Even though it's slightly overshadowed by that other big national event this week, the National Sleep Foundation reminds us that this week (Nov. 1-8) is Drowsy Driving Prevention Week. NSF says drowsy driving is reaching epidemic proportions in 2020, with an estimated 100,000 police-reported crashes involving drowsy driving every year in the U.S. According to one report from the Governors Highway Safety Association, an estimated 5,000 people died in 2015 in crashes involving drowsy driving.
The frightening thing is many drivers admit to drowsy driving and even falling asleep at the wheel. According to the NSF, about half of U.S. adult drivers admit to consistently getting behind the wheel while feeling drowsy. About 20% admit to falling asleep behind the wheel at some point in the past year, with more than 40% admitting this has happened at least once in their driving careers.
According to the National Highway Traffic Safety Administration, every year about 100,000 police-reported crashes involve drowsy driving. These crashes result in more than 1,550 fatalities and 71,000 injuries. The real number may be much higher, however, as it is difficult to determine whether a driver was drowsy at the time of a crash.
And beyond the human toll is the economic one. NHTSA estimates fatigue-related crashes resulting in injury or death cost society $109 billion annually, not including property damage.
The NSF doesn't mention truck drivers in particular in its statistics on drowsy driving, but surely there are a few incidents within these numbers. Commercial drivers are, of course, subject to hours of service rules intended to mitigate the impact of fatigue, but they don't always have the intended effect. In some cases, they can exacerbate the problem for drivers whose schedules are turned upside-down.
Nor do the rules account for individuals' need for sleep. Some people biologically require six or seven hours of sleep, while others may require eight or nine. Nor do the rules — and probably few fleet operations departments — account for drivers' personal chronotypes, whether they are a night owl or a morning person.
"Some of the rules that are intended to protect drivers are great, but some of these duty-cycles create consequences and problems because they're not particularly well thought out," says Chris Winter, a board-certified neurologist and an internationally recognized sleep expert with his own practice, Charlottesville Neurology and Sleep Medicine, in Charlottesville, Virginia. "The rules don't take individual chronotypes into account. For example, I'm a much more dangerous driver in the morning than I am at night. But if you restrict my ability to drive at night, are we really making things that much safer for me and for the people on the road when I'm driving?"
Winter was the subject of our latest HDT Talks Trucking podcast episode, The Need for Sleep. He describes some of the problems that can arise from not getting sufficient sleep over a long period.
He says lack of sleep can affect almost every organ and system in the body in some way, including our immune systems, cardiovascular system, and even our moods. Do you ever wonder why you feel a bit grumpy on Fridays? Lack of sleep may have something to do with it.
"When individuals don't get the sleep they need, they tend not to make great decisions," he says. "Sleep-deprived individuals tend to suffer a decline in short-term concentration, as well as their ability to focus. It also affects their mood and interestingly, the ability to interpret the moods or the feelings of somebody that we're talking to."
Those are common but lesser-known manifestations of a lack of sleep. Some of the more commonly associated problems can be the vascular effects, like hypertension, and the risk of heart attacks and strokes.
"You can go all the way down the list to even how we look," he says. "Lack of sleep tends to age our appearance. I tell people that sleep loss is sort of like rust; it just kind of eats away at whatever you're talking about."
If insufficient sleep isn't enough a problem, irregular sleep schedules can wreak havoc on our bodies, too. Everything that happens inside us is based on a highly regulated internal clock, called a circadian rhythm. We are biologically wired to sleep at night and be awake and alert during the day, which is pretty obvious. What's not so obvious is what happens to digestion and other processes when you eat a meal at 3 a.m., when your system thinks it should be sleeping.
"And so, what happens with a truck driver who is driving all around the clock? If you ask them when they go to bed, when do they wake up, when do they drive, when do they rest, they can't answer the question because every day is different," Winter observes. "If you could peer deep inside that individual's brain and body, you'd see all these other processes – digestion, metabolism, cognition – are all going to be sort of haphazard as well."
Even shift workers have a fighting chance of regulating some bodily functions if they stay on a certain shift for a period of time, but drivers who start and stop and different times of the day quickly throw those functions into disarray.