New Study Strengthens Cholesterol / Alzheimer's Link

Alzheimer's Association
Wednesday, 22 January 2003

A European study reported in the January issue of the Archives of Neurology provides compelling evidence of the role cholesterol metabolism may play in Alzheimer's disease according to the Alzheimer's Association.

"These findings provide fascinating clinical and pathological data that add to earlier studies linking cholesterol-lowering drugs called statins with a reduced risk of Alzheimer's disease," said Bill Thies, the association's vice president, medical and scientific affairs.

"We are eagerly awaiting further information about the possible value of cholesterol management in the prevention or treatment of Alzheimer's disease,"Thies said.

A host of epidemiological studies suggesting that a range of lifestyle elements including diet and nutrition, cholesterol levels, body weight, exercise, blood pressure and hypertension, reduce the risk of developing Alzheimer's were reported last summer at the 8th International Conference on Alzheimer's Disease and Related Disorders sponsored by the Alzheimer's Association.

This new study links a common variant form of the gene for an enzyme involved in the brain's cholesterol metabolism to Alzheimer's. The CYP46 enzyme modifies cholesterol, making it more soluble and better able to facilitate the transport of excess cholesterol out of the brain. The CYP46-TT variant form of the gene is found in approximately 40 percent of people.

The researchers found the TT variation of the CYP46 gene associated with increased levels of key Alzheimer proteins in brain tissue samples as well as in the cerebrospinal fluid of living study participants. The authors' genetic association analysis of two separate populations showed increased risk of Alzheimer's in people with the CYP46-TT variant.

The researchers further found a strong combined effect between the CYP46-TT variant and APOE-e4, the first known late-onset Alzheimer risk gene. APOE-e4 is one variation of the gene for apolipoprotein E, a protein that transports cholesterol in the brain. Individuals with both genes had the strongest elevated risk for Alzheimer's disease of any group in the study.

The Alzheimer's Association is the premier source of information and support for the 4 million Americans with Alzheimer's. The largest private funder of Alzheimer research in the United States, the Association has committed $136 million toward research into the disease. In 1999 the Alzheimer's Association awarded Dr. Papassotiropoulos, lead author of the study, a research grant for his ongoing investigation of Alzheimer genetics.

For more information, or to contact Alzheimer's Association, see their website at: www.alz.org