Even the Well Rested May Be Driving Drowsy

Think getting a solid five to six hours of shut eye a night will ensure you’re well rested and ready to drive? Think again, say researchers at the University of Pennsylvania.   

A team at the Center for Sleep and Circadian Neurobiology at Penn’s Perelman School of Medicine found that people who on average sleep fewer than six hours each night are three times more likely to report having driven while drowsy in the last month, compared with people who get seven or more hours a night.  People who sleep five or fewer hours a night are four times as likely to report drowsy driving, compared with their seven or more hour counterparts. 

Falling asleep at the wheel is a major cause of accidents.  But researchers noted it might even be more of a problem than drunk driving, since it’s responsible for more serious crashes each year.  “We know that people who are sleep-deprived in the lab have impaired driving performance,” said Dr. Michael Grander, “but we haven’t been able to better define what sleep profiles and patterns put drivers in the general population at the highest risk.” 

A recent study in the Journal of the American Medical Association’s Internal Medicine found that, like drunk driving, drowsy driving doubles a motorist’s crash risk. Sleepiness can impair driving by causing slower reaction times, vision problems, lapses in judgment, and delays in processing information. Being awake for more than 20 hours results in impairment equal to a blood alcohol concentration level of 0.08%.   

It’s also possible to fall into a 3- to 4-second micro-sleep without realizing it.  A Centers for Disease Control study released earlier this year showed that one in 24 adults in the U.S. has reported falling asleep at the wheel. These numbers may be even higher, since nodding off while driving can happen so quickly and may go unnoticed. 

While the amount of sleep each person requires varies, the National Sleep Foundation recommends that adults get between seven and nine hours a night and teens get even more. Sleep is vitally important for teens, the group with the highest crash risk. A AAA Foundation for Traffic Safety study conducted in 2012 found that one in seven licensed drivers 16 to 24 years of age admitted to nodding off at least once while driving in the past year, compared to one in ten of all licensed drivers who drove drowsy. 

To reduce the number of fatigue-related crashes and save lives, the National Sleep Foundation sponsors Drowsy Driving Prevention Week. This year, the campaign takes place November 3-10, which coincides with the end of daylight savings time. So in addition to setting your clocks back one hour next Saturday (November 2), be sure to take advantage of that extra hour to catch up on some ZZZZZs.