In the Hospital, the Noisy Hospital, the Patient Sleeps Tonight?

June 11, 2012 —
Science Daily/Brigham and Women's Hospital
In the hospital it is not only direct patient care, but also the environment that contributes to recovery. A critical component of a healing environment is a peaceful space for a patient to get enough sleep.

However, according to a new study by researchers at Brigham and Women's Hospital (BWH), Massachusetts General Hospital and Cambridge Health Alliance, there are certain noises in a common hospital setting that can disrupt sleep. Such disruption can negatively affect brain activity and cardiovascular function.

The study will be published online in Annals of Internal Medicine on June 12, 2012.

"Hospitals and actually most urban sleep environments are increasingly noise-polluted," said Orfeu Buxton, PhD, BWH Division of Sleep Medicine, co-lead study author. "This study highlights the importance of sleep for restoration and healing that is particularly important for hospitalized patients."

The researchers recruited 12 healthy volunteers to participate in the three-day study which took place in a sleep laboratory. On the first night, the participants slept without any disruption. On the following two nights, they were presented with 14 recorded sounds commonly heard in a hospital setting.

Among the 14 sounds were an intravenous alarm, telephone, ice machine, voices in the hall, outside traffic and a helicopter. The sounds were presented at increasing decibel levels during specific sleep stages.

As expected, the louder the sound the more likely to disrupt sleep. However, there were unexpectedly large differences in sleep disruption based on sound type -- independent of how loud the sound. The researchers found that of all sound types, electronic sounds were most arousing, even at a volume just above a whisper.

Also, a person's sleep stage affected whether sound would lead to arousal. During non-rapid eye movement (NREM) sleep, sound type influenced arousal; whereas, during rapid eye movement (REM) sleep, volume was more influential.

Sleep disruption due to hospital noises also affected cardiovascular function.

"Beyond disturbing sleep itself, we showed that noise-induced sleep disruptions -- even subtle ones, beneath conscious awareness -- lead to temporary elevations in heart rate," said Jeffrey Ellenbogen, MD, director of Sleep Medicine at MGH, co-lead study author. "While these effects were modest in size, our concern is that repeated disruptions, as might occur in a hospital room, may jeopardize the health of our most vulnerable populations."

The study systematically quantifies the disruptive capacity of hospital sounds on sleep, providing evidence that it is important to improve the acoustic environments of new and existing health care facilities to enable the highest quality of care.

"There are several strategies for protecting patient sleep in hospitals," said Jo Solet, PhD, Cambridge Health Alliance, senior study author. "These include acoustic performance guidelines for design and construction, altered night-care routines, and enhanced technologies for clinician communication and medical alarms."
http://www.sciencedaily.com/releases/2012/06/120611193526.htm

Preventing or Better Managing Diabetes May Prevent Cognitive Decline

June 21, 2012 —
Science Daily/University of California - San Francisco
Preventing diabetes or delaying its onset has been thought to stave off cognitive decline -- a connection strongly supported by the results of a 9-year study led by researchers at the University of California, San Francisco (UCSF) and the San Francisco VA Medical Center.

Earlier studies have looked at cognitive decline in people who already had diabetes. The new study is the first to demonstrate that the greater risk of cognitive decline is also present among people who develop diabetes later in life. It is also the first study to link the risk of cognitive decline to the severity of diabetes.

The result is the latest finding to emerge from the Health, Aging, and Body Composition (Health ABC) Study, which enrolled 3,069 adults over 70 at two community clinics in Memphis, TN and Pittsburgh, PA beginning in 1997. All the patients provided periodic blood samples and took regular cognitive tests over time.

When the study began, hundreds of those patients already had diabetes. A decade later, many more of them had developed diabetes, and many also suffered cognitive decline. As described this week in Archives of Neurology, those two health outcomes were closely linked.

People who had diabetes at the beginning of the study showed a faster cognitive decline than people who developed it during the course of the study -- and these people, in turn, tended to be worse off than people who never developed diabetes at all. The study also showed that patients with more severe diabetes who did not control their blood sugar levels as well suffered faster cognitive declines.

"Both the duration and the severity of diabetes are very important factors," said Kristine Yaffe, MD, the lead author of the study. "It's another piece of the puzzle in terms of linking diabetes to accelerated cognitive aging."

An important question for future studies, she added, would be to ask if interventions that would effectively prevent, delay or better control diabetes would also lower people's risk of cognitive impairment later in life.

