New C. diff treatment reduces recurrent infections by 40 percent
This photograph depicts Clostridium difficile colonies after 48hrs growth on a blood agar plate; Magnified 4.8X. C. difficile, an anaerobic gram-positive rod, is the most frequently identified cause of antibiotic-associated diarrhea (AAD). It accounts for approximately 15-25% of all episodes of AAD. Credit: CDCA new treatment for Clostridium difficile (C.diff) infections reduces recurrent infections by nearly 40%, a large study has found.
29 jan 2017--C.diff, a bacterium that infects the bowel, is the most common cause of infectious diarrhea in hospitalised patients. Recurrences are common after antibiotic treatment, are a cause of readmissions to hospital, and in some cases can be fatal.
Now a team of researchers have found that the addition of a drug called bezlotoxumab (Merck) to standard antibiotic treatment can reduce the risk of a repeat infection by 37%. Bezlotoxumab is a human monocalonal antibody and works by neutralising a toxin produced by the C.diff bacteria that damages the gut wall.
Mark Wilcox, Professor of Microbiology at the University of Leeds, led the study, which is published today in the New England Journal of Medicine.
Professor Wilcox said: "About one in four patients who have been treated with antibiotics for an initial C.diff infection will go on to have a repeat infection.
"These repeat infections are more difficult to treat, have more severe outcomes for the patient, and are associated with more hospitalisations. It is important to treat the first episodes of C. diff infection optimally, as each recurrence increases the chance of another episode even more.
"Fewer recurrent infections would mean less need to use antibiotics, fewer hospital admissions, reduced costs for the NHS and possibly a reduction in deaths."
For the study, doctors conducted a double-blind, randomised, placebo-controlled trial involving 2,655 adults across over 300 hospitals in 30 countries worldwide.
All the participants had primary or recurrent C.diff infections and were receiving standard-of-care antibiotics (metronidazole, vancomycin or fidaxomicin).
They were randomly assigned to receive infusions of:
- a single dose of (another human monocalonal antibody) actoxumab (10mg per kilogram of body weight)
- a single dose of bezlotoxumab (10mg per kilogram of body weight)
- a single dose of bezlotoxumab plus actotoxumab (10mg per kg of body weight)
- a placebo (saline)
After initial cure of their C.diff, the patients were then followed up for 12 weeks to see how many developed another C.diff infection.
- In the actoxumab group, 26% developed another C.diff infection
- In the bezlotoxumab group, 17% developed another C.diff infection
- In the bezlotoxumab/actotoxumab group, 15% developed another C.diff infection
- In the placebo group, 27% developed another C.diff infection.
"Doctors should now consider which patients could best benefit from use of bezlotoxumab," said Professor Wilcox.
"The studies showed that bezlotoxumab was particularly effective in those patients with risk factors for poor outcome, including older age, immunocompromise, and severe infection."
27 jan 2017—A physician-delivered step count prescription strategy with an individualized rate of increase can result in an increase in step count/day, according to a study published online Jan. 11 in Diabetes, Obesity and Metabolism.
Kaberi Dasgupta, M.D., from the McGill University Health Centre in Montreal, and colleagues examined the effects of physician-delivered step count prescriptions and monitoring. Participants were randomized to a control arm or an active arm, in which they were provided with pedometers and recorded step counts. Physicians reviewed their records over a one-year period and provided a written step count prescription with a goal of a 3,000-step/day increase (individualized rate of increase). Participants in the control arm were advised to engage in 30 to 60 minutes of physical activity per day. Seventy-nine percent of the 347 participants completed the final evaluation.
The researchers found that there was a net increase of 20 percent in steps/day for active versus control participants (1,190 steps). Inconclusive changes were seen in carotid femoral pulse wave velocity. Among participants with type 2 diabetes, active versus control participants experienced a lowering of hemoglobin A1c (−0.38 percent). The active versus control arm also showed a decrease in homeostasis model assessment-insulin resistance (−0.96 in all participants not treated with insulin).
"A simple physician-delivered step count prescription strategy incorporated into routine clinical practice led to a net 20 percent increase in step counts, though below the 3,000 steps/day targeted increment," the authors write.
Age modifies impact of resting heart rate on death, CV events
26 jan 2017—The effect of resting heart rate (RHR) on all-cause mortality and cardiovascular events varies with age, according to a study published online Dec. 30 in the Journal of the American Geriatrics Society.
Kuibao Li, M.D., from Capital Medical University in Beijing, and colleagues conducted a prospective cohort study involving 6,209 individuals aged 40 years and older without cardiovascular disease at baseline. Participants were interviewed in 1991 using a standard questionnaire to obtain information on demographics, medical history, and lifestyle risk factors. RHR was categorized according to quartiles.
