Tehran University of Medical Sciences Journal of Sleep Sciences 2476-2938 3 3-4 2019 06 12 63 67 EN Arezu Najafi Occupational Sleep Research Center, Baharloo Hospital, Tehran University of Medical Sciences, Tehran, Iran Nafiseh Naeemabadi Occupational Sleep Research Center, Baharloo Hospital, Tehran University of Medical Sciences, Tehran, Iran Maryam Saraei Center for Research on Occupational Diseases, Tehran University of Medical Sciences, Tehran , Iran Khosro Sadeghniiat-Haghighi Occupational Sleep Research Center, Baharloo Hospital, Tehran University of Medical Sciences, Tehran, Iran Masoomeh Mahmoodi-Afsah Center for Research on Occupational Diseases, Tehran University of Medical Sciences, Tehran , Iran Ania Rahimi-Golkhandan Occupational Sleep Research Center, Baharloo Hospital, Tehran University of Medical Sciences, Tehran, Iran 2018 05 20 2018 08 07 Background and Objective: Obstructive sleep apnea (OSA) is a common sleep-disordered breathing (SDB) characterized by intermittent hypoxemia (IH). OSA and IH are considered risk factors for increased hearing thresholds as well. Furthermore, thresholds of speech frequency affect personal fitness for driving. Thus, main purpose of this study was to assess the association between speech frequency thresholds and OSA among commercial drivers. Materials and Methods: This cross-sectional study was conducted on 1000 commercial drivers who were referred to obtain a health license at the Occupational Medicine Clinic of Baharloo Hospital, Tehran, Iran. Blood pressure, neck size, weight, and height were recorded. Validated Persian version of Epworth Sleepiness Scale (ESS) and STOP-BANG questionnaire were completed by the participants. STOP-BANG score ≥ 3 was defined as high risk for OSA. Fast blood sugar (FBS), triglyceride (TG), and total cholesterol (TC) were measured for all drivers. Hearing threshold levels of all subjects were recorded by pure tone audiometry (PTA) in frequencies of 500, 1000, 2000, and 3000 Hz for each ear in decibels (dB). Results: The mean age of the participants was 43.0 ± 9.9 years. The mean ESS and STOP-BANG scores of the participants were 3.1 ± 2.8 and 1.8 ± 0.8, respectively. 237 (23.7%) drivers were high-risk for OSA. Participants with OSA had significantly higher thresholds of speech frequencies compared to the low-risk ones (P < 0.0001). Conclusion: OSA may be also considered as a risk factor for increased thresholds of speech frequency among commercial drivers. During drivers’ periodic medical examination, evaluation of OSA as a strong risk factor for increasing hearing thresholds is recommended. https://jss.tums.ac.ir/index.php/jss/article/view/106