Objective: Asthma is one of the most common respiratory disorders. There have not been any studies assessing the prevalence rate for asthma based on spirometry in an adult population in the west of Iran. The aim of this study was to assess the prevalence of asthma in an adult population in Khorramabad, in the west of Iran.
Methods: This prospective cross-sectional study was done on adult residents in Khorramabad between 2009 and 2010. The samples were selected by cluster and systematic sampling methods. The interviewers went to the selected homes and evaluated the samples by the standard questionnaire of the European Community Respiratory Health Survey. The individuals who were susceptible to asthma were evaluated using a hand-held spirometer (ZAN 100, Obertulba, Germany). Also, in the patients whose first spirometry had been normal, a more than 10% reduction in forced expiratory volume in one second (FEV1) after the exercise and more than 12% rise in FEV1 after the salbutamol spray inhalation was considered as having asthma. Finally, the data were summarized using means and percentages.
Results: Eight hundred and fifty-seven adults were evaluated by the questionnaire and 450 were referred to the pulmonologist office due to the aptness of asthma. The frequency of spirometry-diagnosed asthma in the adult residents of Khorramabad was 9.45%.
Conclusion: The prevalence of asthma in Khorramabad in our study was more than in similar studies in Iran and other countries. Doing analytical studies on the prevalence of asthma and its risk factors is recommended.