Small Amounts of Sleep Deprivation Linked to Drowsy Driving Accidents

February 2, 2017

If you are not getting at least 7 hours of sleep every day you double your risk of causing a car accident, according to a new study by the AAA Foundation for Traffic Safety. A sleep deficit of 2 to 3 hours in a 24-hour period more than quadruples the risk of a fatigued driving accident compared to drivers who get the recommended 7 hours of sleep.

The AAA Foundation based its report on an analysis of 7,234 drivers involved in 4,571 car crashes. The study may underestimate the risk of driving while sleep-deprived, because data on crashes that occurred between midnight and 6 a.m. were not available. Other studies have shown that the effects of lack of sleep on drivers’ attention and performance are greatest during the early morning hours, the study says.

The AAA Foundation study, released in December 2016,  is entitled Acute Sleep Deprivation and Risk of Motor Vehicle Crash Involvement.

“You cannot miss sleep and still expect to be able to safely function behind the wheel,” Dr. David Yang, executive director of the AAA Foundation, said.

Yang added that the quadrupled risk of a car accident after losing 2 to 3 hours of sleep is equivalent to the crash risk the National Highway Traffic Safety Administration (NHTSA) associates with drunk driving.

The NHTSA says that each year fatigued, or drowsy, driving causes almost 886 fatal crashes (2.5 percent of all fatal crashes), an estimated 37,000 injury crashes, and an estimated 45,000 property-damage-only crashes.

The car accident attorneys of Michael Kelly Injury Lawyers in Boston have long been particularly concerned about drowsy driving accidents. We have seen the serious injuries or fatalities caused by drivers who were sleepy and struggling to stay awake. Fatigued drivers have reduced awareness of traffic conditions, slower reactions, and may not brake or swerve to avoid a crash. If a drowsy driver has fallen asleep, a fatigued driving collision may occur with a vehicle traveling at or near full speed.

A Centers for Disease Control and Prevention report from July 2014 said that in about 3.3 percent of car accidents in Massachusetts involving drivers 18 years old or older, the driver admitted having fallen asleep while driving at least once within 30 days of a crash.

The current AAA Foundation study focuses on the relationship between specific amounts of sleep deprivation and crash risk among the general driving population. However, the study says previous AAA Foundation research has estimated that a drowsy driver was involved in 7 percent of all crashes in which a vehicle was towed from a scene, 13 percent of all crashes that resulted in hospitalization, and 16-21 percent of all fatal crashes.

The AAA Foundation has reported previously that young adult drivers, ages 19-24, are the most likely to admit to driving while drowsy. A third of young drivers said they had driven while drowsy in the prior month. Many are students who have erratic sleep schedules. By comparison, older drivers (ages 75+) and the youngest (ages 16-18) were the least likely to report fatigued driving.

Drowsy Driving Accident Study Key Findings

Among the key findings of the new AAA Foundation study are that, compared to drivers who had slept for at least 7 hours in the previous 24 hours, drivers who reported they had slept:

  • 6-7 hours had 1.3 times the crash rate
  • 5-6 hours had 1.9 times the crash rate
  • 4-5 hours had 4.3 times the crash rate
  • Less than 4 hours had 11.5 times the crash rate.

The study considered what drivers said was their usual amount of sleep. Drivers who reported that they usually slept for 4 to 5 hours per day had 5.4 times the crash rate of drivers who usually slept 7 hours or more daily.

Compared to drivers who reported that they had slept at least their usual amount in the past 24 hours, drivers who reported they had slept:

  • 1-2 hours less than usual had 1.3 times the crash rate
  • 2-3 hours less than usual had 3 times the crash rate
  • 3-4 hours less than usual had 2.1 times the crash rate
  • 4 or more hours less than usual had 10.2 times the crash rate.

A National Sleep Foundation consensus working group concluded that individuals who have slept 2 hours or less within a 24-hour period are not fit to operate a vehicle. The results of the current study suggest that individuals who have slept for less than 4 or 5 hours in the previous 24 hours are likely to be substantially impaired.

The AAA Foundation estimated crash risk associated with driving after only 4 to 5 hours of sleep is similar to the NHTSA’s estimates of the crash risk associated with driving with a blood-alcohol concentration (BAC) equal to or slightly over the legal limit for alcohol in the U.S. The risk increases as the number of hours of sleep decreases. The crash risk associated with driving after having slept less than 4 hours in the previous 24 is comparable to the accident risk associated with getting behind the wheel with a blood alcohol concentration of roughly 0.12-0.15.

Are You At-Risk of a Drowsy Driving Accident?

It is important for all drivers to recognize the amount of sleep they have had and its effect on their ability to operate a motor vehicle safely. Every driver must take the appropriate action if he or she has not had enough sleep or has become drowsy. Take a rest break and let someone else drive or find a safe place to take a short nap. Get out from behind the wheel.

The National Sleep Foundation has identified specific groups who are at risk for drowsy driving. They are:

  • Young people, especially males younger than 26 years old.
  • Shift workers and people who have rotating day and night work hours. Working the night shift increases your risk of driving while fatigued by nearly 6 times, the NSF says. Rotating-shift workers and people working more than 60 hours a week need to be particularly careful.
  • Commercial drivers, especially long-haul drivers. At least 15 percent of all heavy truck crashes involve fatigued driving.
  • People with undiagnosed or untreated disorders. People with untreated obstructive sleep apnea have been shown to have up to a 7 times higher risk of falling asleep at the wheel.
  • Business travelers, who spend many hours driving or may be jet-lagged.

