Molecular and Cell Biology Research Center, Department of Physiology & Pharmacology, Faculty of Medicine, Mazandaran University of Medical Sciences, Sari, Iran,
Department of Physiology & Pharmacology, Faculty of Medicine, Mazandaran University of Medical Sciences, Sari, Iran.
Background: Despite widely available data about childhood asthma, there are limited data about the prevalence of asthma among young adults in Iran. The aim of this study was to determine the prevalence of asthma and respiratory symptoms among medical students in the city of Sari in Northern Iran. Materials and Methods: The prevalence of asthma and respiratory symptoms was studied using a standard questionnaire. Based on the information obtained from the questionnaires, the study participants were divided into two groups of asthmatics and non-asthmatics. Pulmonary function tests including forced expiratory volume in one second (FEV1) and forced vital capacity (FVC) before, and after salbutamol inhalation were measured in all subjects with asthma and approximately 10% of those without asthma. Results: A total of 1,011 subjects (374 males, 637 females) participated in this study. Asthma was found in 3.5% of the subjects (3.2% males and 3.6% females). The 12-month prevalence of wheezing, coughing at rest, coughing at night, breathlessness at rest, exercise-induced wheezing, and exercise-induced coughing in the entire study population was 11.1%, 12.4%, 13.4%, 13.3%, 17.7%, and 16.7%, respectively. The prevalence of all asthma-related symptoms was significantly higher among asthmatics compared to non-asthmatics. Moreover, asthmatic subjects showed lower FEV1 and FVC values compared to nonasthmatic subjects (p <0.001). Smoking and family history of asthma were statistically significant risk factors for developing asthma. Conclusion: The high prevalence of asthma related symptoms in the present study strongly suggests that asthma is under diagnosed and under treated among participants.