Blood pressure and cognitive decline

High blood pressure as an adult may indicate a weaker brain with more cognitive decline later in life.

Let your blood pressure get too high in midlife, and you might pay the price in mental decline later on, a new study suggests.

The study of almost 14,000 people found that high blood pressure in those aged 48 to 67 was tied to a late-life drop in mental ability. Over 20 years, people with high blood pressure in midlife experienced a modest but significant 6.5 percent decline in scores on tests of mental function, compared with people with normal blood pressure.

"High blood pressure might be an important risk factor for dementia, since mental decline is a known risk factor," said lead researcher Dr. Rebecca Gottesman, an associate professor of neurology and epidemiology at Johns Hopkins University School of Medicine in Baltimore.

However, she stressed that because "we know how to treat high blood pressure," bringing it under control might also cut a person's risk for dementia.

For the study, Gottesman's team collected data on people taking part in a major U.S. heart disease study. The participants were followed for as long as 23 years and their mental abilities were tested three separate times.

Gottesman's group found that people whose blood pressure was controlled with medication had less mental decline than those with uncontrolled high blood pressure. The effect was stronger among whites than blacks, the researchers noted.

Blood pressure levels in middle age may be especially important to later-life mental acuity, Gottesman said.

"This may be why some clinical trials that have studied the role of blood pressure medications [in older people] have failed to find a benefit in reducing mental decline and dementia," she reasoned. "The trials may simply not be long enough -- it may be most important to start treatment of high blood pressure when people are middle-aged."

However, the jury is still out on whether blood pressure medication given in middle age can help boost late-life thinking and memory.

"In our study, people who were on medications to treat high blood pressure did have less mental decline than did people not on medications," Gottesman said. "But it's possible those people had been on medications for years."

Still, "our data suggest that, overall, being on any medications for high blood pressure may be protective," Gottesman said.

The report was published online Aug. 4 in JAMA Neurology.

Dr. Philip Gorelick is medical director of the Hauenstein Neuroscience Center at Michigan State University College of Human Medicine in Grand Rapids.

He believes that the new study "provides some evidence that those who were observed and treated for high blood pressure were better off in the long run from a mental standpoint than those who were not treated for high blood pressure."

Gorelick, who authored an accompanying journal editorial, said that doctors have long known that treating high blood pressure is key to cutting people's odds for stroke and heart attack.

Now "another, but less well-documented benefit, of blood pressure lowering may be the preservation of mental function as we age," he said. "With additional study, we may be better positioned to tell our patients whether control of blood pressure not only prevents stroke and heart attack, but also helps to preserve their brain."

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Less sleep may mean faster brain aging for older adults

When older adults get less sleep, it may mean their brains age faster according to a recent study.

Researchers at Duke-NUS Graduate Medical School Singapore (Duke-NUS) have found evidence that the less older adults sleep, the faster their brains age. These findings, relevant in the context of Singapore's rapidly ageing society, pave the way for future work on sleep loss and its contribution to cognitive decline, including dementia.

Past research has examined the impact of sleep duration on cognitive functions in older adults. Though faster brain ventricle enlargement is a marker for cognitive decline and the development of neurodegenerative diseases such as Alzheimer's, the effects of sleep on this marker have never been measured.

The Duke-NUS study examined the data of 66 older Chinese adults, from the Singapore-Longitudinal Aging Brain Study(1). Participants underwent structural MRI brain scans measuring brain volume and neuropsychological assessments testing cognitive function every two years. Additionally, their sleep duration was recorded through a questionnaire. Those who slept fewer hours showed evidence of faster ventricle enlargement and decline in cognitive performance.

"Our findings relate short sleep to a marker of brain aging," said Dr June Lo, the lead author and a Duke-NUS Research Fellow. "Work done elsewhere suggests that seven hours a day(2) for adults seems to be the sweet spot for optimal performance on computer based cognitive tests. In coming years we hope to determine what's good for cardio-metabolic and long term brain health too," added Professor Michael Chee, senior author and Director of the Centre for Cognitive Neuroscience at Duke-NUS.

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Study: Poor sleep is linked to cognitive decline in older men

A study found that poor sleep quality in old men is liked to their cognitive decline over a few years.

A new study of older men found a link between poor sleep quality and the development of cognitive decline over three to four years.

Results show that higher levels of fragmented sleep and lower sleep efficiency were associated with a 40 to 50 percent increase in the odds of clinically significant decline in executive function, which was similar in magnitude to the effect of a five-year increase in age. In contrast, sleep duration was not related to subsequent cognitive decline.