The researchers found that 840 subjects died and 676 experienced a cardiovascular event during a mean follow-up of 8.3 years. In older participants (≥60 years), there was a significant association for higher RHR with all-cause mortality (P trend < 0.001) and cardiovascular events (P trend = 0.002), which was not seen in younger participants (<60 both="" p="" trend="" years=""> 0.05). Age had a significant modifying effect on the correlation between RHR and all-cause mortality and cardiovascular events (P interaction < 0.001 and P interaction = 0.002, respectively). After exclusion of individuals who died or had a cardiovascular event during the first two years of follow-up the results were similar.
"High RHR appears to be an independent determinant of all-cause mortality and cardiovascular events in older but not younger individuals," the authors write.
Meditation and music may help reverse early memory loss in adults at risk for Alzheimer's disease
In a recent study of adults with early memory loss, a West Virginia University research team lead by Dr. Kim Innes found that practice of a simple meditation or music listening program may have multiple benefits for older adults with preclinical memory loss.
25 jan 2017--In this randomized controlled trial, 60 older adults with subjective cognitive decline (SCD), a condition that may represent a preclinical stage of Alzheimer's disease, were assigned to either a beginner meditation (Kirtan Kriya) or music listening program and asked to practice 12 minutes/day for 12 weeks. As detailed in a paper recently published by the Journal of Alzheimer's Disease, both the meditation and music groups showed marked and significant improvements in subjective memory function and objective cognitive performance at 3 months. These included domains of cognitive functioning most likely to be affected in preclinical and early stages of dementia (e.g., attention, executive function, processing speed, and subjective memory function). The substantial gains observed in memory and cognition were maintained or further increased at 6 months (3 months post-intervention).
As explained in the research team's previous paper (J Alzheimer's Dis. 52 (4): 1277-1298), both intervention groups also showed improvements in sleep, mood, stress, well-being and quality of life, with gains that were that were particularly pronounced in the meditation group; again, all benefits were sustained or further enhanced at 3 months post-intervention.
The findings of this trial suggest that two simple mind-body practices, Kirtan Kriya meditation and music listening, may not only improve mood, sleep, and quality of life, but also boost cognition and help reverse perceived memory loss in older adults with SCD.
More information: Kim E. Innes et al. Meditation and Music Improve Memory and Cognitive Function in Adults with Subjective Cognitive Decline: A Pilot Randomized Controlled Trial, Journal of Alzheimer's Disease (2017). DOI: 10.3233/JAD-160867
Provided by IOS Press
Saturday, January 21, 2017
Senescence promotes chemotherapy side effects and cancer relapse
Credit: Buck InstituteStandard chemotherapy is a blunt force instrument against cancer – and it's a rare cancer patient who escapes debilitating side effects from systemic treatments that mostly affect dividing cells, both malignant and healthy, throughout the body.
21 jan 2017--Researchers at the Buck Institute and elsewhere now show that chemotherapy triggers a pro-inflammatory stress response termed cellular senescence, promoting the adverse effects of chemotherapy as well as cancer relapse and metastasis. Eliminating the senescent cells in mice prevented the side effects and relapse. The research is published in Cancer Discovery.
"While chemotherapy does save lives, it often comes with a very high price," said Judith Campisi, PhD, Buck faculty and senior scientist on the study. "Our work in mice studied the effects of chemotherapy on cancer relapse and other serious side effects. It provides a proof-of-principle that we hope can be translated into clinical practice."
Campisi's latest work highlights the two-faced nature of cellular senescence. It's a biological mechanism that puts a break on cancer by permanently stopping stressed cells from dividing, but it also contributes to aging and late-life cancers. That's because senescent cells are not benign – they secrete inflammatory molecules that damage neighboring tissues and cells. "Chemotherapy induces widespread senescence, contributing to persistent local and systemic inflammation," Campisi said. "That's why many patients feel so awful following treatment."
The research, led by Marco Demaria, PhD, a former postdoc in the Campisi lab, utilized transgenic mice that permit tracking and eliminating senescent cells. Results showed that eliminating chemotherapy-induced senescent cells reduced several short-and long-term effects of treatment, including bone marrow suppression, toxicity to the heart, cancer recurrence and metastasis, and physical activity and strength. Common chemotherapy drugs Doxorubicin, Paclitaxel, Temozolomide and Cisplatin were used to treat the mice.
Demaria, who is now a principle investigator at the European Research Institute for the Biology of Ageing, at the University Medical Center, Groningen, Netherlands, said some of the most striking results involved running speed – an indicator of fatigue in mice. "Eliminating senescent cells was sufficient to almost entirely rescue the decline in physical activity in the treated mice," he said. "Normally, mice spend 40 percent of their time running. After chemotherapy that activity dropped to 10 percent. When we knocked out the senescent cells the mice returned to normal running."
