Archive for July 3rd, 2008

Almost half of all women in their 90s are suffering from dementia, Californian research suggests.


The analysis of more than 900 people aged 90 or over, published in the journal Neurology, found it was far less likely in men of the same age.


The reasons are not clear – although older women are more prone to stroke and heart disease, both risk factors for dementia.


There are fears dementia could place a great strain on health services.


There have been few studies looking specifically at dementia in very old people, even though increases in life-expectancy mean that this is a fast-growing group.


Other studies have shown that dementia prevalence increases for both men and women between the ages of 65 and 85.


However, the Californian research found that the likelihood of having dementia doubled every five years in women after reaching 90, but not in men.


A total of 45% of the women had dementia, compared with 28% of men. It also suggested that women who had received higher education were much less likely to develop dementia than those with a lower level of education.


Care bill


Dr Maria Corrada, who led the study, said: “As more and more people reach age 90, our findings provide further evidence that more needs to be done to provide adequate resources to care for the increasing number of very old people with memory problems.”


A recent report by the King’s Fund suggested that the burden of dementia in the UK was likely to rise sharply over the next two decades as the population aged.


The total bill for care, it predicted, would more than double to over £35 billion a year, as the number of people with the illness rises past 900,000.


The Alzheimer’s Society said, with this in mind, there was now an urgent need to find out more about how gender affected the likelihood of dementia.


A spokesman said: “Previous research has suggested that, as they get older, women are more prone to stroke and heart disease.


“Both of these are risk factors for dementia so this may go some way in explaining the difference.”


(Source:  http://news.bbc.co.uk/go/pr/fr/-/2/hi/health/7485455.stm – Published 2July 2008)


Read Full Post »

Mice given the equivalent of six to eight cups of coffee a day were less likely to develop a disease similar to multiple sclerosis, a study found.


Researchers hope this could lead to new ways to prevent MS in humans.


The Proceedings of the National Academy of Sciences journal reported that the caffeine appeared to prevent nervous system damage.


However, experts recommend no more than five cups a day, amid evidence higher doses can worsen diabetes.


While the chain reaction which leads to multiple sclerosis is still not fully understood, a key moment surrounds the entry of immune cells into the central nervous system.


Once there, they trigger “autoimmune” attacks, gradually and progressively destroying the fatty myelin sheaths that protect nerves.


Current treatments for MS are limited only to slowing the progress of the disease once it is established.


At Cornell University in the US, and Turku University in Finland, the researchers are using a mouse disease called “experimental autoimmune encephalomyelitis”, or EAE, to mimic the development of MS in humans.


One of the effects of caffeine in both mice and humans affects a molecule called adenosine, which plays a role in sleep and energy production.


When mice were dosed with caffeine, adenosine could not link to a particular receptor on the surface of cells.


This in turn appeared to have an indirect effect on the ability of immune cells to enter the nervous system at a part of the brain called the choroid plexus, and the mice did not develop EAE.


While the precise reason this happened was not clear, the researchers suggested the adenosine blocking effect led to a lower number of “adhesion molecules” – needed by the immune cells to gain entry – on the surface of the choroid plexus.


Risks and benefits


Dr Linda Thompson, who led the study, said that the next step was to see if humans who drank plenty of coffee showed any signs of being less prone to MS.


“If you found a correlation between caffeine intake and reduced MS symptoms, that would point to further studies in humans.”


However, even if this were established, coffee might not be a good way to prevent MS.


The six to eight cups given to the mice is above the limit set by the Department of Health.


Other research has suggested that it might be physically addictive at these levels, and might worsen the control of type II diabetes, a far more common disease of older people.


A spokesman for the MS Society was also cautious: “Over the years there have been numerous discoveries that have prevented EAE in mice but turning this into effective therapies for humans remains a challenge.


“Based on the results of this study, we wouldn’t advise people to change their caffeine intake.”


(Source:  http://news.bbc.co.uk/go/pr/fr/-/2/hi/health/7481023.stm – Published 20 June 2008)

Read Full Post »

Too little of one type of cholesterol has been linked by research to memory loss and Alzheimer’s disease.

UK and French scientists studied 3,673 civil servants, revealing low levels of “good” cholesterol were associated with poor memory.

Doctors might be able to uncover high-risk patients using blood tests, they said in a US heart journal.

But other experts said the study did not yet support larger diet trials aiming to boost levels.

The relationship between levels of HDL, or “good”, and LDL, or “bad” types of cholesterol is thought to be important in the development of other serious conditions such as heart disease and stroke.

Higher levels of HDL, in particular, are believed to protect against damage to blood supply caused by the narrowing of the arteries.

There is also evidence that “good” cholesterol can influence the laying down of the beta-amyloid “plaques” that are a distinctive feature in the brains of Alzheimer’s patients.

