Gingko beschermt niet tegen dementie
The results from the GEM Study did not show that G biloba is effective in preventing or delaying the onset of all-cause dementia in participants older than 75 years. G biloba also had no effect on the risk for developing AD in this age group.
The higher rate of AD in individuals with pre-existing CVD and assigned to G biloba is puzzling and should be viewed with caution given the lack of evidence from published basic science research supporting a potential mechanism for G biloba increasing Alzheimer dementia risk in individuals with CVD.
Similarly, the very small number of purely vascular dementia cases identified in the GEM Study (n = 24) and the lack of effect on the incidence of myocardial infarction or stroke make any conclusion about the relationship between G biloba and prevention of vascular dementia imprudent.
Also, although no firm conclusion can be drawn from the higher number of hemorrhagic strokes in the G biloba group, this finding should be explored in future studies.
In een commentaar werd gesteld dat er zo veel negatieve studies zijn, en negatieve of onduidelijke meta-analyses, dat de kans dat Gingko iets zinvols doet bij dementie heel laag is.
The GEM study adds to the substantial body of evidence that G biloba extract as it is generally used does not prevent dementia in individuals with or without cognitive impairment and is not effective for Alzheimer disease. With respect to preventing stroke or minimizing the damaging sequelae from stroke, the slight evidence is vague and contradictory. Users of this extract should not expect it to be helpful.
Moreover, the potential adverse effects of G biloba extract illustrate why it is untenable to recommend a drug or nutraceutical in the absence of efficacy evidence simply because it could possibly help and initially appears harmless.
Gingko heeft dus geen groen licht, maar oranje, het lijkt er zelfs op dat het niet zinvol is en zinloos om dit preparaat te gebruiken.
Bron: Ginkgo biloba for Prevention of DementiaA Randomized Controlled TrialSteven T. DeKosky, MD; Jeff D. Williamson, MD, MHS; Annette L. Fitzpatrick, PhD; Richard A. Kronmal, PhD; Diane G. Ives, MPH; Judith A. Saxton, MD; Oscar L. Lopez, MD; Gregory Burke, MD; Michelle C. Carlson, PhD; Linda P. Fried, MD, MPH; Lewis H. Kuller, MD, DrPH; John A. Robbins, MD, MHS; Russell P. Tracy, PhD; Nancy F. Woolard; Leslie Dunn, MPH; Beth E. Snitz, PhD; Richard L. Nahin, PhD, MPH; Curt D. Furberg, MD, PhD; for the Ginkgo Evaluation of Memory (GEM) Study Investigators JAMA. 2008;300(19):2253-2262.
Editorial: Ginkgo biloba Extract and Preventing Alzheimer Disease. Lon S. Schneider, MD JAMA. 2008;300(19):2306-2308.