Yaffe is the Roy and Marie Scola Endowed Chair of Psychiatry; professor in the UCSF departments of Psychiatry, Neurology and Epidemiology and Biostatistics; and Chief of Geriatric Psychiatry and Director of the Memory Disorders Clinic at the San Francisco VA Medical Center.

Diabetes and Cognitive Decline

Diabetes is a chronic and complex disease marked by high levels of sugar in the blood that arise due to problems with the hormone insulin, which regulates blood sugar levels. It is caused by an inability to produce insulin (type 1) or an inability to respond correctly to insulin (type 2).

A major health concern in the United States, diabetes of all types affects an estimated 8.3 percent of the U.S. population -- some 25.8 million Americans -- and costs U.S. taxpayers more than $200 billion annually. In California alone, an estimated 4 million people (one out of every seven adults) has type 2 diabetes and millions more are at risk of developing it. These numbers are poised to explode in the next half century if more is not done to prevent the disease.

Over the last several decades, scientists have come to appreciate that diabetes affects many tissues and organs of the body, including the brain and central nervous system -- particularly because diabetes places people at risk of cognitive decline later in life.

In their study the scientists looked at a blood marker known as "glycosylated hemoglobin," a standard measure of the severity of diabetes and the ability to control it over time. The marker shows evidence of high blood sugar because these sugar molecules become permanently attached to hemoglobin proteins in the blood. Yaffe and her colleagues found that greater levels of this biomarker were associated with more severe cognitive dysfunction.

While the underlying mechanism that accounts for the link between diabetes and risk of cognitive decline is not completely understood, Yaffe said, it may be related to a human protein known as insulin degrading enzyme, which plays an important role in regulating insulin, the key hormone linked to diabetes. This same enzyme also degrades a protein in the brain known as beta-amyloid, a brain protein linked to Alzheimer's disease.
http://www.sciencedaily.com/releases/2012/06/120621195915.htm

Sleep Deprivation Effect On the Immune System Mirrors Physical Stress

June 30, 2012 —
Science Daily/American Academy of Sleep Medicine
Severe sleep loss jolts the immune system into action, reflecting the same type of immediate response shown during exposure to stress, a new study reports.

Researchers in the Netherlands and United Kingdom compared the white blood cell counts of 15 healthy young men under normal and severely sleep-deprived conditions. The greatest changes were seen in the white blood cells known as granulocytes, which showed a loss of day-night rhythmicity, along with increased numbers, particularly at night.

"Future research will reveal the molecular mechanisms behind this immediate stress response and elucidate its role in the development of diseases associated with chronic sleep loss," said Katrin Ackermann, PhD, the study's lead author. "If confirmed with more data, this will have implications for clinical practice and for professions associated with long-term sleep loss, such as rotating shift work."

Previous studies have associated sleep restriction and sleep deprivation with the development of diseases like obesity, diabetes and hypertension. Others have shown that sleep helps sustain the functioning of the immune system, and that chronic sleep loss is a risk factor for immune system impairment.

For this study, white blood cells were categorized and measured from 15 young men following a strict schedule of eight hours of sleep every day for a week. The participants were exposed to at least 15 minutes of outdoor light within the first 90 minutes of waking and prohibited from using caffeine, alcohol or medication during the final three days. All of this was designed to stabilize their circadian clocks and minimize sleep deprivation before the intensive laboratory study.

White blood cell counts in a normal sleep/wake cycle were compared to the numbers produced during the second part of the experiment, in which blood samples were collected during 29 hours of continual wakefulness.

"The granulocytes reacted immediately to the physical stress of sleep loss and directly mirrored the body's stress response," said Ackermann, a postdoctoral researcher at the Eramus MC University Medical Center Rotterdam in the Netherlands.
http://www.sciencedaily.com/releases/2012/07/120701191638.htm

How Stress and Depression Can Shrink the Brain

Aug. 12, 2012 —

Science Daily/Yale University

Major depression or chronic stress can cause the loss of brain volume, a condition that contributes to both emotional and cognitive impairment. Now a team of researchers led by Yale scientists has discovered one reason why this occurs -- a single genetic switch that triggers loss of brain connections in humans and depression in animal models.

