June 3, 2008
Those with high cholesterol in their early 40s are more likely to develop Alzheimer's disease than those with low cholesterol, according to a new report of nearly 10,000 men and women living in northern California. High cholesterol has long been linked to heart attacks and strokes. These new findings emphasize that maintaining healthy cholesterol levels may also be good for the brain.
"Our findings show it would be best for both physicians and patients to attack high cholesterol levels in their 40s to reduce the risk of dementia," said study author Alina Solomon, M.D., with the University of Kuopio in Finland.
Study participants underwent health evaluations between 1964 and 1973, when they were between the ages of 40 and 45. All remained with the same health plan through 1994. From 1994 to 2007, researchers obtained the participants' most recent medical records. They found that 504 people had been diagnosed with Alzheimer's disease. Another 162 had vascular dementia, another serious form of memory loss caused by poor blood flow to the brain.
The researchers found that people with total cholesterol levels between 249 and 500 milligrams were one-and-a-half times more likely to develop Alzheimer's disease than those with cholesterol levels of less than 198 milligrams. People with total cholesterol levels of 221 to 248 milligrams were more than one-and-a-quarter times more likely to develop Alzheimer's disease. A total cholesterol level below 200 is generally considered healthy.
"High mid-life cholesterol increased the risk of Alzheimer's disease regardless of mid-life diabetes, high blood pressure, obesity, smoking and late-life stroke," said Dr. Solomon. The research was presented April 16 at the American Academy of Neurology 60th Anniversary Annual Meeting in Chicago.
This is an interesting study, but it is not clear whether high cholesterol during midlife sets in motion a disease process that leads to dementia, or whether those with high midlife cholesterol tend to maintain high cholesterol levels that contribute to Alzheimer's risk later on.
Earlier research has also linked high cholesterol to an increased risk for Alzheimer's disease and other forms of dementia. However, it is uncertain whether giving the popular cholesterol-lowering statin drugs may help to ward off memory problems in old age.
Some studies suggest that statins may help, while others show no proven benefits. Additional research is needed to resolve this issue.
Still, experts agree that keeping cholesterol at a healthy level is good for the heart -- and the brain. A diet low in animal fats and other saturated fats, but high in fiber, can help to keep cholesterol levels down. Regular exercise, and keeping weight down, can also help. In addition, moderate consumption of red wine or alcohol, just one or two glasses a day, may help to keep cholesterol in check.
Presented at the American Academy of Neurology 60th Anniversary Annual Meeting in Chicago, April 12 to 19, 2008.