Don’t worry, be happy: Just go to bed earlier
December 4, 2014
http://images.sciencedaily.com/2014/12/141204091129-large.jpg
Science Daily/Springer Science+Business Media
Researchers link late evenings to repetitive negative thoughts. When you go to bed, and how long you sleep at a time, might actually make it difficult for you to stop worrying. So say researchers, who found that people who sleep for shorter periods of time and go to bed very late at night are often overwhelmed with more negative thoughts than those who keep more regular sleeping hours.
People are said to have repetitive negative thinking when they have bothersome pessimistic thoughts that seem to repeat in their minds. They feel as though they have little control over these contemplations. They also tend to worry excessively about the future, delve too much into the past, and experience annoying intrusive thoughts.
Such thoughts are often typical of people suffering from generalized anxiety disorder, major depressive disorder, post-traumatic stress disorder, obsessive compulsive disorder, and social anxiety disorder. These individuals also tend to have sleep problems.
Previous studies have linked sleep problems with such repetitive negative thoughts, especially in cases where someone does not get enough shut eye. Nota and Coles set out to replicate these studies, and to further see if there's any link between having such repetitive thoughts and the actual time when someone goes to bed.
"Making sure that sleep is obtained during the right time of day may be an inexpensive and easily disseminable intervention for individuals who are bothered by intrusive thoughts," remarks Nota.
The findings also suggest that sleep disruption may be linked to the development of repetitive negative thinking. Nota and Coles therefore believe that it might benefit people who are at risk of developing a disorder characterized by such intrusive thoughts to focus on getting enough sleep.
"If further findings support the relation between sleep timing and repetitive negative thinking, this could one day lead to a new avenue for treatment of individuals with internalizing disorders," adds Coles. "Studying the relation between reductions in sleep duration and psychopathology has already demonstrated that focusing on sleep in the clinic also leads to reductions in symptoms of psychopathology."
http://www.sciencedaily.com/releases/2014/12/141204091129.htm
Suicide risk linked to insomnia, alcohol use
December 22, 2014
Science Daily/American Academy of Sleep Medicine
Insomnia symptoms mediate the relationship between alcohol use and suicide risk, and that this mediation is moderated by gender, a new study demonstrates for the first time. The study suggests that the targeted assessment and treatment of specific sleep problems may reduce the risk of suicide among those who use alcohol.
The study found that alcohol use was significantly associated with suicide risk among women. However, further analysis revealed that insomnia symptoms explained a significant proportion of the relationship between alcohol and suicide risk. For men, there was no direct effect of alcohol use on suicide risk, but there was a significant indirect effect of alcohol use increasing suicide risk through insomnia symptoms.
"These results are important as they help demonstrate that alcohol use is associated with an increase in suicide risk, and that this increase may be partially due to insomnia symptoms," said principal investigator Michael Nadorff, PhD, assistant professor at Mississippi State University in Starkville, Miss. "By better understanding this relationship, and the mechanisms associated with increased risk, we can better design interventions to reduce suicide risk."
According to the American Academy of Sleep Medicine, about 10 percent of people have chronic insomnia disorder, which involves a sleep disturbance and associated daytime symptoms that have been present for at least three months. About 15 to 20 percent of adults have short-term insomnia disorder. Both types of insomnia are more common in women than in men.
http://www.sciencedaily.com/releases/2014/12/141222131358.htm
Light-emitting e-readers before bedtime can adversely impact sleep
December 22, 2014
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Science Daily/Brigham and Women's Hospital
Use of a light-emitting electronic device (LE-eBook) in the hours before bedtime can adversely impact overall health, alertness, and the circadian clock which synchronizes the daily rhythm of sleep to external environmental time cues, according to new research that compared the biological effects of reading an LE-eBook compared to a printed book.
"We found the body's natural circadian rhythms were interrupted by the short-wavelength enriched light, otherwise known as blue light, from these electronic devices," said Anne-Marie Chang, PhD, corresponding author, and associate neuroscientist in BWH's Division of Sleep and Circadian Disorders.
"Participants reading an LE-eBook took longer to fall asleep and had reduced evening sleepiness, reduced melatonin secretion, later timing of their circadian clock and reduced next-morning alertness than when reading a printed book."
Previous research has shown that blue light suppresses melatonin, impacts the circadian clock and increase alertness, but little was known about the effects of this popular technology on sleep. The use of light emitting devices immediately before bedtime is a concern because of the extremely powerful effect that light has on the body's natural sleep/wake pattern, and may thereby play a role in perpetuating sleep deficiency.
"In the past 50 years, there has been a decline in average sleep duration and quality," stated Charles Czeisler, PhD, MD, FRCP, chief, BWH Division of Sleep and Circadian Disorders. "Since more people are choosing electronic devices for reading, communication and entertainment, particularly children and adolescents who already experience significant sleep loss, epidemiological research evaluating the long-term consequences of these devices on health and safety is urgently needed."
http://www.sciencedaily.com/releases/2014/12/141222131348.htm
Stress can be a factor for developing diabetes, autoimmune diseases
January 2, 2015
Science Daily/Investigación y Desarrollo
Recurring stress can trigger insulin resistance, hypertension, abdominal fat deposition, researchers say.
Stress is an ability of humans to fight or flee when faced with problems affecting the individual. By changes in the organism, adaptation to various physical conditions is achieved: burns, bruises, bleeding or psychosocial traumas.
Is the route by which the body tries to solve a problem, but when the situation becomes recurrent, stress can trigger diseases such as diabetes, depression, insulin resistance, hypertension, abdominal fat deposition and other autoimmune diseases, said Siegfried Miracle Lopez, chief of endocrinology at the Advanced Immunology Center in Hospital Angeles Lomas.
Type II diabetes is a disease caused by a systemic imbalance. The body is in a constant state called homeostasis, in which a balance between the external medium variants like the weather, temperature, light, night and internal factors as blood pressure, heart rate, performance of the kidney, liver, pancreas and lungs.
When an imbalance of homeostasis and angiostasis arises, (alteration in immune and hormone systems) and the body can not adapt to it, this is when diseases are generated, in the case of type II diabetes the elevation of blood glucose is causing the stress.
It is very difficult to examine a disease without thinking that there is a mechanism that detonated it. By experiencing stress, homeostasis can be affected, especially if it is constant and is not giving the body time to re-adapt and reach a neutral point, this situation is what generates sufferings.
