Scientists Say You Should Do This Exercise at Least Twice a Week to Make Your Brain Work Better.


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Engaging in regular weightlifting could actually make your brain work better and prevent dementia, concludes new research by Australian scientists. As about 135 million people are estimated to develop dementia by 2050, the study’s findings are key in ensuring healthier brain function in the population.

The researchers focused on 100 people aged 55 to 86 with “mild cognitive impairment” (MCI) who were asked to do weight lifting and brain training. MCI is considered a precursor to developing Alzheimer’s disease and other forms of dementia.

In 2014, the same team published a paper outlining how cognition skills improve as a result of weight training. The benefits lasted even 12 months after that study concluded.

“What we found in this follow-up study is that the improvement in cognition function was related to their muscle strength gains. The stronger people became, the greater the benefit for their brain,” said the study’s lead author, Dr. Yorgi Mavros, of Sydney University.

Twice a week, over a six month period, the study’s participants worked with weights that were 80% as heavy as the max they could lift. The stronger they got, the more weight they lifted, sticking to the 80% rule.

Subsequent MRI scans of the study’s subjects showed an increase in certain areas of their brains.

While future studies will determine whether this holds true for people of any age group, the positive results encouraged Dr. Mavros to state a general recommendation for all.

“The more we can get people doing resistance training like weight lifting, the more likely we are to have a healthier ageing population,” said Dr. Mavros. “The key however is to make sure you are doing it frequently, at least twice a week, and at a high intensity so that you are maximising your strength gains. This will give you the maximum benefit for your brain.”

To build on their findings, the researchers are planning further studies.

“The next step now is to determine if the increases in muscle strength are also related to increases in brain size that we saw,” said the study’s senior author Professor Maria Fiatarone Singh, geriatrician at University of Sydney. “In addition, we want to find the underlying messenger that links muscle strength, brain growth, and cognitive performance, and determine the optimal way to prescribe exercise to maximise these effects.”

The Study of Mental and Resistance Training (SMART) trial was conducted by University of Sydney researchers in collaboration with the Centre for Healthy Brain Ageing (CHeBA) at University of New South Wales and the University of Adelaide.

Source: Journal of American Geriatrics Society.

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Blueberries May Boost Memory in Mild Cognitive Impairment


Eating blueberries may improve thinking and memory skills in older adults with mild cognitive impairment (MCI), new research suggests.

“There is a very large, basic-science literature ― molecular studies, cellular studies, and animal studies ― that demonstrates cognitive enhancement with blueberries, but there are only just a few human studies to date,” said lead researcher Robert Krikorian, PhD, University of Cincinnati Academic Health Center, in Ohio.

He presented results of two human blueberry studies March 13 at the 251st National Meeting and Exposition of the American Chemical Society (ACS), in San Diego, California.

Memory, Well-being Boost

In one study, 47 adults aged 68 years and older with MCI were randomly allocated to consume a freeze-dried blueberry powder equivalent to a cup of blueberries or a placebo powder once a day for 16 weeks. The researchers carried out pre- and postintervention cognitive tests on all participants and brain imaging in a subset.

“There was improvement in cognitive performance and brain function in those who had the blueberry powder compared with those who took the placebo,” Dr Krikorian reported.

The cognitive tests included a verbal list–learning task, a simple paper-and-pencil line drawing motor task, a visual-spatial memory task that involved nonverbal information, and a semantic access task. In the blueberry group, there was a significant 72% improvement in semantic access and a 13% improvement in visual-spatial memory, Dr Krikorian told Medscape Medical News. “And we had marginal effects for the other tests ― that is, trends that were close to significant but didn’t reach significance.

“In addition, we found that the blueberry-supplemented subjects showed increased activation in certain regions of the left hemisphere of the brain, and that did not occur with placebo-powder subjects,” he said.

The other study included 94 adults aged 62 to 80 years who had complaints concerning subjective memory. They were randomly allocated to receive the blueberry powder, fish oil, fish oil plus the blueberry powder, or placebo for 24 weeks.
“This study was of similar design but involved a larger population of older adults with normal cognitive function, and the supplementation period was 24 weeks as opposed to 16. The findings weren’t as robust in this study,” Dr Krikorian said, perhaps because these patients had less severe cognitive problems when they entered the study.

