Asthma and other atopic diseases in Australian children. Australian arm of the International Study of Asthma and Allergy in Childhood

Abstract

OBJECTIVE: To determine the prevalence of asthma, eczema and allergic rhinitis in Australian schoolchildren using the protocol of the International Study of Asthma and Allergy in Childhood (ISAAC). DESIGN: Questionnaire-based survey. SETTING: Melbourne, Sydney, Adelaide (in winter-spring, 1993) and Perth (in winter-spring, 1994). SUBJECTS: All children in school years 1 and 2 (ages 6-7 years) or in year 8 (ages 13-14 years), attending a random sample of 272 schools, stratified by age and city. MAIN OUTCOME MEASURES: Parent-reported (for 6-7 year olds) or self-reported (for 13-14 year olds) symptoms of atopic disease in the previous 12 months, or ever; treatment of asthma; and country of birth. RESULTS: 10 914 questionnaires were completed for 6-7 year olds and 12 280 for 13-14 year olds (84% and 94% response rates, respectively). Prevalence of wheeze in the past 12 months was 24.6% for the 6-7 year olds and 29.4% for the 13-14 year olds, and, among 6-7 year olds, was significantly higher in boys (27.4%) than girls (21.7%). Children born in Australia were more likely to report current wheeze than those born elsewhere (6-7 year olds: odds ratio [OR], 1.82; 95% confidence interval [CI], 1.55-2.15; and 13-14 year olds: OR, 1.88; 95% CI, 1.68-2.11). Prevalences of current eczema and allergic rhinitis were 10.9% and 12.0%, respectively, for the 6-7 year olds, and 9.7% and 19.6%, respectively, for the 13-14 year olds. Asthma, eczema and rhinitis coexisted in 1.8% of 6-7 year olds and 2.8% of 13-14 year olds. CONCLUSION: This study provides evidence that asthma prevalence in Australian schoolchildren is continuing to increase and is higher among Australian-born children than among those born elsewhere. Asthma, eczema and allergic rhinitis coexist to a lesser extent than expected. These results form the basis for future Australian and international comparisons.