Running Head: DOT and SLEEP APNEA 1

Running Head: DOT AND SLEEP APNEA 1

Sleep Apnea and DOT Drivers
Critical Appraisal Topic
Jessica Bierschbach, RN BSN, FNP-S
The University of Mary
March 14, 2014

Clinical Scenario:

A 55 year old male patient presents to the clinic for a Department of Transportation (DOT) medical card examination. On exam, patient has a body mass index (BMI) of 35, neck circumference of 18 inches, and waist circumference of 45 inches. Patient reports some daytime drowsiness and wife reports very loud snoring by patient while sleeping. Before being able to give this patient a medical card, the DOT certified examiner would require him to have an overnight sleep study to evaluate for sleep apnea.

Clinical Question:

In Department of Transportation (DOT) certified drivers, does the presence of sleep apnea cause increased crash rates when compared to drivers who do not have sleep apnea?

Articles:

Catarino, R., Spratley, J., Catarino, I., Lunet, N., & Pais-Clement, Manuel (2014). Sleepiness and sleep-disordered breathing in truck drivers: risk analysis of road accidents. Sleep Breath. 18:59-68.

Stevenson, M.R. et al. (2013). The Role of Sleepiness, Sleep Disorders, and the Work Environment on Heavy-Vehicle Crashes in 2 Australian States.American Journal of Epidemiology. 179(5):594-601. DOI 10.1093/aje/kwt305.

Summary and Appraisal of Key Evidence:

Study 1

To assess the association of sleep disorders and crash rates, Stevenson et al. investigated the crash rates of drivers in two Australian states between the years 2008 and 2011. The researchers conducted a case-control study consisting of 530 heavy-vehicle drivers with recent police reported crashes and 517 heavy-vehicle drivers with no recent crashes. The participants wore nasal cannula monitors for one night to assess for obstructive sleep apnea. According to Catarino et al. (2013) to be eligible, drivers had to be, “commercial, heavy-vehicle, long-distance operators traveling on a “long-haul” trip in excess of 200 km from the driver’s operating base. A heavy vehicle was defined as a heavy-rigid truck or heavy-articulated truck with a tare weight of more than 12 metric tons. For the purpose of this study, heavy buses were excluded.” Data was obtained on all drivers including data on demographic and anthropometric characteristics, health status, drug and alcohol use, sleep quantity and quality, and self-reported measures of sleepiness. The results of the research found that there were a number of human and vehicle factors associated with nonfatal, non-severe crashes. The study also found that there was a higher risk of crashing between the hours of midnight and 0559. The incident of crashes increased significantly if drivers had driven for more than four hours without taking a break. Even though the prevalence of sleep apnea was high in the case and control groups, the researchers did not find the presence of objectively measured sleep apnea to be associated with crash risk among heavy-vehicle drivers.

A strength recognized with this study includes the large number of participants that were involved. Limitations of this study included only looking at two states in Australia that both have different regulations for heavy vehicle drivers. Another limitation is that not all drivers completed objective testing for obstructive sleep apnea because it is possible that drivers were concerned about the diagnosis of sleep apnea since it is a reportable diagnosis to state authorities. Some divers could have not been willing to complete testing because the results may affect their ability to keep their jobs.

Study 2

In order to determine a clear association between sleep-disordered breathing and traffic accidents, Catarino, Spratley, Catarino, Lunet, and Pais-Clement evaluated 714 Portuguese truck drivers using a questionnaire that was made up of sociodemographic data, personal habits, previous accidents, Epworth Sleepiness Scale, and Berlin questionnaire. The results of this study showed that 20% percent of drivers had excessive daytime sleepiness and 29% were at a high risk for having obstructive sleep apnea. The researchers found that there was a high prevalence of excessive daytime sleepiness and other sleep disorders. The study also claimed that accident risk was related to sleepiness and anti-depressant use.

The limitations of this study include lower than desirable response to questionnaire and the fact that information may not be absolutely reliable due to the questionnaire based study and that some drivers may underreport their symptoms.

Clinical Bottom Line:

In the United States, heavy-vehicle related crashes account for 8% of all road deaths even though they account for only 1% of all vehicle registrations (Catarino et al., 2013). Accidents involving heavy-vehicles are an important public health hazard because they are usually associated with severe crashes. Studies have shown that more than half of such crashes involve fatal or incapacitating injuries and the truck driver is found at fault in more than 80 % of the cases (Catarino et al., 2013). Sleep appears to be related to around 15 to 20 % of accidents. Reports have shown that driving skill impairment from sleepiness can even exceed those from alcohol and other drugs, such as antidepressants and antihistamines (Catarino et al., 2013).

Implications for Practice:

Despite the fact that some studies donot find an association between obstructive sleep apnea and crashes, it should be noted that there is a high incidence of obstructive sleep apnea in the trucking population. This indicates the presence of significant risk factors for cardiovascular and metabolic comorbidities that may compromise heavy vehicle driver health. Although some studies have demonstrated conflicting results regarding the relationship between accident risk and sleep disorder,screenings should done on commercial drivers due to the associated health risks with obstructive sleep apnea.

References