Low-normal sodium deemed major risk for mortality in elderly
A slightly lower serum sodium concentration within the normal range is a major risk factor for mortality in elderly adults, according to a study published in the March issue of the Journal of the American Geriatrics Society.
28 mar 2016--Shin Y. Ahn, M.D., from Seoul National University Bundang Hospital in South Korea, and colleagues randomly selected, community-based 949 elderly adults with a corrected serum sodium level between 135.0 and 145.0 mEq/L from the Korean Longitudinal Study on Health and Aging cohort. Patients were stratified by sodium level: 73 in Group 1 (sodium 135.0 to 138.0 mEq/L), 635 in Group 2 (sodium 138.1 to 142.0 mEq/L), and 241 in Group 3 (sodium 142.1 to 145.0 mEq/L).
The researchers found that deaths significantly varied by group: 34 deaths in Group 1, 124 in Group 2, and 52 in Group 3 (P < 0.001). A 2-mEq/L higher sodium level reduced the risk of death by 14.9 percent (P = 0.048). Group 1 had risk of mortality that was 2.7 times as high as that of Group 2 (P < 0.001). Those with a measured sodium level of ≤138.0 mEq/L and a corrected sodium level >138.0 mEq/L had a better survival rate than those with a measured sodium level of ≤138.0 mEq/L and a corrected sodium level of ≤138.0 mEq/L.
"Sodium level corrected according to serum glucose concentration was a more meaningful risk factor than measured sodium level," the authors write.
Aging is portrayed as mainly negative in popular music lyrics
A recent analysis of popular music reveals that while older age and aging are represented both negatively and positively in music lyrics, negative representations predominate. Most of the music texts were generated from a young person's perspective and their imaginings of old age.
25 mar 2016--While negative and positive emotions can influence health and well-being, further research is needed to explore what impact negative texts in popular music may have on older individuals.
"Recommendations from these studies suggest more sensitive, positive, inclusive and less stereotypical media reporting of issues and activities relating to ageing and older people," the authors of the Journal of Advanced Nursing study wrote. "While it may prove an impossible task and an infringement on free expression to censor all negative expressions of old age, it is important nonetheless that awareness is raised and some efforts exerted to suspend stereotypes and negative age and ageing identities in popular music due to the penetrating effects of melody and lyrics on peoples' mindsets."
More information: Jacinta Kelly et al. Representation of age and ageing identities in popular music texts, Journal of Advanced Nursing (2016). DOI: 10.1111/jan.12916
Provided by Wiley
Thursday, March 24, 2016
Adherence to Japanese diet guidelines linked to longer life
Credit: Jm Verastigue/public domainCloser adherence to Japanese dietary guidelines is associated with a lower risk of death from all causes and death from cardiovascular disease, particularly stroke, finds a study published by The BMJtoday.
24 mar 2016--The findings suggest that balanced consumption of grains, vegetables, fruits and adequate intake of fish and meat, can contribute to longevity in the Japanese population.
In 2005, the Japanese government developed the spinning top - a Japanese food guide - to illustrate the balance and quantity of food in the daily Japanese diet.
A team of researchers, led by Kayo Kurotani at the National Centre for Global Health and Medicine in Tokyo, set out to examine the association between adherence to the food guide and total and cause specific mortality.
They used data from detailed food and lifestyle questionnaires completed by 36,624 men and 42,920 women aged 45-75. Participants had no history of cancer, stroke, heart disease, or chronic liver diseaseand were followed-up for 15 years.
They found that both men and women with higher scores on the food guide (better adherence) had a 15% lower total mortality rate over 15 years. This protective association was mainly attributable to a reduction in mortality from cerebrovascular disease.
The researchers conclude: "Our findings suggest that balanced consumption of energy, grains, vegetables, fruits, meat, fish, eggs, soy products, dairy products, confectionaries, and alcoholic beverages can contribute to longevity by decreasing the risk of death, predominantly from cardiovascular disease, in the Japanese population."
More information: Quality of diet and mortality among Japanese men and women: Japan Public Health Center-based Prospective Study, The BMJ, www.bmj.com/cgi/doi/10.1136/bmj.i1209
Provided by British Medical Journal
Wednesday, March 23, 2016
Antipsychotic drugs may not be effective against delirium
A recent review of the medical literature does not support the use of antipsychotic medications for preventing or treating delirium in hospitalized patients.
