Friday, August 31, 2012

New diagnostic biomarkers offer ray of hope for Alzheimer's disease

Alzheimer's disease (AD) is one of the most common brain disorders, with an estimated 35 million people affected worldwide. In the last decade, research has advanced our understanding of how AD affects the brain. However, diagnosis continues to rely primarily on neuropsychological tests which can only detect the disease after clinical symptoms begin. In a supplement to the Journal of Alzheimer's Disease, investigators report on the development of imaging-based biomarkers that will have an impact on diagnosis before the disease process is set in motion.
31 aug 2012--"There is an urgent need for the development of reliable diagnostic biomarkers that can detect AD pathology at an incipient phase," says Guest Editor Dr. Pravat Mandal, Adjunct Associate Professor of the Department of Radiology, Johns Hopkins Medicine, Baltimore, MD and Additional Professor, National Brain Research Center, India. "This special issue focuses on the latest strides made in identifying diagnostic biomarkers using state-of-the-art imaging modalities."
The issue looks at the application of various magnetic resonance imaging (MRI) technologies for diagnosing AD and monitoring the progression of the disease. For example, Brian T. Gold and colleagues report on the use of diffusion tension imaging (DTI) to identify changes in the white matter of patients with amnestic mild cognitive impairment (MCI), an early symptom of AD. Charles D. Smith and colleagues describe MRI-based detection of key structural alterations in cognitively normal subjects that can serve as a predictor of memory impairment.
While MRI provides information about the anatomy of the brain, functional MRI (fMRI) provides crucial information about the regions involved during specific tasks. The issue explores how fMRI can detect changes in functional activation and connectivity in AD patients. Monitoring alterations in functional brain activity related to visual processing deficits in AD has immense potential as an early diagnostic biomarker, according to a review by Dr. Mandal and colleagues. By using fMRI to study normal older individuals, patients with MCI, and those with AD as they perform cognitive tasks and at rest, Jasmeer P. Chhatwal and Reisa Sperling reveal the functional alterations associated with healthy aging as well as MCI and AD.
Magnetic resonance spectroscopy (MRS) is a powerful non-invasive imaging technique that can provide crucial information about neurochemical changes in AD. Dr. Mandal and colleagues report that the identification of neurochemical changes in the brains of MCI and AD patients may provide a "signature" of early AD pathology, and may aid in diagnosing patients who are moving from MCI to more advanced AD.
Imaging is also used to examine the molecular and therapeutic effects of potential AD treatments. Liam Zaidel and colleagues found that patients treated with donepezil for mild cognitive symptoms had a significant increase in interhemispheric functional connectivity of the left and right dorsolateral prefrontal cortices. Giulia Liberati and colleagues describe a non-invasive brain-computer interface that can detect a patient's emotional and cognitive state. It could provide vital information on the effect of clinical drugs on brain function and cognition in patients with AD.
The issue also includes a thought-provoking argument from Edo Richard and colleagues calling for a paradigm shift in dementia research and biomarker development. Current biomarker research focuses on correlates of plaques and tangles, which are poor markers in older dementia subjects. The authors suggest that the acknowledgement that dementia in older subjects is different from dementia at a young age will lead to new approaches in biomarker development and research.
"Research is needed to understand which molecular, structural, and functional changes are causally related to the onset of AD," says Dr. Mandal. "This special issue aims to conceptualize more effective and reliable biomarkers for AD."
George Perry, PhD, Editor-in-Chief, Journal of Alzheimer's Disease, and Dean and Professor, College of Sciences, University of Texas at San Antonio, says, "The development of biomarkers to aid in early detection of the onset of AD is critical. This special issue will spur research into multi-model imaging based biomarker development for AD."
More information: "Biomarkers for Alzheimer's Disease Using Multi-Model Imaging Research," Guest Edited by Pravat K. Mandal. Journal of Alzheimer's Disease, Volume 31 (2012), Supplement 3.
Provided by IOS Press

Thursday, August 30, 2012

Low-calorie diet may not prolong life: study

A low-calorie diet boosts health but does not prolong life, at least not in rhesus monkeys, scientists reported Wednesday in a new study into a long-held link between food restriction and longevity.
30 aug 2012--Spanning 23 years, the research found monkeys that ate fewer calories than non-dieting counterparts were healthier but did not live any longer.
Rhesus monkeys are a preferred choice for lab study, as they are long-lived primates like humans—their average lifespan in captivity is 27 years and the usual maximum is 40 years.
The exceptionally long study, launched at the National Institute on Aging (NIA) in Maryland in 1987, saw monkeys of different ages fed a diet 30 percent lower in calories than others that followed a "normal," nutritious diet.
Animals in both groups lived on average longer than wild rhesus monkeys and were heavier too. None was malnourished, and they were given vitamin and mineral supplements, the researchers wrote in the journal Nature.
Those on the calorie-restricted diet had a lower incidence of diabetes, cardiovascular disease and cancer than the rest, and dieting males also had lower cholesterol.
"However, these effects did not translate directly to a beneficial effect in longevity," over the control monkeys, Rafael de Cabo of the NIA's Laboratory of Experimental Gerontology, told AFP.
The study was not designed to explain this phenomenon, and the authors say matching research to measure the impact of calorie restriction on longevity in humans was unlikely.
The findings seem to contradict those of other projects, including an ongoing study at the Wisconsin National Primate Research Centre (WNPRC) which has shown that rhesus monkeys placed on a restricted calorie diet lived longer.
These "mixed results" raised intriguing questions about the benefits of calorie restriction in primates, Steven Austad of the University of Texas' Barshop Institute for Longevity and Aging Studies wrote in a comment on the study, also published by Nature.
WNPRC senior scientist Ricki Colman told AFP there were many differences between the two studies that may explain the conflicting outcomes.
Importantly, the WNPRC control monkeys (those whose calorie intake was not restricted) were allowed free access to food, therefore mimicking a human in charge of his own nutrition intake.
In contrast, the NIA control group were given a limited amount of food, thus resembling an ideal human diet—which may explain why they lived as long as the monkeys on the low-calorie diet.
They were also given vitamin and mineral supplements and the WNPRC group not.
Comparing the two approaches, a compelling picture emerges, said De Cabo: a healthy diet does improve longevity, and eating less of it may slow the onset of some diseases but will not actually prolong life.
More information: DOI: 10.1038/nature11432

