Background: Allergen sensitization and airway hyperresponsiveness (AHR) are the most important characteristics of bronchial asthma and their correlation has been speculated.
Objective: We attempted to investigate the relationship between sensitization to allergens and AHR to methacholine in Korean high school students.
Methods: A questionnaire survey, methacholine bronchial provocation tests, and skin-prick tests for 16 major allergens were performed on 724 students. The mean age of participants was 15.79 ± 0.40 years old. Serum total immunoglobulin E (IgE) and the fraction of blood eosinophils were measured.
Results: AHR (PC(20) < 16 mg/ml) was present in 12.3%. Log total IgE was higher in AHR-positive group than negative group (4.22 ± 1.55, 3.70 ± 1.33, P = 0.001). Three hundred eighty-four students (53.0%) were sensitized to more than one allergen, and among them Dermatophagoides pteronyssinus (Der p, 295 students, 40.7%) and Dermatophagoides farinae (Der f, 301 students, 41.6%) were most common. The risk of AHR development was high in the group who had sensitization to one allergen (adjusted odds ratio [aOR] = 1.97, 95% confidence interval [CI]: 1.13-3.44, P = 0.018) and to more than two allergens (aOR = 2.94, 95% CI: 1.32-6.57, P = 0.009). Among the specific allergens, AHR was developed in those who were sensitized to Der f (aOR = 1.73, 95% CI: 1.04-2.86, P = 0.033), dog dander (aOR = 3.97, 95% CI: 1.67-9.51, P = 0.002), and Alternaria (aOR = 3.19, 95% CI: 1.24-6.41, P = 0.016). In the groups with high IgE (>300 IU/ml) and high eosinophil fraction (>4%), AHR was more developed than groups who were low in each (aOR = 2.73, 95% CI: 1.15-6.51, P = 0.023; aOR = 10.82, 95% CI: 3.33-35.08, P = 0.001).
Conclusion: The risk of AHR development was closely linked with allergen sensitization itself, and the number or types of sensitized allergens such as indoor and fungal allergens in Korean young adolescents.