“The other interesting result was that the blueberry-supplemented participants felt they were performing better in their everyday lives. They had a better sense of well-being and were making fewer memory mistakes and were less inefficient than they had been relative to those that received the placebo powder,” he noted.

The beneficial effects of blueberries could be due to the presence of anthocyanins, flavonoids shown to improve cognition in animals, Dr Krikorian said.

“It’s important to do this work and for other programs as well to replicate what we are finding,” he noted. “And we need to know much more about the mechanisms of action and the proper dose and intervention period. There are a host of questions that have to be answered with human research.”

Interpret With Caution

These findings are “intriguing but should be interpreted with caution,” Keith N. Fargo, PhD, director of scientific programs and outreach, Alzheimer’s Association, noted in an interview with Medscape Medical News.

“I think the thing for people to remember here is that it is a small study, so there may be something here, [or] there may not be something here. Other people have looked at blueberries and found some protective effect, so it’s not outside the realm of possibilities, and if it’s true, it could be exciting,” Dr Fargo said.

“As a population, we are aging, and it’s going to be important for all of us to try to eat as healthy as we can,” he added. “It’s probably not about a single dietary change. It’s probably about making sure you are physically active and keeping your body weight in check and making sure you are eating a reasonable diet. Those things are going to be helpful for your cardiovascular health, and things that are helpful for your cardiovascular health are also helpful for your cognitive function as you age,” he added.

NASAL SPRAY WITH INSULIN EQUIVALENT SHOWS PROMISE AS TREATMENT FOR ADULTS WITH MILD COGNITIVE IMPAIRMENT, ALZHEIMER’S DEMENTIA


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A man-made form of insulin delivered by nasal spray may improve working memory and other mental capabilities in adults with mild cognitive impairment and Alzheimer’s disease dementia, according to a pilot study led by researchers at Wake Forest Baptist Medical Center.

The study’s subjects were 60 adults diagnosed with amnesic mild cognitive impairment (MCI) or mild to moderate Alzheimer’s dementia (AD). Those who received nasally-administered 40 international unit (IU) doses of insulin detemir, a manufactured form of the hormone, for 21 days showed significant improvement in their short-term ability to retain and process verbal and visual information compared with those who received 20 IU does or a placebo.

Additionally, the recipients of 40 IU doses carrying the APOE-e4 gene – which is known to increase the risk for Alzheimer’s – recorded significantly higher memory scores than those who received the loser dosage or placebo, while non-carriers across all three groups posted significantly lower scores.

Previous trials had shown promising effects of nasally-administered insulin for adults with AD and MCI, but this study was the first to use insulin detemir, whose effects are longer-lasting than those of “regular” insulin.

“The study provides preliminary evidence that insulin detemir can provide effective treatment for people diagnosed with mild cognitive impairment and Alzheimer’s-related dementia similar to our previous work with regular insulin,” said Suzanne Craft, Ph.D., professor of gerontology and geriatric medicine at Wake Forest Baptist and lead author of the study, which is published online in advance of the February issue of the Journal of Alzheimer’s Disease. “We are also especially encouraged that we were able to improve memory for adults with MCI who have the APOE-e4 gene, as these patients are notoriously resistant to other therapies and interventions.”

The researchers also sought to determine if the insulin detemir doses would cause any negative side effects, and found only minor adverse reactions among the subjects.

The study’s overall results support further investigation of the therapeutic value of insulin detemir as a treatment for Alzheimer’s and other neurodegenerative diseases, Craft said.

“Alzheimer’s is a devastating illness, for which even small therapeutic gains have the potential to improve quality of life and significantly reduce the overall burden for patients, families and society,” she said. “Future studies are warranted to examine the safety and efficacy of this promising treatment.”

Benefits of Dementia Screening Still Unclear.


Dementia screening instruments, such as the Mini-Mental State Examination (MMSE), can adequately pick up cognitive impairment in the primary care setting, but many of these tools have not been extensively studied, and there’s no empirical evidence that using them improves decision-making or important outcomes, according to a new literature review.

