Abstract
We have shown that asthmatic patients, despite being asymptomatic after 1-month treatment with inhaled corticosteroids (ICS), may have persistent sputum eosinophilia associated with higher degrees of bronchial hyperresponsiveness (Bacci et al., ATS meeting 2010). In order to test the effects of longer treatment periods, we treated 116 symptomatic, steroid-naive, mild-to-moderate asthmatic patients with different doses of ICS (50 to 500 mcg bid) for three to six months. Before and after treatment, all patients underwent spirometry, methacholine test, sputum analysis, and recorded symptom score (SS) and Peak Expiratory Flow (PEF) throughout the study period. Regardless of treatment dose and duration, some patients (n=56) still had high (≥ 2%) sputum eosinophils after ICS treatment; they were no different from patients with low sputum eosinophils as regards clinical and functional data after treatment, but had higher baseline SS (1.5 [0.1-3.6] vs 1.0 [0.1-3.1], p=0.04). After treatment, some patients still had high sputum eosinophils despite being totally controlled (SS=0); they were no different from totally controlled patients with low sputum eosinophils.
We conclude that, in patients with greater symptom levels before treatment, sputum eosinophilia may persist despite ICS treatment. Also, sputum eosinophilia may persist even in patients with totally controlled asthma, but after 6 months the relationship with bronchial hyperresponsiveness is lost, maybe because ICS also affect mechanisms involved in bronchial hyperresponsiveness other than sputum eosinophilia.
- © 2011 ERS