Archive for the 'Sleep Disorder News' Category

Loss of sleep, even for a few short hours during the night, can prompt one’s immune system to turn against healthy tissue and organs.

A new article reports that losing sleep for even part of one night can trigger the key cellular pathway that produces tissue-damaging inflammation.

The findings suggest a good night’s sleep can ease the risk of both heart disease and autoimmune disorders such as rheumatoid arthritis.

Specifically, the researchers measured the levels of nuclear factor (NF)-κB, a transcription factor that serves a vital role in the body’s inflammatory signaling, in healthy adults.

These measurements were repeatedly assessed, including in the morning after baseline (or normal) sleep, after partial sleep deprivation (where the volunteers were awake from 11 pm to 3:00 am), and after recovery sleep.

In the morning after sleep loss, they discovered that activation of (NF)-κB signaling was significantly greater than after baseline or recovery sleep. It’s important to note that they found this increase in inflammatory response in only the female subjects.

These data close an important gap in understanding the cellular mechanisms by which sleep loss enhances inflammatory biology in humans, with implications for understanding the association between sleep disturbance and risk of a wide spectrum of medical conditions including cardiovascular disease, arthritis, diabetes, certain cancers, and obesity.

Sleep tends to help people better remember aspects of a negative event while allowing memory of background information to fade, researchers have found.

The brain “seems to make adaptive ‘decisions’ about what to remember and what to forget,” Dr. Jessica D. Payne of Beth Israel Deaconess Medical Center and Harvard Medical School in Boston, Massachusetts, told. This suggests the sleeping brain does more than simply consolidate whatever one puts into it, Payne said.

Payne and colleagues enlisted 88 college students to participate in recall tests after seeing pictures that depicted either neutral subjects on a neutral background (a normal car parked on a street in front of shops) or negatively arousing subjects on a neutral background (a badly crashed car parked on a similar street).

The participants were then tested separately on their memories of both the central objects in the pictures and the backgrounds in the scenes.

Some of the students viewed the pictures in the morning and took memory recall tests 12 hours later after a full day and no napping.

Others viewed the pictures at night, slept for 12 hours, and completed memory recall tests in the morning, while a third group of students viewed the pictures either in the morning or the evening and completed recall tests 30 minutes later.

Teenagers are notorious for having bad sleep habits. New research suggests that having trouble staying awake the next day might not be the only consequence they face.

In the first study to look at the relationship between not getting enough sleep and blood pressure in healthy adolescents, researchers found that healthy teens (ages 13 to 16 years old) who slept less than 6.5 hours a night were 2.5 times more likely to have elevated blood pressure compared to those who slept longer.

In addition, those with poor sleep, or low sleep efficiency – having trouble falling asleep or staying asleep – had, on average, 4 mm Hg higher systolic blood pressure (the top number) and were 3.5 times more likely to have prehypertension or hypertension than their peers who slept well.

Untreated high blood pressure can increase the risk for stroke and other cardiovascular diseases later in life.

The findings are from a cross-sectional analysis of 238 adolescents ages 13 to 16 years old (average age of 14) enrolled in the Cleveland Children’s Sleep and Health Study.

Sleep efficiency and duration was evaluated at home for three to seven nights, where teens completed a daily sleep log and wore a wrist device that measures movement to determine sleep and wake cycles.

Studies have shown that children and teens who fail to get the proper amount of sleep each night are more prone to obesity, and researchers now think it may be linked to a particular stage of sleep.

They said not spending enough time in rapid eye movement, or REM, sleep — the type that is normally associated with dreaming — significantly increased the odds of obesity in children and teens.

“Our results demonstrated that the short sleep-obesity association may be attributed to reduced REM sleep,” said Dr. Xianchen Liu of Western Psychiatric Institute and Clinic in Pittsburgh reported on Monday in the Archives of General Psychiatry.

Ultimately, obesity is the byproduct of taking in more calories than the body needs. But Liu and colleagues wanted to see if they could identify any stage of sleep that appeared especially important.

