Tag Archives: Alzheimer’s Research UK

Health, Medical, Research, Science

New biological marker could detect Alzheimer’s disease ten years before symptoms appear…

EARLY TEST FOR DETECTING ALZHEIMER’S

Scientists are hoping that a new test could detect Alzheimer’s disease at least a decade before symptoms appear. That would pave the way for early treatment.

Researchers have discovered that a fall in levels of a certain type of genetic material could signal an increased risk and propensity of developing Alzheimer’s.

The biological markers are found within the cerebral spinal fluid (CSF) some 10 years before signs of dementia become apparent.

There are approximately 800,000 people with dementia in the UK, and current trends suggest that one in three people over 65 will die from the degenerative disease.

Presently, the only accurate method to diagnose the disease is by post-mortem neuropathological analysis, although other functional tests (such as memory and brain tests) can be used to determine whether drugs or other forms of treatment may help.

Researchers at Spain’s CSIC Institute of Biomedical Research of Barcelona believe they may have found a biological marker that could suggest the disease process is underway before symptoms start to appear.

Scientists found a drop in the content of mitochondrial DNA (mtDNA) –genetic material present in the energy centre of cells – in spinal fluid may be a sign for the disease.

They suggest that diminishing mtDNA levels reflect the reduced ability of mitochondria to power brain cells, thus triggering their death.

The drop in the concentration of mtDNA precedes the appearance of other recognised biochemical Alzheimer’s biomarkers, suggesting the process of Alzheimer’s disease starts earlier than previously thought and that mtDNA depletion may be one of the earliest predictors.

Researchers have previously been unable to detect the genetic material in spinal fluid, but they used a new technique to amplify tiny amounts. The research study was first reported in the journal Annals of Neurology.

The researchers at CSIC now hope other labs and hospitals will be able to replicate the results.

They say by finding a way to block the degeneration, clinicians may be able to diagnose and treat the disease before symptoms even appear.

Lead author Dr Ramon Trullas, said:

… If our initial findings can be replicated by other laboratories, the results will change the way we currently think about the causes of Alzheimer’s.

… The discovery of a fall in levels of a certain type of genetic material could signal an increased risk of developing Alzheimer’s.

… This discovery may enable us to search for more effective treatments that can be administered during the pre-clinical stage.

Dr Marie Janson of Alzheimer’s Research UK, the UK’s leading dementia research charity, said:

… Problems with mitochondria have already been linked to Alzheimer’s, which is why Alzheimer’s Research UK is currently funding research to further examine this link.

… This small study suggests that decreased mitochondrial DNA in cerebrospinal fluid may indicate the earliest stages of Alzheimer’s, but more work is needed to confirm this in larger groups of people.

… It would be useful to see further studies investigate changes in mitochondrial DNA over time, to determine how long before symptoms such changes might be detected.

… We know Alzheimer’s begins to develop before symptoms appear, and the ability to detect the disease at this stage is crucial for recruiting the right people for clinical trials of potential new treatments.

 

The discovery of a fall in levels of a certain type of genetic material could signal an increased risk of developing Alzheimer's disease. Image shows a CT scan of the brain of someone with Alzheimer's.

The discovery of a fall in levels of a certain type of genetic material could signal an increased risk of developing Alzheimer’s disease. Image shows a CT scan of the brain of someone with Alzheimer’s.

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Health, Medical, Research, Science

ACE inhibitors may boost brainpower…

BLOOD PRESSURE DRUGS

Scientists and medical practitioners have long recognised that taking blood pressure drugs may slow the onset of Alzheimer’s.

But, now, researchers have uncovered evidence that the drugs, known as ACE inhibiters, may actually boost brainpower.

Those with high blood pressure are more at risk of developing Alzheimer’s and similar diseases, but the study found their memory and thinking skills were protected by the drugs they were taking.

ACE inhibitors – medicines which include ramipril, captopril and perindopril – have become increasingly popular over the past decade, particularly for younger patients.

Researchers in Ireland and Canada investigated drugs which target a specific biochemical pathway called the renin angiotensin system – a hormone system which is thought to affect the development of Alzheimer’s.

The study by researchers compared the rate of cognitive decline in 361 patients diagnosed with Alzheimer’s disease, vascular dementia (caused by problems in the blood supply to the brain), or a mix of both. Of that group, 85 were already taking ACE inhibitors; the rest were not.