"Type II diabetes has immune, genetic and environmental components, is a multifactorial disease, thereby in medical schools we are no longer teaching diabetes as a disease but of a group of diseases characterized by glucose elevation, which causes inflammatory processes affecting the organs and immune system disorders that impair circulation, eyes and kidneys," explained the specialist.
For this reason, the chief of endocrinology at the institution, emphasized how a current problem is that doctors specialize in small parts of the body, because the organism is very complex, but a fragmented study may lead to misdiagnosis.
"The problem is wanting to stay in our micro universe specialty, missing the right diagnosis, hence arises the need for a multidisciplinary team together of several specialists such as neurologists, endocrinologists, urologists, psychologists, rheumatologists, oncologists , otolaryngologist, to analyze the case at the same time and achieve a better diagnosis and treatment," concluded Miracle Lopez.
http://www.sciencedaily.com/releases/2015/01/150102071555.htm
Rotating night shift work can be hazardous to your health
January 5, 2015
Science Daily/Elsevier
Night shift work has been consistently associated with higher risk for cardiovascular disease (CVD) and cancer. In 2007 the World Health Organization classified night shift work as a probable carcinogen due to circadian disruption.
In a new study, researchers found that women working rotating night shifts for five or more years appeared to have a modest increase in all-cause and CVD mortality and those working 15 or more years of rotating night shift work appeared to have a modest increase in lung cancer mortality. These results add to prior evidence of a potentially detrimental effect of rotating night shift work on health and longevity.
Sleep and the circadian system play an important role in cardiovascular health and antitumor activity. There is substantial biological evidence that night shift work enhances the development of cancer and CVD, and contributes to higher mortality.
An international team of researchers investigated possible links between rotating night shift work and all-cause, CVD, and cancer mortality in a study of almost 75,000 registered U.S. nurses. Using data from the Nurses' Health Study (NHS), the authors analyzed 22 years of follow-up and found that working rotating night shifts for more than five years was associated with an increase in all-cause and CVD mortality. Mortality from all causes appeared to be 11% higher for women with 6-14 or ≥15 years of rotating night shift work. CVD mortality appeared to be 19% and 23% higher for those groups, respectively. There was no association between rotating shift work and any cancer mortality, except for lung cancer in those who worked shift work for 15 or more years (25% higher risk).
The NHS, which is based at Brigham and Women's Hospital, began in 1976, with 121,700 U.S. female nurses aged 30-55 years, who have been followed up with biennial questionnaires. Night shift information was collected in 1988, at which time 85,197 nurses responded. After excluding women with pre-existing CVD or other than non-melanoma skin cancer, 74,862 women were included in this analysis. Defining rotating shift work as working at least three nights per month in addition to days or evenings in that month, respondents were asked how many years they had worked in this way. The prespecified categories were never, 1-2, 3-5, 6-9, 10-14, 15-19, 20-29, and ≥30 years.
According to Eva S. Schernhammer, MD, DrPH, currently Associate Professor of Medicine, Harvard Medical School, and Associate Epidemiologist, Department of Medicine, Brigham and Women's Hospital, Boston, this study "is one of the largest prospective cohort studies worldwide with a high proportion of rotating night shift workers and long follow-up time. A single occupation (nursing) provides more internal validity than a range of different occupational groups, where the association between shift work and disease outcomes could be confounded by occupational differences."
Comparing this work with previous studies, she continues, "These results add to prior evidence of a potentially detrimental relation of rotating night shift work and health and longevity...To derive practical implications for shift workers and their health, the role of duration and intensity of rotating night shift work and the interplay of shift schedules with individual traits (e.g., chronotype) warrant further exploration."
http://www.sciencedaily.com/releases/2015/01/150105081757.htm
International research effort gives neuroscientists better feeling about sense of touch
January 6, 2015
Science Daily/Carnegie Mellon University
Our sense of touch is one we often take for granted, until our leg falls asleep and we aren't able to stand, or when we experience acute pain. The sense of touch also has been taken for granted in neuroscience, where it's the sense scientists know the least about. For the first time, researchers have linked a group of neurons to a specific type of somatosensation, a finding that can open the door for a heightened understanding about our sense of touch.
"Somatosensation is critical. You can somewhat overcome losing your sense of smell, sight, taste, or hearing. But if you lose your sense of touch, you wouldn't be able to sit up or walk. You wouldn't be able to feel pain," said Barth, a professor of biological sciences and a member of Carnegie Mellon's BrainHubSM research initiative. "We know less about the features that make up our rich tactile experience than we do about any other sense, yet it's such a critical sense."
Somatosensation, which is another word for our sense of touch, occurs in a number of forms, like feeling texture, temperature, pressure, pain or vibration. It's responsible for proprioception, which helps us know where we are within our environment. It tells us if our feet are firmly planted on the floor, or if we're holding a paper cup tightly enough that it won't slip out of our hand, but loosely enough that we don't crush the cup. Scientists know a good deal about the molecular receptors that mediate the different types of somatosensation, but they know little about how touch is represented in the brain.
"When someone gets pricked by a pin, we know how information about that sensation travels from the skin to the spinal cord. But what happens in the brain has been much less clear -- it seems like all different sorts of touch information get jumbled together," said Barth, who also is a member of the joint Carnegie Mellon/University of Pittsburgh Center for the Neural Basis of Cognition (CNBC).
"This is the first time we've been able to visualize neurons in the somatosensory cortex that 'like' a specific tactile stimulus," Barth said. "It shows that neurons are individuals. They have different jobs to do in the cortex. In this case these neurons had a special feature: they responded when all of the mouse's whiskers moved at once."
They also found that the neurons in question received direct synaptic input from the posteromedial nucleus of the brain's thalamus. This shows that the neurons that react to the puff-of-air stimulus have a dedicated, unique sub-network of connections that enable them to communicate with one another and amplify the information they are receiving from the stimulus.
"Now that we have isolated the neural underpinnings of a certain feature, we can try to manipulate and change the interactions between cells. Can we train the mouse and strengthen the connections between neurons? What happens to perception if we remove the connections? It's really the frontier of truly understanding somatosensory function," Barth said.
