The dangers of texting while driving gets more headlines and drunk driving remains one of the main causes of automobile accidents, but a large, new study published Monday helps explain why so many teens and young adults are involved in motor accidents.

Indiana State Police/AP

Motor Carrier Inspector Master Trooper Mike Probasco, left, looks over the remains of a box truck with its driver Dagoberto Perez, of Cicero, Ill. in November 2010. Perez, who said he fell asleep and veered off the road, was cited for being a fatigued driver. Both drivers received non-life threatening injuries.

They're sleepy.

Report after report shows it -- sleepy drivers cause car crashes. In the new study, researchers at The George Institute for Global Health in Sydney, Australia suggest that a long-term lack of sleep may not only cause immediate drowsiness at the wheel, but may affect a young driver’s judgment over time.

“Less sleep per night significantly increased the risk for crash for young drivers,” the researchers wrote in the American Medical Association journal JAMA Pediatrics.

Alexandra Martiniuk and colleagues studied the driving records of more than 19,000 young men and women, aged 17 to 24, who had just received their driver’s licenses. These new drivers had filled out questionnaires that included specific details about how many hours sleep they got each night in the previous month.

Then the researchers went through police records on road crashes for the next two years after the drivers were licensed.

 “Those who reported sleeping six or fewer hours per night had an increased risk for crash compared with those who reported sleeping more than six hours,” they wrote. The people who slept the least were 21 percent more likely to have been involved in a crash than those who got more sleep, Martiniuk’s team found.

On the weekends, the risk rose even more. Those who got six hours or less sleep on the weekend were 55 percent more likely to be in a crash than those who slept more.

It’s a global problem affecting not only young drivers, they noted. “For drivers of all ages, estimates in the United States, United Kingdom, and Australia report that between 5 percent and 30 percent of crashes are attributed to fatigue,” the researchers noted. “Not only are they more likely to have sleep-related crashes; these crashes are more likely to be fatal compared with other crash causes.”

 The AAA Foundation published a survey last year that found one in seven licensed drivers ages 16-24 admits they had fallen sleep at least once while driving in the past year and that 10 percent of all drivers say they’ve dozed off at the wheel. The Centers for Disease Control and Prevention found that 5 percent of adults aged 18 to 44 admitted to nodding off at the wheel.

One in six crashes with a fatality was caused by a drowsy driver, according to the National Highway Traffic Safety Administration (NHTSA).

The NHTSA says sleepy driving is involved in 100,000 crashes serious enough to generate a police report each year. Such crashes have killed more than 1,500 Americans and injured 71,000.

Sabrina Birch was one of those victims. According to the Daily Oklahoman and other media reports, Birch, 17, was thrown out of the pickup truck when her boyfriend, Colby Ruthardt, also 17, fell asleep at the wheel and crashed last November.  The Gracemont, Okla. teen died from her injuries.

Martiniuk’s team found some suggestion that a lack of sleep may affect other behaviors, too.

“Risky driving, sensation seeking, self harm ... and greater drug and alcohol intake were reported more often by individuals who obtained less sleep,” they reported. It’s not clear whether a lack of sleep was a cause or a symptom, but they said the finding  points the way to doctors, parents and others trying to help.

They also noted direct measures that can help prevent crashes caused by sleepy drivers. “Changes to road design (eg, tactile road edges and divided highways), as well as education campaigns, may help reduce crash risk,” they wrote.

“Using a rest stop, drinking coffee, and playing the radio while driving have been shown to be significantly protective against crashes, at least in the short term,” they added.

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• The dangers of drowsy teen drivers

Federal health regulators say an experimental insomnia drug from Merck can help patients fall asleep, but it also carries worrisome side effects, including daytime drowsiness and suicidal thinking.

The Food and Drug Administration on Monday released its review of the company's sleep aid, suvorexant, ahead of a public meeting on Wednesday. The pill works by temporarily blocking chemical messengers that keep people awake.

The FDA said company trials show suvorexant is better than placebo at helping people fall asleep and stay asleep. And regulators said the drug's effectiveness was consistent across several doses tested by Merck & Co. Inc.

But patients taking the higher doses of the drug showed an eight-fold increase in daytime drowsiness, which sometimes interfered with driving the next morning. Patients taking 20 milligrams and 40 milligrams of suvorexant had trouble staying in their driving lanes when tested by company researchers. FDA notes that four women actually had to stop the driving test due to excessive sleepiness.

