Study Finds Potential New Cause Of Mental Decline In Old Age
Doctors have found important new evidence to explain why mental function
becomes less efficient with ageing. In the first study of its type in the
world, a team at the University of Edinburgh found that worse mental
function is linked with abnormally enlarged channels around blood vessels in
the brain. The report, published in the Journal of Neurology, Neurosurgery
and Psychiatry, will help doctors to better understand the causes of
dementia.

Dementia and milder forms of loss of mental ability affects millions of
older people every year, but the causes are unclear. Previous research using
brain scanning has shown that brain shrinkage and changes in the brain's
white matter 'wiring', are associated with mental function slowing down in
old age. This research adds a new way in which damage to the brain may
result in dementia and other mental loss in older people.

The abnormal channels are known as enlarged perivascular spaces. Rare in
young, healthy adults, they are very commonly seen in the brain scans of
older people, and in conditions such as diabetes, Parkinson's disease, and
high blood pressure. Researchers have long noted these abnormalities, but
until now there has been no research on any links with mental function in
old age. The enlarged perivascular spaces might be an indicator of overall
brain shrinkage, or they might reflect specific damage to brain tissue
around blood vessels.

Dr. Alasdair MacLullich, of the University's Geriatric Medicine Unit,
measured mental ability in100 healthy elderly male volunteers from the
Edinburgh area. Professor Joanna Wardlaw, from the Brain Imaging Research
Centre for Scotland, measured the extent of the enlarged perivascular spaces
in these men using a new and innovative method of analysis. The team, which
also included researchers from psychology and endocrinology, found that men
with more enlarged perivascular spaces had worse mental ability.

Dr. MacLullich commented: "These findings mean that we should certainly be
looking more closely at enlarged perivascular spaces as a cause of dementia
and other mental decline in old age. They raise the interesting
possibilities that there may be substances in the blood, such as cholesterol
or sugar levels, or even blood pressure itself, that may contribute to
memory decline as people become older. This puts a spotlight on blood
vessels, so we are now working to find out how these changes around the
brain's blood vessel supply arise."

Source= http://www.ed.ac.uk/news/mentaldecline.html