Effects of Ginkgo biloba extract on cognitive function and blood pressure in elderly subjects

In this randomized, double-masked study, we assessed the effects of a Ginkg o biloba (GB-8) extract on elderly volunteers with age-related cognitive dy sfunction. A total of 260 subjects were tested to obtain a homogeneous grou p of 60 elderly subjects with mild-to-moderate cognitive impairment, as def ined by a clinical rating scale. The subjects were allocated to one of thre e groups and received either GB-8 40 mg or 80 mg or placebo three times dai ly for 3 months. Before therapy was started and after 1 and 3 months of tre atment, standardized testing of attention, concentration, and memory was pe rformed. The subjects completed self-assessments before and after 3 months of therapy, and arterial blood pressure was measured at the same intervals. Clinical ratings were done before and after 3 months of treatment. Six sub jects withdrew from the study, whereas 54 subjects (31 women and 23 men; me an age, 74 years; age range, 61 to 88 years) completed the study. After ran domization, the groups were similar with respect to age, social class, leve l of education, and demographic characteristics. Objective test results sho wed that attention, concentration, and short-term verbal memory improved si gnificantly in subjects receiving the low-dose (standard) treatment. Simila r improvements were seen in the results of the self-assessment test and the clinical rating. Diastolic blood pressure decreased significantly during l ow-dose treatment. Treatment with the GB-8 extract was found to improve obj ective measures of cerebral function in elderly subjects with mild-to-moder ate cognitive impairment; the improvement appeared to be clinically relevan t. The possible antihypertensive action of Ginkgo biloba extract is suffici ent to warrant further investigation.