The FDA review also notes that suvorexant was associated with increased risk of suicidal thinking. Over 12 months, there were eight cases of suicidal thinking or behavior reported among patients taking the drug, compared with no cases among patients given placebo.

Merck has proposed a starting dose of 15 milligrams for seniors and 20 milligrams for non-seniors. Doctors would gradually raise these doses to 30 milligrams and 40 milligrams, respectively, or until the patient's insomnia has been successfully treated.

On Wednesday the FDA will ask a panel of outside experts to vote on questions of the drug's safety and effectiveness. The agency appears to favor eliminating most of the higher doses of the drug tested by Merck.

The FDA says Merck data suggest that a 10 milligram dose may be safer, while still being effective.

"Indeed, if a dosage strength lower than 15 milligrams is unavailable, we would need to consider if the drug could be marketed safely at all, if we believe that a substantial proportion of the indicated population needs a lower dose," the agency states in its review.

The agency plans to ask its advisers whether there is enough data to support a 10 milligram dose, according to draft questions posted online.

ISI Group analyst Mark Schoenebaum called the FDA's review "tough."

"The high dose is deemed unsafe, and the FDA wonders if there is enough data at the safer low dose to draw firm safety conclusions," Schoenebaum said in a note to investors. He says it could take Merck 18 months to resubmit its drug, if FDA requires another study of low-dose suvorexant. The potential impact on Merck's revenue is relatively small, since the drug is only expected to generate peak sales of $650 million by 2018.

In January, the FDA required drugmakers of Ambien and similar sleeping pills to lower the dosage of their drugs, based on studies suggesting a link to drowsiness-related injuries. The agency cited research showing that the drugs remain in the bloodstream at levels high enough to interfere with driving.

"If I'm on the road, I'd be a little worried about the other drivers," said the study's lead author, Anne Wheaton of the Centers for Disease Control and Prevention.

In the CDC study released Thursday, about 4 percent of U.S. adults said they nodded off or fell asleep at least once while driving in the previous month. Some earlier studies reached a similar conclusion, but the CDC telephone survey of 147,000 adults was far larger. It was conducted in 19 states and the District of Columbia in 2009 and 2010.

CDC researchers found drowsy driving was more common in men, people ages 25 to 34, those who averaged less than six hours of sleep each night, and — for some unexplained reason — Texans.

Wheaton said it's possible the Texas survey sample included larger numbers of sleep-deprived young adults or apnea-suffering overweight people.

Most of the CDC findings are not surprising to those who study this problem.

"A lot of people are getting insufficient sleep," said Dr. Gregory Belenky, director of Washington State University's Sleep and Performance Research Center in Spokane.

The government estimates that about 3 percent of fatal traffic crashes involve drowsy drivers, but other estimates have put that number as high as 33 percent.

Warning signs of drowsy driving: Feeling very tired, not remembering the last mile or two, or drifting onto rumble strips on the side of the road. That signals a driver should get off the road and rest, Wheaton said.

Even a brief moment nodding off can be extremely dangerous, she noted. At 60 mph, a single second translates to speeding along for 88 feet — the length of two school buses.

To prevent drowsy driving, health officials recommend getting 7 to 9 hours of sleep each night, treating any sleep disorders and not drinking alcohol before getting behind the wheel.

By Kerry Grens
Reuters.com

While parents may sometimes despair of their children getting enough shut-eye, especially with age-old stalling tactics of another story or another glass of water, children in the United States do appear to be getting the recommended amount of sleep.

According to a U.S. study published in the Archives of Pediatric and Adolescent Medicine, there has been concern that U.S. children are getting too little sleep, with insufficient sleep tied to issues ranging from behavior problems to heart health risks.

But there hasn't been much hard evidence on how much sleep children typically get, so a group led by Jessica Williams, a graduate student at the University of California Los Angeles, set out to get estimates of sleep times from birth to age 18.

"These estimates are consistent with the amount of sleep recommended for children, and no evidence was found of racial/ethnic differences," the group wrote in its report.

The researchers gathered data from a nationwide survey that has tracked families for decades, focusing on parents' reports of their children's sleep, beginning in 1997.

At that time, 2,832 children were included, In 2002 and 2007 the families were surveyed again and 2,520 and 1,424 children were included, respectively.

Williams's team found that until their second birthday, babies in the study slept an average of 12 to 14 hours during each 24-hour period.

By age four it had dropped to about 11 hours of sleep and by age 10, to 10 hours. By age 16, kids were getting an average of about nine hours of sleep per night.

