the prevalence of asthma among the students (7-18 years old) in tehran during 2002-2003

asthma is one of the most common problems of childhood, responsible for a significant proportion of abstinence from school because of chronic illness. this study was carried out among the school-aged children (7-18 years) in tehran schools during 2002-2003, in order to determine the frequency of asthma. according to the recommendation of who (world health organization), we designed a questionnaire, containing 8 standard questions, and the students were given necessary information to complete the questionnaires. the pre-high and high schools students completed the questionnaires but the parents of primary school students completed them on their behalf. the prevalence of asthma was 35.4% in tehran; this prevalence was higher in the boys (37.1%), as compared to the girls (33.5%). the prevalence of this disease has been estimated about 39.5% in pre-high schools, 35.4% in high schools and 31.6% in primary students. based on this survey, the most common clinical manifestations of asthma were: prolonged cough lasting more than 10 days (22.4%), and exercise-induced wheezing or dyspnea (16.9%), followed by repeated dyspnea or wheezing (6.4%). the prevalence of asthma is high among the students of tehran schools and it needs more careful screening programs along with additional information to the patients and parents about the disease.