Page 76 - Comprehensive treatment of patients with glucocorticoid-dependent severe asthma

Chapter 4
Introduction
Severe asthma is a life-threatening disease currently understood as a complex interaction of clinical, physiological and inflammatory characteristics resulting in different phenotypes. Over the last decade studies have identified at least three different severe asthma phenotypes, including severe atopic asthma, persistent eosinophilic asthma (formerly called ‘intrinsic’ asthma) and asthma associated with morbid obesity [1-4]. This phenotypic heterogeneity is mirrored by different responses to asthma treatment. For example, persistent eosinophilic asthma usually responds to high dose inhaled or oral corticosteroid treatment [1], whereas the obese phenotype typically does not [5], which supports the need for targeted treatment [6;7].
Apart from new biological pharmacological targeted treatments [8;9], also non- pharmacological treatment strategies such as targeting airway smooth muscle directly with bronchial thermoplasty [10], optimizing the management process with telemonitoring [11], or treating the patient in a low-trigger environment at high-altitude [12] have been shown to be beneficial for patients with severe asthma.
High-altitude climate therapy involves exposure to conditions of altitude ≥1500m above sea level [13] and it was previously believed to be of benefit specifically to patients with atopic asthma [14] but recent evidence shows that atopy is not the only driver for a successful outcome [15-18]. The determinants of a successful outcome of high-altitude climate therapy are still unclear. From clinical experience it appears that also the type of response to high-altitude climate therapy differs between patients. Some have a more pronounced improvement in lung function [13], whereas others boost their exercise tolerance or are able to taper their dose of oral corticosteroids.
In the present study, we investigated whether typical clinical, functional and inflammatory characteristics of patients with severe asthma can predict a specific beneficial outcome of high-altitude climate therapy.
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