Tuesday, August 28, 2012

Healthy lifestyle reduces the risk of hypertension by two thirds

Healthy behaviours regarding alcohol, physical activity, vegetable intake and body weight reduce the risk of hypertension by two thirds, according to research presented at the ESC Congress today. The findings were presented by Professor Pekka Jousilahti from National Institute for Health and Welfare.
29 aug 2012--According to the World Health Organization, hypertension is the leading cause of mortality in the world, contributing annually to over 7 million deaths (about 15% of all deaths). Therefore, prevention of hypertension is essential to improving health and preventing morbidity and mortality, both in developing and developed countries.
The purpose of this study was to examine whether five major cardiovascular disease related lifestyle factors – smoking, alcohol consumption, physical activity, obesity and consumption of vegetables – predict the future increase of blood pressure and development of clinical hypertension, and need for antihypertensive drug treatment.
This large prospective population-based cohort study included 9,637 Finnish men and 11,430 women who were 25 to 74 years of age and free of hypertension during the baseline measurements (1982-2002). Healthy lifestyle factors were defined as: (1) not smoking, (2) alcohol consumption less than 50g per week, (3) leisure time physical activity at least 3 times per week, (4) daily consumption of vegetables, and (5) normal weight (BMI<25kg m2="m2" p="p">
Data on the development of hypertension during the follow-up period were obtained from the Social Insurance Institution of Finland register of people entitled to special reimbursement for antihypertensive drugs. During a mean follow-up of 16 years, 709 men and 890 women developed hypertension.
Smoking was omitted from the final analysis. Professor Jousilahti said: "Even though smoking is a major risk factor for cardiovascular disease, it was not associated with the development of hypertension in our analyses, which is in accordance with previous studies."
The four remaining healthy lifestyle factors were included in the analysis. Hazard ratios for hypertension associated with adherence to 0 (the reference group), 1, 2, 3, and 4 healthy lifestyle factors were calculated after adjusting for age, year of entering the study, education, and smoking.
The hazard ratios for hypertension associated with adherence to 0, 1, 2, 3, and 4 healthy lifestyle factors were 1.00, 0.74, 0.51, 0.34, and 0.33 for men, and 1.00, 0.89, 0.68, 0.41, and 0.37 for women. "The risk of hypertension was only one third among those having all four healthy lifestyle factors compared to those having none," said Professor Jousilahti. "Even having one to three healthy lifestyle factors reduced the risk of hypertension remarkably. For example having two healthy lifestyle factors reduced the risk of hypertension by nearly 50% in men and by more than 30% in women."
"Our analysis suggests that adherence to healthy lifestyle factors may have more of an impact on risk of hypertension in men than women," he added. "This could be because of the stronger association of obesity and alcohol consumption with the risk of hypertension in men than in women."
"Four modifiable lifestyle factors: alcohol consumption, physical activity, consumption of vegetables and keeping normal weight have a remarkable effect on the development of hypertension," said Professor Jousilahti. "Lifestyle modification has a huge public health potential to prevent hypertension. While our research suggests that lifestyle modification may produce greater reductions in hypertension in men than women, it also shows large benefits in women, and adherence to all four healthy lifestyle factors had a nearly similar effect in both sexes. Both men and women should take steps towards a healthier lifestyle to decrease their risk of hypertension."
He concluded: "Our study was focused on prevention of hypertension and therefore included subjects who did not have hypertension at baseline. But the results should apply to the treatment of patients with hypertension, who can reduce their blood pressure by modifying the four lifestyle factors alone, or by making these modifications while taking blood pressure lowering medication."
Provided by European Society of Cardiology

Mild cognitive decline in nearly half lacunar stroke patients

Mild cognitive decline in nearly half lacunar stroke patients

Mild cognitive impairment is present in nearly half of patients with lacunar stroke, according to a study published online Aug. 18 in the Annals of Neurology.
28 aug 2012—Mild cognitive impairment (MCI) is present in nearly half of patients with lacunar stroke, according to a study published online Aug. 18 in the Annals of Neurology.
Claudia Jacova, Ph.D., of the University of British Columbia in Vancouver, Canada, and associates conducted a study to characterize, and estimate the prevalence of, neuropsychological impairment in 1,636 English-speaking lacunar stroke patients. Using published norms, raw scores were converted to z scores. Participants underwent neuropsychological testing at baseline and those with impairment (z score of ≤1.5) in memory and/or non-memory domains were classified as having MCI.
The researchers found that the average z scores at baseline testing were below zero. The largest deficits were seen in measures of episodic memory (range of means, −0.65 to −0.92), verbal fluency (mean, −0.89), and motor dexterity (mean, −2.5). Of the participants, 47 percent were classified as having MCI, which included 36 percent amnestic, 37 percent amnestic multidomain, and 28 percent non-amnestic. Forty-one percent of those with Rankin score of 0 to 1 and Barthel score of 100 percent had MCI.
"In this large, well-characterized cohort of lacunar stroke patients, MCI was present in nearly half, including many with minimal or no physical disabilities," the authors write. "Cognitive dysfunction in lacunar stroke patients may commonly be overlooked in clinical practice but may be as important as motor and sensory sequelae."
Study medication was donated by Sanofi/BMS USA.

