Clinical Evaluation for Sublingual Immunotherapy With Dermatophagoides farinae in Polysensitized Allergic Asthma Patients

Background: Many studies have demonstrated the efficacy of single-allergen sublingual immunotherapy (SLIT) in polysensitized patients with allergic rhinitis (AR), but less is reported in polysensitized patients with allergic asthma (AS). Method: Data of 133 adult patients with house dust mite (HDM)-induced AS who had been treated for 3 years were collected. These patients were divided into the control group (treated with low to moderate dose of inhaled glucocorticoids and long-acting β2 agonists, n = 37) and the SLIT group (further treated with Dermatophagoides farinae drops, n = 96). The SLIT group contained three subgroups: the single-allergen group (only sensitized to HDM, n = 35), the 1- to 2-allergen group (HDM combined with one to two other allergens, n = 32), and the 3-or-more-allergen group (HDM combined with three or more other allergens, n = 29). The total asthma symptom score (TASS), total asthma medicine score (TAMS), and asthma control test (ACT) were assessed before treatment and at yearly visits. Forced expiratory volume in 1 s/forced vital capacity (FEV1/FVC) was assessed before treatment and at the end of SLIT. Results: TASS and ACT scores in the control group were significantly higher than that in the single-allergen group and the 1- to 2-allergen group after 1, 2, and 3 years of SLIT and significantly higher than that in the 3-or-more-allergen group after 3-year SLIT (all p < 0.05). TAMS of the control group was significantly higher than that of the other three groups after 0.5, 1, 2, and 3 years of SLIT (all p < 0.05). FEV1/FVC in the control group was significantly higher than baseline after 3 years of immunotherapy (p < 0.05). Conclusion: Patients sensitized to HDM with/without other allergens showed similar efficacy after 3 years of SLIT. However, the initial response of patients with three or more allergens was slower during immunotherapy process.