Changes in the Prevalence of Childhood Asthma in Seoul from 1995 to 2008 and Its Risk Factors

Purpose: To investigate the prevalence of asthma and determine its risk factors in elementary school students in Seoul. Methods: A modified International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire was used to survey 4,731 elementary school students from five areas in Seoul between April and October, 2008. Results: In elementary school children, the lifetime and recent 12-month prevalence of wheezing were 11.7% and 5.6%, respectively. The lifetime prevalence of asthma diagnosis was 7.9%, and the recent 12-month prevalence of asthma treatment was 2.7%. Male sex (adjusted odds ratio (aOR], 1.90; 95% confidence interval [Cl], 1.36-2.66), history of atopic dermatitis (AD) (aOR, 2.76; 95% Cl, 1.98-3.84), history of allergic rhinitis (AR) (aOR, 3.71; 95% CI, 2.61-5.26), history of bronchiolitis before 2 years of age (aOR, 2.06; 95% CI, 1.39-3.07), use of antibiotics during infancy for >3 days (aOR, 1.88; 95% CI, 1.35-2.62), parental history of asthma (aOR, 2.83; 95% CI, 1.52-5.27), exposure to household molds during infancy (aOR, 1.84; 95% CI, 1.18-2.89), and the development or aggravation of asthma symptoms within 6 months after moving to a new house (aOR, 11.76; 95% CI, 5.35-25.86) were the independent risk factors for wheezing within 12 months. Conclusions: The prevalence of wheezing and asthma in elementary school students in 2008 was similar to that in the past decade. Male sex, history of AD, history of AR, history of bronchiolitis before 2 years of age, parental asthma, use of antibiotics during infancy, exposure to molds in the house during infarcy, and development or aggravation of asthma symptoms within 6 months after moving to a new house, could be risk factors for wheezing within 12 months.