Regular exercise and eating less saturated fat, while eating more “healthy” fats such as olive oils, can boost levels.

The researchers, from University College London and the INSERM institute in France, used data from the Whitehall II trial – a collection of thousands of civil servants, to see what influence it might have over memory within a five-year period.

They took blood samples at the start of the study, and gauged word recall with a simple test. That was repeated again at the end of the study.

The researchers found that people with low levels of HDL were 53% more likely to suffer memory loss compared with the people with the highest levels of HDL.

People with impaired memory have a much greater risk of going on to develop dementia later in life.

Early sign

Dr Archarna Singh-Manoux, who led the study, said: “Memory problems are key in the diagnosis of dementia.

“This suggests that low HDL cholesterol might also be a risk factor for dementia.”

She said that doctors should be encouraged to monitor HDL levels in order to predict dementia risk.

However, an editorial in the same journal, Arteriosclerosis, Thrombosis, and Vascular Biology, by Dr Anatol Kontush and Dr John Chapman, from INSERM and the Universite Pierre and Marie Curie in Paris, said that the study did not prove that low HDL could cause memory loss, or high HDL protect against it.

“Unfortunate results in large interventional trials with dietary antioxidants suggest that we should remain cautious when proposing therapeutic intervention,” they wrote.

Dr Susanne Sorenson, from the Alzheimer’s Society, said HDL cholesterol was believed to transport harmful cholesterol from the arteries back to the liver to be degraded.

“This study shows that if there is not enough HDL to transport cholesterol and other lipids around the body, it can not only increase your risk of heart disease but also affect your memory and may increase your risk of getting Alzheimer’s disease.

“We know that controlling cholesterol in mid-life is important if you are to reduce your risk of developing vascular dementia later and this may also be important for the development of Alzheimer’s disease.”

(Source: http://news.bbc.co.uk/go/pr/fr/-/2/hi/health/7481818.stm)

Read Full Post »

Study in older women found friends, family helped minds stay sharp

(Source: By Kathleen Doheny, HealthDay Reporter, HealthDay News June 27, 2008)

The key to a healthy mind in old age may lie in an active social life, a new study suggests.

“If you are socially engaged, you are at lower risk of dementia,” said Dr. Valerie C. Crooks, a researcher at the Department of Research and Evaluation, Kaiser Permanente Southern California.

During her study, which followed more than 2,200 women ages 78 and older for four years, those with large social networks reduced their risk of getting dementia by 26 percent, she said.

Previous studies about the association between social engagement with family and friends and cognitive functioning in old age have yielded mixed results, Crooks noted. For example, “there were studies that said being married is helpful, and studies that said being married is not so helpful,” she said.

In recent studies, social contact has been generally found to be protective of cognitive functioning, however, she said.

For this new study, published in the July issue of the American Journal of Public Health, Crooks and her colleagues conducted telephone interviews with the women, all of who were members of the Kaiser Permanente HMO. The women were free of dementia when the study started in 2001.

The team tested each woman’s cognitive status by phone and reviewed her medical records to help assess it, as well. They also asked about social interactions with a spouse and/or other family and friends, including how many people they interacted with and how often.

Crooks’ team also asked the women how many people they felt they could rely on if they needed help and whether they had a person or persons they could talk to about personal issues.

At the end of the follow-up, 268 of the women had been diagnosed with dementia.

Those with larger social networks also showed a reduced risk for dementia, whose most common form is Alzheimer’s disease.

“In this study, we found marriage didn’t make a difference in terms of dementia risk,” she said. In other words, it was the social network that was protective, regardless of whether the woman was married or not.

“Those with daily contact or more had a lower risk of dementia,” she said. The contact didn’t have to be face-to-face — e-mail and telephone interaction counted, Crooks added.

It’s impossible to say how many friends and family makes up a big enough social circle to be protective, the researcher said. “Two or fewer is probably not a sufficient amount. You could have three really close friends [or family] and be fine,” Crooks speculated.

“We can’t tell you what the magic number is,” she said.

And she emphasized that her team found only an association between social networks and reduced risk of dementia, which doesn’t point to a cause-and-effect relationship, necessarily.

“There could be a person with one person [in his or her social network] who is doing perfectly fine,” she said.

While more study is needed to zero in on exactly which aspects of social support are linked with a decrease in dementia risk, Crooks said the findings make perfect sense, neurologically speaking. “The more interaction, the more you challenge your brain.”

Dr. William Thies, vice president of medical and scientific relations at the Alzheimer’s Association, said the finding “fits with a large body of evidence that being isolated is bad for you.”

But he added, the finding is merely an association, not cause and effect.

“You don’t know whether the bigger network prevents Alzheimer’s or [whether] people who don’t get Alzheimer’s maintain bigger networks,” he said.

Read Full Post »