Monday, August 27, 2012

Women with Alzheimer's deteriorate faster than men

Women with Alzheimer's show worse mental deterioration than men with the disease, even when at the same stage of the condition, according to researchers from the University of Hertfordshire.
27 aug 2012--In the paper published in the Journal of Clinical and Experimental Neuropsychology, the researchers discovered that men with Alzheimer's consistently and significantly performed better than women with the disease across the five cognitive areas they examined. Most remarkably, the verbal skills of women with Alzheimer's are worse when compared to men with the disease, which is a striking difference to the profile for the healthy population where females have a distinct advantage.
The researchers led by Professor Keith Laws completed a meta-analysis of neurocognitive data from fifteen published studies, which revealed a consistent male advantage on verbal and visuospatial tasks, and tests of both episodic1 and semantic2 memory.
Keith Laws, Professor of psychology, said: "Unlike mental decline associated with normal aging, something about Alzheimer's specifically disadvantages women.
"There has been some previous, but limited, evidence that females with Alzheimer's deteriorate faster than males in the earlier stages of the disease. And possible explanations are for a hormonal influence, possibly due to oestrogen loss in women or perhaps a greater cognitive reserve in males which provides protection against the disease process. But further studies to examine sex differences with the disease are needed to provide greater clarity on these issues."
Further analysis of the study data showed that age, education level and dementia severity did not explain the advantage that men with the disease have over women with the disease.
Alzheimer's disease, a common progressive condition affecting memory, thinking, behaviour and emotion, is the most common form of dementia. Alzheimer's Disease International estimates that there are currently thirty million people in the world with dementia, with 4.6 million new cases every year. The incidence of Alzheimer's is greater among women than men, with the difference increasing with age.
Provided by University of Hertfordshire

Sunday, August 26, 2012

Global study suggests need for strategies to combat unhealthy lifestyles among the poor and the rich

Healthy foods such as fruits and vegetables, proteins and total fats are consumed more often by the wealthy while poorer people consume more carbohydrates, says a new study involving people from 17 countries.
26 aug 2012--The Prospective Urban Rural Epidemiology (PURE) study involving 154,000 individuals from 628 communities reported on the patterns of diet, physical activity and smoking, was presented at the European Society of Cardiology 2012 Congress on Sunday, Aug. 26, 2012.
The study found individuals who were poor, or from poorer countries were more active chiefly because of higher energy expenditure in jobs, at home, and during transportation.
The markedly lower level of obligatory physical activity was not compensated for by higher levels of recreational physical activity in richer countries or richer individuals. Those who were rich and those in richer countries quit smoking much more often so that rates of smoking was lower in the wealthier individuals and wealthier countries.
"Policies to prevent cardiovascular disease need to focus on different aspects of lifestyle among the rich versus the poor and between rich and poor countries," said professor Salim Yusuf of the Population Health Research Institute, McMaster University and Hamilton Health Sciences and principal investigator of the study.
The study was conducted in 17 countries and coordinated worldwide by the Population Health Research Institute and supported by the Canadian Institutes of Health Research, the Indian Council of Medical Research, several other peer review organizations and pharmaceutical companies.
"These results provide new insights into the need to customize prevention policies differently for the rich and the poor and for countries at different economic levels," said professor David Wood of the University of London, UK and an expert in cardiovascular disease prevention.
Provided by McMaster University

Saturday, August 25, 2012

Obesity, metabolic factors linked to faster cognitive decline

People who are obese and also have high blood pressure and other risk factors called metabolic abnormalities may experience a faster decline in their cognitive skills over time than others, according to a study published in the August 21, 2012, print issue of Neurology, the medical journal of the American Academy of Neurology.
25 aug 2012--Metabolic abnormality was defined as having two or more of the following risk factors: high blood pressure or taking medication for it; low HDL or "good" cholesterol; high blood sugar or taking diabetes medication; and high triglycerides (a type of fat found in the blood) or taking medication to lower cholesterol.
The study involved 6,401 people with an average age 50 at the start of the study. Information on body mass index (BMI) and the risk factors was gathered at the beginning of the study. The participants took tests on memory and other cognitive skills three times over the next 10 years.
A total of 31 percent of the participants had two or more metabolic abnormalities. Nine percent were obese and 38 percent were overweight. Of the 582 obese people, 350, or 60 percent, met the criteria for metabolic abnormality. The metabolically normal obese individuals also experienced more rapid decline.
Over the 10 years of the study, people who were both obese and metabolically abnormal experienced a 22.5 percent faster decline on their cognitive test scores than those who were of normal weight without metabolic abnormalities.
"More research is needed to look at the effects of genetic factors and also to take into account how long people have been obese and how long they have had these metabolic risk factors and also to look at cognitive test scores spanning adulthood to give us a better understanding of the link between obesity and cognitive function, such as thinking, reasoning and memory," said study author Archana Singh-Manoux, PhD, of INSERM, the French research institute in Paris and University College London in England.
Singh-Manoux said the study also provides evidence against the concept of "metabolically healthy obesity" that has suggested that obese people without metabolic risk factors do not show negative cardiac and cognitive results compared to obese people with metabolic risk factors.
Provided by American Academy of Neurology

Friday, August 24, 2012

First evidence from humans on how alcohol may boost risk of cancer

Almost 30 years after discovery of a link between alcohol consumption and certain forms of cancer, scientists are reporting the first evidence from research on people explaining how the popular beverage may be carcinogenic. The results, which have special implications for hundreds of millions of people of Asian descent, were reported here today at the 244th National Meeting & Exposition of the American Chemical Society.
24 aug 2012--Silvia Balbo, Ph.D., who led the study, explained that the human body breaks down, or metabolizes, the alcohol in beer, wine and hard liquor. One of the substances formed in that breakdown is acetaldehyde, a substance with a chemical backbone that resembles formaldehyde. Formaldehyde is a known human carcinogen. Scientists also have known from laboratory experiments that acetaldehyde can cause DNA damage, trigger chromosomal abnormalities in cell cultures and act as an animal carcinogen.
"We now have the first evidence from living human volunteers that acetaldehyde formed after alcohol consumption damages DNA dramatically," Balbo said. She is a research associate in the laboratory of Stephen Hecht, Ph.D., a noted authority on cancer prevention at the University of Minnesota. "Acetaldehyde attaches to DNA in humans ― to the genetic material that makes up genes - in a way that results in the formation of a 'DNA adduct.' It's acetaldehyde that latches onto DNA and interferes with DNA activity in a way linked to an increased risk of cancer."
Balbo pointed out that people have a highly effective natural repair mechanism for correcting the damage from DNA adducts. Most people thus are unlikely to develop cancer from social drinking, although alcohol is associated with a risk of other health problems and accidents. In addition, most people have an enzyme called alcohol dehydrogenase, which quickly converts acetaldehyde to acetate, a relatively harmless substance.
However, about 30 percent of people of Asian descent ― almost 1.6 billion people ― have a variant of the alcohol dehydrogenase gene and are unable to metabolize alcohol to acetate. That genetic variant results in an elevated risk of esophageal cancer from alcohol drinking. Native Americans and native Alaskans have a deficiency in the production of that same enzyme.
To test the hypothesis that acetaldehyde causes DNA adducts to form in humans, Balbo and colleagues gave 10 volunteers increasing doses of vodka (comparable to one, two and three drinks) once a week for three weeks. They found that levels of a key DNA adduct increased up to 100-fold in the subjects' oral cells within hours after each dose, then declined about 24 hours later. Adduct levels in blood cells also rose.
"These findings tell us that alcohol, a lifestyle carcinogen, is metabolized into acetaldehyde in the mouth, and acetaldehyde is forming DNA adducts, which are known major players in carcinogenesis," said Balbo.
Provided by American Chemical Society

