– April 21, 2003 – Cholesterol-lowering medications known as statins also
play an important role in reducing levels of a strong predictor of Alzheimer's
disease, according to a new study from UT Southwestern Medical Center at
In today's issue of the Archives of Neurology, UT Southwestern researchers
report that participants who took statins lowered their brain cholesterol
levels by 21.4 percent. Brain cholesterol is involved in the formation of
amyloid plaques, one of the hallmarks of Alzheimer's disease. Amyloid plaques
are waxy buildups that harm brain cells.
"This class of drugs may be potentially beneficial in the treatment of
Alzheimer's disease," said Dr. Gloria Vega, professor of clinical nutrition
and the study's lead author.
"If we limit cholesterol synthesis in the brain, we may be able to decrease
the production of amyloid plaques. The findings from this research provide
information about the safety and efficacy of a reasonable dose of a statin
on the reduction of brain cholesterol."
There is currently no cure for Alzheimer's disease, which affects four
million Americans. But this study, UT Southwestern researchers said, suggests
that reducing cholesterol in the brain also can reduce plaque formation,
thereby potentially reducing the severity of Alzheimer's disease.
"We've shown that you can take people with Alzheimer's disease, with normal
cholesterol levels, and reduce the amount of cholesterol that their brain
produces without any adverse side effects," said Dr. Myron Weiner, vice chairman
of clinical services in psychiatry and a co-author of the study. The study
included 44 Alzheimer's patients, none with cardiovascular disease. The study
participants were randomly assigned to receive either 40 milligrams per day
of lovastatin, simvastatin or pravastatin, or one gram per day of extended-release
niacin (another cholesterol-lowering medication) for a six-week period.
Unlike dietary cholesterol, which is transported to the liver and excreted
through the bile, the brain gets rid of cholesterol by first converting it
into 24S-hydroxycholesterol, which is elevated in individuals with Alzheimer's
disease. The researchers measured, through blood samples, the amount of 24S-hydroxycholesterol
to determine how much cholesterol was expelled from the brain.
All three statins reduced levels of 24S-hydroxycholesterol by at least
20 percent, while 24S-hydroxycholesterol levels dropped by 10 percent with
"It would be interesting to determine whether a combination of a statin
and extended-release niacin has an additive effect on levels of 24S-hydroxycholesterol,"
Weiner is the lead study investigator at UT Southwestern for the Alzheimer's
Disease Cooperative Study, a National Institute on Aging multicenter study,
which is evaluating whether statins play a role in slowing the progression
of Alzheimer's. Results from that study are expected in the next two years.
"Now that we've shown that statins safely and effectively reduce levels
of brain cholesterol, we are studying what statins do cognitively for people
with Alzheimer's," he said.
Other researchers involved in the study included Dr. Anne Lipton, assistant
professor of neurology and psychiatry; Carol Moore, research assistant in
psychiatry; Doris Svetlik, a nurse administrator in psychiatry; and researchers
with the Department of Clinical Pharmacology at the University of Bonn Medical
Center in Germany.
The study was funded in part by the Wallace, Barbara and Kelly King Charitable
Foundation Trust, the Merit Review Grant of the Dallas Veterans Affairs Medical
Center, the Moss Heart Foundation and the National Institute on Aging.
This story has been adapted from a news release issued for journalists and
other members of the public. If you wish to quote any part of this story,
please credit University Of Texas Southwestern Medical Center At Dallas as the original source. You may also wish to include the following link in any citation: