Global research landscape and emerging trends of respiratory microbiota and asthma: a bibliometric analysis

Asthma is a heterogeneous chronic airway disease in which respiratory microbiota is increasingly recognized as key contributors to airway inflammation, immune regulation, and clinical phenotypes. However, the rapid growth of publications has resulted in a fragmented knowledge landscape, hindering the identification of core contributors and emerging research directions.

A bibliometric analysis was conducted using publications from the Web of Science Core Collection (WoSCC) and Scopus (2000-2025). Bibliometrix, VOSviewer, and CiteSpace were applied independently to each database to assess publication trends, collaboration networks, co-citation structures, keyword co-occurrence, and burst dynamics, enabling cross-database validation.

A total of 516 WoSCC and 572 Scopus records were included. Both datasets showed consistent growth after 2015, with comparable annual growth rates. The United States, China, and the United Kingdom were leading contributors and central collaboration hubs. Core journals and co-citation patterns were highly concordant across databases. Three reproducible research themes were identified: respiratory microbiota dysbiosis, immune-microbiota interactions, and early-life microbial exposure. Temporal analyses consistently showed a shift toward phenotype-oriented and mechanistic research, with increasing focus on disease severity, immune regulation, and biomarker-related topics.

This dual-database bibliometric study provides a validated overview of the evolving research landscape of respiratory microbiota in asthma. The findings suggest a transition toward more integrative and mechanism-oriented research, offering a structured framework to guide future studies and methodological development.