Thursday, August 23, 2012

Many medications for elderly are prescribed inappropriately

Approximately one in five prescriptions to elderly people is inappropriate, according to a study published Aug. 22 in the open access journal PLOS ONE.
23 aug 2012--The authors of the study, led by Dedan Opondo of the Academic Medical Center in Amsterdam, conducted a systematic review of English-language studies of medication use in the elderly and found that the median rate of inappropriate prescriptions was 20.5%.
Some of the medications with the highest rates of inappropriate use were the antihistamine diphenhydramine, the antidepressant amitriptyline, and the pain reliever propoxyphene.
More information: Opondo D, Eslami S, Visscher S, de Rooij SE, Verheij R, et al. (2012) Inappropriateness of Medication Prescriptions to Elderly Patients in the Primary Care Setting: A Systematic Review. PLoS ONE 7(8): e43617.doi:10.1371/journal.pone.0043617
Provided by Public Library of Science

Wednesday, August 22, 2012

Common treatment for mild hypertension challenged

Common treatment for mild hypertension challenged
Doctors often prescribe drugs for people with mild high blood pressure with the hope of preventing cardiovascular disease (CVD). However, a new review from The Cochrane Library has found that this treatment does not reduce death rates, heart attacks or strokes.
22 aug 2012--Current guidelines in the U.S., Europe and Canada support drug treatment for people with mild hypertension, the majority of hypertension patients, even when they have no history of cardiovascular events. Consequences of such treatment include potential side effects, cost, and inconvenience.
“In people with no cardiovascular events and mild elevations in resting blood pressure ( 140 – 159/90 – 89 mmHg), it is not known whether the benefits of drug therapy exceed the harms,” said Diana Diao, M.D., resident physician at the University of British Columbia. To answer this concern, the research team combined findings from 4 clinical trials done between 1976 and 2000, which together included data on 8,912 study participants followed for up to 5 years.
The researchers found that 400 people with mild hypertension would have to be treated for five years to prevent one death and 128 people would have to be treated for five years to prevent one cardiovascular event, such as aheart attack. However, treated patients had a nine percent risk of an adverse effect that would force them to stop taking the prescribed drug.
These findings might prompt physicians to emphasize non-drug treatment approaches, including changes in diet and exercise, said the authors. They note that many physicians have been prescribing medications for patients with mild hypertension thinking that the approach is based on evidence from randomized clinical trials.
Luci Belnick, M.D., an Orlando-based physician with over 25 years experience questioned the new findings’ validity. She said that the patients should have been followed for longer than five years as that is a short time in terms of accumulating vascular damage due to hypertension; that the studies included concerned many drugs that are now seldom used; and that the studies included too few African-Americans, who have elevated risks of kidney damage and strokes from even mild hypertension.
“Before you diagnose and treat a patient, it’s important to make sure that they really have hypertension, that their particular patient group has a meaningful risk of hypertension complications, even long-term, and that you select a medication with a known benefit in that group,” she said.
More information: Diao D, Wright JM, Cundiff DK, Gueyffier F. Pharmacotherapy for mild hypertension. Cochrane Database of Systematic Reviews 2012, Issue 8. Art. No.: CD006742. DOI: 10.1002/14651858.CD006742.pub2
Provided by Center for Advanced Healing

Tuesday, August 21, 2012

Cocoa compounds may reduce blood pressure

Compounds in cocoa may help to reduce blood pressure, according to a new systematic review in The Cochrane Library. The researchers reviewed evidence from short-term trials in which participants were given dark chocolate or cocoa powder daily and found that their blood pressure dropped slightly compared to a control group.
21 aug 2012--Cocoa contains compounds called flavanols, thought to be responsible for the formation of nitric oxide in the body. Nitric oxide causes blood vessel walls to relax and open wider, thereby reducing blood pressure. The link between cocoa and blood pressure stems from the discovery that the indigenous people of San Blas Island in Central American, who drink flavanol-rich cocoa drinks every day, have normal blood pressure regardless of age. However, flavanol concentrations in cocoa and chocolate products vary according to cocoa processing procedures and types of chocolate, so it is difficult to establish the optimal dosage for an effect.
To investigate the effect of flavanols on blood pressure, the researchers reviewed data from trials in which people consumed dark chocolate or cocoa powder containing between 30-1080 mg of flavanols in 3-100 g of chocolate each day. Altogether, 856 people were involved in 20 trials lasting 2-8 weeks, or in one case, 18 weeks. Flavanol-rich chocolate or cocoa powder reduced blood pressure on average by 2-3 mm Hg.
"Although we don't yet have evidence for any sustained decrease in blood pressure, the small reduction we saw over the short term might complement other treatment options and might contribute to reducing the risk of cardiovascular disease," said lead researcher Karin Ried of the National Institute of Integrative Medicine in Melbourne, Australia, who worked with colleagues at the University of Adelaide.
In a subset of trials, when chocolate or cocoa powder was compared to flavanol-free-products as controls, the beneficial effects were more pronounced (3-4 mm Hg), whereas the researchers found no significant effect on blood pressure in the second subset with low-flavanol products as control. It is possible that low-flavanol products also have a small effect on blood pressure, so that it was harder to observe differences between high and low-flavanol products in these trials. However, results of these subsets of trials may have been influenced by trial length and blinding of participants, as trials using flavanol-free control products tended to be of shorter duration with participants knowing their allocated group.
"We'll also need to see long term trials, including effects on the risk of stroke and cardiovascular disease, before we can come to conclusions regarding clinical outcomes and potential side effects of long-term consumption," said Ried. "These trials should use flavanol-free products in the control groups to eliminate any potential effects of low-dose flavanol on blood pressure."
More information: Ried K, Sullivan TR, Fakler P, Frank OR, Stocks NP. Effect of cocoa on blood pressure. Cochrane Database of Systematic Reviews 2012, Issue 8. Art. No.: CD008893. DOI: 10.1002/14651858.CD008893.pub2
Provided by Wiley