23 mar 2016--Investigators analyzed 19 relevant studies. In seven studies comparing antipsychotics with placebo or no treatment for delirium prevention in postoperative patients, there was no significant effect on delirium incidence. Using data reported from all 19 studies including medical and surgical patient populations, antipsychotic use was not associated with change in delirium duration, severity, hospital length of stay, or mortality. There was considerable variability in design and outcome measures among studies, however.
"When we combine all available evidence right now, there is no compelling signal to support the routine use of antipsychotic medications to reduce delirium," said Dr. Karin Neufeld, co-author of the Journal of the American Geriatrics Societystudy.
This image represents a coronal section of hippocampal dentate gyrus (DG) from a mouse model of early Alzheimer's disease. These AD mice exhibit severe β-amyloid plaques (red) in the DG at 9-months of age. Using these mice combined with a novel viral strategy, memory engram cells (green) for a contextual fear memory were labeled. Credit: RIKENIn the early stages of Alzheimer's disease, patients are often unable to remember recent experiences. However, a new study from MIT suggests that those memories are still stored in the brain—they just can't be easily accessed.
17 mar 2016--The MIT neuroscientists report in Nature that mice in the early stages of Alzheimer's can form new memories just as well as normal mice but cannot recall them a few days later.
Furthermore, the researchers were able to artificially stimulate those memories using a technique known as optogenetics, suggesting that those memories can still be retrieved with a little help. Although optogenetics cannot currently be used in humans, the findings raise the possibility of developing future treatments that might reverse some of the memory loss seen in early-stage Alzheimer's, the researchers say.
"The important point is, this a proof of concept. That is, even if a memory seems to be gone, it is still there. It's a matter of how to retrieve it," says Susumu Tonegawa, the Picower Professor of Biology and Neuroscience and director of the RIKEN-MIT Center for Neural Circuit Genetics at the Picower Institute for Learning and Memory.
Tonegawa is the senior author of the study, which appears in the March 16 online edition of Nature. Dheeraj Roy, an MIT graduate student, is the paper's lead author.
A single memory engram cell in the hippocampal dentate gyrus region of a mouse model of early Alzheimer's disease. To optically manipulate specific connections to these engram cells, a blue light-sensitive protein oChIEF was expressed in an upstream brain region, i.e., medial entorhinal cortical inputs (red) to the DG. The majority of DG granule cells were not active during engram labeling (blue, non-engram cells). Credit: RIKENLost memories
In recent years, Tonegawa's lab has identified cells in the brain's hippocampus that store specific memories. The researchers have also shown that they can manipulate these memory traces, or engrams, to plant false memories, activate existing memories, or alter a memory's emotional associations.
Last year, Tonegawa, Roy, and colleagues found that mice with retrograde amnesia, which follows traumatic injury or stress, had impaired memory recall but could still form new memories. That led the team to wonder whether this might also be true for the memory loss seen in the early stages of Alzheimer's disease, which occurs before characteristic amyloid plaques appear in patients' brains.
To investigate that possibility, the researchers studied two different strains of mice genetically engineered to develop Alzheimer's symptoms, plus a group of healthy mice.
All of these mice, when exposed to a chamber where they received a foot shock, showed fear when placed in the same chamber an hour later. However, when placed in the chamber again several days later, only the normal mice still showed fear. The Alzheimer's mice did not appear to remember the foot shock.
"Short-term memory seems to be normal, on the order of hours. But for long-term memory, these early Alzheimer's mice seem to be impaired," Roy says.
A coronal section of hippocampal dentate gyrus from a mouse model of early Alzheimer's disease. These AD mice lack β-amyloid plaques at 7-months of age. Using these mice combined with a novel viral strategy, memory engram cells (green) for a contextual fear memory were labeled with a light-sensitive protein ChR2. Credit: RIKEN"An access problem"
The researchers then showed that while the mice cannot recall their experiences when prompted by natural cues, those memories are still there.
To demonstrate this, they first tagged the engram cells associated with the fearful experience with a light-sensitive protein called channelrhodopsin, using a technique they developed in 2012. Whenever these tagged engram cells are activated by light, normal mice recall the memory encoded by that group of cells. Likewise, when the researchers placed the Alzheimer's mice in a chamber they had never seen before and shined light on the engram cells encoding the fearful experience, the mice immediately showed fear.
