Mon Apr 16, 2007
NEW YORK (Reuters Health) – A study conducted in France provides preliminary evidence that older people who take Ginkgo biloba may be extending their lives, but are not reducing their risk of dementia
Among 3,534 men and women 65 and older, those who used the herb were 24 percent less likely to die over a 13-year period than their peers who didn’t take ginkgo, Dr. Jean-Francois Dartigues at the University of Bordeaux and colleagues found.
Dartigues and his team note that Ginkgo biloba extract has been sold in France for more than three decades to enhance memory. To date, they add, most studies have focused on whether the herb prevents dementia, but because older people have a much greater risk of dying, dementia-free survival should also be included as an outcome.
The researchers looked at the effect of several different dementia prevention treatments on the study participants, collecting data when the study began, in 1988, and every 2 years thereafter.
At the start of the study, 6.4 percent of the participants were taking Ginkgo biloba extract, while 25.1 percent were taking some other type of memory enhancing treatment. After 13 years, 53.1 percent had died and 17.6 percent had developed dementia.
About half of people who took no memory enhancing treatment died, compared with 46.7 percent of those taking Gingko biloba and 62.1 percent of those taking some other type of memory-boosting drug. Among those on Gingko biloba, 21.4 percent developed dementia, compared with 22.4 percent of those on other memory treatments and 15.5 percent of those who were not taking memory enhancers.
The researchers found that while the effect of the herb on mortality risk remained significant, it had no effect on the likelihood of developing dementia. People taking other memory treatments were actually at increased risk of dementia, but did not have a greater risk of dying.
These results should be interpreted carefully, the researchers note, because people taking Gingko or other memory enhancers at the beginning of the study may have been at greater risk of dementia than those who weren’t taking such treatment.
“Nevertheless, it cannot be excluded that Ginkgo biloba may have a beneficial effect on survival in the elderly population,” they write.
The results must be confirmed in randomized, prospective clinical trials in which people taking the extract are compared to those who aren’t, the researchers add. They point out that there are currently over 5,800 people taking part in such studies in the US and Europe, with results expected in 2010.
SOURCE: Journal of the American Geriatrics Society, March 2007.