Showing posts with label jet lag. Show all posts
Showing posts with label jet lag. Show all posts

Wednesday, March 11, 2015

How to avoid issues from Daylight Savings Time

With Daylight Savings on March 8th, we will lose an hour of sleep. This article explains why it may be an issue for people and gives tips on how to avoid any problems.

You may find you feel a little more tired than usual next month as you adjust to the start of Daylight Saving Time, which begins at 2 a.m on Sunday, March 8.
“An hour seems like a minor change, but moving the clock ahead one hour can be very stressful or disruptive for some people, particularly for those who are already sleep deprived,” says to Jeffrey P. Barasch, M.D., FACCP, FAASM, Medical Director of The Valley Hospital Center for Sleep Medicine.
“The problem goes beyond just the loss of a single hour of sleep on the night of the clock change,” Dr. Barasch says, “The time change also plays havoc with the body’s circadian rhythm, or biological clock.”
This biological clock, located within a part of the brain behind the eyes, determines when we feel alert and when we are sleepy. The internal clock keeps our bodies synchronized with the daily light-dark cycle of the outside world. The biologic clock is ‘set’ or fixed to the time of day by two factors: the time we regularly wake up in the morning and our exposure to sunlight during the day. It can be reset, but (as anyone who has traveled by airplane across several time zones has experienced), the biological clock cannot be adjusted too quickly.

When we move the time clock one hour earlier for daylight savings time, our bodies remain partly on the prior schedule (known as ‘jetlag’ in plane travel). The result: 7 am in daylight savings time is equivalent to 6 a.m. standard time. Also, your typically sunlit mornings will now be dark, and that lack of morning light makes it even more difficult for your internal clock to adjust. So not only are we losing an hour of sleep, but since it can take some time to readjust, we’re left feeling tired for more than the one day on which the clocks change.

People who normally sleep well can usually adjust to the time shift with relatively little difficulty. However, if someone has been barely coping with an undiagnosed and untreated sleep disorder, daylight saving time can exacerbate and therefore unmask problems such as sleep apnea, insomnia or periodic limb movement disorder.

The following tips from Dr. Barasch can help you get a good night’s sleep:
• On the nights after the time change, go to bed at your usual time. You may experience some difficulty falling asleep, because your body’s clock has not yet adjusted.
• Get up at your usual time regularly. Although you may find this a bit difficult, it will help you adjust to the time change.
• Avoid sunlight or bright light in the first few evenings after the time change, as this will tend to keep you awake later and prevent adjustment of your body’s clock.
• Try to get sunlight exposure soon after awakening in the first few mornings after the time change, as this will help you adjust to the new time.
• A short nap can help make up for less sleep, but won’t help you acclimate to the new schedule. Don’t nap within a few hours of your regular bedtime to avoid disrupting nighttime sleep.
• Create a sleep-friendly environment that is dark, cool, comfortable and quiet.
• Have a relaxing routine before bedtime, such as soaking in a hot bath, reading or listening to soothing music.
• Avoid caffeine, nicotine and alcohol for several hours prior to bedtime, as they can disrupt sleep.

If you regularly experience daytime drowsiness, fatigue or disturbed sleep, speak to your doctor or consult with a sleep medicine specialist.

Read more here

Thursday, September 04, 2014

Confused arousal associated with behavioral issues

Confused arousal or "sleep drunkenness," which is waking up in a state of confusion, is linked to other behavioral issues.

