Sleepiness is such a potent biological signal that regardless of how well motivated, trained or professional an individual may be, the brain can and will initiate sleep. Up to 3% of all highway crashes -- and about 4% of all fatal crashes -- are due to driver sleepiness. These figures may be underestimates studies of sleepy behavior in drivers suggest that sleepiness may be a more common cause of highway crashes than is reflected in these estimates.
Sleepiness -- the blunted alertness that accompanies insufficient or inadequate sleep -- impairs vigilance and coordination, and slows reaction time and decision making, the authors note. Since driving makes demands on these abilities, sleepy drivers are at high risk on the road.
People with sleep disorders such as sleep apnea, narcolepsy, and chronic insomnia are at particularly high risk of sleep-related traffic accidents. A variety of factors can contribute to insomnia, including medical problems, stress, and certain drugs.
Young drivers also run a higher risk of sleep-related accidents -- often because demands of school, work, and extra curricular activities keep them from getting sufficient sleep. Working the night shift or a rotating shift can also increase risk, because it throws the body's biological clock out of sync and interferes with restful sleep. Not surprisingly, truck drivers who work late at night, or work long irregular schedules, are at high risk.
Finally, drinking and taking illegal and some legal drugs can bring on and intensify sleepiness, boosting the risk of sleep-related traffic accidents. Prescription and over-the-counter sleeping pills, opioid analgesics, tricyclic antidepressants, antipsychotics, and certain high blood pressure drugs and muscle relaxants can all cause sleepiness, the researchers note.
To lower the odds of getting into sleep-related accidents, the authors suggest that drivers:
- get adequate sleep before a trip.
- avoid alcohol and other sedating drugs.
- avoid driving between midnight and 6 AM -- the hours the biological clock is usually set for sleep.
- see a doctor if daytime sleepiness is a problem.
Drivers who feel sleepy while driving often try opening the window to let in cold air, listening to the radio, or taking a brief exercise break -- but these measures are of only "marginal benefit" in the fight to stay awake, the researchers say. Drinking coffee or other drinks that contain caffeine, or taking a brief nap, can be more effective, but are still no replacement for sleep.
The Journal of the American Medical Association June 17, 1998;279:1908-1913.
COMMENT: The only way to reverse the physiological need for sleep is to sleep. Sleep is one of the essential elements of an optimal wellness program. If you are depressed, sleeping is generally impaired and the tryptophan and or a good exercise program will help in this area. Most of us though stay up far too late. There are many who turn on the TV and forgo necessary sleep. If this is your situation, I would advise against turning the TV on when you get home from work. It is just too strong of a temptation to not watch once it is on. I also strongly advise getting a minimum of six hours and preferably 8 hours of sleep every night.