Abstract
Systemic corticosteroids are known to cause skeletal muscle dysfunction but their impact on respiratory muscles is less clear. To investigate the effect of corticosteroids on respiratory muscles, their function was non-invasively assessed in healthy individuals and asthma patients using inhaled corticosteroids either alone or with add-on systemic corticosteroids.
The maximal expiratory pressure was significantly lower (PImax, p < 0.05) and tension-time index significantly higher (TT0,1, p < 0.0001) in patients with steroid-dependent asthma compared with both healthy individuals and asthma patients treated with inhaled corticosteroids alone. Systemic corticosteroids seem to have caused clinically significant respiratory muscle dysfunction in the patient sample.