This research also could lead to work that will identify how somatosensory information is coded, which could be used to incorporate sensory information into brain-machine interfaces. This could allow robotic limbs and prosthetics to actively sense and receive tactile input.
http://www.sciencedaily.com/releases/2015/01/150106095033.htm
Expressing anger linked with better health in some cultures
January 7, 2015
Science Daily/Association for Psychological Science
In the US and many Western countries, people are urged to manage feelings of anger or suffer its ill effects -- but new research with participants from the US and Japan suggests that anger may actually be linked with better, not worse, health in certain cultures.
"Many of us in Western societies naively believe that anger is bad for health, and beliefs like these appear to be bolstered by recent scientific findings," says psychological scientist Shinobu Kitayama of the University of Michigan. "But our study suggests that the truism linking anger to ill health may be valid only within the cultural boundary of the 'West,' where anger functions as an index of frustration, poverty, low status and everything else that potentially compromises health."
"These findings show how socio-cultural factors go under the skin to influence vital biological processes," explains Kitayama.
In other words, it's the circumstances that elicit anger, and not anger itself, that seem to be bad for health. In previous work, Kitayama and colleagues found that anger can function as a signal of high status and privilege in Asia -- drawing on this, they hypothesized that greater expression of anger might be associated with better health among Asian participants.
A recent incident on a Korean Air flight bound for Seoul illustrates this point, says Kitayama. Heather Cho, former vice president of Korean Air and daughter of Korean Air Chairman Cho Yang-ho, apparently flew into a rage when she was improperly served a bag of macadamia nuts by the chief flight attendant. In an angry outburst, Ms. Cho ordered the pilot to take the plane back to the gate so that the flight attendant could be kicked off the flight.
This expression of anger, which may seem disproportionate to the circumstance, is a typical display of privilege and power, says Kitayama, and may, therefore, be linked with better rather than worse health.
To explore the link, the researchers examined data from American participants drawn from the Midlife in the United States (MIDUS) survey and data from Japanese participants drawn from the Midlife in Japan (MIDJA) survey.
To measure health, the researchers looked at biomarkers for inflammation and cardiovascular functioning, both of which have been linked to anger expression in previous research. The combination of these two factors served as a measure of overall biological health risk.
The researchers also looked at measures that gauged various aspects of anger, including how often participants expressed angry feelings through verbally or physically aggressive behaviors (e.g., "I slam doors," "I say nasty things").
The data revealed that greater anger expression was associated with increased biological health risk among American participants, as previous studies have shown.
But greater anger expression was associated with reduced biological health risk among Japanese participants. And the association was not explained by other potentially related factors -- such as age, gender, chronic health conditions, smoking and alcohol consumption, social status, and experience of negative emotions more generally.
"The association between greater anger and compromised biological health, taken for granted in the current (Western) literature, was completely reversed so that greater anger was associated with better biological health among Japanese," explains Kitayama.
The researchers did not find a link between other facets of anger, such as chronic propensity toward anger or the extent to which participants suppressed feelings of anger, and health outcomes.
Together, these findings suggest that the link between anger expression and health reflects different experiences across cultural contexts. In the US, expressing anger seems to reflect the degree to which people experience negative events, while in Japan it may reflect the degree to which people feel empowered and entitled.
"Our point is that anger expression is a complex phenomenon likely motivated by a variety of factors, many of which could be culture-specific. These cultural factors must be taken into account to achieve a full understanding of the link between anger and health," the researchers write.
Kitayama and colleagues hope that future longitudinal research that follows participants over time will help to shed light on the relationship:
"Such research will help us address whether improving personal and social life styles so as to reduce anger may entail long-term health benefits."
http://www.sciencedaily.com/releases/2015/01/150107122916.htm
Chronic insomniacs may face increased risk of hypertension
January 26, 2015
Science Daily/American Heart Association
Insomniacs who take longer than 14 minutes to fall asleep face a greater risk of hypertension, according to new research. This study is the first to test whether insomnia with physiological hyperarousal, defined as a longer time to fall asleep, is linked to hypertension.
"We observed a strong correlation between the degree of physiological hyperarousal and hypertension," said Xiangdong Tang M.D., Ph.D, co- author of the study and professor of sleep medicine at West China Hospital, Sichuan University in Chengdu, China.
"In other words, those insomniacs who were hyperalert during the day and unable to relax and fall asleep during the Multiple Latency Sleep Test (MSLT) had the higher risk of hypertension," said study co-author Alexandros Vgontzas, M.D., professor of sleep research and treatment in the Department of Psychiatry at Pennsylvania State University College of Medicine in Hershey, Penn.
Insomnia is the most prevalent sleep disorder in the general population. One-fourth to one-third of the general population complains of difficulty falling asleep and about 10 percent have chronic complaints and seek medical help for insomnia.
Researchers studied 219 chronic insomniacs and 96 normal sleepers (average age 40 and more than 60 percent women). They defined chronic insomnia as difficulty sleeping for more than six months.
The participants spent one night monitored in a sleep lab and took the MLST the next day. Monitoring included four 20-minute nap opportunities at two-hour intervals: 9 a.m., 11 a.m., 1 p.m. and 3 p.m. Half the participants took 14 minutes or less to fall asleep and half took more than 14 minutes to fall asleep. Those that took more than 14 minutes to fall asleep were considered "hyperaroused."
Hypertension was based on blood pressure measures or a physician's diagnosis. Researchers controlled for confounding factors such as obesity, sleep apnea, diabetes, smoking, alcohol and caffeine use.
Chronic insomnia combined with an MSLT score greater than 14 minutes increased the odds of hypertension by 300 percent. MSLT scores greater than 17 minutes increased the odds by 400 percent.
"Long latency times to fall asleep during the day may be a reliable index of the physiological hyperarousal and biological severity of the disorder," Vgontzas said.
Traditionally, insomnia has been perceived as a nighttime sleep disorder; however, several studies suggest it's a state of 24-hour hyperarousal.
A more biologically severe type of insomnia is associated with 24-hour hyperarousal and significant cardiometabolic consequences like hypertension. The less severe form has primarily psychological roots.
Feeling hyperalert or sleepy doesn't allow people to function at their best, feel well during the day or sleep well at night, Vgontzas said.
