Researchers in the United States say they believe cholesterol-lowering drugs may reduce the risk of Alzheimer's.
A new study by researchers at the University of Washington School of Medicine in Seattle, has found that statin drugs may help prevent the brain damage that leads to Alzheimer's disease.
Their research supports other studies which have also found that the poor blood flow and vascular changes in the brain, which statins may help to prevent, may reduce the risk of Alzheimer's.
The large-scale study was conducted at Boston University from 2002, and it found that the drugs possibly reduce the risk of Alzheimer's by as much as 79 per cent, even in people thought to be genetically susceptible to the disease and after allowing for variables such as age, gender and previous health issues.
This study differs say the research team as it is the first to compare the brains of people who had received statins with those who had not; other studies simply compared people who take statin drugs to those who do not, and tracked the rate of Alzheimer's.
According to Dr. Gail Ge Li, one of the authors of the study, when the team examined the brains of 110 people aged 65 to 79 looking for evidence of the plaques and tangles that characterize Alzheimer's, they found significantly fewer in the brains of people who had taken statins than in those who had not.
The subjects had donated their brains for research after they died as part of the study.
Alzheimer's is an incurable and progressive brain disease that is the leading cause of dementia.
Dr. Eric Larson, co-author of the study says the results are exciting, novel and have important implications for prevention strategies but will need to be confirmed by a randomized controlled trial.
This might present problems as it would entail randomly assigning people to either take statins or not and then waiting to see who developed Alzheimer's, and then examining their brains after death.
Experts suggest that while statin drugs lower cholesterol they may also reduce inflammation in the body and while the exact causes of Alzheimer's are unclear it is suspected the disease is linked to cholesterol and inflammation.
The researchers say statins are probably more likely to help prevent the disease in certain people than others and someday it may be possible to predict which individuals will benefit from statins in the prevention of Alzheimer's disease.
Statins are the world's best-selling drugs and are taken by millions to reduce the risk of heart attack, they include Lipitor, Pravachol and Zocor.
The study is published in the journal Neurology.