"We wanted to test the idea that stress causes a loss of brain synapses in humans," said senior author Ronald Duman, the Elizabeth Mears and House Jameson Professor of Psychiatry and professor of neurobiology and of pharmacology. "We show that circuits normally involved in emotion, as well as cognition, are disrupted when this single transcription factor is activated."

http://www.sciencedaily.com/releases/2012/08/120812151659.htm

Zebrafish Study Explains Why the Circadian Rhythm Affects Your Health

Aug. 28, 2012 —
Science Daily/Linköping Universitet

https://www.sciencedaily.com/images/2012/08/120828073049_1_540x360.jpg
A normal circadian rhythm regulates the genes needed to form the signalling substance VEGF, which in turn is necessary for blood vessel growth (angiogenesis). Light at night disturbs the circadian rhythm, and VEGF cannot be produced – blood vessel growth is inhibited, which can be seen in the microscope images at right.
Credit: Lasse Dahl Jensen

Disruptions to the circadian rhythm can affect the growth of blood vessels in the body, thus causing illnesses such as diabetes, obesity, and cancer, according to a new study from Linköping University and Karolinska Institutet in Sweden.

In an article now being published in the scientific journal Cell Reports, it is demonstrated for the first time that disruption of the circadian rhythm immediately inhibit blood vessel growth in zebra fish embryos.
http://www.sciencedaily.com/releases/2012/08/120828073049.htm

Lights Out? The Dangers of Exposure to Light at Night

Sep. 10, 2012 —
University of Haifa
A panel of world experts discussed "Light Pollution and its Ecophysiological Consequences" and shed light on the extent of the dangers and harm that night-time artificial lighting causes, emphasizing that it is the short wavelength illumination that we have come to know as "eco-friendly illumination" that is causing the most harm (primarily LED lighting).

"The most important thing for us is to raise awareness of the dangers of artificial light at night and we have already come a long way now that the American Medical Association (AMA) recently announced its new policy recognizing adverse health effects of exposure to light at night and encouraging further research into the matter," said Prof. Abraham Haim, a leading authority on light pollution, who coordinated the 21st International Congress of Zoology (ICZ) that was held last week at the University of Haifa, Israel.

The participants were in full agreement that exposure to light at night affects circadian rhythms in nature -- humans, animals and plants -- which when thrown off can result in various illnesses and adverse symptoms.
http://www.sciencedaily.com/releases/2012/09/120910111702.htm

Fruit Flies Reveal New Evolutionary Link for Studying Human Health How They Control Body Temperature Through Circadian Rhythm

Sep. 13, 2012 —
Science Daily/Cincinnati Children's Hospital Medical Center

https://www.sciencedaily.com/images/2012/09/120913123223_1_540x360.jpg
Male common fruit fly (Drosophila melanogaster). Drosophila fruit flies are a common tool in life sciences research for modeling human development and disease. Scientists continue learn more about how molecular processes in fruit flies may have similarities to human development that are conserved through the long process of evolution.
Credit: iStockphoto

New research reveals that fruit flies and mammals may share a surprising evolutionary link in how they control body temperature through circadian rhythm, unlocking new ways to study the insects as models of human development and disease.

The study posted online Sept. 13 by Current Biology reports that similar to people, Drosophila fruit flies -- a common research tool in life sciences -- have a genetically driven internal clock. This circadian clock prompts the insects to seek out warmer or cooler external temperatures according to the time of the day. Cold-blooded creatures change behavior to alter body temperature, usually by seeking out different external temperatures. But fruit flies are the first cold-blooded species to demonstrate their modification of temperature preference behavior is controlled by a circadian clock.

"We show that Drosophila fruit flies exhibit a daily temperature preference rhythm that is low in the morning, high in the evening and that follows a similar pattern as body temperature rhythms in humans," said Fumika N. Hamada, PhD, principal investigator and a researcher in the Division of Pediatric Ophthalmology at Cincinnati Children's Hospital Medical Center. "This study also reports the first systematic analysis of the molecular and neural mechanisms underlying temperature preference rhythm in fruit flies."

The research is important to understanding how regulation of daily body temperature is linked to homeostasis -- the body's ability to maintain a stable internal environment while exposed to changes in the external environment. Failure to manage related stress and maintain homeostasis can lead to abnormal function and disease, Hamada said.