"Although insomniacs complain of fatigue and tiredness during the day, their problem is that they cannot relax and that they are hyper," he said. "Measures that apply in sleep-deprived normal sleepers -- napping, caffeine use or other stimulants to combat fatigue -- do not apply in insomniacs. In fact, excessive caffeine worsens the hyperarousal."
http://www.sciencedaily.com/releases/2015/01/150126161759.htm
Sleep problems may impact bone health
February 3, 2015
Science Daily/Wiley
The daily rhythm of bone turnover is likely important for normal bone health, and recent research suggests that sleep apnea may be an unrecognized cause of some cases of osteoporosis. Sleep apnea's effects on sleep duration and quality, oxygen levels, inflammation, and other aspects of health may have a variety of impacts on bone metabolism, experts say.
It's important to determine the relationship between these two increasingly common diseases and to understand the biological processes that may connect them, experts note in a Journal of Bone and Mineral Research review.
"There are strong indications that daily rhythms are an intrinsic and important element of bone biology," said senior author Dr. Eric Orwoll. "If sleep disorders like obstructive sleep apnea affect bone metabolism, they may have diagnostic and therapeutic implications for many patients, including those affected by sleep apnea in their early, bone modeling years," added lead author Dr. Christine Swanson.
http://www.sciencedaily.com/releases/2015/02/150203104104.htm
How much sleep do we really need?
February 11, 2015
Science Daily/Loyola University Health System
An expert panel that examined data from 320 studies is recommending new guidelines on how much sleep people should get. The guidelines are based on age, ranging from newborns (who need 14 to 17 hours of sleep per day) to adults aged 65 and up (7 to 8 hours per day).
In the new guidelines, there's a wider range of what constitutes a good night's sleep. For example, the expert panel recommends that teens (ages 14 to 17) get 8 to 10 hours of sleep per night. The previous guideline had a narrower recommended range of 8.5 to 9.5 hours per night.
Dr. DonCarlos and other experts on the multidisciplinary panel examined findings from 320 studies reporting sleep duration findings for healthy individuals, effects of reduced or prolonged sleep duration and health consequences of too much or too little sleep. Results are published in Sleep Health: Journal of the National Sleep Foundation.
"The process was very rigorous," Dr. DonCarlos said. Dr. DonCarlos is a professor in the Department of Cell and Molecular Physiology of Loyola University Chicago Stritch School of Medicine.
The expert panel consists of 12 representatives, including Dr. DonCarlos, who were selected by medical organizations; and six sleep experts selected by the National Sleep Foundation. Dr. DonCarlos represents the American Association of Anatomists.
Dr. DonCarlos is a neuroendocrinologist who studies how hormones affect the structure of the brain. The section of the brain responsible for regulating hormone production is the hypothalamus. Hormones produced by the hypothalamus govern body temperature, hunger, stress responses, sex drive, circadian rhythms and sleep.
In addition to serving on the National Sleep Foundation expert panel, Dr. DonCarlos serves on the National Institutes of Health's Neuroendocrinology, Neuroimmunology, Rhythms and Sleep (NNRS) study section, which reviews applications for research grants.
"We still have a great deal to learn about the function of sleep," Dr. DonCarlos said. "We know it's restorative and important for memory consolidation. But we don't know the details of what the function of sleep is, even though it is how we spend one-third of our lives."
These are the sleep-time recommendations from the National Sleep Foundation expert panel:
Newborns (0-3 months): Sleep range narrowed to 14-17 hours each day (previously it was 12-18).
Infants (4-11 months): Sleep range widened two hours to 12-15 hours (previously it was 14-15).
Toddlers (1-2 years): Sleep range widened by one hour to 11-14 hours (previously it was 12-14).
Preschoolers (3-5): Sleep range widened by one hour to 10-13 hours (previously it was 11-13).
School age children (6-13): Sleep range widened by one hour to 9-11 hours (previously it was 10-11).
Teenagers (14-17): Sleep range widened by one hour to 8-10 hours (previously it was 8.5-9.5).
Younger adults (18-25): Sleep range is 7-9 hours (new age category).
Adults (26-64): Sleep range did not change and remains 7-9 hours.
Older adults (65+): Sleep range is 7-8 hours (new age category).
http://www.sciencedaily.com/releases/2015/02/150211132111.htm
Link between sleep loss, diabetes explained
February 19, 2015
Science Daily/University of Chicago Medical Center
http://images.sciencedaily.com/2015/02/150219084912-large.jpg
Lack of sleep can elevate levels of free fatty acids in the blood, accompanied by temporary pre-diabetic conditions in healthy young men. Getting enough sleep could help counteract the current epidemics of diabetes and obesity, scientists say.
The study, the first to examine the impact of sleep loss on 24-hour fatty acid levels in the blood, adds to emerging evidence that insufficient sleep -- a highly prevalent condition in modern society -- may disrupt fat metabolism and reduce the ability of insulin to regulate blood sugars. It suggests that something as simple as getting enough sleep could help counteract the current epidemics of diabetes and obesity.
"At the population level, multiple studies have reported connections between restricted sleep, weight gain, and type 2 diabetes," said Esra Tasali, MD, assistant professor of medicine at the University of Chicago and senior author of the study. "Experimental laboratory studies, like ours, help us unravel the mechanisms that may be responsible."
The researchers found that after three nights of getting only four hours of sleep, blood levels of fatty acids, which usually peak and then recede overnight, remained elevated from about 4 a.m. to 9 a.m. As long as fatty acid levels remained high, the ability of insulin to regulate blood sugars was reduced.
The results provide new insights into the connections, first described by University of Chicago researchers 15 years ago, between sleep loss, insulin resistance and heightened risk of type 2 diabetes.
The researchers recruited 19 healthy male subjects between the ages of 18 and 30. These volunteers were monitored through two scenarios in randomized order. In one, they got a full night's rest -- 8.5 hours in bed (averaging 7.8 hours asleep) during four consecutive nights. In the other, they spent just 4.5 hours in bed (averaging 4.3 hours asleep) for four consecutive nights. The two studies were spaced at least four weeks apart.
Each subject's sleep was carefully monitored, diet was strictly controlled and blood samples were collected at 15 or 30 minute intervals for 24 hours, starting on the evening of the third night of each study. The researchers measured blood levels of free fatty acids and growth hormone, glucose and insulin, and the stress hormones noradrenaline and cortisol. After four nights in each sleep condition, an intravenous glucose-tolerance test was performed.
They found that sleep restriction resulted in a 15 to 30 percent increase in late night and early morning fatty acid levels. The nocturnal elevation of fatty acids (from about 4 a.m. to 6 a.m.) correlated with an increase in insulin resistance -- a hallmark of pre-diabetes -- that persisted for a nearly five hours.
