Test Given at 8 May Predict Your Brain Health in Old Age

Amy Norton wrote . . . . . . . . .

If you were good with words and puzzles at age 8, you’re likely to fare well on tests of mental acuity at age 70, too.

That’s among the findings of a new study that followed the thinking abilities of a group of Britons born in the 1940s. Researchers found that their performance on standard cognitive tests at age 8 predicted their performance around age 70. People who scored in the top quarter as kids were likely to remain in that bracket later in life.

“Cognition” refers to our ability to pay attention, process information, commit things to memory, to reason and to solve problems.

And it’s no surprise, experts said, that there is a correlation between childhood and adulthood skills.

However, no one is saying that your brain-health destiny is set in childhood, according to senior researcher Dr. Jonathan Schott, a professor of neurology at University College London.

In this study, for example, education also mattered. Older adults who’d gone further in their formal education tended to score higher, regardless of their test performance as children.

A number of past studies have linked higher education levels to a lower risk of dementia. And the new findings bolster that evidence, said Rebecca Edelmayer, director of scientific engagement at the Alzheimer’s Association.

“It’s really unique to have data like this, from a cohort that was followed for 60 years,” said Edelmayer, who was not involved in the study.

Why would education matter in dementia risk? It’s not certain, but Dr. Glen Finney, a fellow of the American Academy of Neurology, explained the “cognitive reserve” theory: Dementia is marked by the buildup of abnormal proteins known as “plaques” and “tangles.” In people with more education, the brain might be better equipped to compensate for such damage, allowing it to function normally for a longer period.

It’s also thought that mental engagement later in life might hold similar benefits. That could mean “challenging yourself to learn something completely new” — like studying an instrument or a foreign language, said Finney, who directs the Geisinger Health System’s Memory and Cognition Program in Wilkes-Barre, Pa. He was also not part of the study.

Beyond education, Finney noted, there is a body of evidence that other lifestyle factors are important in healthy brain aging. Blood pressure control is one, he said.

Finney pointed to a recent clinical trial finding that intensive treatment of high blood pressure lowered older adults’ risk of developing mild cognitive impairment.

That refers to subtler problems with memory and thinking that may precede dementia.

In general, the same things that protect the heart — exercise, controlling cholesterol and blood sugar, and a healthy diet — are also believed to be good for the brain, Edelmayer said.

“We just don’t know yet what the best recipe is for [dementia] risk reduction,” she said.

The current findings were published in Neurology. They’re based on more than 500 U.K. adults born in 1946. When they were 8 years old, they took tests of reading comprehension and other skills. When they were around age 70, they were tested for skills like memory and information processing.

They also underwent PET scans to detect any buildup of plaques in the brain.

It turned out that among participants who tested “cognitively normal,” about 18% did have signs of plaques in their brains. And on average, their test scores were lower, versus participants with no evidence of plaques.

That does not mean those people are destined to develop dementia, Edelmayer pointed out.

However, the findings do support a growing belief among researchers, according to Schott.

The fact that plaques exert subtle influences on mental performance even in people without symptoms is noteworthy. This “provides more evidence for the growing view that when disease-modifying therapies become available, they may have maximum benefits when given very early — and ideally prior to symptom onset,” Schott said.

How would that be done? In the future, Edelmayer said, it might be possible to use certain biological “markers” — such as plaques seen in brain scans — to identify people who are on a trajectory toward dementia.

“But we’re not there yet,” she stressed. “There’s a lot of work to be done.”

According to the Alzheimer’s Association, 5.8 million Americans are living with Alzheimer’s disease — a number that is expected to balloon to nearly 14 million by 2050.

Source: HealthDay

Deep Sleep May ‘Rinse’ Day’s Toxins From Brain

Amy Norton wrote . . . . . . . . .

The deep stages of sleep may give the brain a chance to wash itself free of potentially toxic substances, a new study suggests.

Researchers found that during deep sleep, the “slow-wave” activity of nerve cells appears to make room for cerebral spinal fluid to rhythmically move in and out of the brain — a process believed to rinse out metabolic waste products.

Those waste products include beta-amyloid — a protein that clumps abnormally in the brains of people with dementia, said researcher Laura Lewis, an assistant professor of biomedical engineering at Boston University.

Lewis stressed that the findings, reported in the Nov. 1 issue of Science, do not prove that deep sleep helps ward off dementia or other diseases.

But the ultimate goal of research like this is to understand why poor sleep quality is linked to higher risks of various chronic conditions, from dementia to heart disease to depression, she said.

Researchers have known that cerebral spinal fluid, or CSF, helps clear metabolic byproducts from the brain, so that they do not build up there. They’ve also known that the process appears to amp up during sleep. But various “hows” and “whys” remained.

So the investigators recruited 11 healthy adults for a sleep study using noninvasive techniques: advanced MRI to monitor fluid flow in the brain, and electroencephalograms to gauge electrical activity in brain cells.

