科学美国人60秒:Drowsy Driving Kills 6,400 Americans Annually

“It's particularly concerning that 56 million Americans a month admit that they drive when they haven't gotten enough sleep and they are exhausted.”

Charles Czeisler. He’s the director of the Division of Sleep Medicine at Harvard Medical School.

“Eight million of them lose the struggle to stay awake and actually admit to falling asleep at the wheel every month—causing more than a million crashes every year, 50,000 debilitating injuries…and 6,400 deaths.”

He spoke at a recent Harvard T. H. Chan School of Public Health Forum called Asleep at the Wheel: Drowsy Driving and Public Health.

“And we just finally got a consensus group, the first consensus panel of experts, to agree that if an individual has had less than two hours of sleep in the previous 24 hours that that's the equivalent of being negligent and should be added to the statutes. It's just like drunk driving.

“So there are three groups that are particularly vulnerable. Young people think that because they're young, they're fit—they can do anything—that they would be the most resilient in the face of sleep deprivation. But actually young people are the most vulnerable…there's actually a biological reason…so as we get older we lose cells in the sleep switch in the brain, in the hypothalamus, that help us make the transition from wakefulness to sleep…when we keep an 18-year-old awake all night and compare that to keeping a 70-year-old awake all night, the 18-year-old will have 10 times as many involuntary lapses of attention than the older person. So young people are more vulnerable, not less, to the effects of sleep deprivation.

“The second group that is particularly vulnerable are night shift workers…and the third group that is particularly vulnerable are people with sleep disorders, particularly sleep apnea. One out of three men and one out of six women have sleep apnea. And yet, 85 percent are undiagnosed and untreated. And it more than doubles the risk of crashes.”

The entire hour-long forum featuring Czeisler and other researchers discussing drowsy driving is archived on line. Just google “Harvard public health forum”.

—Steve Mirsky