Can statin drugs reduce dementia?

A new study has shown that certain anti-cholesterol drugs called statins can cut chances of developing dementia by more than fifty percent. Statins such as Lipitor and Zocor are the world’s best-selling drugs, taken by millions to reduce the risk of heart attack by reducing cholesterol.

Earlier research on statins and dementia had delivered mixed results. But the results of this new study make a much stronger case for the drugs’ effectiveness. Researchers reviewed the records of 4.5 million patients treated at VA hospitals from 2002 to 2005. Simvastatin (Zocor) was found to offer the greatest protection against dementia. Patients who took it for at least seven months were 54 percent less likely to develop dementia. Atorvastatin (Lipitor) reduced dementia risk by 9 percent, while a third drug, lovastatin (Mevacor), offered no advantage.

Another study, published in the August 28, 2007, issue of Neurology, demonstrated an association between statin use and lower incidence of the changes in the brain associated with Alzheimer’s disease. University of Washington researchers and colleagues examined the brains of 110 people aged 65 to 79 after they died. The brain autopsies showed that participants who had taken statins were 80% less likely to have brain changes typical of Alzheimer’s disease than those who hadn’t. This study was the first to actually compare the brains of people who had received statins with those who had not. Although these results appear promising, more studies are needed to confirm these findings.

“These results are exciting, novel, and have important implications for prevention strategies,” said Dr. Eric Larson, who helped direct the brain study. “But they need to be confirmed, because (ours) was not a randomized controlled trial. Fortunately, there are randomized trials now underway, so we may have more definitive results relatively soon. In the meantime, our team is not making any recommendation regarding treatment based on this study.”

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 with inflammation. 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,” said Larson.

Fortunately there are things people can do now to reduce their risk of dementia. Regular exercise is associated with a delay in the onset of dementia and Alzheimer’s disease. People who exercised three or more times a week were found to have a 30 to 40 percent lower risk for developing dementia. There’s also growing evidence that other lifestyle factors, such as being engaged in social networks and participating in mentally stimulating leisure-time activities, may delay onset of Alzheimer’s and the general decline that occurs in old age.

The bottom line: Stay active physically, socially, and mentally. And if you have a chronic condition like high blood pressure, high cholesterol, or heart disease, be an actively involved patient. Learn about your condition and take care of it, following the advice of your doctor.

For more information on dementia and Alzheimer’s disease, visit the National Institute on Aging at www.nia.nih.gov.