"Directly activating the cells that we believe are holding the memory gets them to retrieve it," Roy says. "This suggests that it is indeed an access problem to the information, not that they're unable to learn or store this memory."
The researchers also showed that the engram cells of Alzheimer's mice had fewer dendritic spines, which are small buds that allow neurons to receive incoming signals from other neurons.
Normally, when a new memory is generated, the engram cells corresponding to that memory grow new dendritic spines, but this did not happen in the Alzheimer's mice. This suggests that the engram cells are not receiving sensory input from another part of the brain called the entorhinal cortex. The natural cue that should reactivate the memory—being in the chamber again—has no effect because the sensory information doesn't get into the engram cells.
"If we want to recall a memory, the memory-holding cells have to be reactivated by the correct cue. If the spine density does not go up during learning process, then later, if you give a natural recall cue, it may not be able to reach the nucleus of the engram cells," Tonegawa says.
Long-term connection
The researchers were also able to induce a longer-term reactivation of the "lost" memories by stimulating new connections between the entorhinal cortex and the hippocampus.
To achieve this, they used light to optogenetically stimulate entorhinal cortex cells that feed into the hippocampal engram cells encoding the fearful memory. After three hours of this treatment, the researchers waited a week and tested the mice again. This time, the mice could retrieve the memory on their own when placed in the original chamber, and they had many more dendritic spines on their engram cells.
However, this approach does not work if too large a section of the entorhinal cortex is stimulated, suggesting that any potential treatments for human patients would have to be very targeted. Optogenetics is very precise but too invasive to use in humans, and existing methods for deep brain stimulation—a form of electrical stimulation sometimes used to treat Parkinson's and other diseases—affect too much of the brain.
"It's possible that in the future some technology will be developed to activate or inactivate cells deep inside the brain, like the hippocampus or entorhinal cortex, with more precision," Tonegawa says. "Basic research as conducted in this study provides information on cell populations to be targeted, which is critical for future treatments and technologies."
More information: Dheeraj S. Roy et al. Memory retrieval by activating engram cells in mouse models of early Alzheimer's disease, Nature (2016). DOI: 10.1038/nature17172
Provided by Massachusetts Institute of Technology
Wednesday, March 16, 2016
The up- and downside of caloric restriction for aging and health
It's already well known that a diet may have a life-extending effect. Researchers from Leibniz Institute on Aging – Fritz Lipmann Institute (FLI) in Jena, Germany, now showed that besides improving the functionality of stem cells in mice, a caloric restriction also leads to a fatale weakening of their immune system – counteracting the life-lengthening effect of a diet. The results are published in the Journal of Experimental Medicine on March, 14. 2016.
16 mar 2016--Only few years ago, researchers succeeded in prolonging the lifespan of worm C. elegans, fruit fly D. melongaster and rats by almost 50% through a simple caloric restriction – which immediately fueled hopes for having found one key to a longer life also for humans. However, transferring these results to long-lived primates short after was not equally successful and cooled down enthusiasms quite quickly. Now, aging researcher Karl Lenhard Rudolph, Scientific Director at the Leibniz Institute on Aging – Fritz Lipmann Institute (FLI) in Jena, Germany, and his team showed that caloric restriction even has a severe downside. In feeding experiments, the stem cells of mice, which were set on a diet, were found to age slower – but the murine immune system was almost completely cut down. Outside of optimal, sterile laboratory conditions, this could lead to severe live-shortening infections. The results of the study are published in the Journal of Experimental Medicine's current issue.
Caloric restriction slows down the aging of blood stem cells
The study focused on the effects of caloric restriction on blood stem cells (so-called hematopoietic stem cells, HSC) that are responsible for building red blood cells or lymphocytes (immune cells). Like for any other adult stem cell, HSC functionality decreases with every single cell division – the stem cells age. This is why they stay in a resting phase (quiescence) most of the time and are only activated when a massive cell reproduction is required (e.g. after acute blood loss). In their study, the researchers from Jena investigated how a 30% food restriction effects stem cell aging in mice. One main result was that the HSC stayed in a quiescent state even if simulated stress would have required their activation. This effect was found regardless of how long the diet lasted. Thus, during diet, the blood stem cells did not age at all and their functionality to build new blood cells remained increased even one year after diet.
Caloric restriction weakens the immune system
But the long-term diet had a downside, as well: The mice's immune system almost completely was cut down. Although the diet had no strong effect on the overall cell number of blood cells, the production of lymphocytes – needed for immune defense – was decreased by up to 75%. As a consequence, mice were particularly prone to bacterial infections.
