Effects of corticosteroids on lung function in asthma and chronic obstructive pulmonary disease.

Both oral and inhaled corticosteroids have clinically significant effects on symptoms, exacerbations, health status, and lung function in asthma, and to a lesser extent in chronic obstructive pulmonary disease (COPD). Change in FEV(1) does not correlate well with functional tests in COPD and may not be the best measure of response to treatment. Inhaled corticosteroids may be beneficial when added to a beta-agonist for treatment of acute asthma, and the efficacy of oral corticosteroids in this setting is well established. Oral corticosteroids inconsistently improve lung function in stable outpatients with COPD. Individual inhaled corticosteroids do not have a marked effect, but the combination of fluticasone propionate and salmeterol and the combination of budesonide plus formoterol seem to improve FEV(1) over treatment with the individual components. In addition, there is convincing evidence for the use of systemic corticosteroids during acute exacerbations of COPD. Some evidence suggests that patients with COPD who respond to corticosteroids have eosinophilic inflammation and other attributes of an asthma phenotype.