ORIGINAL ARTICLE Screening for Sleep Disordered Breathing Among Applicants for a Professional Driver’s License Orna Tzischinsky, PhD, Ayala Cohen, PhD, Etti Doveh, PhD, Rachel Epstein, MA, Josi Ribak, PhD, David Klein, PhD, Giora Pillar, PhD, and Peretz Lavie, PhD Objectives: Individuals with sleep disordered breathing (SDB) are at high risk for falling asleep while driving. The aim of this study was to identify variables that would predict SDB among healthy young applicants for a pro- fessional driver’s license. Method: A total of 301 applicants for a driver’s license completed self-administered questionnaires. Sleep was recorded for one night with the Watch peripheral arterial tone–100. To identify possible predictors of SDB (Respiratory Disturbance Index >15), we employed new statistical methods. Results: The following items were identified as signif- icant predictors of SDB: body mass index, age, Mini Sleep Questionnaire, smoking, father snoring, afternoon nap-taking, and falling asleep while trav- eling as a passenger. Moderate or severe SDB was prevalent in at least 25% of the applicants. Conclusion: New statistical methods revealed that a com- bination of questions related to sleep habits, complaints, and demographic data predicted most of the clinically significant SDB. E xcessive daytime sleepiness (EDS) is known to impair the day- time performance of individuals afflicted by it. Sleep disordered breathing (SDB), and specifically obstructive sleep apnea (OSA), is the most common sleep disorder causing EDS. 1,2 It has been shown that individuals with SDB are at high risk for falling asleep while driving and are therefore involved in more motor vehicle crashes. Furthermore, the severity of SDB predicts the number of accidents. 3–5 According to Horne and Reyner, 6 motor vehicle crashes related to EDS account for between 15% and 20% of all accidents and between 29% and 50% of all deaths and serious injuries. Recent studies 4,7 have shown that motor vehicle crashes are about 2 to 7 times higher among drivers with OSA than in healthy individuals and are associated with more injuries, even in patients with mild OSA. This increased risk has been documented in many countries around the world, including Australia, Canada, France, Germany, Israel, Spain, Switzerland, Turkey, the United Kingdom, and the United States. 8–10 The rate is found to be even higher in Japan. 11 Although OSA is estimated to affect approximately 5% of the general population, 12 the condition seems to be much more prevalent in professional drivers of vehicles such as buses, taxis, heavy trucks, and ambulances. In Spain, Diaz et al 13 found that the prevalence of OSA was 8.6% among professional drivers, increasing with age. In Australia, Howard et al 7 reported that more than half (59.6%) of professional drivers had SDB, 15.8% had OSA, and 24% suffered from EDS, which increased with the severity of SDB. In a German study, Moreno et al 14 found that approximately 26% of truck drivers From the Psychology Department (Dr Tzischinsky), Emek Yezreel College, Emek Yezreel, Israel; Research Center for Work Safety and Human Engineering (Dr Tzischinsky, Ms Epstein, Dr Pillar, and Dr Lavie), Technion, Haifa, Israel; The Statistics Laboratory (Dr Cohen and Dr Doveh), Faculty of Industrial Engineering and Management, Technion, Haifa, Israel; and Medical Institute for Road Safety (Dr Ribak and Dr Klein), Ministry of Health, Haifa, Israel. This project was supported by the Safety and Health Administration, Ministry of Trade and Labor, Israel. Address correspondence to: Orna Tzischinsky, PhD, DSc, Psychology Depart- ment, Emek Yezreel College, Emek Yezreel, 19300, Israel (Orna@yvc.ac.il). Copyright C  2012 by American College of Occupational and Environmental Medicine DOI: 10.1097/JOM.0b013e31825b1bb1 were at high risk for OSA. Pack et al 15 found that 28.2% of profes- sional drivers in the United States had at least mild OSA and 4.7% had severe OSA. In Italy, Garbarino 16 reported that the occurrence of OSA in professional drivers (17%) was significantly higher than in the general population (8.6%). Truck crashes are potentially more severe due to their size, weight, and speed. 17,18 One study showed that in 7% of truck ac- cidents, the driver admitted to falling asleep behind the wheel. 17 That figure is likely an underestimation of the total proportion of truck crashes attributable to driver somnolence, which has been esti- mated as high as 20%. 15 Therefore, determining which truck drivers are most prone to EDS should be considered a major public safety priority. 19 Nevertheless, the existence of SDB often goes unrecognized, especially among the young adult population that commonly does not present the classic clinical symptoms. Recently, Bruyneel et al 20 investigated the characteristics of young adult patients (<40 years) with OSA. They found that the severity of apnea in this population was related to body mass index (BMI), male gender, neck circumference, current smoking, and African origin. Many patients, especially young ones, with OSA are found to be unaware of their SDB and thus fail to report any symptoms. 4 Thus, the actual prevalence of OSA and EDS is estimated to be approximately 3 times higher than the number of patients who are actually diagnosed, especially among the younger population. Given the high risk of motor vehicle crashes among profes- sional drivers with OSA, it is highly important to screen for SDB among applicants for a professional driver’s license. In Israel, the majority of applicants for a professional driver’s license are young (20 to 30 years old), and although they do undergo a detailed medical examination, they are not screened for SDB. Thus, the aim of this study was to identify the variables that would be useful in screening for SDB among healthy young applicants for a professional driver’s license. METHOD Participants A total of 301 applicants for a professional driver’s license were consecutively approached on randomly selected days to par- ticipate in the study. The applicants were referred to the Medical Institute for Road Safety at the Ministry of Health to ensure their suitability for a professional driver’s license, which is required in Israel to drive buses, taxis, heavy tracks, ambulances, and other such vehicles. Tools All subjects completed a battery of self-administered ques- tionnaires, including the following: Mini Sleep Questionnaire (MSQ) 21 ; Pittsburgh Sleep Quality Index (PSQI) 22 ; Epworth Sleepi- ness Scale (ESS); 23 and a demographic questionnaire. Sleep was investigated for one night with an ambulatory device called the Watch peripheral arterial tone 100 (WP100; Itamar Medical, Cae- sarea, Israel), which has been extensively evaluated and shown to accurately detect SDB. 24,25 The WP100 is a four-channel unattended ambulatory device based on the peripheral arterial tone (PAT) sig- nal with three additional channels: heart rate (derived from the PAT Copyright © 2012 Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited. JOEM  Volume 54, Number 10, October 2012 1275