Objective: To investigate impact factors for the efficacy of specific immunotherapy (SIT) in children with dust mite allergic asthma.
Methods: Ninety-nine children with house dust mite allergic asthma received standardized SIT, and the level of asthma control was evaluated after 6 months (S1 stage), 12 months (S2 stage), 18 months (S3 stage), and 24 months (S4 stage) of treatment. The age of first visit, course of asthma, level of asthma severity, initial serum specific immunoglobulin E (sIgE) level, combination with allergic rhinitis or atopic dermatitis, use of inhaled corticosteroids, and local or systemic side effects during treatment were recorded, and their impacts on the level of asthma control were analyzed.
Results: As the SIT proceeded, the number of clinically controlled cases increased significantly (P<0.01). The level of asthma control was significantly affected by the age of patients at first visit in S1 and S3 stages, and combination with allergic rhinitis or atopic dermatitis in S1 stage (P<0.05). In all stages of SIT, the controlled cases had significantly higher initial serum sIgE levels than the uncontrolled cases (P<0.05). In S1 and S2 stages, there was a significantly higher proportion of controlled cases among children with a high level of asthma severity than among those with a low level of asthma severity (P<0.05).
Conclusions: There is a positive correlation between long-term efficacy of SIT and the course or the total dose of treatment. Patients with higher initial serum sIgE levels achieve clinical control earlier than those with lower initial serum sIgE levels during SIT.