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The Ginkgo Evaluation of Memory Study (GEMS) is a primary prevention trial of EGb 761 120 mg twice daily versus placebo. The primary study outcome was incident dementia, with secondary outcomes of cardiovascular disease/mortality, physical function, and cognitive change/progression as related to study drug.

The study formulation and dose of Ginkgo biloba was not effective in reducing incident dementia.

Study Participants

Between October 2000 and May 2002, 3069 non-demented subjects ages >=75 years were screened and randomized to drug or placebo at four field centers; University of Pittsburgh, Pittsburgh PA, Wake Forest University, Winston-Salem and Greensboro NC, University of California Davis, Sacramento CA, and Johns Hopkins University, Hagerstown MD. Subjects were community dwelling volunteers. Subjects underwent detailed baseline and annual cognitive testing, and those with abnormal testing underwent a neurological exam and MRI. Subjects with an incident dementia diagnosis discontinued participation and were referred for treatment. Cognitive status was known for 93.6% of all trial participants. Retention in the trial was very high (195 withdrawals, 379 deaths).

Available Data

Data collection was longitudinal until subjects reached the incident dementia endpoint, or the end of the trial. Median follow up from entry to final visit was 6.1 years. The detailed cognitive testing battery was administered at baseline and then annually beginning in 2003, with semi-annual administration of the 3MSE and CDR. A minimal dataset is available through NCRAD to approved users. The full dataset is available upon request from the GEMS Executive Committee.

Available Biospecimens

Genomic DNA, Plasma, Serum