United airway disease

Abstract

The unified airway theory and the concept of united airway disease (UAD) are relatively recent. However, there is a body of growing evidence to support it. This book chapter will delve into the anatomical, epidemiological, pathophysiological, and clinical data that have been instrumental in expanding this theory. In addition, the increasing focus on precision and personalised medicine has allowed for the description of new endophenotypes involving both upper and lower airways, which will further support the concept of UAD and allow for optimised diagnostic and management pathways (e.g., targeted treatments like biologics or allergen-specific immunotherapy). This chapter will explore those endophenotypes involving allergic rhinitis, as other chapters in this book will address most of the other endophenotypes described here.