Cutting back on sleep prolonged nighttime growth hormone secretion and led to an increase in noradrenaline in the blood, both of which contributed to the increase in fatty acid levels.
Although glucose levels were unchanged, the ability of available insulin to regulate blood glucose levels decreased by about 23 percent after a short sleep, "suggesting," the authors note, "an insulin-resistant state."
"It definitely looks like a packaged deal," said the study's lead author, Josiane Broussard, PhD, a former graduate student at the University of Chicago who is now a post-doctoral research scientist at Cedars-Sinai Medical Center's Diabetes and Obesity Research Institute in Los Angeles.
"Curtailed sleep produced marked changes in the secretion of growth hormone and levels of noradrenaline -- which can increase circulating fatty acids," Broussard said. "The result was a significant loss of the benefits of insulin. This crucial hormone was less able to do its job. Insulin action in these healthy young men resembled what we typically see in early stages of diabetes."
Plasma free or non-esterified fatty acids are an important energy source for most body tissues. The demand for fatty acids goes up during exercise, for example, where they are used by cardiac and skeletal muscle; this preserves glucose for use by the brain. But constantly elevated fatty-acid levels in the blood are usually seen only in obese individuals as well as those with type 2 diabetes or cardiovascular disease. A 2012 study by a related research team emphasized the connections between sleep loss and the disruption of human fat cell function in energy regulation.
"This study opens the door to several intriguing questions," according to a Commentary in the journal by sleep specialists Jonathan Jun, MD, and Vsevolod Polotsky, MD, PhD, of Johns Hopkins University School of Medicine. Could variations in individual responses to short sleep explain susceptibility to metabolic consequences? Could dysregulation of fatty acid metabolism represent a common pathway linking various sleep disorders to metabolic syndrome? And why don't clinicians routinely ask their patients about sleep?
The study provides evidence for "potential mechanisms by which sleep restriction may be associated with insulin resistance and increased type 2 diabetes risk," the authors conclude. It supports the growing sense that insufficient sleep may disrupt fat metabolism. And it suggests that an intervention as simple as getting enough sleep could counteract the current epidemics of diabetes and obesity.
http://www.sciencedaily.com/releases/2015/02/150219084912.htm
Keep calm, anger can trigger a heart attack!
February 24, 2015
Science Daily/University of Sydney
http://images.sciencedaily.com/2015/02/150224083819-large.jpg
The risk of a heart attack is 8.5 times higher in the two hours following a burst of intense anger, researchers have found after investigating the link between acute emotional triggers and high risk of severe cardiac episodes. High levels of anxiety were associated with a 9.5 fold increased risk of triggering a heart attack in the two hours after an anxiety episode.
"Our findings confirm what has been suggested in prior studies and anecdotal evidence, even in films -- that episodes of intense anger can act as a trigger for a heart attack," said lead author Dr Thomas Buckley, Sydney Nursing School, University of Sydney, and researcher at Royal North Shore Hospital.
"The data shows that the higher risk of a heart attack isn't necessarily just while you're angry -- it lasts for two hours after the outburst.
In the study, 'anger' was qualified as 5 and above on a 1-7 scale, referring to 'very angry, body tense, clenching fists or teeth, ready to burst', up to 'enraged, out of control, throwing objects'. Anger below this level was not associated with increased risk.
"The triggers for these burst of intense anger were associated with arguments with family members (29 per cent), argument with others (42 per cent), work anger (14 per cent) and driving anger (14 per cent)," said Dr Buckley.
"The data also revealed that episodes of anxiety can also make you more likely to have heart attack.
"High levels of anxiety were associated with a 9.5 fold increased risk of triggering a heart attack in the two hours after the anxiety episode.
"Increased risk following intense anger or anxiety is most likely due to increased heart rate, blood pressure, tightening of blood vessels and increased clotting, all associated with triggering heart attacks," he said.
The study was an investigation of consecutive patients suspected of heart attack and confirmed by angiography reports at Royal North Shore hospital. Patients confirmed with acute coronary blockage were admitted, interviewed about their activities in the 48 hours before the onset of symptoms, and usual frequencies of activities were recorded for comparison.
"Although the incidence of anger-triggered heart attacks is around 2%, of the sample, those people were 8.5 times more likely to have a heart attack within two hours of the emotional episode. So while the absolute risk of any one episode triggering a heart attack is low, this data demonstrates that the danger is very present.
"Our findings highlight the need to consider strategies to protect individuals most at risk during times of acute anger.
Senior author Professor Geoffrey Tofler, Preventive Cardiology, University of Sydney said "Potential preventive approaches may be stress reduction training to reduce the frequency and intensity of episodes of anger, or avoiding activities that usually prompt such intense reactions, for instance, avoiding an angry confrontation or activity that provokes intense anxiety.
"Additionally, improving general health by minimising other risk factors, such as hypertension, high cholesterol or smoking would also lower risk.
"For those at high risk, it is possible that medication such as beta-blockers and aspirin taken at the time of a trigger may interrupt the link between the stressor and the heart attack. We are currently recruiting subjects for a study examining this option.
"Our research suggests that when managing a person with heart disease or in preventing heart disease in others, a person's frequency of anger and anxiety should also be assessed and be part of helping individuals to take care of themselves.
"Our message to people is they need to be aware that a burst of severe anger or anxiety could lead to a coronary event, so consider preventative strategies where possible," Dr Tofler said.
http://www.sciencedaily.com/releases/2015/02/150224083819.htm
Sleeping over 8 hours a day associated with greater risk of stroke
February 25, 2015
Science Daily/University of Cambridge
People who sleep for more than eight hours a day have an increased risk of stroke, according to a study -- and this risk doubles for older people who persistently sleep longer than average. However, the researchers say it is unclear why this association exists and call for further research to explore the link.
Previous studies have already suggested a possible association between sleep and risk of stroke, but today's study, published in the journal Neurology, is the first to provide detailed information about the British population and to examine the relationship between a change in sleep duration over time and subsequent stroke risk.
Researchers from the Department of Public Health and Primary Care at the University of Cambridge followed just under 10,000 people aged 42-81 years of age from the European Prospective Investigation into Cancer (EPIC)-Norfolk cohort over 9.5 years. During 1998-2000 and then again four years later, they asked the cohort how many hours on average they slept in a day and whether they generally slept well. Almost seven out of ten participants reported sleeping between six and eight hours a day, whilst one in ten reported sleeping for over eight hours a day. Participants who slept for less than six hours or more than eight hours were more likely to be older, women and less active.
