Study Finds Less Brain Gray Matter in Men with Sleep Apnea

A new study reports that men with severe obstructive sleep apnea have less brain gray matter. This may help explain the cognitive problems that often occur in people with OSA.

The results were published in the Feb. 1 issue of the journal Sleep.

The South Korean study involved 36 men with severe OSA. They had an average of 52.5 partial and complete breathing pauses per hour of sleep. Their average age was 44.7 years. They were compared with 31 healthy, male, age-matched controls.

Brain scans were conducted using magnetic resonance imaging (MRI). A processing technique called “optimized voxel-based morphometry” found structural differences in gray matter by examining the entire brain.

Results show significant differences between men with severe OSA and healthy controls. Gray matter concentrations were decreased in multiple brain areas of men with OSA.

“Poor sleep quality and progressive brain damage induced by OSA could be responsible for poor memory, emotional problems, decreased cognitive functioning and increased cardiovascular disturbances,” study co-author Dr. Seung Bong Hong told the AASM.

The NINDS reports that “gray matter” refers to the cerebral cortex. This is where the brain does most of its information processing. The cortex is a layer of tissue with a gray-colored appearance.

The men in this study were newly diagnosed and untreated. Dr. Hong said that they could benefit greatly from treatment with CPAP therapy.

“The use of continuous positive airway pressure – CPAP - therapy could stop further progression of brain damage in patients with severe OSA,” said Hong.

Last year the Sleep Education Blog reported that CPAP therapy may help restore a normal pattern of brain activation. Other studies have provided more evidence that untreated sleep apnea causes brain damage.

Are you at risk for sleep apnea? STOP and find out. You also can answer these questions on SleepEducation.com to learn more about your risk. Get help for sleep apnea at an AASM-accredited sleep center near you.

Read more about sleep and the brain.

You May Need Less Sleep as You Get Older

A new study suggests that healthy older adults without sleep disorders may have a reduced "sleep need." The results were published in the Feb. 1 issue of the journal Sleep.

The U.K. study involved 110 healthy adults. They had no sleep disorders or sleep complaints. Their sleep was evaluated during an overnight sleep study.

Results show that total sleep time decreased with age. Older adults between 66 and 83 years of age slept about 20 minutes less than middle-aged adults and about 43 minutes less than young adults.

The study also found that the sleep of older adults was more fragmented and less intense. Awakenings during the night increased. And time spent in deep, slow-wave sleep decreased.

But it was younger adults who were sleepiest during the day. Older adults took longer to fall asleep during a daytime nap study.

"Our findings reaffirm the theory that it is not normal for older people to be sleepy during the daytime," lead author Derk-Jan Dijk, PhD, told the AASM. "If you are sleepy during the day you either don't get enough sleep or you may suffer from a sleep disorder."

In a 2008 study Dijk reported on the age-related reduction in the “maximal capacity for sleep.” Adults were allowed extended periods of sleep to determine their sleep need. The total daily sleep time of older adults (7.4 hours) ended up being 1.5 hours less than that of younger adults (8.9 hours).

It is unclear what may cause a change in the sleep need of older adults. The authors suggested that alterations in reproductive hormones or changes in the brain may be involved.

They added that the study did not address sleepiness during the evening hours. At that time of day older adults may be sleepier than young adults.

The authors also wrote that the results may help explain why some healthy older adults struggle with insomnia. They may be unaware of their reduced sleep need.

So insomnia may occur because they spend too much time in bed. “Sleep restriction” may help get their sleep back on track. This is one form of cognitive-behavioral therapy.

But it is important to note that many older adults have insomnia due to a medical condition. And they may have insomnia as a side effect of a medication.

Read more about sleep and older adults.

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Child Symptoms of ADHD & Sleep Loss Can Be Confused

Australian pediatric sleep expert Dr. Chris Seton recently told the Sydney Morning-Herald that it is very possible to confuse symptoms of ADHD with the effects of sleep deprivation in children.

“A tired five-year-old and a five-year-old with ADHD can both act in the same way," he said. "There's probably a common pathway, but so far researchers have been unable to find what it is."

Last year the Sleep Education Blog reported that children respond to sleep loss in a different way than adults. Sleep-deprived adults tend to be sleepy and sluggish during the day. But sleep-deprived children are often hyperactive.

What could be keeping your child from getting enough sleep? Typically, a combination of biological, social and educational factors.

Recently the Sleep Education Blog reported that children and teens between 8 and 18 years old spend more than 7.5 hours a day watching TV and using electronic devices like cell phones and computers.

Homework, extracurricular activities and time with friends also often cut into sleep time.

Sleep deprivation is linked with behavioral problems and mood disorders in children. Students who are not getting the sleep they need also tend to do worse in school.

How do parents know if their child is sleep deprived? Seton said that a child who can wake up in the morning without an alarm clock is probably getting enough sleep.

ADHD is a serious condition that affects a large number of children. And sleep deprivation is a common alternative explanation for a child’s misconduct. You may want to monitor your child’s sleep habits if you notice changes in his or her behavior.

The AASM recommends that school-aged children sleep between nine and 10 hours each night.

Parents should enforce bedtimes and a nightly routine to help their children get an adequate amount of sleep each night. Sleep experts also recommend keeping the TV and other electronics out of the bedroom.

Learn more about sleep and children. Get help for a sleep problem at an AASM-accredited sleep center near you.

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How Much Sleep Do I Need?

UCLA researcher Jerry Siegel addressed this common question earlier in the week.

What’s the answer? One sleep size doesn’t fit all.

“Some people naturally sleep six hours,” he wrote. “And others naturally sleep eight hours.”

The better question is: Do you get enough sleep to remain alert and attentive during the day? And are you able to go to sleep and wake up without using alcohol, caffeine or other drugs?

If so, then you’re probably getting enough sleep.

But he warns that persistent daytime sleepiness is one sign that you may have a sleep disorder. And you should talk to a doctor if you have loud and frequent snoring. This is a common symptom of obstructive sleep apnea.

Last year an editorial by Siegel explored the nature and role of sleep.

Get help for an ongoing sleep problem at an AASM-accredited sleep center near you.

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Chronic Insomnia: Less Brain Gray Matter in Older Adults

A new study from The Netherlands examined regional brain volume in people with insomnia.

The study involved 24 adults with chronic primary insomnia. They were between the ages of 52 and 74 years. Seventeen of them were women. They were compared with 13 people who had no sleep problems.

Results show that people with insomnia had a smaller volume of gray matter in the left orbitofrontal cortex. This reduction in gray matter was strongly correlated with the severity of insomnia.

The NINDS reports that “gray matter” refers to the cerebral cortex. This is where the brain does most of its information processing. The cortex is a layer of tissue with a gray-colored appearance.

The study also found reduced gray matter volume in the precuneus. This cortical area may have a central role in tasks such as episodic memory retrieval.

A press release noted that the affected brain regions play a role in evaluating pleasure. They also have a role in the brain’s “resting state.”

Most people with insomnia have “secondary” insomnia. It occurs along with another medical problem, mental illness or sleep disorder. It also may result from the use of a medication or substance. In contrast primary insomnia is unrelated to another health problem.

A 2008 study in the journal Sleep linked primary insomnia to low levels of a brain chemical. Results show that GABA levels are reduced by 30 percent in adults with chronic primary insomnia.

Last year a study proposed that “cooling the brain” may be a new way to treat insomnia. Subjective benefits were reported by 75 percent of participants.

Read more about insomnia. Get help for an ongoing sleep problem at an AASM-accredited sleep center near you.