The United Airways Concept: Bidirectional Interactions Between the Upper and Lower Respiratory Tracts

Year 2025, Volume: 8 Issue: 2, 85 - 89, 31.08.2025

Imran Özdemir

https://doi.org/10.65396/ejra.1825480

Abstract

The upper and lower airways are anatomically connected and share immunological, physiological, and pathological features, which have led to the development of the “United Airways Concept” (UAC). This concept suggests a functional unity where disease processes in one area affect the other. Increasing evidence links upper airway diseases such as allergic rhinitis and chronic rhinosinusitis with lower airway conditions like asthma and chronic obstructive pulmonary disease (COPD), indicating that both airway segments should be viewed as a single structural and functional unit. This manuscript examines the pathophysiological mechanisms, clinical implications, and integrated management strategies within the united airways framework. The bidirectional relationship is supported by common embryological origin, histopathological findings, inflammatory pathways, and clinical observations. Recognizing this unity provides new insights for diagnosing, treating, and preventing chronic respiratory diseases.

Keywords

Upper Respiratory Tracts , Lower Respiratory Tracts , airways , united airways

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