The Alzheimer's Society, together with the Cochrane Collaboration, has published the largest comprehensive review on the use of Ginkgo biloba for the treatment of dementia. This new research provides promising evidence that taking Ginkgo biloba can improve memory and overall function for people with dementia.
The systematic review published in the, 21 October 2002 issue of The Cochrane Library has identified 33 previous clinical trials of Ginkgo, dating back to 1976, and showed strong evidence Ginkgo helps improve cognition and function without the risk of excess side effects.
Ginkgo biloba, has long been used in China as a traditional medicine for various disorders of health, and a standardized extract is widely prescribed in Germany and France to help treat a variety of memory and concentration problems, confusion, depression, anxiety, dizziness, tinnitus and headache. Researchers believe several components of Ginkgo extract promote increased blood supply in the body by dilating blood vessels and reducing blood viscosity. It also modifies neurotransmitter systems, and acts as an antioxidant. According to Dr. James Warner, senior lecturer and consultant in Old Age Psychiatry at Imperial College London, these medicinal effects “suggest that Ginkgo might slow down a degenerative process.”
The review revealed Ginkgo, at dose levels of 200mg per day, showed significant benefits compared to placebo in a study period of 12 weeks. Fifty-four of 63 subjects showed improvement on the CGI scale measuring clinical global improvement. At 24 weeks, 57 of 79 subjects showed improvement at doses greater than 200mg per day. In addition, Ginkgo showed benefits in Activities of Daily Living and cognitive function in doses less than 200mg a day compared to placebo.
The researchers also found that Ginkgo is safe with no excess side effects when taken at recommended dosages, as they reported no significant differences between Ginkgo and placebo in the proportion of participants experiencing adverse events. They concluded the study stating:
“Ginkgo biloba appears to be safe in use with no excessive side effects compared with a placebo. Many of the early trials used unsatisfactory methods, were small, and we cannot exclude publication bias. But overall there is promising evidence of improvement in cognition and function associated with Ginkgo. Our view is that there is need for a large trial using modern methodology to provide robust estimates of the size and mechanism of the treatment effects.”
According to Dr. Mike Clarke of the Cochrane Collaboration, reviews, such as this bring together all the relevant evidence, to help make well-informed decisions about health care. This review helps to identify the types of research that are now needed to find the best treatments for people with dementia.
These findings have provided the green light for a major new clinical trial of Ginkgo in people with early dementia who are looked after by their general practitioner. The new study will recruit 400 people with dementia, following them over a period of six months while they receive treatment either with Ginkgo or a placebo.