Long-term efficacy beyond 10 years of subcutaneous immunotherapy for house-dust-mite–induced allergic rhinitis: A real-world evidence study

Background: This retrospective study evaluated real-world data on subcutaneous immunotherapy for house dust mites (HDM-SCIT) in children and adults with AR over aperiod exceeding 10 years. Aimed to observe the long-term efficacy of HDM-SCIT lasting more than 10 years in children and adults. Methods: Sixty-six patients, including 31 children and 35 adults who were allergic to house dust mite and received SCIT, were retrospectively analysed. All patients completed an immunotherapy course lasting 2–3 years. Questionnaire data were collected before and at the end of SCIT, and telephone follow-up was conducted to evaluate the long-term efficacy after 10 years. Results: Nasal and ocular symptoms in children and adults remained better controlled 10 years after the completion of HDM-SCIT (all p < 0.05). The efficacy for nasal and ocular symptoms in children persisted after 10 years (all p < 0.05), whereas the efficacy of other related symptoms declined (p = 0.414). The efficacy for nasal symptoms in adults remained stable (p = 0.888), whereas the efficacy for ocular symptoms and ear-itching symptoms declined (all p < 0.05). No statistically significant difference between children and adults (p = 0.607, p = 0.764). No adverse reactions persisted for 10 years or more. Conclusions:Up to 10 years after completing HDM-SCIT, both children and adults continued to exhibit significant improvement in their symptoms, while adults exhibited diminished nasal symptom benefit.The safety profile during treatment for both adults and children remained excellent even 10 years later.