingly recognized as a disorder influenced by the respiratory microbiota. Microbial dysbiosis has been linked to disease progression, inflammation, and clinical outcomes. However, a comprehensive overview of the global research landscape and evolving themes in this field is still lacking. METHODS: Publications on COPD and respiratory microbiota were retrieved from the Web of Science Core Collection (WoSCC) and Scopus databases. Bibliometric analyses, including publication trends, co-authorship networks, keyword co-occurrence, citation bursts, and thematic evolution, were conducted using VOSviewer, CiteSpace, and the bibliometrix package in R. RESULTS: Between 2001 and 2025, 296 publications were identified in WoSCC and 433 in Scopus, reflecting a sustained growth in research output. Keyword co-occurrence and clustering analyses revealed three main research hotspots: (1) respiratory microbiota composition and dynamics, (2) pathogen colonization and inflammation-related processes, and (3) clinically relevant outcomes. Citation burst and thematic evolution analyses demonstrated a clear temporal shift from pathogen-centered studies toward microbiota-based, dynamic, and clinically oriented research paradigms. International collaboration is increasingly prominent, with China, the USA, and the UK leading in productivity and citation impact. CONCLUSION: This bibliometric study systematically delineates the intellectual structure and evolving trends of COPD-related respiratory microbiota research. Our findings highlight the maturation of the field, reveal emerging research directions such as multi-omics integration and gut–lung axis interactions, and provide a quantitative reference for guiding future translational and microbiota-focused studies in COPD.