Monday, August 20, 2012

Egg yolk consumption almost as bad as smoking when it comes to atherosclerosis

Newly published research led by Dr. David Spence of Western University, Canada, shows that eating egg yolks accelerates atherosclerosis in a manner similar to smoking cigarettes. Surveying more than 1200 patients, Dr. Spence found regular consumption of egg yolks is about two-thirds as bad as smoking when it comes to increased build-up of carotid plaque, a risk factor for stroke and heart attack. The research is published online in the journalAtherosclerosis.
20 aug 2012--Atherosclerosis, also called coronary artery disease, is a disorder of the arteries where plaques, aggravated by cholesterol, form on the inner arterial wall. Plaque rupture is the usual cause of most heart attacks and many strokes. The study looked at data from 1231 men and women, with a mean age of 61.5, who were patients attending vascular prevention clinics at London Health Sciences Centre's University Hospital. Ultrasound was used to establish a measurement of total plaque area and questionnaires were filled out regarding their lifestyle and medications including pack-years of smoking (number of packs per day of cigarettes times the number of years), and the number of egg yolks consumed per week times the number of years consumed (egg yolk-years).
The researchers found carotid plaque area increased linearly with age after age 40, but increased exponentially with pack-years of smoking and egg yolk-years. In other words, compared to age, both tobacco smoking and egg yolk consumption accelerate atherosclerosis. The study also found those eating three or more yolks a week had significantly more plaque area than those who ate two or fewer yolks per week.
"The mantra 'eggs can be part of a healthy diet for healthy people' has confused the issue. It has been known for a long time that a high cholesterol intake increases the risk of cardiovascular events, and egg yolks have a very high cholesterol content. In diabetics, an egg a day increases coronary risk by two to five-fold," says Dr. Spence, a Professor of Neurology at Western's Schulich School of Medicine & Dentistry and the Director of its Stroke Prevention and Atherosclerosis Research Centre (SPARC) at the Robarts Research Institute. "What we have shown is that with aging, plaque builds up gradually in the arteries of Canadians, and egg yolks make it build up faster - about two-thirds as much as smoking. In the long haul, egg yolks are not okay for most Canadians."
Dr. Spence adds the effect of egg yolk consumption over time on increasing the amount of plaque in the arteries was independent of sex, cholesterol, blood pressure, smoking, body mass index and diabetes. And while he says more research should be done to take in possible confounders such as exercise and waist circumference, he stresses that regular consumption of egg yolk should be avoided by persons at risk of cardiovascular disease.
Provided by University of Western Ontario

Sunday, August 19, 2012

Mediterranean diet enriched with olive oil may protect bone

A study to be published in the Endocrine Society's Journal of Clinical Endocrinology and Metabolism (JCEM) shows consumption of a Mediterranean diet enriched with olive oil for two years is associated with increased serum osteocalcin concentrations, suggesting a protective effect on bone.
19 aug 2012--Age-related bone mass loss and decreased bone strength affects women and men alike are an important determinant of osteoporosis and fracture risk. Studies have shown that the incidence of osteoporosis in Europe is lower in theMediterranean basin. The traditional Mediterranean diet, rich in fruits and vegetables, with a high intake of olives and olive oil could be one of the environmental factors underlying this difference.
"The intake of olive oil has been related to the prevention of osteoporosis in experimental and in vitro models," said José Manuel Fernández-Real, MD, PhD, of Hospital Dr. Josep Trueta in Girona, Spain and lead author of the study. "This is the first randomized study which demonstrates that olive oil preserves bone, at least as inferred by circulating bone markers, in humans."
The participants in this study were 127 community-dwelling men aged 55 to 80 years randomly selected from one of the Prevencion con Dieta Mediterranea (PREDIMED) study centers who had at least two years of follow-up. The PREDIMED study is a large, parallel group, randomized, controlled trial aimed to assess the effect of the Mediterranean diet on the prevention of cardiovascular diseases.
For this study, subjects were elderly without prior cardiovascular disease but having a diagnosis of type 2 diabetes or harboring at least three cardiovascular risk factors, namely hypertension, dyslipidemia, or a family history of premature cardiovascular disease. Participants were randomly assigned to three intervention groups: Mediterranean diet with mixed nuts, Mediterranean diet with virgin olive oil, and a low-fat diet.
Biochemical measurements of osteocalcin, glucose, total cholesterol, HDL-cholesterol and triglycerides were performed at baseline and after two year follow-up on fasting blood samples. Researchers found that only consumption of the Mediterranean diet with olive oil was associated with a significant increase in the concentrations of total osteocalcin and other bone formation markers. There were also no significant changes in serum calcium in subjects taking olive oil whereas serum calcium decreased significantly in the other two groups.
"It's important to note that circulating osteocalcin was associated with preserved insulin secretion in subjects taking olive oil," added Fernández-Real. "Osteocalcin has also been described to increase insulin secretion in experimental models."
More information: The article, "A Mediterranean Diet Enriched with Olive Oil is Associated with Higher Serum Total Osteocalcin Levels in Elderly Men at High Cardiovascular Risk," will appear in the October 2012 issue of JCEM.
Provided by The Endocrine Society

