Four Different Phenotypes of Bhr Changing Pattern in School Children and It's Risk Factors
Sunday, March 6, 2016
South Exhibit Hall H (Convention Center)
Young-Ho Kim, MD, Eun Lee, Song-I Yang, Hyun-Ju Cho, MD, Hyung-Young Kim, Ji-Won Kwon, MD, Young Ho Jung, MD, Byoung-Ju Kim, Ju-Hee Seo, MD, Hyo-Bin Kim, MD, PhD, So-Yeon Lee, Ho-Jang Kwon, MD PhD, Soo-Jong Hong, MD, PhD
Rationale: Bronchial hyperresponsiveness (BHR) is a key feature of asthma, but the natural course is heterogenous.

Methods: Total 1,245 elementary school children were included from the CHEER study. ISSAC questionnaire, total IgE, blood eosinophil (%), skin prick test, pulmonary function test, and methacholine challenge test were done at age 6-8 years for baseline and follow up at age 10-12 years. We divided the BHR changing pattern into 4 pheynotypes. Multinomial logistic regression analysis was done to evaluate the risk factors for each phenotype.

Results: 4 phenotypes of BHR were composed of BHR never (897), BHR remission (197), BHR new (81), and BHR persistent (70) respectively. BHR persistent showed high eosinophil, high logIgE, and low lung function than other groups. Atopic sensitization (aOR=4.329, 95% CI 2.056-9.115), especially Dp and Df sensitization (aOR=2.986, 95% CI 1.475-6.044, aOR=3.284, 95% CI 1.627-6.627) were the risk factors for BHR persistent at age 6-8 years. Newly sensitization of Dp and Df at 10-12 years were associated with BHR new later (aOR=2.258, 95% CI 1.206-4.225, aOR=2.657, 95% CI 1.394-5.065). The mean Dp and Df wheal size of BHR persistent were bigger than other groups (P value < 0.05), but later at 10-12 years, there were no differences between BHR persisten and BHR new. Eosinophil (%) and logIgE of BHR persistent were higher than other groups at all age.

Conclusions: Atopic sensitization with Dp and Df was the most important risk factor for BHR persistent and was associated with later development of BHR. These findings suggest that high and new allergen sensitization is linked to persistent BHR and new development of BHR.