"Fatigue, which can be long-lasting, is a big deal for patients on chemotherapy," said Norman E. Sharpless, MD, Director of the Lineberger Comprehensive Cancer Center at the University of North Carolina in Chapel Hill and a co-author of the study, "Years later they often say that was the worst part of the treatment.
"Chemotherapy-induced bone marrow injury can lead to reduction in blood cell production, which can contribute to chemotherapy-induced fatigue," Said Daohong Zhou, MD, Associate Director for Basic Research of the Winthrop P. Rockefeller Cancer Institute at the University of Arkansas for Medical Sciences in Little Rock and a co-author of the study, "Eliminating senescent cells can promote bone marrow recovery after chemotherapy."
Sharpless looked at blood markers of cellular senescence in 89 women with breast cancer before they underwent chemotherapy aimed at curing their disease. "Women who went into chemotherapy with the highest existing burden of senescent cells experienced the most debilitating fatigue after treatment," he said. "It didn't really matter what particular drug was used – the results following chemotherapy tracked to the existing burden of senescent cells."
"We are excited about the potential applications of this work," said Campisi. "It would be a huge benefit if we could reduce the risk of cancer relapse and metastasis in patients. We also think it would be great to mitigate the other side effects of chemotherapy, the fear of which sometimes keep patients from seeking treatment."
More information: M. Demaria et al. Cellular Senescence Promotes Adverse Effects of Chemotherapy and Cancer Relapse, Cancer Discovery (2016). DOI: 10.1158/2159-8290.CD-16-0241
Provided by Buck Institute
Tuesday, January 17, 2017
ACP and AAFP release guideline for treatment of hypertension in older adults
The American College of Physicians (ACP) and the American Academy of Family Physicians (AAFP) have published an evidence-based clinical practice guideline on the appropriate systolic blood pressure target for adults 60 years old and older with hypertension. The joint guideline is published in today's issue of Annals of Internal Medicine and a summary of the guideline will be published in the March/April 2017 issue of the Annals of Family Medicine.
17 jan 2017--Hypertension, an elevation of systemic arterial blood pressure, is one of the most common chronic diseases in the United States. About 65 percent of adults in the U.S. over the age of 60 have hypertension, and the disease affects about 29 percent of all adults in the nation.
ACP and AAFP are two of the largest physician organizations in the U.S. representing primary care doctors. Their combined 272,900 members, including internal medicine physicians (internists) and family physicians, treat the majority of patients in the U.S. with hypertension.
ACP and AAFP recommend that physicians initiate treatment in adults aged 60 years old and older with persistent systolic blood pressure at or above 150 millimeters of mercury (mm Hg) to achieve a target systolic blood pressure of less than 150 mm Hg to reduce the risk of mortality, stroke, and cardiac events.
"The evidence showed that any additional benefit from aggressive blood pressure control is small, with a lower magnitude of benefit and inconsistent results across outcomes," said Nitin S. Damle, MD, MS, MACP, president. ACP. "Most benefits of targeting of less than 150 mm Hg apply to individuals regardless of whether or not they have diabetes."
The guideline notes that some patients may have falsely elevated readings in clinical settings ("white coat hypertension"). Therefore, it is important for physicians to ensure that they are accurately measuring blood pressure before initiating or changing treatment for hypertension.
"The most accurate measurements come from multiple blood pressure measurements made over time," said John Meigs, Jr., MD, president, AAFP "These may include multiple measurements in clinical settings or ambulatory or home-monitoring."
The guideline includes two additional recommendations:
- ACP and AAFP recommend that physicians consider initiating or intensifying drug therapy in adults aged 60 years old and older with a history of stroke or transient ischemic attack to achieve a target systolic blood pressure of less than 140 mm Hg to reduce the risk of recurrent stroke.
- ACP and AAFP recommend that physicians consider initiating or intensifying pharmacological treatment in some adults aged 60 years old and older at high cardiovascular risk, based on individualized assessment, to achieve a target systolic blood pressure of less than 140 mm Hg to reduce the risk of stroke or cardiac events.
Increased cardiovascular risk includes all people with known vascular disease and among others, is defined as most patients with diabetes, individuals with chronic kidney disease with estimated glomerular filtration rate (eGFR) <45 1.73="" abdominal="" age.="" and="" diabetes="" dyslipidemia="" hypertension="" m2="" metabolic="" min="" ml="" obesity="" older="" p="" per="" syndrome="">When prescribing drug therapy, physicians should select generic formulations over brand name drugs, which have similar efficacy, reduced cost, and therefore better adherence, ACP and AAFP advise.
