First, the details.
- 3069 elderly community-dwelling participants were assigned to a treatment group for about 6 years.
- Twice-daily dose of 120 mg extract of Ginkgo biloba
- Identical-appearing placebo
- Rates of change over time in the Modified Mini-Mental State Examination (3MSE), in the cognitive subscale of the Alzheimer Disease Assessment Scale (ADAS-Cog), and in memory, attention, visual-spatial construction, language, and executive functions, were recorded.
- Neither the patients nor researchers knew the treatment given — double blind.
And, the results.
- There were no differences in annual rates of decline of memory, attention, visual perception of spatial relationships among objects, language, and executive functions.
- Age, sex, race, education, APOE e4 gene, or baseline mild cognitive impairment had no effect on the results.
- The APOE e4 gene may be associated with an earlier onset of memory loss and other symptoms.
The bottom line?
This same group of researchers reported last year that G. biloba doesnâ€™t reduce the incidence of dementia or Alzheimerâ€™s disease in elderly individuals.
Now, they tell us that G biloba doesnâ€™t affect the rate of cognitive (reasoning) decline in adults with normal cognition or with mild cognitive impairment.â€
Others have reported conflicting results. However, the work by the GEM researchers stands out because the National Center for Complementary and Alternative Medicine (NCCAM) and the National Institute on Aging of the National Institutes of Health (NIH) sponsored both GEM studies and insisted that the G. biloba used meet â€œspecific standards of exact chemical content and consistency.â€
In other words, the lack of effect in these studies canâ€™t be blamed on poor manufacturing standards of G. biloba tablets.
The only remaining question is whether the dose used was adequate to achieve a response.
12/30/09 19:45 JRGinkgo: The biggest loser in 2009