Over the almost ten year period of the study, 346 participants suffered a stroke, either non-fatal or fatal stroke. After adjusting for various factors including age and sex, the researchers found that people who slept longer than eight hours a day were at a 46% greater risk of stroke than average. People who slept less than six hours a day were at an 18% increased risk, but the small number of people falling in this category meant the association was not statistically significant*.
Participants who reported persistently long sleep -- in other words, they reported sleeping over eight hours when asked at both points of the study -- were at double the risk of stroke compared to those with persistently average sleep duration (between six and eight hours a day). This risk was even greater for those whose reported sleep increased from short to long over the four years -- their risk was close to four times that of people who maintained an average sleep duration.
In addition to studying the EPIC-Norfolk cohort, the researchers carried out a study of combined data from 11 other studies related to identify the association between sleep duration and patterns of stroke risk. Their final analysis, including 560,000 participants from seven countries, supported the findings from the EPIC-Norfolk cohort study.
Yue Leng, a PhD candidate at the University of Cambridge, says: "It's apparent both from our own participants and the wealth of international data that there's a link between sleeping longer than average and a greater risk of stroke. What is far less clear, however, is the direction of this link, whether longer sleep is a symptom, an early marker or a cause of cardiovascular problems."
While older people have less work and fewer social demands and therefore often have the option of sleeping longer, previous research has shown that in fact, they tend to sleep on average for shorter periods.
The researchers say it is unclear yet why the link between sleep and stroke risk should exist. Lack of sleep has been linked with factors such as disrupted metabolism and raised levels of the 'stress hormone' cortisol, all of which may lead to higher blood pressure and increased stroke risk. However, the current study suggests that the association between longer sleep duration and higher risk of stroke was independent of normal risk factors for cardiovascular disease.
Professor Kay-Tee Khaw, senior author on the study, adds: "We need to understand the reasons behind the link between sleep and stroke risk. What is happening in the body that causes this link? With further research, we may find that excessive sleep proves to be an early indicator of increased stroke risk, particularly among older people."
http://www.sciencedaily.com/releases/2015/02/150225164004.htm
Sleep in America poll finds pain a significant challenge when it comes to Americans' sleep
March 2, 2015
Science Daily/National Sleep Foundation
A new poll in the United States finds that pain is a key factor in the gap between the amount of sleep Americans say they need and the amount they're getting -- an average 42 minute sleep debt for those with chronic pain and 14 minutes for those who've suffered from acute pain in the past week.
By contrast, there's no overall sleep debt for those without pain -- but significant numbers even in this group do have sleep problems. About one in three of those with no pain don't always or often get a good night's sleep or the sleep they need to feel their best, or have had trouble falling or staying asleep in the past week. Those problems rise even higher among individuals who do have chronic or acute pain.
The 2015 Sleep in America™ Poll finds that pain joins two related concerns -- stress and poor health -- as key correlates of shorter sleep durations and worse sleep quality. But there are paths to resolving the problem: The sleep gap narrows sharply among those who make sleep a priority.
"Taking control of your sleep by being motivated, setting a routine bedtime and creating a supportive sleep environment are relevant even for those with pain," said David Cloud, CEO of the National Sleep Foundation. "Sleep is a key marker of health, and good sleep habits are critical for improving the quality of life of those living with chronic or acute pain."
Pain is prevalent, and sleep suffers
The national, random-sample survey establishes the broad impacts of pain-related sleep loss on millions of Americans. The problem is a notable one given the number of Americans who suffer from pain. The study finds that 21 percent of Americans experience chronic pain and 36 percent have had acute pain in the past week. Those combine to a majority of the nation's adult population, 57 percent, leaving 43 percent who report being pain free.
Beyond sleep debt, self-reported sleep quality and stress levels underscore the effects of pain on sleep.
Sixty-five percent of those with no pain reported good or very good sleep quality, while only 45 percent of those with acute pain and 37 percent of those with chronic pain did the same. Additionally, 23 percent of those with chronic pain reported higher stress levels, compared with 7 percent of those without pain.
Those with acute or chronic pain are more likely to have sleep problems impact their daily lives. Among people who've had sleep difficulties in the past week, more than half of those with chronic pain say those difficulties interfered with their work. That drops to 23 percent of those without pain. People with pain are also far more apt than others to report that lack of sleep interferes with their mood, activities, relationships and enjoyment of life overall.
People with pain also feel less control over their sleep, worry more about lack of sleep affecting their health and exhibit greater sleep sensitivity. They're more likely than others to say environmental factors make it more difficult for them to get a good night's sleep. These factors include noise, light, temperature and their mattresses alike, suggesting that taking greater care of the bedroom environment may be particularly helpful to pain sufferers.
While both chronic and acute pain relate to lost sleep, the survey indicates that chronic pain is an especially powerful problem. Indeed, nearly one in four people with chronic pain, 23 percent, say they've been diagnosed with a sleep disorder by a doctor, compared with just 6 percent of all others.
"Clinicians and pain sufferers know that pain and sleep problems present together and aggravate each other. This poll confirms the relationship between pain and sleep. Fortunately, it also shows that simple steps to improving sleep can be beneficial," said Dr. Timothy Roehrs, PhD, Henry Ford Hospital.
Sleep is a key indicator of overall health
Americans who say they have very good or excellent health and quality of life report sleeping 18 to 23 minutes longer on average in the past week than those who rate their health and quality of life as just good, fair or poor. Indeed, reported sleep duration and quality decline linearly with each health rating, showing that perceptions of one's sleep and health are deeply related.
"Sleep quality and duration should be considered a vital sign, as they are strong indicators of overall health and quality of life," said Kristen Knutson, PhD, National Sleep Foundation Sleep in America™ Poll Scholar. "Extremely long or short sleep durations are associated with more specific conditions, but for many people who are close to getting the recommended seven to nine hours of sleep, getting just 15 to 30 minutes more sleep a night could make difference in how they feel."
Making sleep a priority is linked to better sleep, even among those with pain
Americans who said they were very or extremely motivated to get enough sleep reported sleeping 36 more minutes per night across the week compared with others (7.3 vs. 6.7 hours). Even among those with pain, a higher motivation to get sleep was associated with longer sleep durations and better sleep quality.
