title: Prevalence of asthma in children and adolescents in a city in the Brazilian Amazon region.
abstract: OBJECTIVE
  To analyze the prevalence of asthma and asthma symptoms in students of two distinct age brackets residing in the city of Tangará da Serra, Brazil.
  
  
  METHODS
  Cross-sectional, population-based study of the prevalence of asthma in children from 6 to 7 years of age and adolescents from 13 to 14, using the standardized International Study of Asthma and Allergies in Childhood, phase 1 questionnaire, validated for use in Brazil. Students who responded affirmatively to question 2 (presence of wheezing in the preceding 12 months) were classified as suffering from asthma.
  
  
  RESULTS
  The study comprised 3,362 students, of whom 1,634 (48.6%) were children and 1,728 (51.4%) were adolescents. Of the 1,634 children, 816 (49.9%) were male, and 818 (50.1%) were female. Of the 1,728 adolescents, 773 (45.0%) were male, and 955 (55.0%) were female. The prevalence of asthma among the children was 25.2%, whereas that among the adolescents was 15.9% (chi2 = 8.34; p = 0.00). The children presented higher prevalences of the following symptoms of asthma than did the adolescents: wheezing ever (54.3%), nocturnal dry cough (43.9%), wheezing in the preceding 12 months (25.2%), and from 1 to 3 attacks of wheezing in the preceding 12 months (19.1%). There were no differences between the two groups regarding physician-diagnosed asthma (approximately 4.5%). There were no statistical differences regarding the prevalence of asthma by gender in the two groups.
  
  
  CONCLUSIONS
  Tangará da Serra has a high prevalence of asthma in children and adolescents, and this result is compatible with other studies carried out in Brazil and Latin America using the same methodology.
authors.affiliation: Universidade do Estado de Mato Grosso, Cáceres, MT, Brazil. antonia-mr@unemat.br
authors.forename: Antonia Maria
authors.initials: AM
authors.lastname: Rosa
authors.forename: Eliane
authors.initials: E
authors.lastname: Ignotti
authors.forename: Sandra de Souza
authors.initials: Sde S
authors.lastname: Hacon
authors.forename: Hermano Albuquerque de
authors.initials: HA
authors.lastname: Castro
mesh_terms: D000293:Adolescent; D001249:Asthma / Q000175:diagnosis / Q000453:epidemiology*; D001938:Brazil / Q000453:epidemiology; D002648:Child; D004812:Epidemiologic Methods; D005260:Female; D006801:Humans; D008297:Male; D012135:Respiratory Sounds / Q000175:diagnosis