Tehran University of Medical Sciences Iranian Journal of Allergy, Asthma and Immunology 1735-1502 19 6 2020 12 19 660 666 Marzieh Tavakol Non-Communicable Diseases Research Center, Alborz University of Medical Sciences, Karaj, Iran Seyde Marzie Abhari Department of Pediatrics, Imam Ali Hospital, Alborz University of Medical Sciences, Karaj, Iran Fatemeh Moosaie School of Medicine, Tehran University of Medical Sciences, Tehran, Iran Mina Rasmi Non-Communicable Diseases Research Center, Alborz University of Medical Sciences, Karaj, Iran Mahmood Bakhtiyari Non-Communicable Diseases Research Center, Alborz University of Medical Sciences, Karaj, Iran Leila Keikavoosi-Arani Department of Healthcare Services Management, School of Health and Research Center for Health, Safety and Environment, Alborz University of Medical Sciences, Karaj, Iran Kiomars Poorrostami Department of Pediatrics, Imam Ali Hospital, Alborz University of Medical Sciences, Karaj, Iran Homa Sadri Non-Communicable Diseases Research Center, Alborz University of Medical Sciences, Karaj, Iran AND Department of Pediatrics, Imam Ali Hospital, Alborz University of Medical Sciences, Karaj, Iran 2020 04 18 2020 08 31 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 exercise-induced 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. https://ijaai.tums.ac.ir/index.php/ijaai/article/view/2797