Because of insufficient evidence, ACP and AAFP did not make any recommendations about diastolic blood pressure targets. Guideline Development Process
"Pharmacological Treatment of Hypertension in Adults Over Age 60 to Higher vs. Lower Targets" is based on a systematic review of published randomized controlled trials for primary outcomes and observational studies for harms only from database inception through January 2015, and updated with a MEDLINE search through September 2016. Evaluated outcomes included all-cause mortality, morbidity and mortality related to stroke, major cardiac events (fatal and nonfatal myocardial infarction and sudden cardiac death), and harms.
ACP's clinical practice guidelines are developed through a rigorous process based on an extensive review of the highest quality evidence available, including randomized control trials and data from observational studies. ACP also identifies gaps in evidence and direction for future research through its guidelines development process.
New urine test can quickly detect whether a person has a healthy diet
Scientists have developed a urine test that measures the health of a person's diet. The five-minute test measures biological markers in urine created by the breakdown of foods such as red meat, chicken, fish and fruit and vegetables. The analysis, developed by researchers from Imperial College London, Newcastle University and Aberystwyth University, also gives an indication of how much fat, sugar, fibre and protein a person has eaten.
13 jan 2017--Although the work is at an early stage, the team hope that with future development the test will be able to track patients' diets. It could even be used in weight loss programmes to monitor food intake.
Evidence suggests people inaccurately record their own diets, and under-report unhealthy food while over-reporting fruit and vegetable intake—and that the likelihood of inaccuracies in food diaries increases if a person is overweight or obese.
Professor Gary Frost, senior author of the study from the Department of Medicine at Imperial said: "A major weakness in all nutrition and diet studies is that we have no true measure of what people eat. We rely solely on people keeping logs of their daily diets—but studies suggest around 60 per cent of people misreport what they eat to some extent. This test could be the first independent indicator of the quality of a person's diet—and what they are really eating."
In study, published in the journal Lancet Diabetes and Endocrinology and conducted at the MRC-NIHR National Phenome Centre, the researchers asked 19 volunteers to follow four different diets, ranging from very healthy to very unhealthy (see notes to editors). These were formulated using World Health Organisation dietary guidelines, which advise on the best diets to prevent conditions such as obesity, diabetes and heart disease.
The volunteers strictly followed these diets for three days while in a London research facility, throughout which the scientists collected urine samples in the morning, afternoon and evening.
The research team then assessed the urine for hundreds of compounds, called metabolites, produced when certain foods are broken down in the body.
These included compounds that indicate red meat, chicken, fish, fruit and vegetables, as well as giving a picture of the amount of protein, fat, fibre and sugar eaten. They also included compounds that point to specific foods such as citrus fruits, grapes and green leafy vegetables.
From this information the researchers were able to develop a urine metabolite profile that indicated a healthy, balanced diet with a good intake of fruit and vegetables. The idea is this 'healthy diet' profile could be compared to the diet profile from an individual's urine, to provide an instant indicator of whether they are eating healthily.
The scientists then tested the accuracy of the test on data from a previous study. This included 225 UK volunteers as well as 66 people from Denmark. All of the volunteers had provided urine samples, and kept information on their daily diets.
Analysis of these urine samples enabled the researchers in the current study to accurately predict the diet of the 291 volunteers.
Professor John Mathers, co-author from the Human Nutrition Research Centre at Newcastle University, said: "For the first time, this research offers an objective way of assessing the overall healthiness of people's diets without all the hassles, biases and errors of recording what they've eaten."
The team now hope to refine the technology by testing it on larger numbers of people. They also need to further assess the accuracy of the test on an average person's diet, outside of a research setting.
Dr Isabel Garcia-Perez, co-author from the Faculty of Medicine at Imperial explained: "We need to develop the test further so we can monitor the diet based on a single urine sample, as well as increase the sensitivity. This will eventually provide a tool for personalised dietary monitoring to help maintain a healthy lifestyle. We're not at the stage yet where the test can tell us a person ate 15 chips yesterday and two sausages, but it's on the way."
The team added the technology may one day be used alongside weight loss programmes, as well as patient rehabilitation, for instance to help heart attack patients follow a healthy diet.
Professor Elaine Holmes, co-author from the Department of Surgery and Cancer at Imperial added: "We are hoping to make this test available to the public within the next two years. The idea would be to collect a urine sample at home and deliver it to a local centre for analysis. We envisage the tool being used by dieticians to help guide their patients' dietary needs, or even by individuals who are interested in finding out more about the relationship between diet and their health"
Dr Des Walsh, head of population and systems medicine at the Medical Research Council said: "Though this research is still in its early stages, it's grappling with essential methods in food and diet studies where advances are really needed. Measuring what we eat and drink more accurately will widen the benefits of nutrition research, developing better evidence-based interventions to improve individual's health and reduce obesity."