"Understanding the importance of sleep and taking a proactive approach to bed times can help everyone improve their sleep, even people with pain," said Knutson. "Taking control of your sleep is an important step in taking control of your health."
http://www.sciencedaily.com/releases/2015/03/150302182345.htm
Losing 30 minutes of sleep per day may promote weight gain and adversely affect blood sugar control
March 6, 2015
Science Daily/Endocrine Society
Losing as little as 30 minutes of sleep per day on weekdays can have long-term consequences for body weight and metabolism, a new study finds.
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"While previous studies have shown that short sleep duration is associated with obesity and diabetes, we found that as little as 30 minutes a day sleep debt can have significant effects on obesity and insulin resistance at follow up," said lead study author Professor Shahrad Taheri, MBBS, PhD, professor of medicine at Weill Cornell Medical College in Qatar, in Doha. "This reinforces earlier observations that sleep loss is additive and can have metabolic consequences."
Because of social and work commitments, people often accumulate sleep debt during weekdays and make up for lost sleep over the weekend. But weekday sleep debt may lead to long-term metabolic disruption, which may promote the onset of, or exacerbate the progression of, type 2 diabetes mellitus.
"Sleep loss is widespread in modern society, but only in the last decade have we realized its metabolic consequences," Taheri said. "Our findings suggest that avoiding sleep debt could have positive benefits for waistlines and metabolism and that incorporating sleep into lifestyle interventions for weight loss and diabetes might improve their success."
Professor Taheri and his colleagues recruited 522 patients with newly diagnosed type 2 diabetes mellitus in the Early Activity in Diabetes trial and randomized them into one of three groups: usual care, physical activity intervention, or diet and physical activity intervention.
Participants completed 7-day sleep diaries and calculated their weekday sleep debt. At baseline, the researchers recorded their height and weight to determine obesity status, measured their waist circumference for central adiposity, and analyzed their fasting blood samples for insulin sensitivity.
At baseline, compared with participants who had no weekday sleep debt, those who had weekday sleep debt were 72% more likely to be obese, and by the 6-month mark, weekday sleep debt was significantly associated with obesity and insulin resistance.
At 12 months, for every 30 minutes of weekday sleep debt at baseline, the risk of obesity and insulin resistance was significantly increased by 17% and 39%, respectively.
The authors advise that future interventions designed to slow progression or reverse metabolic disease should consider all factors -- including sleep -- that affect metabolic function. Looking toward future research, they recommend that consistent optimum sleep hygiene and education may be a key component of successful future trials in metabolic disease control.
http://www.sciencedaily.com/releases/2015/03/150306082541.htm
Moderate alcohol consumption increases attractiveness
March 9, 2015
Science Daily/University of Bristol
Consuming alcohol (equivalent to about a glass of wine) can make the drinker appear more attractive than when sober, according to new research. However, the effect disappears when more is consumed.
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Professor Marcus Munafò and colleagues in Bristol's School of Experimental Psychology asked a group of heterosexual social alcohol consumers (20 women and 20 men) to complete an attractiveness-rating task.
The volunteers were presented with images depicting an individual photographed while sober and after consuming either the equivalent of 250ml of wine or the equivalent of 500ml of wine. They were then asked to rate which of the two images was more attractive.
Photographs of individuals who had consumed the equivalent of a single glass were rated as more attractive than photographs of sober individuals. However, this was not the case for photographs of individuals who had consumed more than the equivalent of a glass.
This change in attractiveness is presumably driven by changes in appearance. The researchers suggest that vasodilation associated with alcohol consumption could lead to an increase in facial flushing, which is perceived as healthy and attractive. Low doses of alcohol may also result in an increase in positive mood that is apparent in subtle smiles and more muscle relaxation.
Understanding the mechanisms through which alcohol influences social behaviour, including factors that may impact on the likelihood of engaging in risky sexual behaviour, is important if we are to develop evidence-based public health messages, the researchers said.
http://www.sciencedaily.com/releases/2015/03/150309211523.htm
Brain waves predict our risk for insomnia
March 11, 2015
Science Daily/Concordia University
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There may not yet be a cure for insomnia, but researchers are a step closer to predicting who is most likely to suffer from it -- just in time for World Sleep Day on March 13. Researchers note that we should all keep abiding by the habits already acknowledged to promote a good night's sleep: "Avoid sources of stress when going to bed, preserve the bedroom environment for sleep and not for work, and avoid stimulation. Find ways to relax before going to sleep."
To determine the role of stress, the study examined the sleep cycles of 12 Concordia students as they went through the nerve-racking experience of finals. Measuring students' brain waves at the beginning of the school semester, Dang-Vu and his team found that students showing a lower amount of a particular pattern of brain waves were more at risk for developing insomnia afterwards in response to the stress of the exams.
The brain -- specifically the deep, inner parts of the brain called the thalamus and cortex -- produces electromagnetic activity during sleep. When monitored by diagnostic tools, this activity appears as patterns of squiggly lines that scientists refer to as spindles.
In a previous experiment, Dang-Vu and his team discovered that greater spindle activity helps sleepers resist waking, despite noise. The new study aimed to test whether there would be a similar relationship between spindles and stress.
The hypothesis proved true. "We found that those who had the lowest spindle activity tended to develop more disturbances in response to stress, when comparing sleep quality at the beginning of the semester and the end of the school semester," Dang-Vu says.
"We are not all equally armed when facing stress, in terms of how we can manage our sleep.
Some people are more vulnerable than others."
So how do you get these better spindles? Are there meditation practices you can adopt? Will gyms begin introducing spindle classes? Unfortunately, there's not a lot you can do at the moment, since spindles seem to be at least partially dependent on genetics.
But Dang-Vu, who is a medical doctor and neurologist at the Institut Universitaire de Gériatrie de Montréal, says that exploring ways to improve spindles is another prospective area for research. Measuring spindle activity may also help identify people at risk of insomnia before the condition materializes.
In the meantime, we should all keep abiding by the habits already acknowledged to promote a good night's sleep, Dang-Vu says. "Avoid sources of stress when going to bed, preserve the bedroom environment for sleep and not for work, and avoid stimulation. Find ways to relax before going to sleep."
http://www.sciencedaily.com/releases/2015/03/150311124435.htm
Prolonged shortened sleep increases blood pressure at night
March 13, 2015
Science Daily/Mayo Clinic
People exposed to prolonged periods of shortened sleep have significant increases in blood pressure during nighttime hours, researchers report in a small study of eight participants.
