Background: Few studies have compared the effects of immunotherapy and inhaled steroids. The main limitation of such studies is the long duration required to fully appreciate the effects of immunotherapy.
Objective: To compare the effects of inhaled budesonide and sublingual immunotherapy (SLIT) in mild persistent asthma for up to 5 years.
Methods: Patients with mild persistent asthma and rhinitis due to grass pollen were enrolled in an open randomized controlled trial. After a run-in season, they were randomized to either budesonide, 800 microg/d, in the pollen season or continuous grass SLIT for 5 years. All patients received rescue medications. Symptoms were evaluated by diary cards filled out from May to July at baseline and after 3 and 5 years. In-season nasal eosinophils and bronchial hyperresponsiveness were also assessed.
Results: Fifty-one patients were enrolled and 46 completed the study. The bronchial symptom scores and the use of bronchodilators decreased significantly in both groups, but the improvement was greater in the SLIT patients at 3 and 5 years. The nasal symptom score and the intake of nasal steroids decreased only in the SLIT group, and the difference vs the budesonide group was always significant. In the SLIT group vs the budesonide group, a statistically significant decrease of nasal eosinophils was found at 3 and 5 years (P < .01). The bronchial hyperresponsiveness improved significantly only in the SLIT group.
Conclusion: In patients with grass pollen-induced asthma, in the long term SLIT was equally effective as inhaled budesonide in treating bronchial symptoms and provided an additional benefit in treating rhinitis symptoms and bronchial hyperresponsiveness.