"It was the quality of sleep that predicted future cognitive decline in this study, not the quantity," said lead author Terri Blackwell, MA, senior statistician at the California Pacific Medical Center Research Institute (CPMCRI) in San Francisco, Calif. "With the rate of cognitive impairment increasing and the high prevalence of sleep problems in the elderly, it is important to determine prospective associations with sleep and cognitive decline."

The study involved 2,822 community-dwelling older men at six clinical centers in the U.S. Participants had a mean age of 76 years. The study is published in the April 1 issue of the journal Sleep.

"This study provides an important reminder that healthy sleep involves both the quantity and quality of sleep," said American Academy of Sleep Medicine President Dr. M. Safwan Badr. "As one of the pillars of a healthy lifestyle, sleep is essential for optimal cognitive functioning."

The population-based, longitudinal study was conducted by a research team led by Dr. Katie Stone, senior scientist at CPMCRI in San Francisco, Calif. Institutions represented by study collaborators include the University of California, San Francisco; University of California, San Diego; Harvard Medical School; University of Minnesota; and several Veterans Affairs medical centers.

An average of five nights of objective sleep data were collected from each participant using a wrist actigraph. Cognitive function assessment included evaluation of attention and executive function using the Trails B test. According to the authors, executive function is the ability for planning or decision making, error correction or trouble shooting, and abstract thinking. Results were adjusted for potential confounding factors such as depressive symptoms, comorbidities and medication use.

The underlying mechanisms relating disturbed sleep to cognitive decline remain unknown, the authors noted. They added that additional research is needed to determine if these associations hold after a longer follow-up period.

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Health link between the heart and the brain

This article discusses the link between risk factors of heart disease and declining brain function.

Heart disease risk factors can lead to a decline in brain function in both younger and older adults, Dutch researchers report.

The new study included nearly 3,800 people, aged 35 to 82, who were checked for heart disease risk factors such as smoking, diabetes and high levels of "bad" cholesterol, and given tests to assess their memory and mental skills such as the ability to plan and reason and to begin and switch tasks.

Those with the highest risk for heart disease did 50 percent worse on the mental tests than those with the lowest risk. Two heart disease risk factors -- smoking and diabetes -- were especially associated with poorer brain function, according to the study in the May 2 issue of the journal Stroke.

The link between heart disease risk factors and reduced brain function was seen in all age groups, the investigators noted.

"Young adults may think the consequences of smoking or being overweight are years down the road, but they aren't," study author Dr. Hanneke Joosten, a nephrology fellow at the University Medical Center in Groningen, the Netherlands, said in a journal news release.

"Most people know the negative effects of heart risk factors such as heart attack, stroke and [kidney] impairment, but they do not realize it affects cognitive [mental] health. What's bad for the heart is also bad for the brain," Joosten added.

She said doctors need to be aware of this link between heart disease risk factors and brain function decline, and more public action is needed to reduce heart disease risk factors.

"Smoking cessation programs might not only prevent cancer, stroke and cardiovascular events, but also cognitive [mental] damage," Joosten said.

The association between heart risk factors and poorer brain function seen in the study does not prove a cause-and-effect relationship.

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Brain "Pacemaker" Implanted to Help Mitigate Alzheimer's Symptoms

I will watch this research. It may be helpful for adults with Trisomy 21/ Down Syndrome in the future. JR

Researchers have implanted a 'pacemaker' in a patient's brain who is in the early stages of Alzheimers. The hope is that the pacemaker will help alleviate the symptoms of Alzheimers and reverse cognitive decline.

Researchers at Johns Hopkins Medicine in November surgically implanted a pacemaker-like device into the brain of a patient in the early stages of Alzheimer's disease, the first such operation in the United States. The device, which provides deep brain stimulation and has been used in thousands of people with Parkinson's disease, is seen as a possible means of boosting memory and reversing cognitive decline.

The surgery is part of a federally funded, multicenter clinical trial marking a new direction in clinical research designed to slow or halt the ravages of the disease, which slowly robs its mostly elderly victims of a lifetime of memories and the ability to perform the simplest of daily tasks, researchers at Johns Hopkins say. Instead of focusing on drug treatments, many of which have failed in recent clinical trials, the research focuses on the use of the low-voltage electrical charges delivered directly to the brain. There is no cure for Alzheimer's disease.

As part of a preliminary safety study in 2010, the devices were implanted in six Alzheimer's disease patients in Canada. Researchers found that patients with mild forms of the disorder showed sustained increases in glucose metabolism, an indicator of neuronal activity, over a 13-month period. Most Alzheimer's disease patients show decreases in glucose metabolism over the same period.

The first U.S. patient in the new trial underwent surgery at The Johns Hopkins Hospital, and a second patient is scheduled for the same procedure in December. The surgeries at Johns Hopkins are being performed by neurosurgeon William S. Anderson, M.D.