"Sleep drunkenness" is more common than previously thought, affecting about one in seven Americans, or 15 percent, according to a new study that looked at the sleeping habits of more than 19,000 adults.
Also called confusional arousal, the condition causes people to wake up in a confused state, not knowing where they are. In the most severe cases, they can injure themselves or others, explained lead researcher Dr. Maurice Ohayon, a professor of psychiatry at Stanford University School of Medicine.
"There was a case of a man on a ship who awoke in a confused state and fell off the deck to his death," Ohayon said.
In addition to such extreme cases, there have been cases where waking up in a confused state led to the person striking a bedmate. Most people can't remember the incident afterwards.
Ohayon noted that these episodes can occur even while taking a nap. "This happens to most people occasionally, like when you are jet-lagged," he said. The difference is that these episodes are frequent among those who suffer from confusional arousal, he noted.
Treatment for confusional arousal hinges on treating the other sleep problems patients have, Ohayon said. When these problems are treated, the condition often disappears.
Whether sleep drunkenness is its own condition or a symptom of other sleep problems is an ongoing debate, Ohayon noted.
The report was published in the Aug. 26 issue of the journal Neurology.
Dr. David Rye, a professor of neurology at Emory University in Atlanta, said, "Confusional arousals exist -- and are probably more common than we thought."
But, he added, "As in most epidemiological surveys, what is reported are associations, not causes and effects."
For the study, researchers interviewed more than 19,000 people aged 18 and older about their sleep habits and if they had experienced any symptoms of confusional arousal. They were also asked whether they had been diagnosed with a mental illness and about the medications they took.
The researchers found that 15 percent of the participants had a confusional arousal episode in the last year. Over half of those people said they had more than one episode per week.
In most cases -- 84 percent -- the study participants said in addition to sleep drunkenness, they had other sleep disorders, a mental health disorder or used psychotropic medications such as antidepressants. Less than 1 percent of those with sleep drunkenness didn't have another sleep problem, the researchers found.
Among those suffering from confusional arousal, 37 percent also had a mental health problem. Those with depression, bipolar disorder, alcoholism, panic or post-traumatic stress disorder and anxiety tended to be more likely to also have sleep drunkenness, the study authors noted.
Sleep drunkenness was also associated with sleeping too little or too much. About 20 percent of those who slept less than six hours a night and 15 percent of those who slept at least nine hours suffered from sleep drunkenness, the investigators found. In addition, people with sleep apnea were also more likely to have the problem.
Rye doesn't think the study pinpoints the most common problems associated with sleep drunkenness.
Confusional arousal is poorly defined, he said. "We need to know more about how to define and recognize those with the problem, how it negatively impacts patients' lives, how large is the unmet clinical need, and determine whether a doc should care about the complaint," Rye said.
Dr. Scott Krakower, assistant unit chief of psychiatry at Zucker Hillside Hospital in Glen Oaks, N.Y., said, "Many patients and doctors are not aware of what confusional arousals are. They can often be misinterpreted for other neurologic and psychiatric conditions."
Krakower noted that it is important to treat the underlying medical problem to avoid confusional arousals.
"In addition, staying on a proper sleep regimen is very important to prevent these premature arousals," he said.
Read more here

Thursday, January 30, 2014

Sleeping during the day can hurt your genes

This study shows that sleeping during the day can mess up a third or a person's genes.

Sleeping during the day -- a necessity for jet-lagged travelers and those who work overnight shifts -- disrupts the rhythms of about one-third of your genes, a new study suggests.
What's more, shifted sleep appears to disrupt gene activity even more than not getting enough sleep, according to the research.
For the new study, which was published in this week's issue of the journal Proceedings of the National Academy of Sciences, British researchers put 22 healthy, young volunteers in a dimly lit sleep lab for three days.
During the first day, they disrupted the participants' sleep at regular intervals to reset their body clock to its innate rhythm. On the second and third days, the volunteers ate and slept on a 28-hour schedule, so their longest period of sleep was from noon until about 6:30 p.m.
The researchers drew blood samples all three days so they could watch what happened to the timing of gene activity.
During the first day, when the body reset its circadian rhythm, nearly 1,400 genes -- about 6.4 percent of all genes that were analyzed -- were in sync with that rhythm. On the days of shifted sleep, however, the number of genes tied to the body's clock dropped dramatically, to 228 genes, or only 1 percent of genes analyzed.
The researchers estimated that the sleep disruptions would ultimately impact about a third of a person's genes.
That's an even greater disruption than scientists saw in a previous study when they tested the effects of sleep deprivation on gene activity. In that study, which had study volunteers sleeping about five and half hours each night, the number of genes that were in sync with the body's clock dropped from about 9 percent to 7 percent.
"These are quite fundamental processes that are being affected," said senior study author Derk-Jan Dijk, a professor of sleep and physiology at the University of Surrey, in the United Kingdom.
"We think that may be related to the negative health outcomes associated with long-term shift work," Dijk said. Shift workers are at higher risk for many health problems, including obesity, diabetes, high blood pressure, heart disease, disrupted menstrual cycles and cancer, he said.
This study didn't directly connect health problems and night-shift work, but experts said it does start to help them understand why sleep might have such a powerful influence on a person's health.
"This study suggests that mistimed sleep can alter circadian rhythms, so the cycling of many, many genes is impaired," said Dr. Mark Wu, assistant professor of neurology, medicine, genetic medicine and neuroscience at Johns Hopkins University. "What this could cause, they can't really say -- except it's probably not good." Wu was not involved in the new research.
Genes carry the instructions for making proteins. Proteins make up just about every kind of chemical signal, hormone and tissue in the body, the researchers said.
The timing of when proteins are made is important because their production should correspond to our behaviors, said Frank Scheer, a neuroscientist at Harvard and director of the Medical Chronobiology Program at Brigham and Women's Hospital in Boston.
When the body anticipates a meal, for example, the liver has to stop releasing into the blood the carbohydrates it has stored and the pancreas has to make more insulin, while the muscles have to become more sensitive to insulin that's released so they can take in blood sugar, Scheer said.
"If these processes are working in concert and they're synchronized to when you eat and when you fast, then the system is very efficient and effective at absorbing these sugars quickly and minimizing any adverse consequences of elevated blood sugar levels," Scheer said.
"If these are not rhythmic, then you can easily imagine that, during the nighttime, you have this machinery up and running without need," he said. "During the daytime, when you actually do need it, it's only running half speed."
Read more here

Sunday, September 01, 2013

Understanding jet lag may help develop drugs to help with time zone changes

A study using jet lagged mice helps researchers determine what makes people slow to adjust to jet lag and may help develop medication to make the transition easier.

