Prevalence of childhood allergic diseases in central Taiwan over the past 15 years.

BACKGROUND The prevalence of asthma, allergic rhinitis and atopic eczema in children from the developed and developing countries has been increasing. METHODS Three epidemiological surveys of the prevalence of bronchial asthma, allergic rhinitis and atopic eczema in schoolchildren in Taichung, located in central Taiwan, were conducted in 1987, 1994, and 2002. The first questionnaire was used before the International Study of Asthma and Allergies in Childhood (ISAAC) written questionnaire was developed; the last two surveys were modified using ISAAC questionnaires. RESULTS A total of 37,801, 75,960, and 11,580 children were studied in 1987, 1994 and 2002, respectively. The prevalence of allergic diseases had increased in the past two decades. Results indicate that the prevalence of bronchial asthma had risen, from 2.19% in 1987, and 3.54% in 1994, to 6.99% in 2002. Regardless of sex, the prevalence of bronchial asthma decreased with increasing age. The prevalence of allergic rhinitis was 5.1% in 1987, 12.46% in 1987, and 27.59% in 2002, and the prevalence of atopic eczema was 1.10% in 1987, 1.88% in 1994, and 3.35% in 2002. CONCLUSION There has been a significant increase in the prevalence of bronchial asthma, allergic rhinitis and atopic dermatitis in Taichung schoolchildren from 1987 to 2002.