Study: Drivers who experience shift work sleep disorder are 3x more likely to be involved in a vehicle crash

Researchers from the University of Missouri College of Engineering looked into the relationship between vehicle accidents and sleep disorders like sleep apnea or insomnia.

Non-traditional workers, such as those who work from 11 p.m. to 7 a.m. or the “graveyard”, are more likely than those with regular daytime hours to develop a sleep disorder called shift work sleep disorder. This condition disrupts their sleep and can lead to chronic medical conditions. Researchers at the University of Missouri found that people with this condition are three times more likely than others to be in an automobile accident.

Praveen Edara is the department chair and professor in civil and environmental engineering. “This discovery has many important implications. These measures could include roadside and in-vehicle messaging, highway rest areas, and roadside messaging to increase a driver’s attention. They also can be used to encourage drivers with late-night shifts to use other modes of transportation such as public transit or ride-share.

Edara, one the authors of the study, stated that the analysis was based upon data from a real-world driving test for the second Strategic Highway Research Program, which was established by Congress.

In recent years, customer demand has increased for 24/7 business operations. The traditional work day, once 9 a.m.-5: p.m., has been extended for many to include night and evening shifts. This has led to sleep disorders and shift work sleep disorder. Edara stated that he was shocked to see shift work sleep disorder increase traffic crash risk by almost 300%. This is in contrast to sleep apnea or insomnia which each increased crash risk by about 30%.

Edara stated that previous studies had shown that sleep disorders can increase the likelihood of a traffic accident. However, most of these studies were done in controlled environments such as a simulator driving in the laboratory. These studies are now supported by real-world data.

Edara stated that in the past, sleep disorders have been studied primarily in controlled environments, such as driving simulators and test-tracks. “Our study takes this one step further, using actual crash and near-crash data from around 2,000 events in six U.S. States. While we know for some time that sleep disorders increase crash risks, here we can quantify this risk using real-world crash data and account for confounding variables like roadway and traffic characteristics.

Edara stated that some limitations to their study included not having data on fatal crashes and not being able to measure drowsiness.

A national problem is being highlighted

The National Transportation Safety Board (or NTSB) is the federal agency responsible for investigating major traffic accidents in the United States. They issue an annual “most desired list” of safety improvements each year. Their 2019-2020 list includes “screening & treating obstructive sleeping apnea”, one of the top 10 topics.

Edara stated that he hopes that the research will show the dangers of traffic accidents caused by excessive sleepiness. This will help researchers to find ways to make people safer behind the wheel. To better understand the reasons for this, Edara suggested that medical experts in this field would be the best next step in this research.

Edara stated that “we want to work with medical and public health professionals who are experts in sleep-related research to better understand the reasons this is happening.” “This will allow us to examine what countermeasures can be developed and tested to improve safety for these drivers and other motorists.”

Safety Science published the study “Sleep disorders, risk of traffic accidents: A naturalistic driving study study analysis.” Carlos Sun from the MU College for Engineering was co-author, as well as Nipjyoti Bhadwaj of the Federal Highway Administration. The Federal Highway Administration recently awarded funding. The authors are solely responsible for the content and do not necessarily reflect the official views or funding agencies.

Updated 01/18/22