Too Much Sitting, too Little Eexercise may Accelerate Biological Aging

Researchers at University of California San Diego School of Medicine report that elderly women who sit for more than 10 hours a day with low physical activity have cells that are biologically older by eight years compared to women who are less sedentary.

The study, publishing online January 18 in the American Journal of Epidemiology, found elderly women with less than 40 minutes of moderate-to-vigorous physical activity per day and who remain sedentary for more than 10 hours per day have shorter telomeres — tiny caps found on the ends of DNA strands, like the plastic tips of shoelaces, that protect chromosomes from deterioration and progressively shorten with age.

As a cell ages, its telomeres naturally shorten and fray, but health and lifestyle factors, such as obesity and smoking, may accelerate that process. Shortened telomeres are associated with cardiovascular disease, diabetes and major cancers.

“Our study found cells age faster with a sedentary lifestyle. Chronological age doesn’t always match biological age,” said Aladdin Shadyab, PhD, lead author of the study with the Department of Family Medicine and Public Health at UC San Diego School of Medicine.

Shadyab and his research team believe they are the first to objectively measure how the combination of sedentary time and exercise can impact the aging biomarker.

Nearly 1,500 women, ages 64 to 95, participated in the study. The women are part of the larger Women’s Health Initiative (WHI), a national, longitudinal study investigating the determinants of chronic diseases in postmenopausal women. The participants completed questionnaires and wore an accelerometer on their right hip for seven consecutive days during waking and sleeping hours to track their movements.

“We found that women who sat longer did not have shorter telomere length if they exercised for at least 30 minutes a day, the national recommended guideline,” said Shadyab. “Discussions about the benefits of exercise should start when we are young, and physical activity should continue to be part of our daily lives as we get older, even at 80 years old.”

Shadyab said future studies will examine how exercise relates to telomere length in younger populations and in men.

Source: EurekAlert!


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Delirium Could Accelerate Dementia-related Mental Decline

When hospitalised, people can become acutely confused and disorientated. This condition, known as delirium, affects a quarter of older patients and new research by UCL and University of Cambridge shows it may have long-lasting consequences, including accelerating the dementia process.

The study, published today in the journal JAMA Psychiatry, is the first to show the multiplying effects of delirium and dementia in these patients.

Episodes of delirium in people who are not known to have dementia, might also reveal dementia at its earliest stages, the research found.

While both delirium and dementia are important factors in cognitive decline among the elderly, delirium is preventable and treatable through dedicated geriatric care.

Further research is needed to understand exactly how delirium interacts with dementia, and how this could be blocked.

“If delirium is causing brain injury in the short and long-term, then we must increase our efforts to diagnose, prevent and treat delirium. Ultimately, targeting delirium could be a chance to delay or reduce dementia” said Dr. Daniel Davis (MRC Unit for Lifelong Health and Ageing at UCL), who led the research while at the University of Cambridge.

Scientists looked at three European populations – in Finland, Cambridge and UK-wide – and examined brain specimens in 987 people aged 65 and older. Each person’s memory, thinking and experience of delirium had been recorded over 10 years towards the end of their life.

When these were linked with pathology abnormalities due to Alzheimer’s and other dementias, those with both delirium and dementia-changes had the most severe change in memory.

Dr Davis added: “Unfortunately, most delirium goes unrecognised. In busy hospitals, a sudden change in confusion not be noticed by hospital staff. Patients can be transferred several times and staff often switch over – it requires everyone to ‘think delirium’ and identify that a patient’s brain function has changed.”

Source: EurekAlert!


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High Blood Pressure May Not Be All Bad in the Elderly: Study

Developing high blood pressure in very old age may provide some protection from dementia, a new study suggests.

In middle age, high blood pressure — also called hypertension — boosts dementia risk later in life, said study lead researcher Maria Corrada. It also raises your risk for heart attack and stroke.

But its onset in the eighth or ninth decade of life was linked to lower risk of mental decline in one’s 90s, her team found.

