Study: Truckers not getting enough shut eye
Drivers average less than 5 hours of sleep a night
September 10, 1997
Web posted at: 9:20 p.m. EDT (0120 GMT)
BOSTON (CNN) -- A new study shows that long-haul truckers in North America may not be getting the sleep they need to be at optimum performance behind the wheel.
A study of 80 truckers, reported in this week's New England Journal of Medicine, showed that they got an average of less than five hours of sleep per night, even when given eight uninterrupted hours of downtime after a day behind the wheel, as required by law in the United States and Canada.
"That level of sleep deprivation leads to performance impairment," said Merrill Mitler of the Scripps Clinic and Research Institute in San Diego, principal author of the study. "People who are that sleepy miss signals, they make mistakes. They can actually fall asleep when they don't want to."
More than half of the truckers in the study, who were videotaped as they drove, experienced at least one six-minute interval of drowsiness while driving. Truckers were most vulnerable to drowsiness late in the night or early in the morning, when the body naturally wants to shut down.
More than 110,000 people are injured and 5,000 killed in the United States each year in commercial truck accidents. The Highway Traffic Safety Administration estimates that perhaps 30 percent of those deaths, and 70 percent of the injuries, are directly attributable to accidents caused by sleep deprivation.
In the United States, drivers must be given eight hours off after driving a total of 10 hours. In Canada, they get eight hours off after 13 hours behind the wheel.
But researchers found that in one out of every eight trips, drivers didn't take their full rest period. And even when they took the full allotment of time off, they often didn't use the time to sleep.
Some of them said they needed to unwind before going to bed, while others felt more like reading, watching television and socializing than spending all of their off time asleep.
Most drivers told researchers that they felt they needed about seven hours of sleep a night. But those who always worked during the day averaged just 5 3/4 hours of sleep, and those who always worked at night got an average of only 4 1/2 hours.
The results of the study have prompted its sponsor, the Federal Highway Administration, to rethink its rules for how drivers' sleep time is scheduled.
"We want to focus more on rest periods than on working periods to try to give some consistency to drivers' schedules so they can expect to rest roughly at the same times day to day," says Paul Brennan, the agency's head of research and standards.
But sleepy truckers may not be the only menace on the road. In an editorial accompanying the article, Dr. William Dement of Stanford University said the findings reflect his belief that "pervasive drowsy driving is an established fact in the United States," with more than half of the general public driving while sleep deprived.
"We're beginning to realize that drowsiness or sleep deprivation, fatigue, is beginning to outstrip alcohol as a cause of accidents in transportation, particularly on the highway," Dement said.
Medical correspondent Linda Ciampa and Reuters contributed to this report.