The circadian clock's internal control of body temperature rhythm in warm-blooded mammals, including humans, allows them to maintain homeostasis by regulating sleep and metabolic energy use. The study by Hamada and colleagues is the first to demonstrate that fruit flies have a similar circadian clock system for temperature control, although one more influenced by external temperatures than for mammals. It also is the first to show that Drosophila's behavior modification to adjust body temperature is not controlled by a subset of pacemaker neurons in the brain responsible for locomotor activity.

By subjecting a variety of genetically altered flies to different degrees of light and darkness and then analyzing the insect's brains, the scientists identified a pacemaker neuron in the dorsal region of the fruit fly brain called DN2 that controls the bug's temperature preference rhythm. The function of this neural circuit had previously been unknown, the researchers said.

Hamada said continued study of the newly discovered circadian clock for Drosophila temperature preference rhythm may help explain mechanisms that underlie body temperature control in animals. It also could provide a better understanding of circadian rhythm's changeability from external influences.

Funding support for the study came from the National Institutes of Health (RO1grants GM079182 and NS052854), the March of Dimes, funding from the Precursor Research for Embryonic Science and Technology (PRESTO) program at the Japan Science Technology Agency, and a Trustee Grant from Cincinnati Children's Hospital Medical Center. The first author of the study was Haruna Kaneko, PhD., a member of Hamada's laboratory team. Also collaborating were Paul Hardin, Department of Biology and Center for Biological Clocks Research at Texas A&M University, and Patrick Emery, Department of Neurobiology and Program in Neuroscience, at the University of Massachusetts Medical School.
http://www.sciencedaily.com/releases/2012/09/120913123223.htm

Making Headway On Beta-Blockers and Sleep

Sep. 28, 2012 —
Science Daily/Brigham and Women's Hospital
Over 20 million people in the United States take beta-blockers, a medication commonly prescribed for cardiovascular issues, anxiety, hypertension and more. Many of these same people also have trouble sleeping, a side effect possibly related to the fact that these medications suppress night-time melatonin production. Researchers at Brigham and Women's Hospital (BWH) have found that melatonin supplementation significantly improved sleep in hypertensive patients taking beta-blockers.

"Over the course of three weeks, none of the study participants taking the melatonin showed any of the adverse effects that are often observed with other, classic sleep aids. There were also no signs of 'rebound insomnia' after the participants stopped taking the drug," explained Scheer, who is also an assistant professor of Medicine at Harvard Medical School. "In fact, melatonin had a positive carry-over effect on sleep even after the participants had stopped taking the drug."
http://www.sciencedaily.com/releases/2012/09/120928085629.htm

'I'm Bored!' -- Research On Attention Sheds Light On the Unengaged Mind

Sep. 26, 2012 —
Science Daily/Association for Psychological Science
You're waiting in the reception area of your doctor's office. The magazines are uninteresting. The pictures on the wall are dull. The second hand on the wall clock moves so excruciatingly slowly that you're sure it must be broken. You feel depleted and irritated about being stuck in this seemingly endless moment. You want to be engaged by something -- anything -- when a thought, so familiar from childhood, comes to mind: "I'm bored!"

Although boredom is often seen as a trivial and temporary discomfort that can be alleviated by a simple change in circumstances, it can also be a chronic and pervasive stressor that can have significant consequences for health and well-being.

Boredom at work may cause serious accidents when safety depends on continuous vigilance, as in medical monitoring or long-haul truck driving. On a behavioral level, boredom has been linked with problems with impulse control, leading to overeating and binge eating, drug and alcohol abuse, and problem gambling. Boredom has even been associated with mortality, lending grim weight to the popular phrase "bored to death."

Although it's clear that boredom can be a serious problem, the scientific study of boredom remains an obscure niche of research, and boredom itself is still poorly understood. Even though it's a common experience, boredom hasn't been clearly defined within the scientific community.

Psychological scientist John Eastwood of York University (Ontario, Canada) and colleagues at the University of Guelph and the University of Waterloo wanted to understand the mental processes that underlie our feelings of boredom in order to create a precise definition of boredom that can be applied across a variety of theoretical frameworks. Their new article, which brings together existing research on attention and boredom, is published in the September 2012 issue of Perspectives on Psychological Science, a journal of the Association for Psychological Science.

Drawing from research across many areas of psychological science and neuroscience, Eastwood and colleagues define boredom as "an aversive state of wanting, but being unable, to engage in satisfying activity," which arises from failures in one of the brain's attention networks.