The researchers studied 335 children and adolescents aged 7 to 17 for three consecutive nights. Their sleep was monitored through polysomnography, which measures sleep cycles and stages by recording brain waves, electrical activity of muscles, eye movement, breathing rate, blood pressure, and other variables.

Aging impairs the consolidation of memories during sleep, a process important in converting new memories into long-term ones, according to new animal research in the July 30 issue of The Journal of Neuroscience.

The findings shed light on normal memory mechanisms and how they are disrupted by aging.

During sleep, the hippocampus, a brain region important in learning and memory, repeatedly “replays” brain activity from recent awake experiences.

This replay process is believed to be important for memory consolidation. In the new study, Carol Barnes, PhD, and colleagues at the University of Arizona found reduced replay activity during sleep in old compared to young rats, and rats with the least replay activity performed the worst in tests of spatial memory.

Barnes and colleagues recorded hippocampal activity in 11 young and 11 old rats as they navigated several mazes for food rewards. Later, when the animals were asleep, the researchers recorded their hippocampal activity again.

In the young animals, the sequence of neural activity recorded while the animals navigated the mazes was repeated when they slept. However, in most of the old animals, the sequence of neural activity recorded during sleep did not reflect the sequence of brain activity recorded in the maze.

Research has found that men who suffer sleepless nights run double the risk of contracting diabetes.

The link with Type 2 diabetes, the most common form, held firm even when factors such as weight, smoking and exercise were taken into account.

Researchers from the Karolinska Institute in Sweden tracked the health of more than 5,000 middle-aged men and women for up to ten years.

The volunteers, none of whom had diabetes at the start, filled in questionnaires about levels of stress. They were told symptoms included insomnia, apathy, anxiety and fatigue.

Analysis showed that the most stressed-out men were more than twice as likely to develop Type 2 diabetes.

It is thought stress may raise the risk of diabetes by disrupting the production of hormones. People worn out by lack of sleep may also be less likely to exercise.

The link applied only to men, the journal Diabetic Medicine reports, possibly because they bottle up their feelings more than women.

Going for a stroll can help keep Type 2 diabetes under control, a Newcastle University study found. Walking an extra 45 minutes a day helps stabilize blood sugar levels, the Diabetes UK-funded research showed.

Old people are known to be lousy sleepers, but a new study suggests it might all be in their heads, at least for many of them.

Medications, poor health, bad bedtime habits (such as watching a movie or drinking coffee or booze), circadian rhythms, and too much or too little in their personal “sleep bank” have all taken the blame for seniors’ common complaints of insomnia.

Elizabeth Klerman of Brigham and Women’s Hospital and the Harvard Medical School set out to clear it up once and for all with a controlled study of 18 subjects ages 60 to 76 and 35 younger subjects, ages 18 to 32, all healthy and not on medication that might affect sleep.

Even people who had crossed more than one time zone in the past 3 months were disqualified, as well as those who had worked night or rotating shifts in the past three years.

After monitoring their sleep at home, the subjects were regularly instructed to lie quietly with their eyes closed and to try to sleep, for as much as 16 hours daily for several days in a row. They had all the time in the world.

It’s not necessarily laziness that makes people hit the “snooze” button in the morning.

Most likely, your body clock is mismatched with the demands of your life.

Your clock is controlled by the suprachiasmatic nucleus, a part of the brain that controls the body’s biological rhythms.

But, says Jean Matheson, a sleep-disorders specialist, these preset natural rhythms often don’t align with daily realities—work or school start times cannot be adjusted to fit a person’s sleep schedule.

People who have trouble crawling out of bed probably have an inner clock set to late wake-up and sleep times, a condition known as phase delay.

It is possible to adjust your phase-delayed body clock, Matheson says, but at a price: No sleeping in on the weekends.

“When people sleep late on weekends, they revert to their natural phase-delayed rhythm,” she explains. This makes it harder to wake up early on weekdays. You can train yourself to wake up earlier, Matheson says, by setting your alarm 15 minutes earlier each day.

Exposure to artificial light in the evening can also cause phase delay. The brain is very sensitive to light, and too much of it just before bed—from computer screens, televisions or bright reading lights—can trick the brain into thinking it’s daytime.