“Hypertension in the very old is not detrimental for mental health,” said Corrada, a professor of neurology and epidemiology at the University of California, Irvine.

Several factors may help explain the apparent association between late-life high blood pressure and lower dementia risk, Corrada said.

For one, as people age, blood pressure may need to increase to keep blood flowing to the brain for normal functioning.

“It’s a matter of creating enough pressure to get blood to oxygenate the brain adequately,” Corrada said.

The researchers said it’s also possible, but less likely, that blood pressure drops as dementia begins due to the deterioration of brain cells. This could mean that elderly people who don’t develop dementia will have higher blood pressure.

High blood pressure in the very old might have other benefits, Corrada said. “There is evidence that high blood pressure may also reduce frailty and disability,” she said.

It’s clear that age matters, Corrada said, although the study didn’t prove a cause-and-effect link between high blood pressure and reduced dementia risk.

“Whatever we know and learn about the health of the younger elderly does not necessarily apply to the health of the ‘oldest old’ — the fastest-growing segment of the population,” she said.

To avert a public health epidemic of dementia, it’s important to understand how risk for mental decline might change over time, the researchers and others said.

High blood pressure may need to be divided into at least two classes, said Dr. Sam Gandy, a New York City brain specialist.

“We usually think of the young adult onset form, which if untreated can damage heart, kidney, eye and brain blood vessels,” said Gandy, director of the Center for Cognitive Health at Mount Sinai Hospital in New York City.

A second class may be late-life hypertension, which is driven by a brain in “distress,” he said.

“This distressed brain, through neurological mechanisms, could be causing blood pressure to rise in an attempt to improve blood flow and relieve the distress,” Gandy explained.

The new findings may explain why treating late-life hypertension has recently failed to reduce dementia, added Gandy.

For the study, Corrada and her colleagues followed 559 people aged 90 and older for nearly three years. The participants were free from dementia at the start of the study.

The researchers checked blood pressure history and assessed the participants for dementia every six months during the course of the study. During follow-up, 40 percent developed dementia.

High blood pressure was defined as a systolic pressure of 140 mm Hg or greater and a diastolic pressure of 90 mm Hg or more, Corrada said. Systolic pressure is the first number in a blood pressure reading.

The researchers found that those who developed high blood pressure after age 80 were 42 percent less likely to develop dementia in their 90s compared to those with normal blood pressure. And, those whose high blood pressure started after age 90 were 63 percent less likely to develop dementia versus those without hypertension.

The link remained even if patients were taking blood pressure-lowering medications, according to the study.

These findings echo other seemingly inconsistent findings about the risk for dementia. For example, two studies have shown that people who are overweight at 75 or beyond have a lower risk for mental dysfunction, Corrada said.

It’s not completely understood why high blood pressure and heaviness might become protective in old age, said Heather Snyder, director of medical and scientific operations at the Alzheimer’s Association.

“We need to better understand the connection between the cardiovascular system and our brains,” Snyder said.

In the meantime, do what you can to maintain good heart health as you age, she added.

The report was published online in the journal Alzheimer’s & Dementia.

Source: U.S. Department of Health and Human Services


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Play an Instrument? You Probably React Faster, Too

Could learning to play a musical instrument help the elderly react faster and stay alert?

Quite likely, according to a new study by Université de Montréal’s School of Speech Language Pathology and Audiology, part of UdeM’s medical faculty.

Published in the U.S. journal Brain and Cognition, the study shows that musicians have faster reaction times to sensory stimuli than non-musicians have.

And that has implications for preventing some effects of aging, said lead researcher Simon Landry, whose study is part of his doctoral thesis in biomedical science.

“The more we know about the impact of music on really basic sensory processes, the more we can apply musical training to individuals who might have slower reaction times,” Landry said.

“As people get older, for example, we know their reaction times get slower. So if we know that playing a musical instrument increases reaction times, then maybe playing an instrument will be helpful for them.”

Click on the mouse, please

In his study, co-authored with his thesis advisor, audiology associate professor François Champoux, Landry compared the reaction times of 16 musicians and 19 non-musicians.