The review authors also suggest that despite decades of research, it’s still unclear whether cognitive or exercise interventions have a clinically significant effect.

The review was published online October 21 in the Annals of Internal Medicine.

No Basis for Routine Screening

Primary care clinicians may fail to recognize cognitive impairment using routine history and physical examination, according to the study authors. Most patients aren’t diagnosed until at least the moderate stage of the disease, they note.

In 2003, the US Preventive Services Task Force (USPSTF) concluded that there was insufficient evidence to recommend for or against routine screening for dementia in older adults. The current review was conducted in an effort to update these recommendations.

The review included 5 key questions:

1.     Does screening for cognitive impairment in community-dwelling older adults in primary care settings improve decision making or patient, family, caregiver or societal outcomes?

2.     What is the test performance of screening instruments to detect cognitive impairment in these elderly patients?

3.     What are the harms of screening?

4.     Do interventions for mild cognitive impairment (MCI) or mild to moderate dementia improve decision-making or outcomes?

5.     What are the harms of interventions for cognitive impairment?

An extensive review of the literature turned up no studies to answer the first question and only 1 study that addressed the third question. The review therefore concentrated on questions 2 (with 55 fair- to good-quality studies), 4 (131 studies), and 5 (66 studies).

Although the new review included twice the number of studies than existing reviews, its findings were generally consistent with previous findings.

Only 12 brief instruments have been assessed more than once in well-designed studies evaluating their ability to detect dementia in primary care–relevant populations. Only 4 studies were of good quality, with the rest having fair quality and various risks of bias.

In this analysis, the MMSE was the best-studied instrument, with pooled estimates across 14 studies resulting in a sensitivity of 88.3% and a specificity of 86.2% for the most commonly reported cut points. But the MMSE has the longest administration time and is not available for public use without cost, said the authors.

The Clock Drawing Test, Mini-Cog, Memory Impairment Screen, Abbreviated Mental Test, Short Portable Mental Status Questionnaire, Free and Cued Selective Reminding Test, 7-Minute Screen, and Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE) are available for public use in primary care settings but have been studied only in English.

Most of these instruments can have an acceptable test performance, but not much evidence supported their use, with reproducibility in primary care populations limited and optimum cut-points unknown, according to the authors.

Only 6 instruments were used in more than 1 study assessing diagnostic accuracy to detect MCI in primary care populations. Overall, the sensitivity for detecting MCI for each of these instruments, except for the IQCODE, was lower than that for detecting dementia.

Screening Harmful?

The reviewers identified 1 systematic review and 118 trials that addressed the benefits of the treatment or management of mild to moderate dementia, MCI, or both. Most trials (90%) were of fair quality. Medication trials were exclusively or partially industry funded.

The review included a well-conducted systematic review of US Food and Drug Administration–approved medications for the treatment of Alzheimer’s disease that included 39 randomized controlled trials of acetylcholinesterase inhibitors (AchEIs), as well as 9 additional randomized controlled trials.

Overall, on the basis of these fair- to good-quality trials, AchEIs can improve cognitive function and global functioning in the short term, but the pooled magnitude of these changes is small, with a change of about 1 to 3 points on the Alzheimer`s Disease Assessment Scale-Cognitive Subscale (ADAS-cog).

“The average effect of these changes may not be clinically meaningful as defined using commonly accepted values,” the authors write.

It’s still unclear whether AchEIs can improve physical functioning “given the inconsistent and sparsely reported findings,” they add.

On the basis of 10 fair- to good-quality trials of memantine, a drug approved for moderate to severe AD that has also been evaluated in patients with mild to moderate dementia or MCI, this agent had a benefit similar to that seen with AchEIs on global cognitive functioning in patients with moderate dementia.

These small average effects of change in cognitive function with AchEIs and memantine must be balanced by common adverse effects associated with them, the authors note.

None of the trials of other medications or dietary supplements, including low-dose aspirin, nonsteroidal anti-inflammatory drugs, and vitamins, found a benefit on cognitive or physical function in people with mild to moderate dementia or MCI.

The review found no studies to substantiate or refute concerns about harms of screening. However, the authors said that the harms of screening are poorly studied.

