Prevalence of Asthma and Other Childhood Allergies in Brazilian Schoolchildren

Abstract

We determined the prevalence of asthma, rhinitis, and eczema among Brazilian children using the standardized protocol of the International Study on Asthma and Allergies in Childhood (ISAAC) to facilitate the comparison of our results with other studies using the ISAAC methodology. We conducted a cross-sectional study from June to October 1994 to determine the prevalence of asthma, rhinitis, and eczema in 5182 school children aged 7-8 years and 13-14 years residing in the Brazilian towns of Santa Maria and Itabira (iron-mining cities located in Minas Gerais). Parents completed questionnaires at their child's school in the presence of trained interviewers. The cumulative prevalence of doctor-diagnosed asthma was 4.6% for all ages with no significant difference between the age groups. In general, there was a higher prevalence of symptoms in the younger age group than the older. The prevalence of wheezing in the previous 12 months was 14.3% (7-8 years old) and 9.3% (13-14 years old) (p < 0.01), of chronic cough in the previous 12 months was 25.6% (7-8 years old) and 22.1% (13-14 years old) (p < 0.01), and of nighttime cough in the previous 12 months was 22.3% (7-8 years old) and 19.4% (13-14 years old) (p < 0.05). Overall the prevalences of asthma and wheezing symptoms in the previous 12 months were higher for boys than girls (5.2% vs. 3.9% for asthma, p < 0.01, and 13.2% vs. 10.6% for wheezing, p < 0.01, respectively). These results suggest that asthma-related respiratory illnesses affect a substantial part of the childhood population in Itabira and Santa Maria, Minas Gerais. Some factors such as male gender and younger age may be associated with an increase risk for chronic respiratory symptoms. Prevalences of asthma and allergic diseases in these Brazilian cities on the basis of self-reporting of symptoms and of one's medical history may more accurately portray the true prevalence of asthma than the use of medical records.

Prevalência e fatores de risco para asma em escolares de uma coorte no Sul do Brasil

“…By looking at the data separately, we may see that the prevalence ranged from 4.8% in Itabira to 21.9% in Porto Alegre, in those individuals aged 13-14 years. [4][5][6][7] A cross-sectional study done with schoolchildren in Rio de Janeiro showed a prevalence of 21.7% for asthma according to the criteria of the questionnaire used (modified ATS-DLD-78 C). 8 Childhood asthma is a multicausal disease that has been associated with genetic, environmental, gestational and socioeconomic factors, among others, in several studies with children and adolescents.…”

Asma em escolares do Recife - comparação de prevalências: 1994-95 e 2002

“…In Itabira and Santa Maria, cities in Minas Gerais state, a reported prevalence of asthma of 4.6% was observed in schoolchildren. 12 Chatkin,8 found a prevalence of 25.4% in a cohort from the city of Pelotas in 1997-98.…”

Asthma in schoolchildren from Recife, Brazil. Prevalence comparison: 1994-95 and 2002

“…¦ Excluindo-se os não respondidos: prevalência = 19,7% (IC de 95%: 18,3-21,1%). ¶ Excluindo-se os não respondidos: prevalência = 19,4% (IC de 95%: 17,[9][10][11][12][13][14][15][16][17][18][19][20]9). ** Considerando-se o total dos dois períodos e excluindo-se os não respondentes: χ 2 de Pearson, p < 0,001.…”

“…Camargos et al 11 , estudando adolescentes de 13 e 14 anos no interior de Minas Gerais, encontraram uma prevalência cumulativa de 27% de asma referida. Em Itabira e Santa Maria, cidades mineiras, observou-se uma prevalência de asma referida de 4,6% em escolares 12 . Em uma coorte na cidade de Pelotas, em 1997-98, Chatkin 8 encontrou uma prevalência de 25,4%.…”