Exploring global research trends in sublingual immunotherapy of allergic rhinitis: a comprehensive bibliometric analysis.

Abstract

Sublingual immunotherapy (SLIT) is a well-established, safe, and patient-friendly treatment for allergic rhinitis. This study aims to provide a comprehensive bibliometric analysis of global research trends and emerging hotspots in SLIT for allergic rhinitis. Relevant publications were sourced from the Web of Science Core Collection (1993-2024). VOSviewer, CiteSpace, and the R "bibliometrix" package were used to visualize research collaborations, leading contributors, and thematic developments. This analysis of 696 publications on SLIT for allergic rhinitis reveals a dynamic, collaborative field. The USA, China, and Italy led production, with the University of Genoa as the top institution. Research is organized into six clusters: immunological mechanisms, clinical efficacy, epidemiology/guidelines, pediatric research, disease classification, and real-world evidence.The focus has evolved over two decades from initial clinical efficacy studies toward understanding underlying immune mechanisms (highlighted by recent keyword bursts like "dendritic cells"), biomarker discovery, and specialized pediatric applications. There is also a strengthened emphasis on long-term management and real-world effectiveness. SLIT research is diversifying, marked by a growing emphasis on immunology, personalized and pediatric approaches, and practical outcomes, providing a robust foundation for optimizing future therapy. Allergic rhinitis, often called hay fever, causes sneezing, a runny or blocked nose, and itchy symptoms. Medicines can help control symptoms, but they do not change the underlying allergy. Sublingual immunotherapy is a longer-term treatment that places small amounts of an allergen under the tongue to help the immune system become less sensitive over time. Because many studies on this treatment have been published, it can be difficult to understand how the research field has developed and what topics are now receiving the most attention.In this study, we reviewed and analyzed published research on sublingual immunotherapy for allergic rhinitis using a method called bibliometric analysis. Instead of re-testing the treatment in patients, bibliometric analysis looks at patterns across the scientific literature, such as how many papers are published each year, which countries and institutions publish the most, which journals publish the research, and which topics are becoming more important.We analyzed 696 publications indexed in the Web of Science Core Collection from 1993 to 2024. We found that research output increased over time, with strong contributions from the United States, China, and Italy, and major involvement from both universities and companies. Research topics clustered into areas including treatment effectiveness and safety, immune mechanisms, guidelines and health policy, pediatric studies, and real-world outcomes such as adherence. Overall, the field is expanding and increasingly focused on long-term management, immune pathways, and practical use in everyday care.