“Some have argued that these harms are minimal, whereas others have argued that the harms of screening and mislabeling persons with dementia are real given the variation in practice of diagnostic confirmation of disease. If broader adoption of screening for cognitive impairment is implemented, it would be wise to better understand these tradeoffs.”

Caregiver Burden

Overall, in trials of interventions targeting caregivers, there was generally a consistent finding of small benefit on caregiver burden and caregiver depression outcomes.

Pooled analyses of 24 trials showed a small but statistically significant effect (standardized mean difference, –0.23 [95% confidence interval (CI)], –0.35 to –0.12l) on caregiver burden. And pooled analyses of 30 trials showed a small but statistically significant effect (standardized mean difference of 0.21 [95% CI, –0.30 to –0.13]) on caregiver depression.

“The clinical meaning of these changes in caregiver burden and depression are, on average, probably small at best,” the authors write.

As well, the authors pointed out that many of the studies of complex interventions for caregivers were conducted outside the United States and may not be freely available.

There was limited reporting of findings for outcomes such as global stress or distress, anxiety, and health-related quality of life for caregivers.

Although evidence is limited and findings inconsistent, cognitive stimulation with or without cognitive training seemed to improve global cognitive function at 6 to 12 months for patients with MCI or dementia. However, the authors add, “the certainty and magnitude of effect of cognitive stimulation is still unclear.”

Exercise interventions also have limited evidence to support their use in patients with MCI or mild or moderate dementia. However, 3 of the better-conducted trials did suggest a benefit of exercise in global cognitive function or physical functioning and health-related quality of life.

The review did not address several important aspects of screening test performance, including the psychometric properties of testing other than sensitivity and specificity.

According to expert consensus guidelines, early detection of cognitive decline may lead to optimal medical management and ultimately lead to improved patient outcomes and reduced costs, but there is little or no empirical evidence to support this, the authors concluded.

“How and whether clinician decision-making and patient and family decision-making are affected by earlier identification of cognitive impairment or earlier management of patients with dementia and their caregivers are important aspects to understand in order to better manage this rapidly growing health care problem,” they write.

Research comparing which criteria — for example, age, comorbid conditions, or functional status — should lead primary care clinicians to perform cognitive assessment is much needed, the authors add. Additional evaluation of brief instruments in more representative populations is also needed.

Right Decision

Commenting on the review for Medscape Medical News was Malaz Boustani, MD, chief operating officer, Indiana University Center for Innovation and Implementation Science and chief innovation and implementation officer, Indiana University Health, Indianapolis.

Dr. Boustani’s research team, with support from the National Institute on Aging, is conducting the first randomized controlled trial to evaluate the benefit and harm of dementia screening in primary care. The trial has now enrolled more than 500 patients (of an eventual target of 4000) and final results are expected in 2017.

According to Dr. Boustani, the USPSTF decision not to recommend routine screening for dementia in primary care was the right one.

“The required data to make such an important and vital decision is not there yet,” he said.

J. Riley McCarten, MD, associate professor, Department of Neurology, University of Minnesota Medical School, medical director, Geriatric Research, Education and Clinical Center (GRECC), and medical director, The Memory Clinic, University of Minnesota Medical Center, Minneapolis, believes that the time for screening has arrived.

“We have the tools to identify dementia and to intervene” in what is a costly and rapidly growing major health care problem, said Dr. McCarten. “To successfully address this tragedy, we must first make diagnosing it a priority.”

Dr. McCarten took issue with the study authors’ conclusion that although screening can identify people with dementia, no empirical evidence exists to determine whether interventions affect decision-making. “Pretending that knowing whether someone has dementia has no effect on decision-making is illogical—and dangerous,” he said.

It’s impossible to “uncouple” identifying dementia—in this case, through screening—from decision-making about dementia, said Dr. McCarten. “Once dementia is identified, decisions are made based on that knowledge.”

Screening identifies patients for whom an intervention is needed, and the intervention necessarily involves decision-making specific to each patient, provider, and family, added Dr. McCarten. “We end up comparing a variety of interventions based on decisions made by and for persons with known dementia.”

Source: Medscape.com

Multiple effects of physical activity on molecular and cognitive signs of brain aging: can exercise slow neurodegeneration and delay Alzheimer’s disease?