They were sat in a quiet, well-lit room with one hand on a computer mouse and the index finger of the other on a vibro-tactile device, a small box that vibrated intermittently.

They were told to click on the mouse when they heard a sound (a burst of white noise) from the speakers in front of them, or when the box vibrated, or when both happened.

Each of the three stimulations – audio, tactile and audio-tactile – was done 180 times. The subjects wore earplugs to mask any buzzing “audio clue” when the box vibrated.

“We found significantly faster reaction times with musicians for auditory, tactile and audio-tactile stimulations,” Landry writes in his study.

“These results suggest for the first time that long-term musical training reduces simple non-musical auditory, tactile and multisensory reaction times.”

Two instruments, not just one

The musicians were recruited from UdeM’s music faculty, started playing between ages 3 and 10, and had at least seven years of training.

There were eight pianists, 3 violinists, two percussionists, one double bassist, one harpist and one viola player. All but one (a violinist) also mastered a second instrument, or more.

The non-musicians were students at the School of Speech Language Pathology. As with the musicians, roughly half were undergraduates and half graduates.

Landry, whose research interest is in how sound and touch interact, said his study adds to previous ones that looked at how musicians’ brains process sensory illusions.

“The idea is to better understand how playing a musical instrument affects the senses in a way that is not related to music,” he said of his study.

Source: University of Montreal

The Aging Brain Benefits from Distraction

As you age, you may find it more difficult to focus on certain tasks. But while distractions can be frustrating, they may not be as bad as we think. In a review published November 15 in Trends in Cognitive Sciences, researchers at the University of Toronto and Harvard University suggest that there may be some benefits to reduced focus, especially in people over 50. Using behavioral studies and neuroimaging evidence, the researchers discuss how being easily distracted can help adults with, for example, problem solving and learning new information.

“Different types of tasks benefit from a more broad focus of attention, and this is usually seen in tasks that involve thinking creatively or using information that was previously irrelevant,” says first author Tarek Amer, a psychology Ph.D. candidate at the University of Toronto and a graduate student at the Rotman Research Institute. “The literature gives us the impression that older adults are essentially doomed as their cognitive abilities decrease, when, in reality, many older adults get along just fine in their day-to-day lives, and we think that shows that aging adults don’t always need to have high cognitive control.”

When people have high cognitive control, they are able to maintain their focused attention and ignore distractions to get things done. But Amer and his colleagues found that people with reduced cognitive control had an easier time thinking of creative solutions to problems, and they were better at noticing patterns in the world around them. These findings also indicated that older adults could outperform their younger counterparts on certain problem-solving tasks, as they were able to broaden their attention more easily. Additionally, people didn’t require high levels of cognitive control for inherent, day-to-day tasks, like walking down the street or learning new information.

In order to explore the benefits of cognitive control, many lab-based behavioral experiments require participants to complete a specific set of tasks, limiting the role of distraction. But the researchers say these experiments have shortcomings, as they don’t explore situations when distractions and reduced cognitive control could be helpful, making the conclusions fairly one sided.

“Many of the tasks that we study in classic cognitive psychology are tasks that require high cognitive control, but these assigned tasks might not accurately mirror what people do in the real world because they limit distractions,” says co-author Lynn Hasher, a professor of psychology at the University of Toronto and the Rotman Research Institute. “But a distraction in one setting can actually be useful information in another setting, and the more information you have, the better able you’re going to be to address a current problem.”

Amer and his colleagues hope to use this information to determine exactly what tasks can benefit from reduced control in order to better simulate these experiences in a lab. Although they also hope to expand the research beyond the aging population to examine how distractions can be beneficial for people with a range of cognitive impairments, for now they recognize that this understanding of cognitive control is a step closer to understanding the aging brain.

“There is a question about what really sustains performance in old age, and it’s clear that working memory alone cannot provide us with the answer to that question,” says Hasher. “But we think it’s possible that studying reduced cognitive control can help us understand how older adults can still perform independently and successfully in their lives.”

Source: Science Daily


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