Prevalence of Asthma and Related Symptoms in School-Age Children in São Paulo, Brazil—International Study of Asthma and Allergies in Children (ISAAC)

Abstract

We studied the prevalence of asthma and related symptoms using a standard written questionnaire designed for the International Study of Asthma and Allergies in Children (ISAAC). The written questionnaire (questions 1-8 related to asthma) was applied to 3005 children aged 6-7 years and to 3008 children aged 13-14 years. The parents of the 6-7-year-old children answered the questionnaire, whereas the 13-14-year-old children answered the questionnaire themselves. Response rates were 72% in the 6-7-year-old group and 94% in the 13-14-year-old group. There was a slight predominance of females in the population studied (male:female ratio 0.94). In the group of the 6-7-year-old children, the prevalence of diagnosed asthma was 7.3% for boys and 4.9% for girls, and in the group of the 13-14-year-old children, the prevalence was 9.8% and 10.2% for boys and girls, respectively. Asthma severity was similar for both age groups, and wheezing following exercise was more frequent among the adolescents. In keeping with studies in other parts of the world, comparison between reported symptoms and diagnosed asthma revealed significantly lower frequency of diagnosed asthma, suggesting that in the population we have studied, asthma is underdiagnosed. Using a global cut-off score to define asthma, we found a significantly higher prevalence of asthma among 6-7-year-old boys, as compared to girls (23.8% vs. 20.4%), and no significant differences among adolescent boys and girls (22.5% and 21.9%, respectively).

Prevalência de rinite alérgica em adolescentes do Distrito Federal: comparação entre as fases I e III do ISAAC

“…We believe that underdiagnosis is the cause of the predominance of current rhinitis, as has been mentioned in the case of asthma. 17,18 We observed a predominance of females among the children with rhinitis, which is in agreement with other publications. 19,20 The seasonal variation of allergic rhinitis with increased prevalence during the winter has also been reported.…”

Fatores de risco para consultas em pronto-socorro por crianças asmáticas no Sul do Brasil

“…1 Foi utilizado o ponto de corte de 5 pontos nas perguntas sobre sinais e sintomas para o diagnóstico de asma, com base no estudo de Solé. 12 Nas perguntas, foi utilizado o termo "bronquite" juntamente com "asma" devido à sua ampla utilização na população estudada.…”

Asma e fatores associados em adolescentes de 13 e 14 anos em São Luís, Maranhão, Brasil

“…Os estudos epidemiológicos devem ser realizados com questões padronizadas, avaliação de gravidade e medidas objetivas, conduzidos em mais de uma ocasião em todo o mundo para, de forma mais confiável, acompanhar a tendência mundial da prevalência de asma e detectar variações em diferentes regiões geográficas 9,10 .…”