Professor John Draper, co-author from Aberystwyth University added: "The future challenge is to apply the technology developed in this laboratory study in a community setting and objectively monitor diet in the home. The teams in Aberystwyth and Newcastle have been doing just this and the results are looking very promising."
Provided by Imperial College London
Exercise... It does a body good: 20 minutes can act as anti-inflammatory
Credit: Peter Griffin/Public DomainIt's well known that regular physical activity has health benefits, including weight control, strengthening the heart, bones and muscles and reducing the risk of certain diseases.
13jan 2017--Recently, researchers at University of California San Diego School of Medicine found how just one session of moderate exercise can also act as an anti-inflammatory. The findings have encouraging implications for chronic diseases like arthritis, fibromyalgia and for more pervasive conditions, such as obesity.
The study, recently published online in Brain, Behavior and Immunity, found one 20-minute session of moderate exercise can stimulate the immune system, producing an anti-inflammatory cellular response.
"Each time we exercise, we are truly doing something good for our body on many levels, including at the immune cell level," said senior author Suzi Hong, PhD, in the Department of Psychiatry and the Department of Family Medicine and Public Health at UC San Diego School of Medicine. "The anti-inflammatory benefits of exercise have been known to researchers, but finding out how that process happens is the key to safely maximizing those benefits."
The brain and sympathetic nervous system—a pathway that serves to accelerate heart rate and raise blood pressure, among other things—are activated during exercise to enable the body to carry out work. Hormones, such as epinephrine and norepinephrine, are released into the blood stream and trigger adrenergic receptors, which immune cells possess.
This activation process during exercise produces immunological responses, which include the production of many cytokines, or proteins, one of which is TNF—a key regulator of local and systemic inflammation that also helps boost immune responses.
"Our study found one session of about 20 minutes of moderate treadmill exercise resulted in a five percent decrease in the number of stimulated immune cells producing TNF," said Hong. "Knowing what sets regulatory mechanisms of inflammatory proteins in motion may contribute to developing new therapies for the overwhelming number of individuals with chronic inflammatory conditions, including nearly 25 million Americans who suffer from autoimmune diseases."
The 47 study participants walked on a treadmill at an intensity level that was adjusted based on their fitness level. Blood was collected before and immediately after the 20 minute exercise challenge.
"Our study shows a workout session doesn't actually have to be intense to have anti-inflammatory effects. Twenty minutes to half-an-hour of moderate exercise, including fast walking, appears to be sufficient," said Hong. "Feeling like a workout needs to be at a peak exertion level for a long duration can intimidate those who suffer from chronic inflammatory diseases and could greatly benefit from physical activity."
Inflammation is a vital part of the body's immune response. It is the body's attempt to heal itself after an injury; defend itself against foreign invaders, such as viruses and bacteria; and repair damaged tissue. However, chronic inflammation can lead to serious health issues associated with diabetes, celiac disease, obesity and other conditions.
"Patients with chronic inflammatory diseases should always consult with their physician regarding the appropriate treatment plan, but knowing that exercise can act as an anti-inflammatory is an exciting step forward in possibilities," said Hong.
More information: Stoyan Dimitrov et al, Inflammation and exercise: Inhibition of monocytic intracellular TNF production by acute exercise via β2-adrenergic activation, Brain, Behavior, and Immunity (2016). DOI: 10.1016/j.bbi.2016.12.017
Provided by University of California - San Diego
Wednesday, January 11, 2017
Mediterranean diet may protect your brain in old age, new finding suggests
Amid the contention about diets and detoxes, sugar and fats, there is at least general agreement that a Mediterranean diet – fruit, vegetables, olive oil, grains, fish – is a good thing.
11 jan 2017--Now, a new study based on brain imaging in over 400 people seems to show that we have even more reason to celebrate this diet and, more importantly, to stick to it. The researchers found that over a three-year period – from the age of 73 to 76 – adherence to a Mediterranean diet is associated with a reduction in the inevitable loss of brain volume that occurs with age.
The difference in volume loss associated with the diet is not large – about 2.5ml (half a teaspoon) – and it only accounts for a very small fraction of overall volume variability. But, who's to say what you might achieve with that extra half teaspoon of brain? If these results prove reliable, there is surely an incentive to stock up on family-sized bottles of olive oil.
We already have evidence that the Mediterranean diet, and particularly higher fish and lower meat consumption, is associated with increased brain size. But it's hard to interpret associations between lifestyle and the brain because a causal relationship is equally credible in both directions. That is to say, if I eat healthily and have a big brain, it might be that my diet is good for my brain or my big brain is good at helping me maintain my diet. Or there may be something that I haven't measured, something that influences my brain and my diet separately. For example, if I live a comfortable, affluent, stress-free life perhaps this is simultaneously good for my brain and facilitates my healthy diet. If so, finding a healthy association between diet and a big brain does not mean that they are directly related.
