Asthma and allergic rhinitis in Quebec children
BACKGROUND: The Health and Social Survey of Quebec Children and Youth, conducted on representative samples of children nine, 13 and 16 years of age, provided data on the prevalence and determinants of asthma and allergic rhinitis in Quebec. OBJECTIVES: To determine the prevalence of asthma and allergic rhinitis among children in the province of Quebec and to identify the determinants of these pathologies. METHODS: Three groups of more than 1100 children aged nine, 13 and 16 years were recruited. Respiratory symptoms were documented using the International Study of Asthma and Allergies in Childhood questionnaire. Questions enquiring about family income, smoking, degree of urbanization of the child's school's location and various variables related to indoor air were also included. The comparisons of proportions were done using the chi2 test. RESULTS: The prevalence rates for reported history of asthma varied from 14% to 15% depending on the age group. The prevalence of wheezing in the past year was 7% to 8%. Asthma was the primary cause of the limitation of activities due to a health problem in nine- and 13-year-old Quebecers, and the second most common cause in 16-year-old Quebecers. The prevalence of rhinitis, rhinoconjunctivitis and reported history of hay fever increased with age, reaching 28.0%, 15.9% and 21.1%, respectively, in the 16-year-old group. The prevalence of asthma and wheezing was associated with family history and allergies, and inversely related to family income. CONCLUSIONS: The prevalence of childhood asthma is high in the province of Quebec. It is a major cause of the limitation of activities due to a health problem for young Quebecers. A family history of asthma and an atopic predisposition are important determinants in the development of asthma in Quebec.