Correspondence: “The effectiveness of pollen allergen immunotherapy on allergic rhinitis over 18 years: A national cohort study in Denmark”

Abstract

To the Editor, We read with interest the publication by Bager et al. 1 The literature on long-term effectiveness in allergen immunotherapy (AIT) remains limited. The findings from Bager et al. 1 hold promise in broadening our knowledge in this area by employing a large national cohort. We acknowledge the inherent challenges associated with conducting registry studies within respiratory allergies using Danish registries, which lead to structural limitations that warrant specialist consideration during study design. In the REACT study by Fritzsching et al., 2 which applied rigorous Data sharing not applicable to this article as no datasets were generated or analysed during the current study.