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Study: Lack of Sleep, Poor-Quality Sleep Cause Drowsy Driving Accidents

New research shows that lack of sleep and poor sleep can cause drivers to fall asleep behind the wheel and get into serious and potentially fatal car accidents.

Authors of the study published this month by the online research journal PLOS ONE concluded that 6 to 10 percent of motor vehicle accidents are caused by sleepiness – also known as fatigued or drowsy driving.

Sleep duration of fewer than six hours a night, a person’s belief that their sleep was of poor quality and “medicinal drug consumption” also contributes to car accidents, the study found. Drowsy driving accidents mainly involve young people (18 to 30 years old), according to the researchers.

Drivers who had fewer than six hours of sleep a night for three months prior to the study exhibited “almost a two-fold increased risk” of crashing their vehicles after falling asleep at the wheel.

A little more than half of the drivers who reported insufficient sleep also reported sleep complaints such as difficulty falling asleep and/or waking repeatedly and/or awakening prematurely.

The study also found that patients treated for illness, injury and/or pain have a higher risk of traffic accidents than patients in good health. Drivers who had taken two or more medications had an increased risk of accidents.

“We do not know whether side effects of drugs are really involved in this increase in the accident rate or whether the disease itself and/or the pain are confounding factors,” the study authors said.

Emotions, Too, Contribute to Auto Accidents, Researchers Find

In addition to analyzing the impact of drowsiness on drivers, the study’s authors found that emotional states such as anger or anxiety can lead to a pattern of negative and dangerous driving. On the other hand, experiencing occupational stress on the previous day appeared to be “a protective factor” for drivers.

This finding and similar results in other studies suggest that a moderate level of distress or occupational stress may encourage more cautious driving behavior, the researchers said.

The study’s authors said road safety campaigns should encourage drivers to get a good night’s sleep all year long. Physicians should advise their patients who report not sleeping well sleep about drowsy driving risks.

How to Prevent Drowsy Driving

The National Sleep Foundation estimates that 100,000 crashes each year are caused by fatigued drivers, and 55 percent of drowsy driving crashes are caused by drivers younger than 25 years old.

The NSF reports that a good night’s sleep is between 7 to 9 hours of sleep per night for adults and 8.5 to 9.5 hours a night for teens.

Individuals who suffer frequent daytime sleepiness often have difficulty sleeping at night and should consult their physicians or a local sleep disorders center for diagnosis and treatment.

To prevent drowsy or fatigued diving, the NSF suggests:

  • Getting a good night’s sleep.
  • Having a companion who stays awake and talks to the driver on long trips. Passengers can also watch for signs of fatigue and replace a drowsy driver.
  • Scheduling stops every 100 miles or two hours.
  • Not consuming alcohol or medications (over-the-counter and prescribed) before getting behind the wheel.

If you have been involved in an auto accident that was caused by another person, drowsiness may have been a factor. Contact Powers & Santola, LLP, to receive a free consultation.

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