New research in mice reveals why the body is so slow to recover from jet lag and identifies a target for the development of drugs that could help us to adjust faster to changes in time zone.
With funding from the Wellcome Trust and F. Hoffmann La Roche, researchers at the University of Oxford, University of Notre Dame and F. Hoffmann La Roche have identified a mechanism that limits the ability of the body clock to adjust to changes in patterns of light and dark. And the team show that if you block the activity of this gene in mice, they recover faster from disturbances in their daily light/dark cycle that were designed to simulate jet-lag.
Nearly all life on Earth has an internal circadian body clock that keeps us ticking on a 24-hour cycle, synchronising a variety of bodily functions such as sleeping and eating with the cycle of light and dark in a solar day. When we travel to a different time zone our body clock eventually adjusts to the local time. However this can take up to one day for every hour the clock is shifted, resulting in several days of fatigue and discombobulation.
In mammals, the circadian clock is controlled by an area of the brain called the suprachiasmatic nuclei (SCN) which pulls every cell in the body into the same biological rhythm. It receives information from a specialised system in the eyes, separate from the mechanisms we use to 'see', which senses the time of day by detecting environmental light, synchronising the clock to local time. Until now, little was known about the molecular mechanisms of how light affects activity in the SCN to 'tune' the clock and why it takes so long to adjust when the light cycle changes.
To investigate this, the Oxford University team led by Dr Stuart Peirson and Professor Russell Foster, used mice to examine the patterns of gene expression in the SCN following a pulse of light during the hours of darkness. They identified around 100 genes that were switched on in response to light, revealing a sequence of events that act to retune the circadian clock. Amongst these, they identified one molecule, SIK1, that terminates this response, acting as a brake to limit the effects of light on the clock. When they blocked the activity of SIK1, the mice adjusted faster to changes in light cycle.
Dr Peirson explains: "We've identified a system that actively prevents the body clock from re-adjusting. If you think about, it makes sense to have a buffering mechanism in place to provide some stability to the clock. The clock needs to be sure that it is getting a reliable signal, and if the signal occurs at the same time over several days it probably has biological relevance. But it is this same buffering mechanism that slows down our ability to adjust to a new time zone and causes jet lag."
Disruptions in the circadian system have been linked to chronic diseases including cancer, diabetes, and heart disease, as well as weakened immunity to infections and impaired cognition. More recently, researchers are uncovering that circadian disturbances are a common feature of several mental illnesses, including schizophrenia and bipolar disorder.
Russell Foster, Director of the recently established Oxford University Sleep and Circadian Neuroscience Institute supported by the Wellcome Trust, said: "We're still several years away from a cure for jet-lag but understanding the mechanisms that generate and regulate our circadian clock gives us targets to develop drugs to help bring our bodies in tune with the solar cycle.Such drugs could potentially have broader therapeutic value for people with mental health issues."
Read more here

Wednesday, August 28, 2013

Jet lagged mice used to study sleep disorders

A study using jet lagged mice helped researchers study different sleep disorders.

