prevalence of asthma symptoms in 13-14-year-old adolescents in karaj

Asthma is the most common chronic inflammatory respiratory disorder in children. this study was designed to assess the prevalence of asthma in 13-14-year-old adolescents in karaj, alborz province in iran, using the international study of asthma and allergies in childhood (isaac) questionnaire. totally 950 adolescents attending 40 schools located in 4 regions of karaj city were enrolled in the survey. the persian version of the isaac questionnaire was filled by 13-14- year-old students. multi-stage clustered random sampling was used to divide the city of karaj into four educational districts. ever wheezing was reported in 22% of the individuals; 10.52% claimed to have wheeze in the last 12 months and 22.73% had during or after exercise. the experience of wheezing in the last 12 months was more prevalent among males (11.73% vs. 9.38%; p<0.05). however, having a history of asthma was higher among males (7.55% vs. 3.47%; p<0.05). history of hospitalization (60.8%), family history of asthma (49.4%), and history of food allergy (42.3%) were found to be the most frequent characteristics significantly associated with ever wheezing (p<0.05). the prevalence of wheezing in the last 12 months, as a major index of current asthma, was 10% which was close to the national average. however, nocturnal cough and exerciseinduced wheezing were higher in karaj compared to other cities of iran; which could be related to the high level of air pollution in this industrial area.