The Multiple Sleep Latency Test (MSLT) to measure sleepiness was done on 618 people. During the MSLT, every two hours the participant has an opportunity to nap, and EEG measures how long it takes to fall asleep. Falling asleep in 5- 10 minutes is considered moderately sleepy, with sleep onset in less than 5 minutes considered excessively sleepy. The number of car crashes in the 10 years surrounding the MSLT was tabulated for each person.
The people who were excessively sleepy had an accident rate of 59%, while those who were alert had only a 47% rate. The difference in number of accidents between these two groups was significant. Excessively sleepy people also had a higher risk of severe injury in an auto accident than alert individuals.
This is important for us as individuals every time we get on the road, and is also a public safety issue. Read earlier blogpost for tips you can use to stay alert on the road.
Several years ago I had a neighbor who worked odd hours. Sometimes she’d work in the day, sometimes leave for work at 4pm, and sometimes she’d be in her office for more than 24hrs. Our kitchen and dining room looked out onto her driveway and front door so we frequently saw her coming and going.
And thank goodness we could see her! Several times she pulled into her drive in the morning after being gone all night, and fell asleep right there in the car, with her head on the steering wheel and the engine running. We’d go and wake her when we noticed that the engine wasn’t turned off.
This is just one example of the dangers of drowsy driving. What would have happened if she’d fallen asleep on the road, or if nobody had been there to wake her up?
Planning ahead before driving will help you reduce your risk of drowsy driving. Get adequate sleep the night before. Try to travel long distances with a companion who can take turns driving and can help you stay alert with some good conversation. Plan enough time so you can take plenty of breaks – at least every 2 hours or 100 miles on long trips. Avoid alcohol and sedating medications while driving.
While you are driving if you are yawning, constantly blinking, or find your head nodding those are signs that you are drowsy. Mentally you may not remember driving the last few miles, you may feel irritable, or experience wandering, dream-like thoughts. You may drift in your lane or even hit the side rumble strip.
If you experience any of these symptoms Stop and Rest! Even a twenty minute nap can hold drowsiness off for a while. You can also use the alerting effects of caffeine. A good plan is to pull over, drink a caffeinated drink and take a 20 minute nap. Because it takes about 30 minutes to feel the effects of caffeine this plan will provide the benefits of both the nap and caffeine. (Be aware that caffeine is less effective in people who regularly drink a lot of it).
Although it is just the end of October, soon the winter holidays will be in full swing. Let’s help make this a happy holiday season for everyone by getting enough sleep to be a safe driver, and making other arrangements when those holiday festivities cut our sleep short!
Have you heard the buzz about drowsy driving? Sleep experts are now estimating that drowsy driving accounts for over 100,000 accidents each year, and causes 1550 deaths! The number of fatigue-related accidents may actually be much higher than this estimate because is it so difficult to detect. Fatigue-related accidents usually occur with a driver who is alone, driving at night, during the mid-afternoon lull, or at another time they are usually asleep. As opposed to a drunk driver, the drowsy driver will not swerve, apply the brakes or take any action to avoid the accident. They can’t, because they are asleep!
In 2005 the National Sleep Foundation conducted a large poll about drowsy driving. 60% of drivers said they had driven while drowsy, and an amazing 37% admitted to falling asleep at the wheel in the last year. Personally, these are alarming statistics to remember whenever I get on the road.
You are at risk if you have been awake for greater than 16 or 17 hours, are chronically sleep deprived, or have had a sleepless night. If you have an untreated sleep disorder such as sleep apnea you are also at risk. Some groups are more at risk than others, including men aged 25 and younger, shift workers, commercial drivers, business travelers, those who drive at night, and anyone who has worked 60 hours in a week.
Next Monday’s blog post will be filled with strategies to avoid drowsy driving, so check back then.