Ginkgo Biloba Prevention Trial in Older Individuals

Primary Outcome Measures:

• Number of Participants With Incident Dementia [ Time Frame: Brief neuropsychological testing every 6 months, detailed testing annually, average 6.1 years follow up ]
  All cause dementia based on DSM-IV criteria as determined by an expert panel of clinicians using an adjudication process. A full neuropsychological battery was administered annually, or at 6 month visit if there was a diagnosis of dementia or initiation of medication for dementia by private physician, or change in Modified Mini Mental State Exam (3MSE), Clinical Dementia Rating (CDR), or Alzheimer Disease Assessment Scale (ADAS-Cog). Decline on tests scores based on an algorithm resulted in a neurological exam and brain imaging. These data were used in the adjudication process.
  
  

Secondary Outcome Measures:

• Number of Participants With the Indicated Cardiovascular Disease or Mortality [ Time Frame: 6 months ]
  Myocardial infarction (MI), angina, stroke (CVA), transient ischemic attack (TIA), combined coronary heart disease (CHD) (MI/angina), combined cerebrovascular (CVA/TIA), peripheral vascular disease, and mortality
  
  
• Progression of Cognitive Decline in Standardized Z-score Scale. Higher Z-scores Indicate Worse Performance. [ Time Frame: 6 months/annually ]
  Rate of annual change by cognitive domain in standardized Z-score scale. Higher Z-scores indicate worse performance. Best score = -2.0 Z-score change per year (improvement); worse score = 2.0 Z-score change per year (decline).
  
  

Participants will be studied in a randomized trial of 240 mg of Ginkgo biloba as compared to placebo in healthy men and women, at least 75 years old. The trial will last approximately 8 years. The intervention will be considered unsuccessful in those participants who succumb to dementia, including Alzheimer's Disease and vascular dementia. There are four clinical centers: Pittsburgh, PA; Hagerstown, MD; Winston-Salem, NC; and Sacramento, CA; and a Coordinating Center at the University of Washington, Seattle. There will be a clinic visit every 6 months to determine morbidity, mortality and change in cognition that will include repeat of ADAS, CDR, and 10 battery neuropsychological evaluation and informant interview. The primary endpoint is dementia, specifically Alzheimer's disease, secondary endpoint will include the incidence of vascular disease, changes in cognitive function scores over time, total mortality and changes in functional status. The diagnosis of dementia will be based on neuropsychological testing, neurological exam, MRI, functional measurements, and review by a central adjudication committee and classified by DSM IV, NINCDS criteria and ADRTC criteria for vascular disease.