Sleep is marked by REM and non-REM cycles. During REM sleep, breathing and heart rates are relatively higher, and people often have vivid dreams. Non-REM sleep includes stages of deep — or slow-wave — sleep. During those stages, there’s a slow-down in brain cell activity, heart rate and blood flow, and research has found that deep sleep may aid memory consolidation and allow the brain to recover from the daily grind.

“There are all these fundamental things your brain is taking care of during deep sleep,” Lewis said.

Her team found that housecleaning may be one. When study participants were in deep sleep, each pulse in slow-wave brain activity was followed by oscillations in blood flow and volume, which allowed CSF to flow into fluid-filled cavities in the central brain.

CSF moved in “large, pulsing waves” that were seen only during deep sleep, Lewis explained.

Based on what’s known about the work of CSF, experts said it’s reasonable to conclude that slow-wave sleep promotes the flushing of waste from the brain.

The study “elegantly” illustrates the importance of deep sleep, according to Dr. Phyllis Zee, a sleep medicine specialist not involved in the work.

It “helps to explain how and why sleep is important for keeping neurons healthy — facilitating the removal of toxic molecules,” said Zee, a professor of neurology at Northwestern University Feinberg School of Medicine, in Chicago.

“One can think of sleep as a top way to take care of your brain,” she said.

Another sleep medicine specialist agreed. “There is growing evidence, with this study and others, that sleep plays a role in clearing toxins from the brain,” said Dr. Raman Malhotra, an associate professor of neurology at Washington University in St. Louis.

Other research has suggested that sleep loss can promote the buildup of “unwanted proteins” in the brain, said Malhotra, who also serves on the board of directors of the American Academy of Sleep Medicine.

A recent government study, for instance, found that one night of sleep deprivation triggered an increase in beta-amyloid in the brains of healthy adults.

“As we learn more about this role of sleep,” Malhotra said, “it may help explain why individuals who don’t get enough sleep, or suffer from sleep disorders, are at higher risk of certain chronic health conditions.”

The latest study involved younger adults with no health problems. Lewis said that it will be important to find out whether healthy older adults, or people with certain health conditions, show any differences in CSF dynamics during deep sleep.

A big question for future research, she said, will be whether alterations in those dynamics precede the development of disease.

Source: HealthDay


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Study: What’s Good for the Heart is Good for the Brain

Emory University researchers are giving us double the reasons to pay attention to our cardiovascular health — showing in a recently published study in the Journal of Alzheimer’s Disease that good heart health can equal good brain health.

The American Heart Association defines ideal cardiovascular health (CVH) across seven modifiable risk factors (blood sugar, serum cholesterol, blood pressure, body mass index, physical activity, diet and cigarette smoking). Higher CVH scores point to better heart health and lower risk for cardiovascular disease (CVD).

Prior studies have indicated that ideal CVH also benefits brain health and cognitive aging. However, it was unclear how genes and/or environment played into the relationship between cardiovascular risk factors and cognitive decline.

By studying pairs of twin brothers from the Vietnam Era Twin (VET) registry, researchers were able to observe the relationship between CVH and cognitive performance across all participants that may be explained by genetics and/or exposures or behaviors that are shared by members of the same family.

Twin studies are a special type of epidemiological study that allow researchers to examine the overall role of genes and environment in a behavioral trait or disorder. Identical twins share 100 percent of their genetic material, while fraternal twins share on average 50 percent of genetic material. For a given trait or medical condition, any excess similarity between identical twins compared with fraternal twins, is likely suggestive of genes rather than environment. Twin studies can serve to differentiate between “nature vs. nurture.”

“Our study across the entire sample of twins confirmed that better CVH is associated with better cognitive health in several domains,” says senior author Viola Vaccarino, MD, PhD, Wilton Looney Professor of Cardiovascular Research, Rollins School of Public Health, and professor, division of cardiology, Emory University School of Medicine. “The analyses further suggested that familial factors shared by the twins explain a large part of the association and thus could be important for both cardiovascular and brain health.”

To determine whether these familial factors were genetically or environmentally driven, researchers further stratified the within-pair analysis to determine whether the relationship between CVH and cognitive function was different between identical and fraternal twins.

The within-pair association was similar in identical and fraternal twins. Therefore familial factors, such as early family environment, early socioeconomic status and education, and parenting — rather than genetics — may be important precursors of both cardiovascular and brain health — thus explaining some of the association between CVH and cognition.

“Improving population-level CVH scores, which are extremely low in the United States, has the potential to reduce the burden of dementia along with heart disease,” says study co-author Ambar Kulshreshtha, MD, PhD, assistant professor of family and preventive medicine, Emory University School of Medicine. “Because CVH factors are modifiable, prevention of cardiovascular risk factors and promotion of a healthy lifestyle beginning early in life should achieve the best results for promoting not only cardiovascular health, but also cognitive health.”

Source: Science Daily


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Artificial Intelligence Beats Some Radiologists at Spotting Bleeds in the Brain

Dennis Thompson wrote . . . . . . . . .

Computer-driven artificial intelligence (AI) can help protect human brains from the damage wrought by stroke, a new report suggests.

A computer program trained to look for bleeding in the brain outperformed two of four certified radiologists, finding abnormalities in brain scans quickly and efficiently, the researchers reported.

