PREVALENCE OF ASTHMA-RELATED SYMPTOMS AND BRONCHIAL RESPONSIVENESS TOEXERCISE IN CHILDREN AGED 13-14 YEARS IN BARCELONA, SPAIN

It is not clear whether asymptomatic bronchial responsiveness is a ris k factor for development of asthma, A cross-sectional study was conduc ted to determine the prevalence of asthma among schoolchildren from Ba rcelona (Spain). The association between respiratory symptoms and bron chial responsiveness to exercise was examined. For this study 3,033 sc hoolchildren aged 13-14 yrs were studied from the general population, Participants answered a respiratory questionnaire and a self-reporting video-questionnaire, A total of 2,842 children underwent bronchial re sponsiveness testing by exercise challenge. The study was part of the International Study of Asthma and Allergies in Childhood (ISAAC) proje ct. The prevalence of ''current asthma'' (recent wheezing and bronchia l responsiveness to exercise) was 4% and the prevalence of ''wheezing only'' 10%, A fall in peak expiratory flow rate (PEFR) greater than or equal to 15% after exercise testing was found in 324 (11%) children, 29 (9%) of whom presented clinical symptoms of asthma, Bronchial respo nsiveness to exercise was significantly associated with all items of t he asthma questionnaire, The prevalence of asthma-related symptoms in this inner-city area was lower than frequently reported rates in other countries, although the prevalence of exercise-induced bronchoconstri ction was relatively high, and threefold greater than in a geographica l area in the vicinity of Barcelona. These findings are consistent wit h the current view that asthma-related symptoms and bronchial responsi veness to exercise have different meanings in a community survey, and that local environmental factors could influence the prevalence of bro nchial responsiveness.