"Recent failures in Alzheimer's disease trials using drugs such as those designed to reduce the buildup of beta amyloid plaques in the brain have sharpened the need for alternative strategies," says Paul B. Rosenberg, M.D., an associate professor of psychiatry and behavioral sciences at the Johns Hopkins University School of Medicine, and site director of the trial's Johns Hopkins location. "This is a very different approach, whereby we are trying to enhance the function of the brain mechanically. It's a whole new avenue for potential treatment for a disease becoming all the more common with the aging of the population."

Some 40 patients are expected to receive the deep brain stimulation implant over the next year or so at Johns Hopkins and four other institutions in North America as part of the ADvance Study led by Constantine G. Lyketsos, M.D., M.H.S., a professor of psychiatry and behavioral sciences at the Johns Hopkins University School of Medicine, and Andres Lozano, M.D., Ph.D., chairman of the neurology department at the University of Toronto. Only patients whose cognitive impairment is mild enough that they can decide on their own to participate will be included in the trial.

Other sites performing the operation, supported by the National Institutes of Health's National Institute on Aging (R01AG042165), are the University of Toronto, the University of Pennsylvania, the University of Florida, and Banner Health System in Phoenix, Ariz. The medical device company, Functional Neuromodulation Ltd., is also supporting the trial.

"We are very excited about the possibilities of this potentially new way to treat Alzheimer's," says Lyketsos, director of the Johns Hopkins Memory and Alzheimer's Treatment Center in Baltimore.

While experimental for Alzheimer's patients, more than 80,000 people with the neurodegenerative disorder Parkinson's disease have undergone the procedure over the past 15 years, with many reporting fewer tremors and requiring lower doses of medication afterward, Lyketsos says. Other researchers are testing deep brain stimulation to control depression and obsessive-compulsive disorder resistant to other therapies.

The surgery involves drilling holes into the skull to implant wires into the fornix on either side of the brain. The fornix is a brain pathway instrumental in bringing information to the hippocampus, the portion of the brain where learning begins and memories are made, and where the earliest symptoms of Alzheimer's appear to arise. The wires are attached to a pacemaker-like device, the "stimulator," which generates tiny electrical impulses into the brain 130 times a second. The patients don't feel the current, Rosenberg says.

For the trial, all of the patients will be implanted with the devices. Half will have their stimulators turned on two weeks after surgery, while the other half will have their stimulators turned on after one year. Neither the patients nor the doctors treating them will know which group gets an early or later start.

"Deep brain stimulation might prove to be a useful mechanism for treating Alzheimer's disease, or it might help us develop less invasive treatments based on the same mechanism," Rosenberg says.

By 2050, the number of people age 65 and older with Alzheimer's disease may triple, experts say, from 5.2 million to a projected 11 million to 16 million, unless effective treatments are found.

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Study: Migraines Linked to More Brain Lesions Among Women

Results of a new study show that women who have migraines more commonly have brain lesions, which is associated with cognitive decline.

A new study shows that women who experience migraines have shown a higher prevalence and greater increase in deep white matter hyperintensities (brain lesions) than those who do not. However, the number, frequency, and severity of the migraines the women experienced were not associated with lesion progression.

The study, published this week in theJournal of the American Medical Association, looked at the association between migraine frequency, brain lesions, and cognitive decline. 286 participants in the 2000 Cerebral Abnormalities in Migrane Epidemiological Risk Analysis were given MIR scans in 2009. Researchers found that 77% of the women in the migrane group had progression of brain lesions, compared to 60% of the control group. Among men, no association was found between migraines and brain lesions. The results were controlled for age, sex, hyper tension, diabetes, and level of education.

“In addition, the number of migraines, frequency of migraines, migraine severity, type of migraine, and migraine therapy were not associated with lesion progression,” said the study’s authors. “Increase in deep white matter hyperintensity volume was not significantly associated with poorer cognitive performance at follow-up.”

In the past, brain lesions have been associated with cognitive decline, as well as atherosclerotic disease risk factors and an increased risk of ischemic stoke. Migraines affect up to 15% fo the general population, according to the study’s authors.

“In summary, in a community-based cohort followed up for 9 years, migraine was associated only with a higher incidence of deep white matter brain changes among women,” said the study’s authors. “There were no significant associations of migraine with progression of other brain lesions among women, and there were no associations of migraine headache with progression of any brain lesions among men. These findings raise questions about the role of migraine headaches with progression of cerebral vascular changes. The functional implications of MRI brain lesions in women with migraine and their possible relation with ischemia and ischemic stroke warrant further research.”

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