Slowing down aging under laboratory conditions is not yet transferable to humans
"The study provides the first experimental evidence that long-term caloric restriction – as intervention to slow down aging – increases stem cell functionality, but results in immune defects in the context of prolonged bacterial infection, too. Thus, positive effects of a diet are not transferable to humans one to one", Rudolph sums up the study results. Even if – under laboratory conditions – aging of single cells or tissues may be slowed down through a diet, the immune suppression may have fatal consequences in real life. To benefit from caloric restriction or medicinal mimetika aiming at increasing health in the elderly, possible risks of such interventions to come down with life-threatening infections remain to be elucidated. "In sepsis patients, we see a higher survival rate for those with a higher body weight than for patients who are very lean", Prof. Dr. Michael Bauer, Director of the Center for Sepsis Control and Care at University Hospital Jena (UKJ), concurs.
More information: Duozhuang Tang et al. Dietary restriction improves repopulation but impairs lymphoid differentiation capacity of hematopoietic stem cells in early aging, The Journal of Experimental Medicine (2016). DOI: 10.1084/jem.20151100
Provided by Leibniz Institute on Aging
Sunday, March 13, 2016
Latin dancing may have health benefits for older adults
A four-month dance program helped older Latino adults walk faster and improved their physical fitness, which may reduce their risk for heart disease, according to research presented at the American Heart Association's Epidemiology/Lifestyle 2016 Scientific Sessions.
13 mar 2016--Researchers at the University of Illinois at Chicago tested whether a community-based intervention focused on Latin dancing could benefit 54 Spanish-speaking adults (about 65 years old, 80 percent Mexican female) who were not very physically active. Participants were randomly assigned to either participate in a dance program twice a week for four months or to attend a health education program. All participants completed questionnaires about their leisure time physical activity and a 400-meter walk test at the start and end of the study.
After four months of twice-weekly Latin dancing, researchers found:
Dancers walked faster and were more physically active during their leisure time than before they started dancing.
Dancers completed a 400-meter walk in just under 392 seconds compared with almost 430 seconds at the start of the study.
Leisure physical activity rose from 650 minutes to nearly a total of 818 minutes per week.
Four signs that a geriatric ER patient should be admitted to the hospital
Four reasons to admit a senior from the ER to the hospital (Annals of Emergency Medicine). Credit: American College of Emergency PhysiciansOlder adults who go to the emergency department with cognitive impairment, a change in disposition plan from admit to discharge, low blood pressure and elevated heart rate were more likely to be admitted to the intensive care unit (ICU) or to die within 7 days. The results of a matched case-control study of patients age 65 or older who died or were admitted to the ICU within 7 days of being evaluated in the emergency department were published online Wednesday in Annals of Emergency Medicine ("Poor Outcomes Following Emergency Department Discharge of the Elderly: A Case-Control Study").
11 mar 2016--"Emergency physicians must exercise extra caution when making the decision to admit or discharge a geriatric patient," said Gelareh Gabayan, MD, MSHS of the Department of Medicine at the University of California at Los Angeles. "These patients tend to be more delicate than their younger counterparts. Even abnormal vital signs, like blood pressure and heart rate, are associated with potentially catastrophic events for patients who are discharged from the ER rather than admitted."
Patients age 65 or older with a change in disposition plan (from admit to discharge), acute or chronic cognitive impairment or mental status changes, and abnormal vital signs (a systolic blood pressure below 120 and heart rate above 90) had a greater likelihood of experiencing death or an ICU admission within 7 days of being discharged from the emergency department. (The change in disposition could be directed by a physician or by the patient leaving the hospital against medical advice.)
"Both patient families and hospital administrators can pressure emergency physicians to discharge seniors from the emergency department, but our study supports caution in these decisions," said Dr. Gabayan. "Our study identifies the patients at risk and the findings show that even seemingly small indicators can add up to something dangerous in these vulnerable patients. It is important to note, however, that this study does not encourage that all older adults be admitted. The findings should act as a tool for emergency department providers."
