Effects of Aeroallergen Sensitization on Symptom Severity, Pulmonary Function, and Bronchodilator Response in Children With Bronchial Asthma

Abstract

Background: Allergen sensitization, symptom severity, pulmonary function test, and bronchodilator response are important in the diagnosis and treatment of asthma. However, the relationship between these factors remains unclear. Objective: The objective of this study was to investigate the relationship between aeroallergen sensitization and asthma severity, pulmonary function, and bronchodilator response among pediatric patients with bronchial asthma. Methods: This was a prospective study where 155 pediatric patients aged 7–18 years old with bronchial asthma were recruited from Outpatient Clinics. Patients who met the inclusion criteria proceeded with spirometry and aeroallergen skin prick test. Results: There was a significant degree of sensitization, wherein 100% of the patients had sensitization to one or more aeroallergens. Among these children, 106 (68%) were polysensitized. The polysensitized group had more severe and persistent asthma severity profile (p<0.001) and worse pulmonary function (p<0.001). The frequency of abnormal pre-bronchodilator lung function of the polysensitized group was higher than the monosensitized group (p<0.001). A positive bronchodilator response was higher among polysensitized children as compared to monosensitized children (p<0.001). Sensitization to Dermatophagoides farinae, Dermatophagoides pteronyssinus and dog correlated with impairment of both the large airways and distal small airways while sensitization to cat, cockroach, and horse correlated only with impairment of the large airways (p<0.05). Patients sensitized to D. farinae, D. pteronyssinus, cat and dog had significant bronchodilator response (p<0.05). Conclusion: Polysensitized asthmatic children had a more persistent and severe asthma profile, worse pulmonary function, and higher bronchodilator reversibility compared to the monosensitized group.