Saturday, August 18, 2012

Fit over-fifties are lowering heart disease odds

Fit over-fifties are lowering heart disease odds
18 aug 2012-- Even a moderate increase in exercise when you are in your fifties can help your heart health according to a study published today by researchers from UCL Epidemiology and Public Health.
The study shows inflammation in the body – which is thought to contribute to heart disease – remains lower in people in the transition to retirement who embrace an active lifestyle, with at least 2.5 hours a week of moderate physical activity (enough to raise your heart rate), than in those who stay less active. This is great news for retirees, who often celebrate their new-found freedom with a whole range of activities, from gardening to DIY to countryside walks.
In the study, over 4,000 people from the Whitehall II cohort were quizzed on their exercise routines and had levels of inflammation measured to gauge their heart health over a ten year period.
Dr Mark Hamer, UCL Epidemiology and Public Health, said: “Previous studies looking at how exercise protects the heart have only been carried out for short periods of time. Our ten year study reveals for the first time the long-term effects of leading an active lifestyle on inflammation and heart disease.
“It’s great news that people who spring into retirement and become more active are actually making a big difference in helping their hearts grow old healthily.”
British Heart Foundation Senior Cardiac Nurse Maureen Talbot said: “Donning your gardening gloves, or picking up a paint brush, can still go a long way to help look after your heart health, as exercise can have a big impact on how well your heart ages.
“This research highlights the positive impact changing your exercise habits can have on the future of your heart health – and that it’s never too late to re-energise your life. However it’s important not to wait until you retire to get off the couch, as being active for life is a great way to keep your heart healthy.”
Jack Oldman, aged 87, who plays table tennis through the BHF Hearty Lives Hull project, said: “I play at my club twice a week and still compete in my local league. If I couldn’t play sport I don’t know what I‘d do.
“The worst thing you could do when you retire is to sit down and watch telly all day. I keep busy with sports and my vegetable patch and it seems to be keeping me going well - doctors have told me I’ve got a great heart for my age.”
Provided by University College London

Friday, August 17, 2012

Resistance to dementia may run in the family

People who are free of dementia and have high levels of a protein that indicates the presence of inflammation have relatives who are more likely to avoid the disease as well, according to a new study published in the August 15, 2012, online issue of Neurology, the medical journal of the American Academy of Neurology.
17 aug 2012--"In very elderly people with good cognition, higher levels of C-reactive protein, which is related to inflammation, are associated with better memory," said study author Jeremy M. Silverman, PhD, with Mount Sinai School of Medicine in New York. "Our results found that the higher the level of this protein in the study participant, the lower the risk for dementia in their parents and siblings."
For the study, researchers identified 277 male veterans age 75 and older and free of dementia symptoms. They were given a test that measured levels of the protein. Next, the group was interviewed about 1,329 parents and siblings and whether they had dementia. A total of 40 relatives from 37 families had dementia. A secondary, independent group of 51 men age 85 and older with no dementia symptoms were given an interview about 202 relatives for dementia. Nine of the relatives had dementia.
Study investigators found that participants who had higher amounts of the protein were more than 30 percent less likely to have relatives with dementia. Similar results were found in the secondary group. Since the protein levels were not associated with years of education, marital status, occupation and physical activity, these factors could not account for the lower risks seen.
"This protein is related to worse cognition in younger elderly people. Thus, for very old people who remain cognitively healthy, those with a high protein level may be more resistant to dementia," said Silverman. "Our study shows that this protection may be passed on to immediate relatives."
Provided by American Academy of Neurology

Thursday, August 16, 2012

Study adds to evidence daily aspirin linked to lower cancer mortality

A large new observational study finds more evidence of an association between daily aspirin use and modestly lower cancer mortality, but suggests any reduction may be smaller than that observed in a recent analysis. The study, appearing early online in the Journal of the National Cancer Institute (JNCI), provides additional support for a potential benefit of daily aspirin use for cancer mortality, but the authors say important questions remain about the size of the potential benefit.
16 aug 2012--A recent analysis pooling results from existing randomized trials of daily aspirin for prevention of vascular events found an estimated 37% reduction in cancer mortality among those using aspirin for five years or more. But uncertainty remains about how much daily aspirin use may lower cancer mortality, as the size of this pooled analysis was limited and two very large randomized trials of aspirin taken every other day found no effect on overall cancer mortality.
For the current study, American Cancer Society researchers led by Eric J. Jacobs, Ph.D., analyzed information from 100,139 predominantly elderly participants in the Cancer Prevention Study II Nutrition Cohort who reported aspirin use onquestionnaires, did not have cancer at the start of the study, and were followed for up to 11 years. They found daily aspirin use was associated with an estimated 16% lower overall risk of cancer mortality, both among people who reported taking aspirin daily for at least five years and among those who reported shorter term daily use. The lower overall cancer mortality was driven by about 40% lower mortality from cancers of the gastrointestinal tract (such as esophageal, stomach, and colorectal cancer) and about 12% lower mortality from cancers outside the gastrointestinal tract.
The reduction in cancer mortality observed in the current study is considerably smaller than the 37% reduction reported in the recent pooled analysis of randomized trials. The authors note that their study was observational, not randomized, and therefore could have underestimated or overestimated potential effects on cancer mortality if participants who took aspirin daily had different underlying risk factors for fatal cancer than those who did not. However, the study's large size is a strength in determining how much daily aspirin use might lower cancer mortality.
"Expert committees that develop clinical guidelines will consider the totality of evidence about aspirin's risks and benefits when guidelines for aspirin use are next updated," said Dr. Jacobs. "Although recent evidence about aspirin use and cancer is encouraging, it is still premature to recommend people start taking aspirin specifically to prevent cancer. Even low-dose aspirin can substantially increase the risk of serious gastrointestinal bleeding. Decisions about aspirin use should be made by balancing the risks against the benefits in the context of each individual's medical history. Any decision about daily aspirin use should be made only in consultation with a health care professional."
More information: Daily Aspirin Use and Cancer Mortality in a Large US Cohort, Eric J. Jacobs, Christina C. Newton, Susan M. Gapstur, Michael J. Thun. Journal of the National Cancer Institute; Published early online: August 10, 2012,DOI:10.1093/jnci/djs318
Provided by American Cancer Society