More information: Gelareh Z. Gabayan et al. Poor Outcomes After Emergency Department Discharge of the Elderly: A Case-Control Study, Annals of Emergency Medicine (2016). DOI: 10.1016/j.annemergmed.2016.01.007
Provided by American College of Emergency Physicians
Wednesday, March 09, 2016
Landmark editorial identifies microbes as major cause of Alzheimer's disease
A worldwide team of senior scientists and clinicians have come together to produce an editorial which indicates that certain microbes - a specific virus and two specific types of bacteria—are major causes of Alzheimer's disease. Their paper, which has been published online in the highly regarded peer-reviewed journal, Journal of Alzheimer's disease, stresses the urgent need for further research—and more importantly, for clinical trials of anti-microbial and related agents to treat the disease.
09 mar 2016--This major call for action is based on substantial published evidence and research into Alzheimer's. The team's landmark editorial summarises the abundant data implicating these microbes, but until now this work has been largely ignored or dismissed as controversial—despite the absence of evidence to the contrary. Therefore, proposals for the funding of clinical trials have been refused, despite the fact that over 400 unsuccessful clinical trials for Alzheimer's based on other concepts were carried out over a recent 10-year period.
Opposition to the microbial concepts resembles the fierce resistance to studies some years ago which showed that viruses cause certain types of cancer, and that a bacterium causes stomach ulcers. Those concepts were ultimately proved valid, leading to successful clinical trials and the subsequent development of appropriate treatments.
Professor Douglas Kell of The University of Manchester's School of Chemistry and Manchester Institute of Biotechnology is one of the editorial's authors. He says that supposedly sterile red blood cells were seen to contain dormant microbes, which also has implications for blood transfusions. "We are saying there is incontrovertible evidence that Alzheimer's disease has a dormant microbial component, and that this can be woken up by iron dysregulation. Removing this iron will slow down or prevent cognitive degeneration – we can't keep ignoring all of the evidence."
Professor Resia Pretorius of the University of Pretoria, who worked with Douglas Kell on the editorial, said "The microbial presence in blood may also play a fundamental role as causative agent of systemic inflammation, which is a characteristic of Alzheimer's disease—particularly, the bacterial cell wall component and endotoxin, lipopolysaccharide. Furthermore, there is ample evidence that this can cause neuroinflammation and amyloid-β plaque formation."
The findings of this editorial could also have implications for the future treatment of Parkinson's disease, and other progressive neurological conditions.
Provided by University of Manchester
Saturday, March 05, 2016
Understanding ageism prolongs your life
Perceptions about ageism makes people think of older people and is a form of discrimination. This according to Fredrik Snellman at Umeå University who believes that the concept needs to be redefined to mirror all people's practical experiences of ageing. The results have been published in the journal Nordic Psychology.
05 mar 2016--"We are using age in many ways to organise our own and other people's lives and to make our social world understandable. The usage can sometimes be prejudiced and have undesirable consequences to us all. It is often hidden and the ways it is noticeable in everyday life can seem trivial. That is why it is of importance to make visible the everyday use of ageism and find new terms for them," says Fredrik Snellman.
In the article, Snellman criticises previous scientific findings and a suggested definition of the term of attitude and the phenomenon 'ageism'. According to Snellman, the concept of ageism needs to be redefined to mirror all people's practical experiences of the chronological, social, biological and psychological parts of ageing. Ageism should be portrayed as significant for people of all ages rather than only the older population.
Furthermore, Snellman's study draws parallels to another study that has shown that negative ageism – or negative attitudes about older people and ageing – stands in connection with an increased mortality among the population. The study shows that individuals with a higher level of negative attitudes (confirmed at the age of 50 or earlier) live on average 7.5 years shorter in comparison to those who have a more positive attitude towards ageing. That is proof of why an increased awareness is needed and should in all likelihood arouse people's interest in their own attitudes.
Snellman is critical towards ageism being portrayed as difficulty only for older people despite researchers in the previous study to have express ambition to eliminate the same. Regardless of the strive within science to avoid differentiating between 'us and them – old and young' which often forms the basis of the hidden and rarely questioned way of creating inequality – science upholds the difference.
"Awareness and a lively debate about the complex problem of ageism is needed, in particular about how age enables and limits our lives throughout the course of life. A better understanding of how 'older people' besides distinguishing a group of the population also is an intergenerational phenomenon is necessary. Age-related indifference does not suddenly appear when we grow old. It appears gradually and in different ways at all ages," says Snellman.
More information: Fredrik Snellman. Whose ageism? The reinvigoration and definitions of an elusive concept, Nordic Psychology (2016). DOI: 10.1080/19012276.2015.1125301