Many factors keep us from getting a good night’s sleep. Prime culprits include overnight flights across the ocean, graveyard shifts, and stress-induced insomnia. A new study from McGill and Concordia Universities gives hope, however, that these common sleep disturbances may one day be put to bed.
The Earth’s rotation is responsible for creating day and night, and the daily rhythms of all living beings. Mammals have a “circadian clock” in their brains that drive the daily rhythms in sleep and wakefulness, feeding and metabolism, and many other essential processes. Until now, however, the inner workings and molecular processes of this complex brain clock have eluded scientists.
The findings, published in Neuron, identify how a fundamental biological process called protein synthesis is controlled within the body’s circadian clock. The researchers hope their work will help shed light on future treatments for disorders triggered by circadian clock dysfunction, including jet lag, shift work disorders, and chronic conditions like depression and Parkinson’s disease.
“To understand and treat the causes and symptoms of circadian abnormalities, we have to take a closer look at the fundamental biological mechanisms that control our internal clocks,” says Dr. Shimon Amir, professor in Concordia University’s Department of Psychology.
Amir worked with Dr. Nahum Sonenberg, a James McGill professor in the Dept. of Biochemistry, Faculty of Medicine, at the Goodman Cancer Research Centre at McGill University, to study how protein synthesis is controlled in the brain clock. “We identified a repressor protein in the clock and found that by removing this protein, the brain clock function was surprisingly improved,” explains Dr. Sonenberg.
The circadian clocks of all mammals are similar, so the team was able to use mice to conduct their experiments. The mouse model used lacked this specific protein, known as 4E-BP1. The protein blocks the important function of protein synthesis. The mice that lacked this protein were able to overcome disruptions to their circadian clocks more quickly, the team found.
“In modern society, with the frequency of trans-time zone travel, we often deal with annoying jet lag problems, which usually require a couple of weeks of transition,” says Dr.Ruifeng Cao, a postdoctoral fellow who works with Drs. Sonenberg and Amir, “However, by inducing a state like jet lag in the mice lacking that protein, we found they were able to adapt to time zones changes in about half of the time required by regular mice.”
The research team also found, in mice lacking the protein 4E-BP1,there was a small increase in another small protein necessary for brain clock function, vasoactive intestinal peptide or VIP. This indicates to the researchers the functioning of the circadian clock could be improved by genetic manipulations, opening doors on new ways to treat circadian clock-related disorders.
“A stronger clock function may help improve many physiological processes, such as aging,” says Cao. “In addition, understanding the molecular mechanisms of biological clocks may contribute to the development of time-managing drugs,” Amir concurs, noting that “the more we know about these mechanisms, the better able we will be to solve problems associated with disruptions to our bodies’ internal clocks”.
Read more here

Sunday, December 30, 2012

Excess holiday eating has same effect as jet lag

This article discusses how excess holiday eating disturbs your "food clock" and has effects similar to jet lag or working the graveyard overnight shift at work. It also discusses how to reset your "food clock."

If the sinful excess of holiday eating sends your system into butter-slathered, brandy-soaked overload, you are not alone: People who are jet-lagged, people who work graveyard shifts and plain-old late-night snackers know just how you feel.

All these activities upset the body's "food clock," a collection of interacting genes and molecules known technically as the food-entrainable oscillator, which keeps the human body on a metabolic even keel. A new study by researchers at the University of California, San Francisco (UCSF) is helping to reveal how this clock works on a molecular level.
Published this month in the journalProceedings of the National Academy of Sciences, the UCSF team has shown that a protein called PKCγ is critical in resetting the food clock if our eating habits change.
The study showed that normal laboratory mice given food only during their regular sleeping hours will adjust their food clock over time and begin to wake up from their slumber, and run around in anticipation of their new mealtime. But mice lacking the PKCγ gene are not able to respond to changes in their meal time -- instead sleeping right through it.
The work has implications for understanding the molecular basis of diabetes, obesity and other metabolic syndromes because a desynchronized food clock may serve as part of the pathology underlying these disorders, said Louis Ptacek, MD, the John C. Coleman Distinguished Professor of Neurology at UCSF and a Howard Hughes Medical Institute Investigator.
It may also help explain why night owls are more likely to be obese than morning larks, Ptacek said.
"Understanding the molecular mechanism of how eating at the "wrong" time of the day desynchronizes the clocks in our body can facilitate the development of better treatments for disorders associated with night-eating syndrome, shift work and jet lag," he added.
Resetting the Food Clock
Look behind the face of a mechanical clock and you will see a dizzying array of cogs, flywheels, reciprocating counterbalances and other moving parts. Biological clocks are equally complex, composed of multiple interacting genes that turn on or off in an orchestrated way to keep time during the day.
In most organisms, biological clockworks are governed by a master clock, referred to as the "circadian oscillator," which keeps track of time and coordinates our biological processes with the rhythm of a 24-hour cycle of day and night.
Life forms as diverse as humans, mice and mustard greens all possess such master clocks. And in the last decade or so, scientists have uncovered many of their inner workings, uncovering many of the genes whose cycles are tied to the clock and discovering how in mammals it is controlled by a tiny spot in the brain known as the "superchiasmatic nucleus."
Scientists also know that in addition to the master clock, our bodies have other clocks operating in parallel throughout the day. One of these is the food clock, which is not tied to one specific spot in the brain but rather multiple sites throughout the body.
The food clock is there to help our bodies make the most of our nutritional intake. It controls genes that help in everything from the absorption of nutrients in our digestive tract to their dispersal through the bloodstream, and it is designed to anticipate our eating patterns. Even before we eat a meal, our bodies begin to turn on some of these genes and turn off others, preparing for the burst of sustenance -- which is why we feel the pangs of hunger just as the lunch hour arrives.
Scientist have known that the food clock can be reset over time if an organism changes its eating patterns, eating to excess or at odd times, since the timing of the food clock is pegged to feeding during the prime foraging and hunting hours in the day. But until now, very little was known about how the food clock works on a genetic level.
Read more here