title: Acute effects of Asian dust events on respiratory symptoms and peak expiratory flow in children with mild asthma.
abstract: The aim of this study was to investigate the possible adverse effects of Asian dust events on respiratory health in asthmatic children. Fifty-two children with mild asthma were studied for eight consecutive weeks in the spring of 2004 (March 8 to May 2). During the study period, five Asian dust days were identified; we included a lag period of two days following each of the events. Subjects recorded their respiratory symptom diaries and peak expiratory flow (PEF) twice daily during the study period; and they underwent methacholine bronchial challenge tests. The subjects reported a significantly higher frequency of respiratory symptoms during the Asian dust days than during the control days. They showed significantly more reduced morning and evening PEF values, and more increased PEF variability (10.1%+/-3.5% vs. 5.5%+/-2.2%) during the Asian dust days than during the control days. Methacholine PC(20) was not significantly different between before and after the study period (geometric mean: 2.82 mg/mL vs. 3.16 mg/mL). These results suggest that the short-term Asian dust events might be associated with increased acute respiratory symptoms and changes in PEF outcomes. However, there might be little long-term influence on airway hyperresponsiveness in children with mild asthma.
authors.affiliation: Department of Pediatrics, Korea University Anam Hospital, Seoul, Korea.
authors.forename: Young
authors.initials: Y
authors.lastname: Yoo
authors.forename: Ji Tae
authors.initials: JT
authors.lastname: Choung
authors.forename: Jinho
authors.initials: J
authors.lastname: Yu
authors.forename: Do Kyun
authors.initials: DK
authors.lastname: Kim
authors.forename: Young Yull
authors.initials: YY
authors.lastname: Koh
mesh_terms: D000293:Adolescent; D001249:Asthma / Q000503:physiopathology*; D016535:Bronchial Hyperreactivity / Q000503:physiopathology; D002648:Child; D004391:Dust; D005260:Female; D006801:Humans; D008297:Male; D016210:Methacholine Chloride; D010366:Peak Expiratory Flow Rate; D012120:Respiration Disorders / Q000209:etiology* / Q000503:physiopathology
chemical_list: D004391:Dust; D016210:Methacholine Chloride