These are critical considerations. Citing evidence to support lifestyle changes demands that one knows the precise lifestyle changes needed and what the precise benefits may be. This is why randomised control studies are so appealing. If you have two well-matched groups, subject them two controlled dietary interventions, and do a before and after analysis, you are on firmer ground when asserting that the dietary intervention has had a direct role in producing the changes.
While the researchers in this latest study did not carry out a randomised trial, however, they have nevertheless provided important insights by gathering repeat data, allowing them to compare brain size not in terms of absolute values but of changes across time.
At age 70, participants gave a detailed report on their dietary habits. On this basis, they could be characterised as "high" and "low" in their adherence to a Mediterranean diet. Three years later, they had a baseline brain scan and, a further three years afterwards, brain changes from this baseline were assessed with a second brain scan, so every participant served as their own control. This is a powerful approach and, as well as using the initial scans to confirm that brain volume is indeed greater in people who follow the Mediterranean diet more closely, they determined that, between the ages of 73 and 76 years, there was a greater loss of brain volume for those with low adherence to the diet. This remained significant when taking into account a number of highly relevant factors relating to age, sex, health, body weight, education and aspects of psychological functions.
The brain inevitably shrinks with age. Credit: gmstockstudio/Shutterstock.comInterpret with caution
These findings are consistent with the heartening possibility that the right diet has a genuine impact on brain tissue loss. But the authors are cautious, and rightly so. To begin with, their results are not entirely consistent with previous studies of the diet's effects on the brain. They failed to find, for example, previously-observed effects of higher fish and lower meat consumption. It becomes hard to know whether it is the diet as a whole or specific components of it that could exert the positive effect on brain volume.
The analysis also shows that cognitive function did not significantly differ across the diet styles, raising the question of just how useful it might be to alter brain loss at this scale.
Also, as the researchers acknowledge, they carried out several statistical tests looking for significant associations – ones that have a low p-value (the probablility of finding this difference when there is not a true difference in brain size) – and from this they found the reduction in brain loss. But if you take all of these searches into account, picking out a significant association (brain volume) from non-significant ones (for example, a lack of change to the volume of grey matter), you increase your chances of accidentally attributing significance to something that occurs just by chance.
Although the authors have made nice attempts in their design and analysis in ruling out potentially complicating factors, there is still necessarily an ambiguity over cause and effect here. They previously showed in another study that an apparent relationship between Mediterranean diet and later-life cognitive functions could actually be accounted for by childhood IQ.
While the current analysis ruled out a similar explanatory role of a more constrained IQ measure and of a set of tests of mental function, we must bear in mind the possibility that there are other factors, unaccounted for here, that could separately relate to dietary adherence and brain volume and would therefore produce an illusion of a dietary influence on brain. For example, it's not clear whether excessive alcohol consumption might associate with a non-Mediterranean diet. Or perhaps levels of physical activity could also play a part.
But, at the same time, there are reasons why this finding – that adherence to a Mediterranean diet results in less brain loss in the elderly – may be even stronger than the numbers show. Participants were split according to the general style of their diet. So some in the high and low diet groups would actually have been quite near the mid-point and so less likely to show strong effects. One might imagine that, if you took two groups who more purely exemplified the Mediterranean and non-Mediterranean diets, there could be even bigger effects on brain volume. We shall see. In any case, keep eating the legumes. Even if it turns out that the Mediterranean diet doesn't stop your brain from shrinking, there are still plenty of other benefits to be had.
Provided by University of Cambridge
Friday, January 06, 2017
Living close to major roads linked to small increase in dementia risk
A study of over 6.5 million Ontario residents raises public health concerns about the impact of air pollution and noise. Credit: Public Health Ontario and the Institute for Clinical Evaluative SciencesDementia is more common in people who live within 50 metres of a major road than those who live further away, according to a study looking at 6.6 million people published in The Lancet. However, the study found no link between traffic exposure and Parkinson's disease or multiple sclerosis.
06 jan 2017--The observational study estimated that up to one in 10 (7-11%) cases of dementia among those who live within 50 metres of a major road could be attributed to traffic exposure.
Previous research has suggested that air pollution and traffic noise may contribute to neurodegeneration, with one study finding that living near a road was associated with reduced white matter and lower cognition. However, the paper in The Lancet is the first to investigate the link between living close to heavy traffic and the onset of major neurodegenerative diseases.
The researchers tracked all adults aged between 20 and 85 living in Ontario, Canada - approximately 6.6 million people - for over a decade from 2001 to 2012. They used postcodes to determine how close people lived to a road and analysed medical records to see if they went on to develop dementia, Parkinson's disease or multiple sclerosis.
