This multinational trial aimed to characterize the “frequent exacerbator” asthma phenotype and to identify risk factors associated with exacerbations.
93 severe asthmatics and 76 mild-to-moderate patients were prospectively followed for 1 year. During the study, 104 exacerbations were recorded in the severe asthmatics group and 18 in the mild-to-moderate group.
Frequent exacerbators were characterized by:
- use of higher doses of inhaled (1700 vs. 800 μg) and oral (6.7 vs. 1.7 mg) glucocorticosteroids
- worse asthma control (ACQ score 2.3 vs. 1.4)
- lower quality of life
- higher sputum eosinophils (25.7% vs. 8.2%)
- more rapid decline in FEV1 /FVC ratio
- exhaled NO greater than 45 p.p.b. and a history of smoking were associated with an increased risk of frequent exacerbations (odds ratios: 4.32 and 2.90 respectively)
The researchers attempted to characterize a subphenotype of asthma subjects - frequent exacerbators - who are significantly more prone to exacerbations. Patients with FeNO > 45 p.p.b. and a history of smoking are at increased risk of frequent exacerbations and require close monitoring in clinical practice.
Frequent exacerbators - a distinct phenotype of severe asthma. Kupczyk M, Ten Brinke A, Sterk PJ, Bel EH, Papi A, Chanez P, Nizankowska-Mogilnicka E, Gjomarkaj M, Gaga M, Brusselle G, Dahlén B, Dahlén SE; BIOAIR investigators. Clin Exp Allergy. 2014 Feb;44(2):212-21. doi: 10.1111/cea.12179.
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