EUROPEAN STUDY ON ASTHMA - THE PREVALENCE OF BRONCHIAL HYPERREACTIVITY AND ASTHMA IN YOUNG-ADULTS IN 5 SPANISH REGIONS

BACKGROUND: The European Study on Asthma is a multicentric survey desi gned to determine variations in the prevalence of asthma and its deter minants in Europe. The first phase of the study in Spain, by means of a short questionnaire, allowed to estimate the prevalence of symptoms related to asthma in representative samples of five Spanish areas: Alb acete, Barcelona, Galdakao, Huelva and Oviedo. MATERIAL AND METHODS: T he annual prevalence of symptoms related to asthma was determined with a respiratory questionnaire adapted from the IUATLD questionnaire. Pa rticipants performed a forced spirometry and bronchial hyperresponsive ness was measured through a methacholine challenge. A hyperreactive in dividual was defined as a subject with a fall in FEV(1) of 20% or more during the challenge (cumulative dose of inhaled methacholine of 5.11 7 mu mol) or extrapolating tb 8 mu mol. RESULTS: The prevalence of bro nchial hyperresponsiveness ranged from 8.3% in Galdakao (95% CI 5.5-11 .2) to 31.7% in Albacete (95% CI 28.6-36.6). The prevalence of asthma, defined as presence of bronchial hyperresponsiveness and symptoms rel ated to asthma was: 4.7% in Albacete (95% CI 2.4-6.9); 3.5% in Barcelo na (95% CI 0.7-6.2); 1.1% in Galdakao (95% CI 0.0-2.2); 1.0 in Huelva (95% CI 0.0-2.2); and 1.7 in Oviedo (95% CI 0.0-3.3). Different defini tions of asthma produced variations of 3.1 to 4.7 fold in the prevalen ce of asthma between the five participating areas. CONCLUSIONS: Asthma is a common disorder in Spain and there are substantial variations in the prevalence of bronchial hyperresponsiveness and asthma between th e five Spanish areas surveyed.