“This AI can evaluate the whole head in one second,” said senior researcher Dr. Esther Yuh, an associate professor of radiology at the University of California, San Francisco. “We trained it to be very, very good at looking for the kind of tiny abnormalities that radiologists look for.”

Stroke doctors often say that “time is brain,” meaning that every second’s delay in treating a stroke results in more brain cells dying and the patient becoming further incapacitated.

Yuh and her colleagues hope that AI programmed to find trouble spots in a brain will be able to significantly cut down treatment time for stroke patients.

“Instead of having a delay of 20 to 30 minutes for a radiologist to turn around a CT scan for interpretation, the computer can read it in a second,” Yuh said.

Stroke is the fifth-leading cause of death in the United States, and is a leading cause of disability, according to the American Stroke Association.

There are two types of strokes: ones caused by burst blood vessels in the brain (hemorrhagic), and others that occur when a blood vessel becomes blocked (ischemic).

Yuh’s AI still needs to be tested in clinical trials and approved by the U.S. Food and Drug Administration, but other programs are already helping doctors speed up stroke treatment, said Dr. Christopher Kellner. He is director of the Intracerebral Hemorrhage Program at Mount Sinai, in New York City.

“We are already using AI-driven software to automatically inform us when certain CAT scan findings occur,” he said. “It’s already become, in just the last year, an essential part of our stroke work-up.”

An AI created by a company called Viz.ai is being used at Mount Sinai to detect blood clots that have caused a stroke by blocking the flow of blood to the brain, Kellner said.

Yuh and her team used a library of nearly 4,440 CT scans to train their AI to look for brain bleeding.

These scans are not easy to read, she said. They are low-contrast black-and-white images full of visual “noise.”

“It takes a lot of training to be able to read these — doctors train for years to be able to read these correctly,” Yuh said.

Her team trained its algorithm to the point that it could trace detailed outlines of abnormalities it found, demonstrating their location in a 3-D model of the brain being scanned.

They then tested the algorithm against four board-certified radiologists, using a series of 200 randomly selected head CT scans.

The AI slightly outperformed two radiologists, and slightly underperformed against the other two, Yuh said.

The AI found some small abnormalities that the experts missed. It also provided detailed information that doctors would need to determine the best treatment.

The computer program also provided this information with an acceptable level of false positives, Yuh said. That would minimize how much time doctors would need to spend reviewing its results.

Yuh suspects radiologists always will be needed to double-check the AI, but Kellner isn’t so sure.

“There will definitely be a point where there’s no human involved in the evaluation of the scans, and I think that’s not too far off, honestly,” he said. “I think, ultimately, a computer will be able to scan that faster and send out an alert faster than a human can.”

The new study was published in the Proceedings of the National Academy of Sciences.

Source: HealthDay


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Drug Limits Damage of Brain Injury

Many brain injury deaths could be prevented by using an inexpensive drug in the critical hours following a head trauma, a new international study finds.

“Traumatic brain injury can happen to anyone at any time, whether it’s through an incident like a car crash or simply falling down the stairs,” said study co-leader Ian Roberts, a professor of clinical trials at the London School of Hygiene & Tropical Medicine.

“We believe that if our findings are widely implemented, they will boost the chances of people surviving head injuries in both high-income and low-income countries around the world,” Roberts added.

For the study, researchers assessed the use of tranexamic acid (TXA), which prevents bleeding into the brain by inhibiting blood clot breakdown, in traumatic brain injury patients.

The 12,000 patients at 175 hospitals in 29 countries received either intravenous TXA or an inactive placebo.

Treatment with TXA within three hours of brain injury reduced the risk of death, the investigators found. The benefits were greatest in patients with mild and moderate brain injury (20% reduction in deaths), while there was no clear survival benefit seen in patients with the most severe brain injuries.

In addition, there was no evidence of harmful side effects and no increase in disability in survivors who received TXA, according to the study.

“We already know that rapid administration of tranexamic acid can save lives in patients with life-threatening bleeding in the chest or abdomen, such as we often see in victims of traffic crashes, shootings or stabbings,” Roberts said in a university news release.

“This hugely exciting new result shows that early treatment with TXA also cuts deaths from head injury,” he added. “It’s an important breakthrough and the first neuroprotective drug for patients with head injury.”

The findings were published in The Lancet.

Traumatic brain injury is a leading cause of death and disability worldwide, with an estimated 69 million new cases each year, the study authors noted.

While TXA can prevent brain bleeding from getting worse, it can’t repair damage already done, so early treatment is critical. There was a 10% reduction in effectiveness for every 20-minute delay, the researchers found.

Study co-author Antoni Belli said, “This is a landmark study. After decades of research and many unsuccessful attempts, this is the first ever clinical trial to show that a drug can reduce mortality after traumatic brain injury.” Belli is a professor of trauma neurosurgery at the University of Birmingham, in the United Kingdom.

“Not only do we think this could save hundreds of thousands of lives worldwide, but it will no doubt renew the enthusiasm for drug discovery research for this devastating condition,” Belli said.

Source: HealthDay


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