New study will look at whether herb can delay, prevent Alzheimer's disease
　　A four-year study to determine whether ginkgo biloba delays or prevents Alzheimer's disease is under way at Oregon Health Sciences University.
　　"This is the first study we know of that's looking at ginkgo's ability to help prevent or delay the onset of dementia symptoms," says Tracy Zitzelberger, research assistant, Dementia Prevention Study, neurology department, at the university.

Ginkgo biloba is used around the world by alternative and complementary health providers, who believe it improves a person's memory. It's a huge market: Americans spent $240 million on ginkgo biloba in 1997 alone.

But there isn't much scientific evidence to confirm the benefits of this plant extract. Most of the studies on it have been done without rigorous scientific standards

The Oregon study, which started last August, will focus on people 85 and older who currently have no symptoms of dementia.

"Because they are at the highest risk to experience dementia, it does make them the ideal population to do this kind of research with," says Zitzelberger, who notes that half the population of people over 85 have some form of dementia.

There are 51 people enrolled in the study, but researchers would like to recruit 200 people.

Half of the subjects will receive ginkgo biloba while the others receive a placebo. Each volunteer will receive regular checkups. Written and verbal tests will be used to determine if there has been any significant cognitive decline during the span of the study. MRI testing will be used to detect any changes in brain structure.

Zitzelberger says this study is unique in that it's looking at ginkgo biloba's ability to delay or prevent dementia symptoms, while other studies have focused on whether it could lessen symptoms in people already experiencing dementia.

While ginkgo biloba has been used for centuries in Eastern cultures, it hasn't been the focus of much research. One reason for that is because it's not a pharmaceutical that can be patented, so drug companies have no incentive to investigate it.

This study is funded by the National Center for Complementary and Alternative Medicine at the National Institutes of Health (NIH).

Zitzelberger says ginkgo does show great promise, and it's vital to determine just how effective it may be in countering Alzheimer's, which is devastating to patients and their families.

"It's becoming an increasing problem. As we're living longer, we're seeing more people developing it, and we don't yet understand fully how it works, how to treat it, or how we might prevent it. It's a major public health issue," she says.

Approximately 4 million Americans have Alzheimer's. It affects one in 10 people 65 and older.

There does seem to be some indication that ginkgo is beneficial, says William Thies, vice president of medical and scientific affairs at the Alzheimer's Association.

"You can criticize the methodology in most of the trials that have been done up until now, but this trial and others will feature rigorous methodology, and are really going to answer these questions," Thies says.

"In an environment where we have a limited number of therapeutic options for Alzheimer's disease, nothing would please the association more than to be able to say, 'Hey, here's another thing that you could do to help you with this terrible problem,' " Thies says.

　　From HealthScout