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Onderzoek naar Ginkgo als behandeling bij
dementie.*
In Londen is een onderzoek
gestart naar de effectiviteit van Ginkgo bij de behandeling van beginnende
dementie. Van Ginkgo is bekend dat
het bloedvaten verwijdt en het bloed dunner maakt, waardoor er minder kans op
bloedstollingen zijn en antioxidant werking heeft bij het beschermen van
zenuwcellen. Hierdoor zou Ginkgo een goede behandelmethode kunnen zijn voor
beginnende dementie. Met dit onderzoek hoopt men dit te kunnen bewijzen waardoor
dan een veilig en goedkoop middel in tegenstelling tot de nu toegepaste
medicijnen beschikbaar is.
Researchers in London are to
explore the effectiveness of gingko, a complementary medicine traditionally used
to treat circulatory problems, as a treatment for early dementia.
The study of 250 patients aged
over 55 will seek to find out whether GPs can help patients by prescribing the
supplement to those with memory loss, one of the early symptoms of dementia.
It will be the first to test
gingko as a treatment for those who are still living in the community and are
being treated by their GP. Previous trials have concentrated on patients
receiving hospital care, where the condition is often more advanced.
"We believe gingko may
prove more effective if prescribed in a community setting, where patients'
symptoms are usually less severe," says Dr James Warner, a psychiatrist
from Imperial College London and St Mary's Hospital, who is leading the study.
"This trial will help us to find out whether with gingko it's a case of
'the sooner the better', for patients who may benefit from taking it."
Gingko is believed to cause
blood vessels to dilate, improving blood flow to the brain, and to thin the
blood, making it less likely to clot. Gingko may also have antioxidant effects,
protecting nerve cells against biological 'rusting'.
"All of these effects
would suggest that gingko might slow down a degenerative process such as
dementia," says Dr Warner.
It is estimated that 700,000
people in the United Kingdom are affected by the condition, 60 per cent of whom
are diagnosed with Alzheimer's disease. Patients might occasionally
misunderstand who or where they are, forget people's names or how to get home.
Gingko could provide a cheaper
alternative to conventional medicines, with fewer of the potential side effects
such as nausea, loss of appetite, tiredness and diarrhoea. A quality gingko
extract taken from the Gingko biloba tree costs around £200 for a year's
supply. It is currently available over the counter in the UK, most European
countries and the United States.
Conventional medicines for
memory loss are based upon a class of drugs known as cholinesterase inhibitors,
which cost around £1,000 a year, and prescription of these drugs is restricted.
Some patients also benefit from therapies such as music therapy, aromatherapy
and reminiscence therapy, which keep the environment stimulating and encourage
the use of the brain.
Participants on the
double-blind trial will continue to take their conventional medicines for
age-associated memory loss. For six months they will be given 60mg of gingko
extract or a placebo twice daily. Participants will also receive up to three
visits of one and a half hours where researchers will examine each individual's
cognitive functioning, their memory, quality of life and behaviour.
Robert McCarney, research
associate on the study adds "We are now recruiting individuals living in or
around London and the home counties, aged over 55 and whom their GP suspects may
have dementia. Anyone interested in finding out more about the study should
telephone 020 7886 7697".
For general information
relating to age-associated memory loss or Alzheimer's disease, contact The
Alzheimer's Society helpline on 0845 300 0336.
The study is being carried out
by Imperial College London in collaboration with the London School of Hygiene
and Tropical Medicine, the Royal London Homeopathic Hospital and University
College London. The Alzheimer's Society is funding the research.
Gingko facts
* Fossilised remains of the
ancient tree have been found dating back 200 million years.
* It has been used in
traditional Chinese medicine for at least 5,000 years.
* In Germany, gingko is of the
top 10 prescription medicines for the treatment of circulatory problems. Germans
spent 280 million dollars on gingko in 1993.
* Four gingko trees survived
the atomic bomb in Hiroshima in August 1945, leading local people to name the
tree the 'bearer of hope'.
* The gingko tree can grow up to forty metres tall and can achieve a spread of nine metres.(aug. 2004)