Page 74 - Comprehensive treatment of patients with glucocorticoid-dependent severe asthma

Chapter 4
Abstract
Background: High-altitude climate therapy has been shown to benefit patients with severe asthma but it is not known which patients benefit most from this treatment. In the current study we aimed to identify clinical, functional and inflammatory predictors of favourable outcome of high altitude climate therapy.
Methods: This is a secondary analysis of a prospective cohort including 136 adult patients with a diagnosis of severe refractory asthma, referred to the Dutch Asthma Centre in Davos (1.600 MASL), Switzerland. They had assessments of medication usage, asthma related quality of life (AQLQ), asthma control, body mass index (BMI), sino-nasal symptoms, fatigue, lung function (FEV1), exercise tolerance, allergy and inflammation (FeNO, blood eosinophils) at entry and after 12 weeks treatment. Five clinically relevant outcomes were considered: AQLQ, oral corticosteroid (OCS) dose, FEV1, body mass index and blood eosinophils. Independent predictors of beneficial outcome were identified by multiple linear regression analysis.
Results: Lower blood eosinophil counts (p<0.01), younger age (p=0.02) and poorer asthma control (p<0.01) were independently associated with greater reduction in OCS dose. Lower fatigue score at baseline (p=0.01) was associated with greater weight loss (reduction in BMI). Higher levels of total IgE at baseline (p<0.01), and higher doses of inhaled corticosteroids (p=0.03) were associated with greater decreases in blood eosinophils. There were no predictors for improvement in AQLQ or FEV1.
Conclusions: The beneficial effect of high altitude climate therapy in adults with severe asthma can be predicted by patient characteristics, such as age, blood eosinophils and degree of asthma control before admission.
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