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PARIS : World Alzheimer's Day this Thursday marks the 100th anniversary of when a brain-destroying disorder that many might call the cruellest disease of all entered the medical books.
In a study in 1906 that broke new ground in knowledge about dementia, German doctor Alois Alzheimer presented the case history of a 51-year-old woman, Auguste D.
Five years earlier, Auguste D. had started to suffer memory loss. She developed problems with speaking, became confused, paranoid and agitated. By the time she died, she had become incontinent, bedridden and oblivious to her surroundings.
Carrying out an autopsy on his former patient, Alzheimer found Auguste D.'s brain had shrunk through loss of neurons and was clogged with fibrous tangles and plaques.
Alzheimer presented his findings at a conference in the university of Tuebingen in November 1906. But for the next eight decades, knowledge of the disease that bore his name stayed to a large degree unchanged.
Alzheimer's became a byword for dread of ageing - but also bafflement as to its cause, and despondency about how to treat it.
Today, though, the news about this darkest of diseases burns with a flame of hope.
Alzheimer's is being attacked on so many fronts that some researchers, while balking at talk of a cure, believe a treatment to slow or possibly stop its clinical advance is tantalisingly within reach.
"If you look at beta amyloid formation alone, there are three or four approaches and all can bear fruit within 10 years," said Bengt Winblad, a professor of geriatrics at Sweden's Karolinska Institute in Stockholm.
Beta amlyoid formation refers to the plaques of proteins that clump outside the brain cells. They are a hallmark of Alzheimer's, as are the tangles of so-called tau protein inside the neurons. It is still unclear, though, whether tau is a cause or an effect of Alzheimer's.
Two research areas that could yield a marketable drug "within three to five years" focus on interfering with the molecular cascade that allows the plaques to form and stick together, said Winblad.
"Even if there is no cure, if you delay progression or halt disease, that is something that the relatives of the patients 1/8with Alzheimer's 3/8 would be very happy with indeed," he said.
Another approach is to clear the brain of the plaque deposits. This could be achieved by an "active vaccine" in which part of the beta amyloid would be injected into the body in order to prime the immune system against it, or by injecting antibodies directly.
Much of this encouraging research has already left the lab and is undergoing early human trials, a long, costly three-phase approach to test a new molecule for safety and effectiveness.
In addition, more and more is known about telltale pre-stages of Alzheimer's and about conditions such as smoking, obesity, diabetes and high blood pressure that appear to contribute to it, while mental exercise and a diet rich in fruit and vegetables appear to have a protective effect. There is also an indication that some people may be genetically more susceptible to it than others.
A breakthrough is urgently needed when it comes to Alzheimer's.
Alzheimer's primarily shows up in people beyond their mid-60s. Thus, as more and more people around the world live longer, the disease is bound to progress.
According to a study published last December in the journal The Lancet, 24 million people today have dementia, and the figure will rise to 42 million by 2020 and 81 million by 2040.
China and South Asia will see a tripling of Alzheimer's patients by 2040, the study said. It did not break down the figures for the different forms of dementia; Alzheimer's is estimated elsewhere to be the cause in around half of dementia cases.
Compared with cancer and cardiovascular patients, Alzheimer's lags far behind in raw numbers and receives only a fraction of these diseases' research funds.
But it catches up when it comes to cost, both in terms of the financial burden to health system and the brutal toll exacted on families.
"We have to solve dementia crisis, otherwise the health care system in many countries will collapse," said Winblad. "We have to resolve how we shall handle dementia patients, with drugs or care, otherwise with the demographic changes, in 20 or 30 years they will be occupying every (hospital) bed that we have today."
Alzheimer's: A factfile
WHAT IS IT?
Alzheimer's disease is the commonest form of dementia, a degenerative disease of the brain that causes forgetfulness and disturbs thinking, emotions and behaviour.
HOW MANY PEOPLE HAVE IT?
Twenty-four million people today have dementia, a figure likely to rise to 42 million by 2020 and 81 million by 2040. Alzheimer's accounts for between 50 and 60 percent of all dementia cases. The direct and indirect annual costs of caring for people in the United States alone are put at at least 100 billion dollars annually.
WHAT HAPPENS?
Clumps of protein called amyloid plaques and tau tangles proliferate in the brain, especially the cortex and hippocampus, destroying brain cells and their connections. The onset of symptoms is gradual. Psychiatric, physical and neuro-imaging tests are needed to confirm diagnosis.
WHO IS AT RISK?
Alzheimer's most commonly appears after the age of 65 and the risk increases with ageing. The precise cause is unclear but genes, environment and lifestyle may all play a role. On average, people live eight years after diagnosis, but this can range from as little as three to as many as 20 years.
IS THERE A CURE?
No. If all goes well, the first drugs to slow or block the spread of Alzheimer's could be only a few years away. Present drugs have a temporary effect by inhibiting an enzyme that reduces acetylcholine, a vital chemical used in communication between brain cells.
OTHER TREATMENT:
Antidepressants, anti-anxiety drugs and tranquillisers can ease sleeplessness, agitation, wandering, anxiety and depression, thus making the patient more comfortable and easing the burden of caregivers. Psychological, art and music therapy are also commonly used to try to stimulate the brain of Alzheimer's patients.
Sources:
Alzheimer's Disease International (http://www.alz.co.uk/)
US National Institutes of Health (NIH) 2001-2 Alzheimer's Disease Progress Report; US National Institute of Ageing (http://www.nia.nih.gov/Alzheimers/Publications/adfact.htm)
The Lancet (issue of December 17 2005)
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