Wednesday, August 15, 2012

Thinking about giving, not receiving, motivates people to help others

 We’re often told to ‘count our blessings’ and be grateful for what we have. And research shows that doing so makes us happier. But will it actually change our behavior towards others?
15 aug 2012--A new study published in Psychological Science, a journal of the Association for Psychological Science, suggests that thinking about what we’ve given, rather than what we’ve received, may lead us to be more helpful toward others.
Researchers Adam Grant of The Wharton School of the University of Pennsylvania and Jane Dutton of The Ross School of Business at the University of Michigan wanted to understand how reflection, in the form of expressive writing, might influence prosocial behavior. They observed that when we reflect on what we’ve received from another person, we might feel an obligation to help that person, but the motivation to help doesn’t necessarily extend to other people. And reflecting on what we’ve received from others may even cause us to feel dependent and indebted.
The researchers wondered whether thinking about times when we have given to others might be more effective in promoting helping. They hypothesized that reflecting on giving could lead a person to see herself as a benefactor, strengthening her identity as a caring, helpful individual and motivating her to take action to benefit others.
In their first experiment, the researchers studied fundraisers whose job was to solicit alumni donations to support various programs at a university. The researchers randomly split the fundraisers into two groups: one group wrote journal entries about recent experiences of feeling grateful for receiving a benefit and the other group wrote journal entries about recent experiences in which they made a contribution that enabled other people to feel grateful.
Grant and Dutton then measured how many calls each fundraiser made per hour in the two weeks before and the two weeks after the week that they spent journaling. Because the fundraisers were paid a fixed hourly rate, with no fundraising goals or incentives, the number of calls they made reflected voluntary effort to help raise funds for the university.
As the researchers hypothesized, the fundraisers who wrote about giving for just two or three days increased their hourly calls by more than 29% in the following two weeks. The fundraisers who wrote about receiving, however, showed no change in the number hourly calls made.
In a second experiment, the researchers randomly assigned college students to one of three groups, requiring them to list three ways they had recently given help, list three ways they had recently received help, or list three different foods they had eaten in the last week.
When the participants came to the university’s behavioral lab a few weeks later to pick up their payment for participating in the study, they were given a form describing the March 11, 2011 earthquake and tsunami in Japan. On the form, the participants were asked whether they would like to donate any portion of their $5 payment to an earthquake relief fund.
Overall, 26% of the participants donated some amount of money. Similar to the results of the first experiment, participants who reflected on giving were significantly more likely to donate (46.15%) than those in either the beneficiary (21.43%) or control condition (13.33%).
Grant and Dutton believe that the findings from these two experiments have important real-world implications.
“Helping, giving, volunteering, and other actions undertaken to benefit others play a critical role in protecting health, promoting education, fighting poverty and hunger, and providing disaster relief,” the researchers write.
This new research suggests that self-reflection about giving can be a powerful tool for motivating helping and volunteering behaviors that benefit individuals and communities. When we reflect on positive experiences, it may be worthwhile to think about what we’ve given to others—not only what we’ve received.
Provided by Association for Psychological Science

Tuesday, August 14, 2012

Should doctors treat lack of exercise as a medical condition? Mayo expert says 'yes'

A sedentary lifestyle is a common cause of obesity, and excessive body weight and fat in turn are considered catalysts for diabetes, high blood pressure, joint damage and other serious health problems. But what if lack of exercise itself were treated as a medical condition? Mayo Clinic physiologist Michael Joyner, M.D., argues that it should be. His commentary is published this month in The Journal of Physiology.
14 aug 2012--Physical inactivity affects the health not only of many obese patients, but also people of normal weight, such as workers with desk jobs, patients immobilized for long periods after injuries or surgery, and women on extended bed rest during pregnancies, among others, Dr. Joyner says. Prolonged lack of exercise can cause the body to become deconditioned, with wide-ranging structural and metabolic changes: the heart rate may rise excessively during physical activity, bones and muscles atrophy, physical endurance wane, and blood volume decline.
When deconditioned people try to exercise, they may tire quickly and experience dizziness or other discomfort, then give up trying to exercise and find the problem gets worse rather than better.
"I would argue that physical inactivity is the root cause of many of the common problems that we have," Dr. Joyner says. "If we were to medicalize it, we could then develop a way, just like we've done for addiction, cigarettes and other things, to give people treatments, and lifelong treatments, that focus on behavioral modifications and physical activity. And then we can take public health measures, like we did for smoking, drunken driving and other things, to limit physical inactivity and promote physical activity."
Several chronic medical conditions are associated with poor capacity to exercise, including fibromyalgia, chronic fatigue syndrome and postural orthostatic tachycardia syndrome, better known as POTS, a syndrome marked by an excessive heart rate and flu-like symptoms when standing or a given level of exercise. Too often, medication rather than progressive exercise is prescribed, Dr. Joyner says.
Texas Health Presbyterian Hospital Dallas and University of Texas Southwestern Medical Center researchers found that three months of exercise training can reverse or improve many POTS symptoms, Dr. Joyner notes. That study offers hope for such patients and shows that physicians should consider prescribing carefully monitored exercise before medication, he says.
If physical inactivity were treated as a medical condition itself rather than simply a cause or byproduct of other medical conditions, physicians may become more aware of the value of prescribing supported exercise, and more formal rehabilitation programs that include cognitive and behavioral therapy would develop, Dr. Joyner says.
For those who have been sedentary and are trying to get into exercise, Dr. Joyner advises doing it slowly and progressively.
"You just don't jump right back into it and try to train for a marathon," he says. "Start off with achievable goals and do it in small bites."
There's no need to join a gym or get a personal trainer: build as much activity as possible into daily life. Even walking just 10 minutes three times a day can go a long way toward working up to the 150 minutes a week of moderate physical activity the typical adult needs, Dr. Joyner says.
Provided by Mayo Clinic

Friday, August 10, 2012

Why do older adults display more positive emotion? It might have to do with what they're looking at