Almost all people (95%) in the study lived within one kilometre of a major road and half lived within 200 metres of one. Over the study period, more than 243000 people developed dementia, 31500 people developed Parkinson's disease and 9250 people developed multiple sclerosis.
While there was no association between living near a road and Parkinson's disease or multiple sclerosis, dementia was more common the closer people lived to busy roads. The risk of developing dementia reduced as people lived further away from a main road - with a 7% higher risk in developing dementia among those living within 50 metres, a 4% higher risk at 50-100 metres, a 2% higher risk at 101-200 metres and no increase in risk in those living more than 200 metres away.
The researchers also found that long-term exposure to two common pollutants (nitrogen dioxide and fine particulate matter) was associated with dementia but this did not account for the full effect, meaning other factors are also likely to be involved. These could include other air pollutants or noise from traffic.
"Despite the growing impact of these diseases, little is known about their causes and prevention," said lead author Dr Hong Chen, Public Health Ontario, Canada. "Our study suggests that busy roads could be a source of environmental stressors that could give rise to the onset of dementia. Increasing population growth and urbanisation has placed many people close to heavy traffic, and with widespread exposure to traffic and growing rates of dementia, even a modest effect from near-road exposure could pose a large public health burden. More research to understand this link is needed, particularly into the effects of different aspects of traffic, such as air pollutants and noise."
The study estimated air pollution exposure based on postcode, so does not account for each individual's exposure. Because the study is observational it cannot establish causality, but the study was designed to control for socioeconomic status, education levels, BMI and smoking meaning the link is unlikely to be explained by these factors.
Writing in a linked Comment, Dr Lilian Calderón-Garcidueñas, University of Montana, USA, said: "The significant association of newly diagnosed cases of dementia in the study period between 2001 and 2012 with the proximity to traffic road less than 50 m-300 m versus more than 300 m, and the robust observation of dementia involving predominantly urban versus rural residents, opens up a crucial global health concern for millions of people... The health repercussions of living close to heavy traffic vary considerably among exposed populations, given that traffic includes exposures to complex mixtures of environmental insults... We must implement preventive measures now, rather than take reactive actions decades from now."
Sugar-free and 'diet' drinks no better for healthy weight than full sugar drinks, experts say
Credit: CC0 Public DomainSugar-free and "diet" drinks are often seen as the healthier option - but researchers from Imperial College London have argued that they are no more helpful for maintaining a healthy weight than their full-sugar versions.
05 jan2017--In a commentary on current research and policy into sweetened drinks, academics from Imperial College London and two Brazilian universities (University of Sao Paulo and Federal University of Pelotas) argued that sugar-free versions of drinks may be no better for weight loss or preventing weight gain than their full sugar counterparts, and may also be detrimental to the environment.
Artificially-sweetened beverages (ASBs) are alternatives to full-sugared drinks. They contain no sugar and are sweetened with artificial sweeteners instead. ASBs are often known as "diet" versions of soft drinks, and may be perceived by consumers as the healthier option for those who want to lose weight or reduce their sugar intake. However, there is no solid evidence to support the claims that they are any better for health or prevent obesity and obesity related diseases such as type 2 diabetes.
Professor Christopher Millett, senior investigator from Imperial's School of Public Health, said "A common perception, which may be influenced by industry marketing, is that because 'diet' drinks have no sugar, they must be healthier and aid weight loss when used as a substitute for full sugar versions. However we found no solid evidence to support this."
Sugar-sweetened beverages (SSBs) such as soft drinks, fruit-flavoured drinks, and sports drinks, make up a third of UK teenagers' sugar intake, and nearly half of all sugar intake in the US. SSBs provide many calories but very few essential nutrients, and their consumption is a major cause of increasing rates of obesity and type 2 diabetes.
ASBs currently comprise a quarter of the global sweetened beverages market, but they are not taxed or regulated to the same extent as SSBs - perhaps due to their perceived harmlessness, say the researchers.
Despite having no or very little energy content, there is a concern that ASBs might trigger compensatory food intake by stimulating sweet taste receptors. This, together with the consumers' awareness of the low-calorie content of ASBs, may result in overconsumption of other foods, thus contributing to obesity, type 2 diabetes and other obesity-related health problems.
Professor Millett and colleagues outlined current evidence of the health effects of consuming ASBs. Although there was no direct evidence for a role of ASBs in weight gain, they found that there was no evidence that ASBs aid weight loss or prevent weight gain compared with the full sugar versions.
In addition, the production of ASBs has negative consequences for the environment, with up to 300 litres of water required to produce a 0.5 L plastic bottle of carbonated soft drink.
Dr Maria Carolina Borges, first author of the study from the Federal University of Pelotas in Brazil added: "The lack of solid evidence on the health effects of ASBs and the potential influence of bias from industry funded studies should be taken seriously when discussing whether ASBs are adequate alternatives to SSBs."
