title: Spirometric airflow obstruction in Bangkok school children: prevalence and risk factors.
abstract: OBJECTIVE
  Determine the prevalence of airflow obstruction in schoolchildren in Bangkok and identify its risk factors.
  
  
  METHODS
  Schoolchildren, aged 6 to 18 years, were randomly selected from six schools in central Bangkok. Parents of the children completed a questionnaire. Standard spirometry was performed Children were classified as having airflow obstruction if FEV/FVC ratio was < 0.8. Children with FEV1/FVC ratio > or = 0.8, matched by sex, age, weight, and height, were randomly selected and classified as having no airflow obstruction. Risk factors were identified by univariate and multivariate analyses.
  
  
  RESULTS
  Among 1,065 children assessed by spirometry, 43 (4%) demonstrated airflow obstruction. Only three factors including wheezing apart from cold in the past 12 months (OR, 12.82; 95% CI, 1.3-126.5), family history of allergic rhinitis (OR, 2.54; 95% CI, 1.21-5.32), and starting infant formula since birth (OR, 2.47; 95% CI, 1.21-5.04) were shown to be significant risk factors associated with airflow obstruction.
  
  
  CONCLUSIONS
  The prevalence of airflow obstruction in schoolchildren is lower than those reported in most adult studies. Asthma and family history of allergic rhinitis are important risk factors associated with airflow obstruction. Exclusively breastfeeding since birth might be another helpful measure to prevent the development of airflow obstruction in children.
authors.affiliation: Department of Pediatrics, Lerdsin General Hospital, Bangkok, Thailand. supitra@hotmail.com
authors.forename: Supitra
authors.initials: S
authors.lastname: Suwanpromma
authors.forename: Charoon
authors.initials: C
authors.lastname: Boonlarbtaweechoke
authors.forename: Umaporn
authors.initials: U
authors.lastname: Udomsubpayakul
authors.forename: Arunwan
authors.initials: A
authors.lastname: Preutthipan
mesh_terms: D000293:Adolescent; D000402:Airway Obstruction / Q000453:epidemiology* / Q000503:physiopathology*; D016009:Chi-Square Distribution; D002648:Child; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D015995:Prevalence; D012307:Risk Factors; D013147:Spirometry; D011795:Surveys and Questionnaires; D013785:Thailand / Q000453:epidemiology; D014505:Urban Population