Background: The prevalence of asthma and allergic diseases in children has increased worldwide.
Objective: To perform the phase 3 survey of the International Study of Asthma and Allergies in Children (ISAAC) to report the time trend of the prevalence and severity of asthma and allergic diseases in children in Taipei.
Methods: Two junior high schools in each of the 12 school districts in Taipei were randomly chosen to enter the study. All students aged 13 to 14 years in the chosen schools were invited to participate in written and video questionnaires in Chinese (identical to those of the ISAAC phase 1 survey). The study was performed between December 1, 2001, and January 31, 2002. All data analysis followed the protocol of the ISAAC and then was submitted to the ISAAC International Data Center.
Results: Of 6653 eligible children from 23 high schools (1 school refused participation), 6381 (95.9%) participated. The prevalence of symptoms of asthma, allergic rhinitis, and atopic eczema in the past 12 months in 13- to 14-year-old children increased by 37%, 51%, and 193%, respectively, on written questionnaires during a 7-year period. The severity of asthma symptoms, including more than 4 wheezing attacks in the past 12 months, wheezing that disturbs sleep more than once per week, and wheezing that limited speech in the past 12 months, did not show any significant changes on written questionnaires during the 7 years.
Conclusion: The increasing prevalence of symptoms of asthma, allergic rhinitis, and atopic eczema in 13- to 14-year-old children in Taipei in a 7-year period is a significant burden on public health systems in Taiwan.