Also analysed was the impact on 30 patients, with an average age of 77, who were taking the drugs for the first time.

The patients were assessed over six months, using the Standardised Mini Mental State Examination or the Quick Mild Cognitive Impairment tests.

The study found that those taking ACE inhibitors experienced marginally slower rates of cognitive decline than those who were not. The findings were first disclosed in the journal BMJ Open.

Scientists from University College Cork in Ireland and McMaster University in Ontario also found that the brainpower of those patients who had been newly prescribed ACE inhibitors actually improved. This suggests for the first time that such drugs may not only halt cognitive decline, but may actually improve brainpower.

The researchers said:

… Although the differences were small and of uncertain clinical significance, if sustained over years, compounding effects may well have significant clinical benefits.

They warn that ACE inhibitors are harmful to some patients, so if wider and larger studies confirm they work well in dementia, it may be only certain people with high blood pressure who stand to benefit.

Previous studies have linked other forms of blood pressure medication with anti-dementia benefits.

A statement issued by the Alzheimer Society, said:

… Any drug which halts cognitive decline is potentially exciting because it has the ability to radically improve quality of life.

But Dr Simon Ridley of Alzheimer’s Research UK, said:

… This is a short study with a small number of participants. It is unclear if the (improvement) could be due to the control of blood pressure, a different effect of the drugs or another factor.

Among the most widely used ACE inhibitors are perindopril (also known as Coversyl), ramipril (Tritace), captopril (Capoten), trandolapril (Gopten), fosinopril (Staril), lisinopril (Zestril and prinivil).

They work by stopping the body from creating the hormone angiotensin II. This has a variety of effects but essentially relaxes blood vessels and helps reduce the amount of water re-absorbed by the kidneys – helping to decrease blood pressure.

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Medical, Research

Dementia risk raised after general anaesthetic for over 65s…

According to a study, having a general anaesthetic in later life could raise the risk of developing dementia by a third.

Brain changes caused by the anaesthetic could lead to Alzheimer’s within a few years in some patients, warn researchers.

It has long been known that having a general anaesthetic may result in poor brain functioning straight after an operation, especially in the elderly.

In most cases the side-effect is temporary, although many relatives complain their loved ones were ‘never quite the same’ after a major operation.

There has already been debate whether there is a link with dementia in the long term. Last year research on mice suggested cognitive function could be impaired in ways similar to changes caused by Alzheimer’s.

The latest study, though, found a 35 per cent higher risk of dementia in older people having surgery under general anaesthetic compared to local anaesthetic.

Extra cases of dementia emerged among patients up to eight years later, according to the study by the French Institute of Health and Medical Research and the University of Bordeaux.

Scientists in the UK say there is rarely an alternative to general anaesthetic if older patients need major surgery, but they do accept that more research could help identify those at risk.

Researchers’ analysed medical data of French people aged 65 and over living in three cities. They were interviewed at the start of the study and subsequently two, four, seven and ten years after.

Each examination included a complete assessment of cognitive functioning and systematic screening for dementia.

After two years, researchers started asking 7,008 participants whether they had undergone a general or local anaesthetic since the last follow-up. The data was adjusted to take account of factors such as socioeconomic status and other medical conditions which might raise the risk of dementia.

Altogether 19 per cent had undergone a general anaesthetic and 14 per cent had been treated under a local anaesthetic.

A total of 632 people – nine per cent – developed dementia over the eight subsequent years of the study, most of whom were diagnosed with Alzheimer’s.

The research was presented on 31 May, 2013, at Euroanaesthesia, the annual congress of the European Society of Anaesthesiology in Barcelona.

The researchers said the change in the brain that causes cognitive dysfunction after major surgery is the same as the one that causes dementia – when clumps of a protein stick to brain cells, affecting memory, mood and behaviour.

Several studies have suggested that some anaesthetic drugs could promote inflammation of brain tissue in a way that is characteristic of dementia.

Another theory is that insufficient oxygen to the brain may have an effect in vulnerable patients.

Alzheimer’s Research UK, a charity, said that we need to await the full peer-reviewed publication before fully interpreting the results.

Research into the impact of anaesthetics on dementia is challenging. Dementia is caused by several brain diseases, many of which arise from a complex mix of genetic and environmental factors.

Understanding these risk factors is vital, but research into dementia remains poorly funded compared to other diseases. We need to see sustained funding to unravel the full complexity of a condition that is often described as ‘devastating’.

Dementia Signs

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