Specifically, we're bored when:
•    We have difficulty paying attention to the internal information (e.g., thoughts or feelings) or external information (e.g., environmental stimuli) required for participating in satisfying activity
•    We're aware of the fact that we're having difficulty paying attention
•    We believe that the environment is responsible for our aversive state (e.g., "this task is boring," "there is nothing to do").

The researchers are confident that integrating the disparate fields of cognitive neuroscience, social psychology, and clinical psychology will produce a more thorough understanding of boredom and attention -- phenomena which are ubiquitous and intimately linked.

Armed with a precise and broadly applicable definition of boredom that gets at the underlying mental processes, the authors identify important next steps in research on boredom. Eastwood and his colleagues hope to help in the discovery and development of new strategies that ease the problems of boredom sufferers and address the potential dangers of cognitive errors that are often associated with boredom.
http://www.sciencedaily.com/releases/2012/09/120926153032.htm

Poorer Lung Health Leads to Age-Related Changes in Brain Function

Oct. 8, 2012 —
Science Daily/Ohio State University
Keeping the lungs healthy could be an important way to retain thinking functions that relate to problem-solving and processing speed in one's later years, new research suggests.

While these two types of "fluid" cognitive functions were influenced by reduced pulmonary function, a drop in lung health did not appear to impair memory or lead to any significant loss of stored knowledge, the study showed.

Researchers used data from a Swedish study of aging that tracked participants' health measures for almost two decades. An analysis of the data with statistical models designed to show the patterns of change over time determined that reduced pulmonary function can lead to cognitive losses, but problems with cognition do not affect lung health.

"The logical conclusion from this is that anything you could do to maintain lung function should be of benefit to fluid cognitive performance as well," said Charles Emery, professor of psychology at Ohio State University and lead author of the study. "Maintaining an exercise routine and stopping smoking would be two primary methods. Nutritional factors and minimizing environmental exposure to pollutants also come into play."

Emery said the analysis also offers insights into the process of human aging. While one theory of aging holds that all functions that slow down do so at the same rate, this study suggests that some aspects of functional decline contribute to a change in the rate of other areas of decline.

"In this case, pulmonary functioning may be contributing to other aspects of functioning," he said. "It starts to speak to the bigger question: What are the processes involved in aging?"

The study is published in the current issue of the journal Psychological Science.

The study sample consisted of 832 participants between ages 50 and 85 who were assessed in up to seven waves of testing across 19 years as part of the Swedish Adoption/Twin Study of Aging. Emery and colleagues used data from pulmonary and cognitive tests conducted in the Swedish study.

Lung function was measured in two ways: forced expiratory volume, or how much air a person can push out of the lungs in one second, and forced vital capacity, the volume of air that is blown out after a deep inhalation.

The Swedish participants also were tested in four cognitive domains that measured verbal abilities associated with stored knowledge, memory, spatial abilities related to problem-solving and processing speed -- which included the ability to write correct responses quickly.

The researchers entered the data into structural equation models that allow for interaction between the components being compared -- in this case, lung function and cognitive function -- as well as the trajectory of the changes over time. These dual-change-score models can be likened to a horse race, Emery said.

"We were looking for effects in both directions. We had previously looked in simpler models and found that pulmonary function did predict cognitive function, but there are some studies that show the opposite direction. It was important for us to go into this with an open mind and use this modeling to test both directions," he said.

This kind of statistical analysis did not quantify the effects, but showed clear trends between a decline in lung function and steeper losses in the two types of "fluid" cognitive function. A small effect was seen on verbal tasks, as well. Pulmonary function change had no influence on memory performance.

The study also showed that changes in cognitive function did not predict lung outcomes.

"In these models the relationship is consistently moving from pulmonary function to cognitive function and not the other way," said Emery, also a professor of internal medicine and an investigator in Ohio State's Institute for Behavioral Medicine Research.

The declines seen in this study are expected with age, he noted. And the elements of cognitive function that were not influenced by lung function -- memory and retrieval of stored knowledge -- are not typically associated with normal aging.

"We know, for example, that the speed at which people can perform the processing task does decline with age. But now we have data that suggests pulmonary function actually predicts that decline," he said.

Though this study does not explain what a loss of pulmonary function does to the brain, the researchers speculated that reduced lung health could lower the availability of oxygen in the blood that could in turn affect chemicals that transmit signals between brain cells.
http://www.sciencedaily.com/releases/2012/10/121008144258.htm