Professor Carlos Monteiro, co-author from the University of Sao Paulo, said: "Taxes and regulation on SBS and not ASBs will ultimately promote the consumption of diet drinks rather than plain water - the desirable source of hydration for everyone."
The authors added: "Far from helping to solve the global obesity crisis, ASBs may be contributing to the problem and should not be promoted as part of a healthy diet."
More information: "Artificially Sweetened Beverages and the Response to the Global Obesity Crisis" Maria Carolina Borges, Maria Laura Louzada, Thiago Herick de Sa , Anthony A. Laverty, Diana C. Parra, Josefa Maria Fellegger Garzillo, Carlos Augusto Monteiro, Christopher Millett, PLOS Medicine, 2017.
Provided by Imperial College London
Tuesday, January 03, 2017
New study finds EPA and DHA omega-3s lower risk of coronary heart disease
EPA and DHA omega-3s reduce the risk of coronary heart disease (CHD), according to results of a new, comprehensive meta-analysis published in the Mayo Clinic Proceedings.
03 jan 2017--Among randomized controlled trials (RCTs), there was a statistically significant reduction in CHD risk in higher risk populations, including:
16 percent in those with high triglycerides and 14 percent in those with high LDL cholesterol.
A non-statistically significant 6 percent risk reduction among all populations in RCTs, a finding supported by a statistically significant 18 percent reduced risk of CHD among prospective cohort studies.
"What makes this paper unique is that it looked at the effects of EPA and DHA on coronary heart disease specifically, which is an important nuance considering coronary heart disease accounts for half of all cardiovascular deaths in the U.S.," said Dr. Dominik Alexander, lead author and Principal Epidemiologist for EpidStat. "The 6 percent reduced risk among RCTs, coupled with an 18 percent risk reduction in prospective cohort studies—which tend to include more real-life dietary scenarios over longer periods—tell a compelling story about the importance of EPA and DHA omega-3s for cardiovascular health."
Additional study details include:
The study reviewed 18 randomized controlled trials (RCTs) and 16 prospective cohort studies, with 93,000 and 732,000 subjects, respectively.
The study examined outcomes such as myocardial infarction, sudden cardiac death and coronary death.
The study compared the results of RCTs, which explore interventions under strict clinical conditions, to those of prospective cohort studies that are observational, and followed larger populations for longer periods of time.
"There are important public health implications related to reducing the risk of coronary heart disease, and therefore we are encouraged by the results of this comprehensive analysis," said Dr. Harry Rice, Vice President of Regulatory and Scientific Affairs for the Global Organization for EPA and DHA Omega-3s (GOED), which funded the study. "It's also important that the observed risk reductions were even stronger in patient populations with elevated triglycerides and LDL cholesterol levels, two risk factors that affect more than one quarter of the American population."
"The results confirm that increasing omega-3s is a healthy lifestyle intervention that can contribute towards reductions in CHD risk," added Adam Ismail, Executive Director of GOED. "Remember that increasing omega-3 intakes is basically just improving the quality of one's diet slightly, like reducing the amount of sodium or increasing your dietary fiber. It is a simple, inexpensive, and achievable change that most consumers need to make to optimize their health."
An accompanying editorial in Mayo Clinic Proceedings also acknowledges the importance of the study. "The meta-analyses of Alexander and colleagues suggests that omega-3 fatty acid intake may reduce risk of adverse CHD events, especially among people with elevated levels of TGs or LDL-C....omega-3 fatty acid intake of at least 1 gram of EPA+DHA per day, either from seafood or supplementation (as recommended by the American Heart Association), continues to be a reasonable strategy," said the authors.
Study authors did point out that further clinical trials looking specifically at CHD outcomes may continue to provide a better understanding of the promising beneficial relationship between EPA/DHA and CHD risk. Current RCTs have varying durations, different baseline CHD status for study participants, and utilize several methods for patient selection and randomization. Future studies should:
Increase patient populations to account for dropout rates in longer trials.
Extensively detail how subjects are diagnosed to create uniform diagnostic criteria.
Be appropriately powered to detect an effect in current clinical conditions.
Measure baseline omega-3 intake or status of study participants to determine the extent to which it confounds results.
More information:Mayo Clinic Proceedings, DOI: 10.1016/j.mayocp.2016.10.018 The study was supported by a grant from GOED, which played no role in study design; in the collection, analysis, and interpretation of data; in the writing of the report; or in the decision to submit the article for publication.
Provided by GOED
Monday, January 02, 2017
Gut microorganisms affect our physiology
Credit: CC0 Public DomainResearchers have found evidence that could shed new light on the complex community of trillions of microorganisms living in all our guts, and how they interact with our bodies.
