Enhancing quality of life with 3-year course of sublingual immunotherapy for house dust mite-induced allergic rhinitis: An observational prospective study in real-life settings

Purpose

This prospective study aims to provide further supportive evidence by assessing the sustained effectiveness and safety of sublingual immunotherapy (SLIT) using a vaccine containing house dust mite (HDM) extracts in patients diagnosed with allergic rhinitis (AR) with/without conjunctivitis (AR/C).

Materials and methods

AR/C patients (n = 111, SLIT group: 57, control group: 54) allergic to HDM were treated with standardized SLIT drops or symptomatic drugs from October to December in 2020. The patients were directed by the investigators to attend annual hospital visits for the assessment of various parameters including the Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ), visual analog scale (VAS), total nasal symptom score (TNSS), total ocular symptom score (TOSS) and total medication score (TMS). During the study period, all participants were mandated to maintain comprehensive records of any adverse events (AEs) on diary cards, which were then communicated to the investigators via telephone.

Results

At baseline (2020), TNSS, TOSS, TMS, VAS, and RQLQ scores were comparable between SLIT and control groups (P > 0.05). After one year of treatment (2021), significant reduction in all scores compared to the baseline for both groups (P < 0.001). At the end of the second year of treatment (2022), TNSS and RQLQ score in the SLIT group continued to decrease significantly compared to 2021 (P < 0.05). In the third year (2023), the control group showed a rebound in TNSS, TOSS, TMS, and RQLQ scores, significant differences compared to 2022 or 2021 (P < 0.05). Besides, the SLIT group had significantly lower scores across all domains of RQLQ compared to the control group (P < 0.001). Symptomatic treatment influenced the scores of Nasal Symptoms, Eye Symptoms, Practical Problems, and Emotions domains significantly in 2023 compared to 2021 or 2022 (P < 0.05). Within the SLIT group, no significant differences in TNSS, TMS, VAS, and RQLQ scores were observed between monosensitized and polysensitized patients throughout the three years of treatment (P > 0.05). All AEs were mild to moderate.

Conclusion

The 3-year course of HDM-SLIT has shown significant therapeutic efficacy and a favorable safety profile in patients with AR/C. Importantly, our study presents initial evidence suggesting that the greater impact of AR/C on quality of life (QoL) may primarily stem from nasal symptoms, eye symptoms, practical issues, and emotional well-being.