The Dangers of Drowsiness
Sleep-deprived people often don't realize their vulnerability to sleepiness, and therein rests the self-denial, explains Joseph Kaplan, MD, co-director of the Sleep Disorders Center at the Mayo Clinic in Jacksonville, Fla.
"Sleepiness is governed by two processes - the amount of sleep you get and the circadian rhythm," he tells WebMD. "You can go a night without sleep, and be fairly alert the next morning. But as the circadian influence begins to have its impact, that's when you really feel it."
Kaplan says the most vulnerable times for sleepiness: 5 to 8 a.m. and 2 to 4 p.m. Most alert times: 10 a.m. to noon and 7 to 9 p.m. "Regardless how many hours you're awake, the sleepiest time occurs as the circadian night is ending," he says.
Night shift workers may be the hardest hit by sleep problems. They're less able to stay alert, they have decreased job performance, and they have more accidents. One study found that 20% of shift workers fall asleep during a single night shift compared to none during an afternoon or evening shift.
Several major disasters have been linked in part with too little sleep in the workplace: Three Mile Island, Chernobyl, and the Exxon Valdez.
Nearly one-third of all respondents to the 2008 Sleep in America poll reported that they have driven drowsy at least once per month during the past year. Of those who drive, more than one-third had nodded off or fallen asleep while driving a vehicle. And 2% had an accident or near accident due to drowsiness while driving.
"We are very concerned that shift workers are on the highway, at increased risk for car wrecks," says Barbara Phillips, MD, sleep clinic director at the University of Kentucky in Lexington. "Many are also in safety-sensitive positions, like health care workers and pilots."
Indeed, doctors, nurses, and other health professionals are especially vulnerable to the effects of sleep loss - and patient safety may suffer because of it. Studies on performance of sleep-deprived doctors have suggested that they may be prone to more errors on routine, repetitive tasks - and also on tasks that require close attention for long periods. However, those same studies show that, in times of crisis or unusual situations, doctors may be able to rise to the occasion and function well.