The U.S. Centers for Disease Control and Prevention recommends that toddlers get 12 to 14 hours of sleep, preschoolers 11 to 13 hours, and adolescents aged 10 to 17 from 8.5 to 9.5 hours.

One of the big strengths of this study is that it tracked changes in sleep among the same children as they aged, said Maurice Ohayon, director of the Stanford Sleep Epidemiology Research Center in Palo Alto, California.

"We have an evolution of the sleep during the childhood. That is the unique thing," said Ohayon, who was not involved in the study.

The researchers didn't find any differences in the amount of sleep between boys and girls, and only a slight gap between white and Hispanic children.

Hispanic kids tended to sleep 19 minutes longer than white children after age nine, but Williams said that difference is too small to matter for individual kids.

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Too few hours of sleep can raise the risk of stroke significantly, even among healthy, normal-weight people, a new study finds.

Attention, busy middle-aged folks. You may be healthy and thin, but if you habitually sleep less than six hours a night, you still could be boosting your risk of a stroke.

That’s the surprising conclusion of a new study being presented Monday at SLEEP 2012, the annual meeting of the nation’s sleep experts.

Getting too little shut-eye appeared to more than quadruple the risk of stroke symptoms among healthy, normal-weight people aged 45 and older, according to a study of some 5,600 people followed for up to three years.

“The really important take-home message is this: Don’t blow it off. Sleep is just as important as diet and exercise,” said Megan Ruiter, the University of Alabama at Birmingham researcher who led the study.

Experts recommend that healthy adults get between seven and nine hours of sleep a night. But about one in three U.S. workers regularly gets less than seven hours of snooze time, according to a recent government health report.

Ruiter and her colleagues reviewed data from some 30,239 people participating in the REGARDS study – Reasons for Geographic and Racial Differences in Stroke – sponsored by the National Institutes of Health.

Of those, they teased out some 5,666 people who were healthy at the start of the study – no history of stroke, stroke symptoms, so-called “mini-stroke” or transient ischemic attack, or elevated risk for sleep apnea and other sleep-disordered breathing problems.

“We eliminated all the people who were high risk,” Ruiter said.

But when they looked more closely at the sleep habits of those people and adjusted for their weight, they found what Ruiter said were unexpected results.

In people who fell into normal weight categories -- a body mass index of 18.5 to nearly 25 -- those who reported sleeping less than six hours a night were at about 4.5 times greater risk of developing stroke symptoms than whose who slept seven and eight hours a night. Surprisingly, that increase wasn't apparent in overweight or obese people who slept less.

“Our thought is that habitually sleeping less than six hours is kind of like a precursor,” said Ruiter. “It might kind of lead to some of these stronger and more severe risk factors later on.”

That’s dismaying news to Mark Wolfe, 49, a busy teacher, husband and father of four from Corvallis, Ore., who has run the Boston Marathon eight times and routinely gets six hours of sleep or less, waking at 4:05 a.m. on weekdays in order to train.

“Because I’m leading a very active and healthy life, I don’t expect to drop dead from a stroke,” said Wolfe, who is tall and thin, with a BMI of about 21.  

But there’s no question, adults function best with more sleep than six hours a night, experts say. Chronic sleep deprivation caused by getting too little most nights may boost the risk of stroke because it causes changes in the autonomic functions of the body, including blood pressure, heart rate, inflammation and glucose levels, said Dr. Phyllis C. Zee, associate director for Sleep & Circadian Biology at the Northwestern University School of Medicine.

“It not only affects the blood vessels to the heart and body, but also to the brain,” said Zee, who was not involved in the study presented at the meeting of the Associated Professional Sleep Societies.

It will take more research to determine whether short sleep actually results in more full-blown strokes for the REGARDS participants. But in the meantime, Ruiter said the study offers cautions for Wolfe and other middle-aged people who maintain their weight but scrimp on sleep.

“The important thing now is just to have physicians and people be more aware that the amount and quality of sleep might be important for how they feel and the quality of their health,” she said.

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• One-third of US workers don't get enough sleep
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By MyHealthNewsDaily staff

People with sleep apnea — disordered breathing while they slumber — are more likely to develop cancer or to die from it than people with no breathing problems, two new studies suggest.

Those who had severe sleep apnea were found to be nearly five times more likely to die from cancer over the 22-year period of one of the studies.

In the other study, people with apnea had an increased risk of developing any type of cancer, and those with the most severe apnea had the greatest risk.

The new findings seem to agree with studies in animals that show tumor growth is promoted by an inadequate supply of oxygen.