The NSF suggests that a driver may be at-risk if they are sleep-deprived and/or if they are:

  • Driving a long distance without proper rest breaks. Schedule a regular break every two hours or every 100 miles.
  • Driving through the night, or driving during a time when the driver would normally be asleep. Crashes tend to occur at times when, according to the driver’s circadian rhythms, sleepiness is most pronounced, for example, from midnight to 6 a.m., and in the mid-afternoon.
  • Taking sedating medications such as cold tablets, antihistamines or anti-depressants.
  • Drinking any amount of alcohol, which is a depressant.
  • Driving alone or on a long, rural, dark or boring road.

The above driving situations should be avoided, if at all possible. It is best to stop driving altogether if you feel drowsy or exhibit signs of fatigue.

The AAA Foundation offers these warning signs of drowsy driving:

  • The inability to recall the last few miles traveled.
  • Having disconnected or wandering thoughts.
  • Having difficulty focusing or keeping your eyes open.
  • Feeling as though your head is very heavy.
  • Drifting out of your driving lane, perhaps driving across the rumble strips.
  • Yawning repeatedly.
  • Accidentally tailgating other vehicles.
  • Missing traffic signs.

The AAA Foundation also says that more than half of drivers involved in fatigue-related crashes experienced no symptoms before falling asleep behind the wheel. The Foundation says that drivers should make it a priority to get the proper amount of sleep each night rather than relying on their bodies to tell them when they are too sleepy to drive.

As Peter Kissinger, president and CEO of the AAA Foundation for Traffic Safety, said in a 2014 news release, “Despite the fact that 95 percent of Americans deem it unacceptable to drive when they are so tired that they have a hard time keeping their eyes open, more than 28 percent admit to doing so in the last month.”

Recommended Hours of Sleep for Drivers by Age Group

In 2015, the National Sleep Foundation (NSF) issued new recommendations for appropriate sleep durations, which included wider appropriate sleep ranges for most age groups.

Charles A. Czeisler, PhD, MD, chairman of the board of the National Sleep Foundation and professor of Sleep Medicine at the Harvard Medical School, said it was the first time that any professional organization has developed age-specific recommended sleep durations based on a systematic review of scientific literature relating sleep duration to health, performance and safety.

A summary of the new recommendations includes these sleep needs for people of age to drive:

  • Teenagers (14-17): Sleep range widened by one hour to 8-10 hours (previously it was 8.5-9.5)
  • Younger adults (18-25): Sleep range is 7-9 hours (new age category)
  • Adults (26-64): Sleep range did not change and remains 7-9 hours
  • Older adults (65+): Sleep range is 7-8 hours (new age category).

For younger people, the NSF recommends:

  • Newborns (0-3 months): Sleep range narrowed to 14-17 hours each day (previously it was 12-18)
  • Infants (4-11 months): Sleep range widened two hours to 12-15 hours (previously it was 14-15)
  • Toddlers (1-2 years): Sleep range widened by one hour to 11-14 hours (previously it was 12-14)
  • Preschoolers (3-5): Sleep range widened by one hour to 10-13 hours (previously it was 11-13)
  • School-age children (6-13): Sleep range widened by one hour to 9-11 hours (previously it was 10-11).

The NHTSA says if you start to get sleepy while you’re driving, drinking one or two cups of coffee and pulling over in a safe place for a short 20-minute nap, such as a lighted designated rest stop, may be helpful. This has been shown in scientific studies to increase alertness, but only for short periods of time.

Coffee or energy drinks might help you feel more alert, the NHTSA says, but the effects last only a short time. You may not really be as alert as you think you are. If you consume caffeine but are seriously sleep-deprived, you still may have “micro sleeps” or brief losses of consciousness that can last for 4 or 5 seconds. This means that at 55 miles per hour, you could travel more than 100 yards down the road while asleep. That’s plenty of distance to cause a crash.

Michael Kelly Injury Lawyers Helps People Harmed by Drowsy Drivers in Boston

The Boston personal injury attorneys at Michael Kelly Injury Lawyers work with individuals and families who have been injured or lost loved ones in car accidents caused by fatigued or drowsy drivers. We help the victims of at-fault drivers seek compensation for their losses due to injuries, property damage, lost income while recovering, and more.

If a driver has made the poor decision to drive while impaired or deprived of adequate sleep, the driver has put other motorists in harm’s way and should be held accountable if he or she causes a serious wreck. Our Boston car accident attorneys will investigate your car accident attributed to fatigued driving, and seek justice for the injured.

Contact Michael Kelly Injury Lawyers in Boston to set up a free legal consultation about pursuing a fatigued driving accident claim. Our firm’s guarantee is that, if within the first 30 days you are unhappy for any reason with our legal services, we will return your case file with no charges to you.

Call us today for professional and aggressive legal representation in your fatigued driving car accident claim..

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Michael D. Kelly has a diverse background that provides a breadth of legal knowledge that he draws upon in serving his clients. Kelly compiled an excellent academic record during his three years at New England Law in Boston.