Clinical and Pathophysiological Characteristics of Severe Asthma

Kim, Sang Heon

Abstract

Severe asthma is characterized by poor asthma control and frequent exacerbation despite high degree of medication. Severe asthma leads to not only increased morbidity and mortality but high socioeconomic burden. To date, several research networks have been organized to understand the clinical and pathophysiological characteristics of severe asthma. These groups organized multicenter registries and collected both clinical and biological information. The results of these groups revealed that severe asthma is a very heterogeneous entity, which could not be defined based on a single feature. Various phenotypes of asthma has been identified based on clinical, inflammatory and immune responses. To understand severe asthma more drastically in consideration of many phenotypes, cluster analysis and endotyping severe asthma have been tried. Although uncontrolled inflammation and airway remodeling underlies the development of severe asthma, much is not known about its pathomechanisms. This review discusses the current understanding of the clinical and pathogenic mechanisms of severe asthma based on the recent publications.