Tehran University of Medical Sciences Journal of Sleep Sciences 2476-2938 2 1-2 2018 02 13 13 19 EN Abolhasan Halvani Department of Internal Medicine, School of Medicine, Yazd Medical Science Branch, Islamic Azad University, Yazd, Iran Farnoosh Ebadi Department of Internal Medicine, School of Medicine, Yazd Medical Science Branch, Islamic Azad University, Yazd, Iran Amir Houshang Mehrparvar Department of Occupational Medicine, School of Medicine, Shahid Sadoughi University of Medical Sciences, Yazd, Iran Mohammad javad Zare Sakhvidi Department of Occupational Health, School of Health, Shahid Sadoughi University of Medical Sciences, Yazd, Iran Raziyeh Soltani Gerdfaramarzi Department of Occupational Medicine, School of Medicine AND Industrial Diseases Research Center, Shahid Sadoughi University of Medical Sciences, Yazd, Iran Mehrdad Mostaghaci Department of Occupational and Environmental Medicine, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran 2017 07 17 2017 11 11 Background and Objective: Obstructive sleep apnea syndrome (OSAS) is a breathing disorder during sleep and de-fined as unexplained sleepiness during the day, with a minimum of five obstructive respiratory events per hour of sleep. This study aimed to evaluate the compliance to continuous positive airway pressure (CPAP) in patients with OSAS. Materials and Methods: This cross-sectional study was conducted on OSAS patients whose polysomnography test was performed at least 1 year before, and CPAP was prescribed for them. Apnea–hypopnea index (AHI) and patients’ demographic information were recorded. Results: This study included 105 patients with OSAS. The mean AHI score was 40. Patients were distributed into three groups according to their AHI: Mild (5 ≤ AHI < 15): 20 patients (19%), moderate (15 ≤ AHI < 30): 25 patients (23.8%), and severe (AHI ≥ 30): 60 patients (57.1%). Patients were divided into three groups based on their use of CPAP: 27 (25.7%) patients were regular users of CPAP, their time average use was 5.4 hours a day; 11 (10.4%) patients were in the group who stop using their CPAP, their average of time use was 6.4 hours a day; and 67 (63.8%) patients were in the group who did not use the CPAP. Conclusion:The long-term adherence to CPAP in patients with OSAS was 25%, which correlated significantly with their financial situation, while there was no significant association between the use of CPAP with age, sex, educational status, and the severity of sleep apnea. https://jss.tums.ac.ir/index.php/jss/article/view/72