Prevalence of Exercise-induced Airway Narrowing in Schoolchildren from a Mediterranean Town

Abstract

A cross-sectional study was carried out on a random sample of 2,216 schoolchildren 9 to 14 yr of age to determine the prevalence of exercise-induced airway narrowing (EIAN) in a Mediterranean town (Mataró). A complementary case-control study measured the association between EIAN and respiratory symptoms. A free-running test was performed during school time. Peak expiratory flow rate (PEFR) was measured at rest and at 2, 5, 10, and 15 min after exercise. A total of 136 of 2,056 satisfactory runs showed a decrease of PEFR equal to or higher than 15% at each of these times after exercise. Five more children developed wheezing during running and were considered to have EIAN. Prevalence of EIAN was 6.9% (95% CI = 5.9 to 7.9). Prevalence decreased progressively with age. No sex difference was found. In the case-control study a questionnaire of respiratory symptoms was applied to the mothers of hyperresponsive children, as well as to two matched control subjects for each case. Questionnaire analysis showed a strong association between EIAN and respiratory symptoms or rhinitis. Association with bronchitis before 2 yr of age and parental asthma was less but significant.

Prevalence of asthma-related symptoms and bronchial responsiveness to exercise in children aged 13-14 yrs in Barcelona, Spain

“…The exclusion of these 25 has a small influence on the prevalence of bronchial responsiveness (11.4 versus 10.5%). Since reduction in PEFR due to fatigue was not studied by BARDAGÍ et al [15], it is not known whether differences in the prevalence of bronchial responsiveness after running between the present study and that of BARDAGÍ et al [15] may be attributed to the previously mentioned fatigue effect. In Zimbabwean children, the prevalence of exerciseinduced bronchoconstriction varied from 5.8% in an urban area with high living standards to 0.1% in a rural district [26].…”

“…In Zimbabwean children, the prevalence of exerciseinduced bronchoconstriction varied from 5.8% in an urban area with high living standards to 0.1% in a rural district [26]. Different prevalence rates in populations with a similar genetic background are illustrated by studies in Barcelona and Mataró [15]. In Zimbabwe, KEELEY et al [26] have also shown large differences in prevalence of reversible airway obstruction between populations living in close geographical proximities.…”

“…When planning this study, the protocol reported by BARDAGÍ et al [15] was followed and, consequently, the influence of methodological factors in the aforementioned differences should be small. In the present study, the high pollen season was exluded and, therefore, this factor cannot account for the reported difference.…”

“…The exercise test was performed outside under medical supervision (RMB). The method used was that reported by BARDAGÍ et al [15], based on guidelines developed by the American Academy of Allergy [18]. The peak expiratory flow rate (PEFR) was measured by means of a mini-Wright device (Clement Clark International, UK).…”

“…In Spain, a few studies have been carried out to determine the prevalence of asthma in childhood. Recently, BARDAGÍ et al [15] reported a prevalence of exercise-induced bronchoconstriction and/or clinical asthma of 4.1 and 3.2% in children aged 13 and 14 years, respectively.…”