Automobile Accidents & Drowsiness

Drowsiness can cause an accident.

In a Sleep in America poll conducted by the National Sleep Foundation in 2005, an astonishing 60 percent of Americans reported operating a vehicle while feeling drowsy, while 37 percent of drivers fell asleep at the wheel. A total of 13 percent report dosing off at least once a month while driving, according to Drowsy Driving. An unavoidable need for sleep causes drowsiness, resulting in significantly delayed reaction times and accidents.

Sleep Deprivation

Drowsiness is a direct result of sleep deprivation. The National Highway Safety Traffic Administration (NHSTA) states that 7 to 9 hours of sleep each night is necessary for ultimate performance. The NHSTA also reports that people who lose 1 to 2 hours of sleep per night generally take two full nights of sleep to catch up and return to normal functioning.

Medical Conditions

Medical conditions are also to blame for drowsiness at the wheel. Often, sleep disorders such as sleep apnea and narcolepsy go untreated or unnoticed--both conditions increase the risk of automobile crashes due to drowsiness. Some medication is known to increase drowsiness--sedating antihistamines, benzodiazepine anxiolytics, long-acting hypnotics and tricyclic antidepressants. Illegal drug use can also cause drowsiness and accidents.

Most at Risk

The NHSTA reports that young people between the ages of 16 and 29 are most likely to become drowsy and fall asleep while driving. Males are five times more at risk than females in sleep-related crashes, according to NHSTA. Drivers who begin work at midnight possess the greatest risk of sleep disruption because of daytime sleeping conditions. Hospital workers such as nurses, hospital interns and residents, who consistently work 12 hours or longer while remaining on call, report a large number of sleep-related driving problems. The NHSTA states that 95 percent of nurses who work a 12-hour shift report having a close call or sleep-related crash. Twenty-five percent of hospital interns and residents, who may work 24 hours or more, report being in an accident, 40 percent of which occurred after a long shift on-call.

Statistics

The NHSTA reports accidents relating from sleep deprivation are more likely to include serious injuries and fatalities. The drowsy driver typically drives on high-speed roads with speed limits between 55 to 65 mph. Most accidents involve a single car straying off the road. Considering delayed reaction times from sleepiness, most drowsy-driving related crash reports state a lack of brake lights, skid marks or evidence of corrective driving behavior. The driver does not attempt to avoid the crash. Accidents are most likely to occur during late night hours.

Alcohol Use

The NHSTA states that combined drowsiness and alcohol use can increase the effect of alcohol impairment. This combination of the two is more impairing than sleepiness or alcohol use alone. Even a driver who ingests alcohol below the legal driving limit is more likely to deviate from the road after 4 hours of sleep than after 8 hours of sleep, according to NHSTA.

References

• Drowsy Driving: Facts and Stats
• NHTSA: Drowsy Driving and Automobile Crashes