Research has shown that older adults display more positive emotions and are quicker to regulate out of negative emotional states than younger adults. Given the declines in cognitive functioning and physical health that tend to come with age, we might expect that age would be associated with worse moods, not better ones.
09* auig 2012--So what explains older adults' positive mood regulation?
In a new article in the August issue of Current Directions in Psychological Science, a journal of the Association for Psychological Science, researcher Derek Isaacowitz of Northeastern University explores positive looking as one possible explanation: older adults may be better at regulating emotion because they tend to direct their eyes away from negative material or toward positive material.
Isaacowitz presents evidence indicating that, compared to younger adults, older adults prefer positive looking patterns and they show the most positive looking when they are in bad moods, even though this is when younger adults show the most negative looking.
Research conducted by Isaacowitz and colleagues indicates that there is actually a causal relationship between positive looking and mood: for adults with good attentional abilities, positive looking patterns can help to regulate their mood.
Although older adults prefer to focus on positive stimuli, the research shows that they aren't necessarily missing any salient or important information.
Provided by Association for Psychological Science

Thursday, August 09, 2012

Delirium increases risk of developing new dementia eight-fold in older patients

Older people who have experienced episodes of delirium are significantly more likely to develop dementia, according to new research. The study is published in the journal Brain today.
09 aug 2012--When in hospital, older people sometimes become acutely confused and disorientated. This condition, known as delirium, affects at least 15 per cent of older people in hospitals and has long thought to be simply a temporary side effect of other illness (such as an infection, a reaction to a medication or an operation). However, the new research shows that episodes of delirium can have long term effects - increasing the future risk of dementia eight-fold.
Dr Daniel Davis, lead author of the paper from the University of Cambridge, said: "This means that delirium, or the acute causes of delirium, could be a newly discovered cause of dementia. This is important, because although delirium is extremely common, less than a quarter of cases are actually diagnosed in hospitals."
Scientists at the University of Cambridge and the University of Eastern Finland recruited 553 people aged 85 and over, and assessed their memory and thinking over 10 years. Of the patients who had previously experienced at least one episode of delirium prior to the study, 77 per cent also had dementia. In comparison, only 33 per cent of the patients who had no previous history of delirium had dementia. They also recorded the number of episodes of delirium throughout the study.
In people without pre-existing dementia, experiencing delirium resulted in an eight-fold increase in the risk of dementia. In individuals with existing dementia, delirium was associated with an acceleration of dementia severity, loss of independence in physical functioning, and higher mortality.
Dr Davis added: "Worsening confusion and disorientation in older persons does not attract much attention among clinical staff and many believe that delirium is simply an inconvenient consequence of illness. However, this research suggests the possibility that delirium, or the problems giving rise to delirium, may be actually causing  damage.
"Because some delirium is preventable, it is plausible that delirium prevention may lead to dementia prevention. We now urgently need to test if better delirium care can prevent dementia, or prevent further decline in patients who already have dementia."
The Wellcome Trust-funded study also found, for the first time, that there may be differences in the brains of people who have had delirium compared to those without delirium. Dementia is known to result from a several different pathological processes (e.g. accumulation of abnormal proteins, or blockages in blood vessels). However, this study found that when individuals had both delirium and dementia, these standard neuropathological markers were not enough to explain the dementia. This raises the important possibility that dementia occurring after delirium had alternative pathological processes causing the dementia.
Professor Clive Ballard, Director of Research at Alzheimer's Society, said: "Scientists have believed there could be a link between delirium and dementia for many years. This robust study adds weight to this knowledge. With hospitalisation thought to be a cause of delirium, it's vital that healthcare professionals recognise the potential long term impact of delirium and are aware that older people who experience episodes could be susceptible to developing dementia."
Dr Karin Neufeld, President-Elect of the American Delirium Society and Director of General Hospital Psychiatry at Johns Hopkins Hospital, commented: "Research on delirium has repeatedly highlighted the association between cognitive impairment, and dementia and the development of delirium in the hospital setting in elderly individuals.
"This important research suggests that preventing delirium might be an important way to decrease the onset and progression of dementia in some people. The implication is that we, as healthcare professionals, need to redouble our efforts to detect and prevent delirium in hospitalised patients."
More information: The paper 'Delirium is a strong risk factor for dementia in the oldest old: a population-based cohort study' will be published in the 09 August 2012 edition of Brain.
Provided by University of Cambridge

Wednesday, August 08, 2012

Balance and strength training can prevent falls in older people

Balance and strength training is known to reduce falls in older adults. However, less than 10% of older people routinely engage in strength training and it is likely that this is much lower for activities that challenge balance.
08 aug 2012--It has been suggested that integrating exercise into everyday activities may help people stick to it, but this approach has never been investigated in frail older people at risk of falls.
So a team of researchers at the University of Sydney designed and tested the Lifestyle integrated Functional Exercise (LiFE) programme, which involves embedding balance and lower limb strength training into daily routines, such as walking, stepping over objects and moving from sitting to standing.
They then compared this approach with a structured exercise programme (performed three times a week using ankle cuff weights) and gentle 'sham' exercises that acted as the study control.
They recruited 317 men and women aged 70 or older, living in the community and having two or more falls, or one injurious fall, in the past year.
Participants were split into the three treatment arms and recorded any falls over 12 months using daily calendars. Other measures like static and dynamic balance, ankle, knee and hip strength, daily living activities, and quality of life were also measured recognised scales.
They found a significant (31%) reduction in the rate of falls for participants in the LiFE programme compared with the control group. The overall incidence of falls in the LiFE programme was 1.66 per person years, compared with 1.90 in the structured programme and 2.28 in the control group.
There was a non-significant reduction in the rate of falls for participants in the structured programme compared to the control group.
Compared with control patients, LiFE participants showed improvements in both static and dynamic balance, ankle strength, and in function and participation in daily life, suggesting that this programme improves both fall risk and frailty.
Adherence was significantly better in the LiFE programme and control group compared with the structured exercise programme.
The authors conclude that the LiFE programme "provides an alternative to traditional exercise for older people to reduce falls, to improve function in doing activities and to enhance participation in daily life."
In an accompanying editorial, Professor Meg Morris from the University of Melbourne says that for fall prevention programmes in older people to be effective, "therapeutic exercises, education, and physical activities need to be sustainable, enjoyable, and effective over the long term."
She adds: "The belief that falls should be accepted and tolerated as part of the ageing process is a myth that needs dispelling. Many falls can and should be prevented."
Provided by British Medical Journal