Small airway dysfunction in asthmatic patients treated with as-needed SABA monotherapy: A perfect storm - 04/03/23
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Abstract |
Background |
Short-acting beta agonist (SABA)-only treatment is associated with poor asthma control and adverse clinical outcomes. The importance of small airway dysfunction (SAD) is increasingly recognized in asthma, but less is known in patients using SABA-only therapy. We aimed to investigate the impact of SAD on asthma control in an unselected cohort of 60 adults with physician-diagnosed intermittent asthma treated with as-needed SABA monotherapy.
Methods |
All patients underwent standard spirometry and impulse oscillometry (IOS) at the first visit and were stratified by the presence of SAD defined by IOS (fall in resistance 5–20 Hz [R5-R20]>0.07 kPa × s*L−1). Univariable and multivariable analyses were used to analyze cross-sectional relationships between clinical variables and SAD.
Results |
SAD was present in 73% of the cohort. Compared with patients without SAD, adults with SAD had a higher number of severe exacerbations (65.9% versus 25.0%, p < 0.05), higher use of annual SABA canisters (median (IQR), 3 (1.75–3) versus 1 (1–2), p < 0.001), and significantly less well-controlled asthma (11.7% versus 75.0%, p < 0.001). Spirometry parameters were similar between patients with IOS-defined SAD and those without SAD. The multivariable logistic regression analysis showed that exercise-induced bronchoconstriction symptoms (EIB, odds ratio [OR] 31.18; 95%CI:4.85–365.00) and night awakenings due to asthma (OR 30.30; 95%CI:2.61–1141.00) were independent predictors of SAD, with a high predictive power of the model incorporating these baseline predictors (AUC 0.92).
Conclusions |
EIB and nocturnal symptoms are strong predictors of SAD in asthmatic patients using as-needed SABA-monotherapy, helping to distinguish subjects with SAD among patients with asthma when IOS cannot be performed.
Le texte complet de cet article est disponible en PDF.Highlights |
• | In community-treated patients with asthma treated with as needed SABA monotherapy, the prevalence of IOS-defined SAD was 73%. |
• | SAD associated with less well-controlled asthma, more severe asthma exacerbations and higher use of SABA in patients with intermittent asthma. |
• | FEF25-75% e R5-R20, spirometry and IOS parameters used to measure peripheral airway resistance did not correlate. |
• | Exercise-induced bronchoconstriction and nocturnal symptoms were independent predictors of SAD in patients with intermittent asthma. |
Keywords : Asthma, Impulse oscillometry, Small airways, Short-acting beta agonist
Abbreviations : SAD, FeNO, BMI, FEV1, FVC, FEF25-75, R5-R20, X5, Ax, FRes, ΔX5
Plan
Vol 209
Article 107154- avril 2023 Retour au numéroBienvenue sur EM-consulte, la référence des professionnels de santé.
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