The studies found only an association — they do not suggest sleep apnea causes cancer or contributes to its growth, the researchers said. But if future studies confirm the results, diagnosis and treatment of sleep apnea in patients with cancer might prolong their survival, said study researcher F. Javier Nieto, of the University of Wisconsin-Madison School of Medicine and Public Health.

The studies were presented this week at an American Thoracic Society meeting in San Francisco.

Previous studies have linked sleep apnea with increased risks of high blood pressure, heart disease, depression, and early death from any cause. The condition is characterized by pauses in breathing or shallow breathes during sleep, according to the National Institutes of Health. Such pauses can last for seconds to minutes, and often occur five to 30 times or more an hour. At least 1 in 10 people older than 65 has sleep apnea, the NIH says.

In the study of cancer mortality rates, Nieto and colleagues analyzed information from 1,522 Wisconsin residents who enrolled in a sleep study in 1989. Every four years, the participants underwent a polysomnography test — an all-night recording of their sleep and breathing — along with other medical tests.

The worse the participants' sleep apnea was, the more likely they were to die from cancer during the 22-year study period, the researchers said. Participants with severe sleep apnea were 4.8 times more likely to die than those with sleep breathing problems. The link was stronger among non-obese people than obese people.

The results held even after the researchers took into account factors that could affect a person's risk of death from cancer, including age, sex, body mass index (BMI) and smoking.

In the other study, researchers in Spain gathered data on 5,246 patients who were diagnosed with sleep apnea in seven Spanish hospitals between 2000 and 2007, and found that 5.7 percent of them developed some type of cancer during the study period.

In a separate study, also presented at the meeting, researchers from Spain found that the link between an inadequate supply of oxygen and increased cancer growth was stronger in lean mice than in obese mice.

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This, finally, may explain our cultural obsession with zombies: Long after dark, millions of Americans basically become one.

Without warning, they suddenly rise from their silent, supine states then roam aimlessly, eyes open and mouths sputtering gibberish.

About 8.5 million U.S. adults -- or 3.6 percent of the grownup population -- have taken at least one sleepwalking jaunt during the past year, according to research released today by the Stanford University School of Medicine. That figure, calculated via a survey of nearly 20,000 people, means there are far more nocturnal wanderers than scientists previously suspected.

“It’s something, we were thinking, that was not frequent among the general population. And here, big surprise, it is,” said Dr. Maurice Ohayon, professor of psychiatry and behavioral sciences at Stanford and lead author of the paper. A previous report done a decade ago in European adults showed that 2 percent of that population were sleepwalkers. “It’s astonishing.”

The finding offers American doctors their first, solid sleepwalking benchmark, Ohayon said. Earlier speculation on how often the phenomenon occurred were based on anecdotal clinical reports as well as court cases and media tales of people who had gone sleep-driving, sleep-shopping or sleep-eating. Typically, those more sensational examples were linked to Ambien use.

But Ohayon and his colleagues found no significant link between prescription sleeping pills and increased sleepwalking. What they did discover: Folks who take certain anti-depressants (selective serotonin reuptake inhibitors, or SSRIs) are three times more likely to also take a snoozy stroll than the general population, and people who swallow over-the-counter sleeping pills have a higher likelihood of experiencing sleepwalking episodes at least twice a month month.

Brand names for anti-depressants in the SSRI category include Prozac, Zoloft, Paxil, Lexapro and Celexa. Non-prescription sleep aids linked to increased sleepwalking by the Stanford team contained diphenhydramine. Products laced with that chemical include 40 Winks, Simply Sleep, Sleep-Eze, Sominex, Unisom Sleep, Advil PM, and Tylenol PM, according to the National Institutes of Health. 

Chronic sleepwalking also runs (rambles?) within certain families, Ohayon learned: Nearly one-third of individuals who often do it can point to parents, grandparents, uncles, aunts or siblings who have a history of shuffling while slumbering.

To assess the sleepwalking rate in America, Ohayon and his Stanford colleagues used phone interviews conducted with 19,136 randomly selected individuals from 15 states. The participants offered baseline information on their mental health, medical histories and use of medications. They were quizzed on the frequency of any sleepwalking episodes as well as whether they had ever suffered any inappropriate or possibly perilous behaviors while asleep.

What's more, participants were asked if they'd sleepwalked when they were kids and if any family members were known to take unintended, nighttime strolls. In addition to the more more than 3 percent of the U.S. population who sleepwalk chronically, the researchers found that 29.2 percent of the test sample had gone sleepwalking at least once during their lives. 

photaigraphy

Robert Budd, a personal trainer from Southern California, takes sleeping strolls about once a month, as do almost all the men in his family.

