How statins can help to protect from Alzheimer's

An analysis of brain tissue has provided the first direct evidence that statins - taken to prevent heart disease and strokes - can also ward off dementia and memory loss.

The findings were welcomed by Alzheimer's campaign groups, who say there is growing evidence the common and relatively cheap drugs reduce the risk of the degenerative disease.

But they warned that it was too soon for people to begin taking statins purely as a means of preventing Alzheimer's. More research was needed.

The use of statins has shot up in the last few years, driven by the Government's aim of cutting heart disease by 40 per cent by 2010.

Family doctors are being offered financial incentives to give them to as many high-risk patients as possible.

The Alzheimer's findings come from a study of 110 brains - donated for medical research - at the University of Washington School of Medicine in Seattle.

A team led by Dr Gail Li examined them for changes linked to Alzheimer's - the creation of "plaques" and "tangles" made from the protein beta amyloid.

These changes appear in the brain long before any symptoms of dementia develop.

Eventually, they damage enough brain cells to trigger confusion, memory loss and eventually death.

The researchers found far fewer tangles in the brains of people who had taken statins, compared to those who had not.

The findings were true even after age, sex and the history of strokes were taken into account.

It is the first study to compare the brains of people who took statins with those who did not.

"These results are exciting, novel and have important implications for prevention strategies," said Dr Eric Larson, a co-author of the study which is published today in the American journal Neurology.

He stressed that further studies were needed to confirm the findings but said the research had been "more rigorous" than past studies.

Professor Clive Ballard, director of research at the Alzheimer's Society, said: "This is an exciting piece of research. These studies are very complicated to interpret as there are a number of other factors that can influence changes in the brain.

"But the evidence is building that statins may reduce the risk of Alzheimer's disease.

"This research highlights the need for a wider controlled study."

Statins work by blocking the action of a chemical in the liver which is needed to make the £bad" form of cholesterol, LDL.

Reducing levels of bad cholesterol keeps blood vessels unclogged.

The US researchers are not sure how statins also prevent the build-up of protein tangles in the brain.

They suspect that a healthy flow of blood is a key factor.

Around 700,000 people suffer from dementia in the UK. Two thirds have Alzheimer's disease.

Studies on statins and Alzheimer's have already begun in the US, but the Seattle researchers warn that not everyone may benefit.

"People with Alzheimer's are diverse," said Dr Li.

"Statins are probably more likely to help prevent the disease in certain kinds of people than others.

"Someday we may be able to know more precisely which individuals will benefit from which types of statins for preventing the changes of Alzheimer's disease."

Five years ago a study at Boston University found that statins may cut the risk of Alzheimer's by as much as 79 per cent, even in people with a family history of the disease.

Some small-scale studies have found an apparent link between statins and cancer and Parkinson's disease.

However, other studies suggest that the drugs can ease the pain of rheumatoid arthritis.