title: Spirometric tests to assess the prevalence of childhood asthma at Portuguese rural areas: influence of exposure to high ozone levels.
abstract: The study here reported aimed to: i) evaluate the prevalence of childhood asthma at a Portuguese rural area with high ozone concentrations through lung function tests, validating the previously estimated one assessed through questionnaires (similar to those of the ISAAC); ii) compare the achieved prevalence with the one reported at an unexposed area (with low ozone concentrations), aiming to evaluate the influence of exposure to high ozone levels; and iii) determine potential risk factors. Ninety-five of the original 478 children that completed the questionnaires, mentioned to have at least one of asthma symptoms (wheeze, dyspnea or cough) and were therefore evaluated by spirometry. FEV(1) was in average 89.7% for asthmatics and 102.8% for non-asthmatics. For the studied sample the risk was higher for girls with a tendency to be higher from 8 to 10 years old. Lifetime prevalence of childhood asthma at the exposed area was 9.2%. Children living at the exposed area had 3 times higher risk of having asthma than those living at the unexposed area. Considering that ozone concentrations were the main difference between both areas, it can be suggested that ozone pollution increased asthma prevalence. Nevertheless, it should be remarked that further studies should be done to confirm these results.
authors.affiliation: LEPAE, Departamento de Engenharia Química, Faculdade de Engenharia, Universidade do Porto, R. Dr. Roberto Frias, 4200-465, Porto, Portugal.
authors.forename: S I V
authors.initials: SI
authors.lastname: Sousa
authors.forename: C
authors.initials: C
authors.lastname: Ferraz
authors.forename: M C M
authors.initials: MC
authors.lastname: Alvim-Ferraz
authors.forename: F G
authors.initials: FG
authors.lastname: Martins
authors.forename: L G
authors.initials: LG
authors.lastname: Vaz
authors.forename: M C
authors.initials: MC
authors.lastname: Pereira
mesh_terms: D000293:Adolescent; D000393:Air Pollutants / Q000032:analysis*; D000397:Air Pollution / Q000706:statistics & numerical data*; D001249:Asthma / Q000175:diagnosis / Q000453:epidemiology*; D002648:Child; D003371:Cough / Q000453:epidemiology; D004417:Dyspnea / Q000453:epidemiology; D004784:Environmental Monitoring; D062665:Epidemiological Monitoring; D005260:Female; D006801:Humans; D019570:Inhalation Exposure / Q000032:analysis* / Q000706:statistics & numerical data; D008297:Male; D010126:Ozone / Q000032:analysis*; D011174:Portugal / Q000453:epidemiology; D012129:Respiratory Function Tests; D012135:Respiratory Sounds / Q000175:diagnosis; D012424:Rural Population / Q000706:statistics & numerical data; D013147:Spirometry; D011795:Surveys and Questionnaires
chemical_list: D000393:Air Pollutants; D010126:Ozone