A Bibliometric Analysis of Pulmonary Function Testing in Differentiating Asthma From COPD: Trends, Impact, and Emerging Research Areas

Background: Distinguishing between asthma and chronic obstructive pulmonary disease (COPD) remains a clinical challenge due to overlapping symptoms and pulmonary function test (PFT) results. Accurate differentiation is crucial for effective treatment and optimal patient care. This study employs bibliometric analysis to assess research trends, impact, and emerging areas in the use of PFTs for differentiating asthma from COPD. Methods: A systematic search was conducted in the Web of Science Core Collection, including both asthma- and COPD-related terms to reflect clinical overlap, identifying publications from 1989 to November 2024. Data were analyzed using VOSviewer, CiteSpace, Excel, and Biblioshiny to evaluate publication trends, influential authors, key research themes, and international collaboration networks. Results: The analysis included 241 original research and review articles. Research activity increased significantly after 2006, peaking in 2022. The United States and England were the leading contributors, with major academic institutions and AstraZeneca playing key roles. Keywords such as “spirometry”, “diagnosis”, and “bronchodilator response” emerged as major research trends. Co-citation analysis identified the European Respiratory Journal as the most influential source. Conclusion: Bibliometric analysis highlights a growing body of research emphasizing the role of PFTs in differentiating asthma from COPD. While spirometry remains the gold standard, recent trends show increasing interest in novel diagnostic approaches. Further studies are needed to refine diagnostic criteria and improve clinical decision-making. Our findings underscore the novelty of this bibliometric analysis in mapping global research dynamics and highlight potential clinical implications for refining diagnostic strategies in asthma and COPD.