Personal trainer Robert Budd figures he sleepwalks about once a month. When he gathers with his kin, sleepwalking lore is a common topic: while seemingly in dreamland, his grandfather once urinated in a friend’s drawer, his uncle often meandered the decks of navy boats, and his dad dismantled tents and ceiling fans.

“All the boys in the family do it,” said Budd, who operates a gym called PHYZYKS in Encinitas, Calif. “I've done it since I was a kid. I would walk out the door and my parents had to grab me and get be back inside. The commonality with my family and myself is it seems to happen when we’re really tired, really drained. When you really need sleep, that’s when you get up and sleepwalk.”

Budd has sleepwalked out of a tent at the Grand Canyon (on the floor, not near the rim). His friends spotted him heading off alone -- apparently wide awake -- but he remembered nothing the next day. While dozing, he once packed for a vacation, even remembering his toothbrush. And there was the night he tried to climb out a second-floor window only to be stopped by the woman who is now his ex-wife.

Was that intended exit possibly symbolic, even for a sleeping man? “It might have been,” Budd said with a laugh.

“It drives my girlfriend drives nuts because sometimes we have conversations and she doesn’t know if I’m awake. Like, I can’t be accountable in the middle of the night.”

Sleepwalkers typically have their eyes open and may speak, making detection tricky. But Ohayon isn’t certain, he said, if they are actually seeing what’s in front of them or if sleepwalkers’ brains have simply mapped out their homes in their minds, allowing them not to bump into walls or furniture. He is sure they’re not dreaming, though, because sleepwalking coincides with a period of “slow-wave sleep” or SWS when brain activity is diminished.

During another sleep phase called REM (rapid eye movement), brain neurons are firing as if a person is awake. This is when you dream. A mechanism within the brain blocks stirring and shifting when you’re in REM sleep, Ohayon said.

“During slow wave sleep, you can move,” he added. “This is an old function of our brain, (possibly a evolutionary leftover). You know, when birds fly, they can sleep with one half of their brain, while the other half is analyzing the flight.

“That is why you see the bird going for thousand of kilometers without any problem. They sleep when they fly.”

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Nearly a third of workers in the U.S. aren't getting enough sleep, according to a new government report.

Overall, 30 percent of employed U.S. adults reported getting less than six hours of sleep a night, the Centers for Disease Control and Prevention said in its report. The National Sleep Foundation recommends that healthy adults get seven to nine hours of sleep.

People who usually work the night shift — especially those in transportation, warehousing, health care and social assistance industries — were more likely than day-shift workers to report not getting enough sleep. Forty-four percent of the night shift workers participating in the survey said they got less than six hours of sleep, compared with 29 percent of workers with day shifts.

"Insufficient sleep can have serious and sometimes fatal consequences for fatigued workers and others around them," the CDC wrote. An estimated 20 percent of vehicle crashes are linked to drowsy driving.

Besides poor job performance, too little sleep has been linked with obesity and cardiovascular disease, the report noted.

Those with night jobs face a particular challenge in getting enough sleep. "Attempts to sleep during daylight hours, when melatonin levels decline and body temperature rises, usually result in shorter sleep episodes and more wakefulness," the report said.

Companies should implement ways to improve workers' chances for enough sleep, the report said. For example, training programs on sleep and working hours can be tailored for managers and employees, and work shifts can be designed in ways to improve sleep opportunities.

The reports of sleep-deprived workers varied by industry, with manufacturing faring among the worst. The CDC said 34.1 percent of manufacturing workers reported not getting enough sleep.

When the results were broken down by age group, the findings showed people in the middle of their working years were most likely to report less than six hours of sleep a night: about 32 percent of people between the ages of 30 and 64, compared with 26.5 percent of those ages 18-29, and 21.7 percent of those 65 and older.

There were also differences among races. Black workers (38.9 percent), and Asian workers (33.2 percent) were significantly more likely to report short sleeps than white workers (28.6 percent) or Hispanic workers (28.8 percent), the report said.

People who were widowed, divorced, or separated were significantly more likely to report sleeping than six hours (36.4 percent) than with workers who were married (29.4 percent) or had never been married (28.2 percent).

The results are based on the data gathered during 2009 and 2010 in the National Health Interview Survey, for which a nationally representative sample of more than 15,000 adults were interviewed in their homes. The report was limited in that the data relied on people's own reports of how much sleep they get.

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