Sleep Deprivation & Car Accidents: How Drowsy Driving Is Like Drunk Driving

Motor vehicle crashes rank among the top causes of death in the U.S.  Sleepy driving is the leading or contributing factor in 21% of fatal crashes, according to the AAA Foundation for Traffic Safety. The research also finds that drivers who don’t get enough sleep are to blame for 7% of all collisions and 13% of collisions that result in a hospital admission. If you get less than five hours of shut-eye a night, or have slept for less than seven hours in the last 24 hours, your odds of being involved in a crash are greatly increased. In fact, sleepy driving can look a lot like drunk driving. Driving after only four to five hours of sleep is similar to the National Highway Traffic Safety Administration’s estimates of the danger of driving with a blood-alcohol concentration at or above the legal limit of 0.08%. And while drowsy driving usually occurs when an individual hasn’t gotten enough sleep, it can also happen due to medications, sleep disorders, alcohol or shift work.

Sleep Deprivation Facts

Sleepy drivers are not only putting themselves at risk, but everyone on the road around them as well. Despite the fact that most people understand that driving when they’re drowsy is risky, many are inclined to believe that it’s other sleep-deprived drivers on the road who present a danger, not themselves. Here are some additional sleep deprivation facts:

  • Research shows that most collisions caused by sleepy driving happen from midnight to 8 a.m.
  • Most of the time, there are no passengers in the vehicle. The lone driver has no one to talk to so they can stay alert.
  • Young males, who are naturally prone to risk-taking behavior, are most at risk for driving while sleep-deprived. They may work long hours or just stay up late.
  • In the majority of crashes caused by sleepy driving, a lack of skid marks indicates there was no attempt to stop.

Symptoms of Sleep Deprivation

Sleep deprivation slows reaction time and leads to significant lapses in attention. When you skimp on sleep, you’re likely to be more irritable and impatient — two emotions that don’t make for safe driving. You’re also more impulsive, another feeling that can lead to risky driving. When sleep-deprived, your memory suffers. You may find yourself wondering, “What was that exit I was supposed to take?” Then you check your phone just as a Highway Patrol officer has pulled up even with you. You may also feel hungrier than usual. Inadequate sleep can increase the levels of ghrelin (known as the “hunger hormone”) in the gut. Another of the symptoms of sleep deprivation is having trouble seeing. A shortage of shut-eye impacts the ciliary muscle, which helps your eyes focus.

Alcohol Multiplies the Risk Exponentially

Drivers who have consumed alcohol are already at a disadvantage on the road. Research shows that even after one drink, a driver’s reaction time and judgment are impaired. When that same individual is running low on sleep, their physical and mental alertness are severely compromised. A recent study found that one beer had the same effect on a person with four hours of sleep as six beers had on a fully rested individual. Many drivers will not even realize they’ve dozed off for 10-15 second micro naps, which can have disastrous results. The best decision a sleepy driver can make is to pull off the road. And make no mistake. Stopping for fresh air or a caffeine fix does not make up for getting adequate rest. These are just quick fixes that won’t hold you for long. Find a hotel or call for a ride. Lives may depend on it. Source: Acute Sleep Deprivation and Crash Risk: https://www.aaafoundation.org/acute-sleep-deprivation-and-crash-risk Drowsy Driving: https://sleepcenter.ucla.edu/drowsy-driving

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