Efficacy of add-on sublingual immunotherapy for adults with asthma A meta-analysis and systematic review

Background: Sublingual immunotherapy (SLIT) reduces symptom scores and the use of rescue medication in children with allergic asthma, but the effect of SLIT therapy in adult patients has not been reported. Objective: To examine the efficacy and adverse effects of SLIT add-on vs conventional medication in adult patients with mild to moderate asthma. Methods: We systematically searched the MEDLINE, Embase, Cochrane, and Central databases. Eligible studies included adult patients with allergic asthma who received either SLIT or standard care. Standard mean differences were used as measures of efficacy in a random-effects model. Results: Twenty trials that included 2,288 patients in the SLIT add-on group and 1,268 patients in the traditional therapy group were identified as eligible for final analysis. Compared with traditional therapy, SLIT add-on therapy was associated with significant improvements in lower and upper airway scores, a higher forced expiratory volume in 1 second, and maximal expiratory flow at 25% of forced vital capacity, and improved bronchial reactivity. Drug consumptions were significantly decreased as well. Airway inflammatory parameters, such as nasal eosinophil infiltration, were markedly improved. Conclusion: The findings of this study suggested that long-term SLIT add-on therapy is a complementary treatment for adults with asthma in addition to conventional medicine. It not only reduces symptom scores but also improves lung function and airway inflammation. (C) 2018 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.