[Prevalence of asthma in schoolchildren in Curitiba - ISAAC]

OBJECTIVE: To verify the prevalence of asthma in schoolchildren from Curitiba.METHOD: A written questionnaire of asthma symptoms (ISAAC-International Study of Asthma and Allergies in Childhood) was applied to children ages 6-7 years and adolescents 13-14 years registered in 32 public schools.RESULTS: 3,200 questionnaires were applied to 13-14 year-old adolescents, and 2,863 questionnaires to 6-7 year-old children. The questionnaire should be answered by the parents of 6-7 year-old children (group I) and by the adolescents themselves (13-14 year-old, group II). The rate of questionnaires returned was 58% for group I and 92% for group II. A presumptive diagnosis of asthma was based on having had 4 or more attacks of wheezing in the last 12 months, or 1-3 wheezing episodes in addition to night awakening for wheezing, nocturnal cough and wheezing after exercise. Under these criteria there were 15.7% asthmatics in group I and 11.6% in group II. Symptoms of rhinoconjunctivitis were found in 38% and 36%, and eczema in 11% and 10% for groups I and II, respectively. Among those with presumed asthma, over 70% denied having had asthma. The question "have you ever had asthma" although specific is not sensitive enough.CONCLUSION: The prevalence of asthma in Curitiba was 15.7% for children 6-7 years old and 11.6% for adolescents 13-14 years. The question "have you ever had asthma" did not contribute to defining cases with asthma.