(Reuters)
Updated: 2007-08-28 10:27

WASHINGTON -- Statin drugs may help prevent the brain damage that leads to Alzheimer's disease, US researchers reported on Monday.

Their study, published in the journal Neurology, bolsters a growing body of research that suggests the popular cholesterol-lowering drugs may reduce the risk of Alzheimer's.

Most studies have simply compared people who take statin drugs to those who do not, and track the rate of Alzheimer's.

"But our study is the first to compare the brains of people who had received statins with those who had not," said Dr. Gail Ge Li of the University of Washington School of Medicine in Seattle, who worked on the study.

Li and colleagues examined the brains of 110 people aged 65 to 79 who had donated their brains for research after they died as part of a study when they were still living.

The researchers looked at the brains for evidence of the plaques and tangles that characterize Alzheimer's, an incurable and progressive brain disease that is the leading cause of dementia.

They found significantly fewer tangles in the brains of people who had taken statins than in those who had not.

"These results are exciting, novel, and have important implications for prevention strategies," said Dr. Eric Larson, who helped direct the study.

"But they need to be confirmed, because (ours) is not a randomized controlled trial."

Such a trial would be difficult to conduct. It would require randomly assigning people to either take statins or not, watching to see who developed Alzheimer's, and looking at their brains after they died.

Statin drugs lower cholesterol and may also reduce inflammation in the body. The causes of Alzheimer's are not fully understood, but they are closely linked with cholesterol and also inflammation.

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

"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," Larson added in a statement.

Statins -- which include Pfizer Inc's $10 billion-a-year Lipitor, Bristol-Myers Squibb Co's Pravachol and Merck and Co Inc's Zocor -- are the world's best-selling drugs, taken by millions to reduce the risk of heart attack.