Western countries are experiencing aging populations and increased longevity; thus, the incidence of dementia and Alzheimer’s disease (AD) in these countries is projected to soar. In the absence of a therapeutic drug, non-pharmacological preventative approaches are being investigated. One of these approaches is regular participation in physical activity or exercise. This paper reviews studies that have explored the relationship between physical activity and cognitive function, cognitive decline, AD/dementia risk and AD-associated biomarkers and processes. There is now strong evidence that links regular physical activity or exercise to higher cognitive function, decreased cognitive decline and reduced risk of AD or dementia. Nevertheless, these associations require further investigation, more specifically with interventional studies that include long follow-up periods. In particular, relatively little is known about the underlying mechanism(s) of the associations between physical activity and AD neuropathology; clearly this is an area in need of further research, particularly in human populations. Although benefits of physical activity or exercise are clearly recognised, there is a need to clarify how much physical activity provides the greatest benefit and also whether people of different genotypes require tailored exercise regimes.

Source: Nature

 

 

 

Cardiac disease linked to mild cognitive impairment.


Cardiac disease is associated with increased risk of mild cognitive impairment such as problems with language, thinking and judgment, according to a study.
The study by researchers with the Mayo Clinic found the connection was significant in women with heart disease more so than in men.

Known as nonamnestic because it does not include memory loss, this type of mild cognitive impairment may be a precursor to vascular and other non-Alzheimer’s dementias, the researchers noted. Mild cognitive impairment is an important stage for early detection and intervention in dementia, said Rosebud Roberts, MB, ChB, the study’s lead author and a health sciences researcher at the Mayo Clinic.

“Prevention and management of cardiac disease and vascular risk factors are likely to reduce the risk,” Roberts said in a news release.

The researchers evaluated 2,719 people ages 70 to 89 at the beginning of the study and every 15 months after. Of the 1,450 without mild cognitive impairment at the beginning, 669 had heart disease and 59 (8.8%) developed nonamenestic mild cognitive impairment. In comparison 34 (4.4%) of 781 who did not have heart disease developed nonamenestic mild cognitive impairment.

The association varied by sex, with cardiac disease and mild cognitive impairment appearing together more often among women than men.

Source: JAMA

 

 

Prevalence, Distribution, and Impact of Mild Cognitive Impairment in Latin America, China, and India: A 10/66 Population-Based Study.


Rapid demographic ageing is a growing public health issue in many low- and middle-income countries (LAMICs). Mild cognitive impairment (MCI) is a construct frequently used to define groups of people who may be at risk of developing dementia, crucial for targeting preventative interventions. However, little is known about the prevalence or impact of MCI in LAMIC settings.

Methods and Findings

Data were analysed from cross-sectional surveys established by the 10/66 Dementia Research Group and carried out in Cuba, Dominican Republic, Peru, Mexico, Venezuela, Puerto Rico, China, and India on 15,376 individuals aged 65+ without dementia. Standardised assessments of mental and physical health, and cognitive function were carried out including informant interviews. An algorithm was developed to define Mayo Clinic amnestic MCI (aMCI). Disability (12-item World Health Organization disability assessment schedule [WHODAS]) and informant-reported neuropsychiatric symptoms (neuropsychiatric inventory [NPI-Q]) were measured. After adjustment, aMCI was associated with disability, anxiety, apathy, and irritability (but not depression); between-country heterogeneity in these associations was only significant for disability. The crude prevalence of aMCI ranged from 0.8% in China to 4.3% in India. Country differences changed little (range 0.6%–4.6%) after standardization for age, gender, and education level. In pooled estimates, aMCI was modestly associated with male gender and fewer assets but was not associated with age or education. There was no significant between-country variation in these demographic associations.

Conclusions

An algorithm-derived diagnosis of aMCI showed few sociodemographic associations but was consistently associated with higher disability and neuropsychiatric symptoms in addition to showing substantial variation in prevalence across LAMIC populations. Longitudinal data are needed to confirm findings—in particular, to investigate the predictive validity of aMCI in these settings and risk/protective factors for progression to dementia; however, the large number affected has important implications in these rapidly ageing settings.

Source:PLOS

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