More than 6,000 people die in drowsy driving-related crashes in the US each year, a recent study suggests.
Millions of US drivers fall asleep at the wheel each month, and roughly 15 percent of all fatal crashes involve a drowsy driver, researchers note in the journal Sleep.
“Drowsy driving is not just falling asleep at the wheel; it mimics alcohol-impaired driving in many ways,” said lead study author Stephen Higgins, a researcher at the National Highway Traffic Safety Administration in Washington, DC.
“Drowsiness leads to slower reaction times and impaired attention, mental processing, judgment and decision making,” Higgins added by e-mail.
Getting enough sleep every night is the best defense against drowsy driving, Higgins and colleagues note.
When that’s not possible, a nap to break up the road trip may still help drivers remain more alert behind the wheel.
“If you start to get sleepy while you’re driving, pull over for a short 20- to 30-minute nap in a safe place, such as a lighted designated rest stop,” Higgins said. “You can also combine a caffeinated drink with the nap — this has been shown to increase alertness in scientific studies but only for short time periods.”
For the study, Higgins and colleagues examined data from previously published research on drowsy driving to identify the main causes of the problem and potential ways to prevent it.
Many lifestyle factors can influence the odds of drowsy driving, they note. These include working long and irregular hours, working night shifts and having multiple jobs.
To calculate the toll of drowsy driving, researchers examined crash data from 2010.
They found 32,999 total fatal crashes and 3.9 million total injury crashes.
Drowsy driving accounted for about 5,445 fatal crashes and 510,900 non-fatal collisions, for a total estimated societal cost of $109 billion per year, based on the 2010 figures.