In this study, eight healthy, normal weight participants, ages 19 to 36, participated in a 16-day inpatient protocol, consisting of a four-day acclimation period followed by nine days of either sleep restriction (four hours of sleep per night) or normal sleep (nine hours of sleep per night), and three days of recovery. Twenty-four blood pressure monitoring at regular intervals was measured at each study phase.
During the nighttime, in the sleep restriction phase compared to the normal sleep phase, systolic (top number) and diastolic (bottom number) blood pressure averaged 115/64 millimeters of mercury (mm Hg) versus 105/57 mm Hg, respectively, researchers found. Furthermore, the expected fall in blood pressure during the night was suppressed when subjects had inadequate sleep. They also found that nighttime heart rate was higher with sleep restriction than in normal sleep.
"We know high blood pressure, particularly during the night, is one of the major risk factors for heart disease, and Americans typically do not get enough sleep," says lead author Naima Covassin, Ph.D., Mayo Clinic cardiovascular diseases research fellow. "For the first time, we demonstrated that insufficient sleep causes increases in nighttime blood pressure and dampens nocturnal blood pressure dipping by using a controlled study that mimics the sleep loss experienced by many people."
http://www.sciencedaily.com/releases/2015/03/150313130739.htm
Is too much artificial light at night making us sick?
March 18, 2015
Science Daily/University of Connecticut
Modern life, with its preponderance of inadequate exposure to natural light during the day and overexposure to artificial light at night, is not conducive to the body's natural sleep/wake cycle. A cancer epidemiologist and team members suggest such overexposure has possible ties to cancer, obesity, diabetes, and other health issues.
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It's an emerging topic in health, one that UConn Health (University of Connecticut, Farmington, Conn.) cancer epidemiologist Richard Stevens has been studying for three decades.
"It's become clear that typical lighting is affecting our physiology," Stevens says. "But lighting can be improved. We're learning that better lighting can reduce these physiological effects. By that we mean dimmer and longer wavelengths in the evening, and avoiding the bright blue of e-readers, tablets and smart phones."
Those devices emit enough blue light when used in the evening to suppress the sleep-inducing hormone melatonin and disrupt the body's circadian rhythm, the biological mechanism that enables restful sleep.
Stevens and co-author Yong Zhu from Yale University explain the known short-term and suspected long-term impacts of circadian disruption in an invited article published in the British journal Philosophical Transactions of the Royal Society B.
"It's a new analysis and synthesis of what we know up to now on the effect of lighting on our health," Stevens says. "We don't know for certain, but there's growing evidence that the long-term implications of this have ties to breast cancer, obesity, diabetes, and depression, and possibly other cancers."
As smartphones and tablets become more commonplace, Stevens recommends a general awareness of how the type of light emitted from these devices affects our biology. He says a recent study comparing people who used e-readers to those who read old-fashioned books in the evening showed a clear difference -- the e-readers showed delayed melatonin onset.
"It's about how much light you're getting in the evening," Stevens says. "It doesn't mean you have to turn all the lights off at 8 every night, it just means if you have a choice between an e-reader and a book, the book is less disruptive to your body clock. At night, the better, more circadian-friendly light is dimmer and, believe it or not, redder, like an incandescent bulb."
http://www.sciencedaily.com/releases/2015/03/150318153947.htm
Melatonin can help you get a good night's sleep in a noisy environment
March 19, 2015
Science Daily/BioMed Central
Using melatonin could provide more and better quality sleep compared to using an eye mask and earplugs in a simulated noisy and illuminated environment, according to research. This study was carried out on healthy subjects but could have future implications for intensive care unit patients.
Melatonin is the hormone secreted by the body to regulate sleep, usually in periods of darkness. Synthetically produced melatonin is used to boost the body's own melatonin levels to treat some sleep disorders, and sometimes as a means of overcoming jet lag. In ICUs, disturbances throughout the night, caused by noise and light, have been linked to slower recovery. This has led clinicians to investigate ways of reducing sleep disturbances.
Researchers from Capital Medical University in Beijing recruited 40 healthy participants to study the effects simulated ICU conditions had on sleep patterns. The research was conducted in the sleep lab of Fuzhou Children's Hospital of Fujian Province in collaboration with Professor Ling Shen. For the first four nights all participants underwent a baseline/adjustment period. During this time they slept in a sleep laboratory where on alternating nights a recording from a typical night shift at an ICU was played and light levels were the same as in the hospital.
After the first four nights the participants were randomly divided into four equal groups but continued to sleep in the simulated ICU. The first group did not receive any sleep aid. The second were provided with eye masks and earplugs. The third group took 1mg of fast-release oral melatonin when going to bed. The final group of participants was given a placebo. The participants did not know if they were receiving melatonin or placebo.
During the study period all participants' melatonin levels were tested hourly by taking blood samples. The quality of sleep was assessed using specialist equipment that measured brain activity, eye movement and muscle tension. Anxiety levels and sleep quality were also evaluated by getting participants to self-evaluate the following morning.
It was found that all sleep patterns were disturbed by exposure to the simulated ICU environment. This resulted in feelings of anxiety and reduced quality of sleep. Those participants that used either eye masks and earplugs or oral melatonin had improved sleep. Those who took melatonin were found to have decreased awakenings during the night even compared to the eye mask and earplugs group. The quality of the sleep was also found to be much improved for those taking melatonin, with reported lower anxiety levels and increased REM sleep -- thought to be linked to improved cognitive restoration.
As this study was carried out on a small number of healthy subjects over a nine-hour period it may not give a full representation of the various sleep disturbances that can occur in an ICU over 24 hours. They say future studies will need to be carried out on a larger group of diverse participants. Consideration would also need to be given for the administration of oral melatonin to critically ill patients who may also be taking other medications.
Lead researcher, Professor Xiu-Ming Xi from Fuxing Hospital, Capital Medical University, says: "Both use of oral melatonin and use of earplugs and eye masks improve sleep quality at different levels, especially melatonin. Discomfort from use of earplugs and eye masks might affect sleep quality, which wasn't reported with melatonin. Therefore, compared to earplugs and eye masks, melatonin showed up the better performance in effectiveness and the tolerance of participants."
http://www.sciencedaily.com/releases/2015/03/150319080404.htm