Does Bacopa monnieri improve memory performance in older persons? Results of a randomized, placebo-controlled, double-blind trial.
キーワード
概要
OBJECTIVE
The objective of this study was to investigate the effectiveness of Bacopa monnieri Linn. for improvement of memory performance in healthy older persons.
METHODS
This was a randomized, double-blind, placebo-controlled trial.
METHODS
The trial took place in Lismore, NSW, Australia between February and July 2005. Ninety-eight (98) healthy participants over 55 years of age were recruited from the general population.
METHODS
Participants were randomized to receive an extract of Bacopa monnieri called BacoMind(TM) (Natural Remedies Pvt. Ltd.), 300 mg/day, or an identical placebo. Following screening, neuropsychologic and subjective memory assessments were performed at baseline and at 12 weeks.
METHODS
Audioverbal and visual memory performance were measured by the Rey Auditory Verbal Learning Test (AVLT), the Rey-Osterrieth Complex Figure Test (CFT), and the Reitan Trail Making Test (TMT). Subjective memory performance was measured by the Memory Complaint Questionnaire (MAC-Q).
RESULTS
One hundred and thirty-six (136) subjects volunteered; 103 met entry criteria, 98 commenced, and 81 completed the trial. Bacopa significantly improved verbal learning, memory acquisition, and delayed recall as measured by the AVLT: trial a4 (p = 0.000), trial a5 (p = 0.016); trial a6 (p = 0.000); trial a7 (delayed recall) (p = 0.001); total learning (p = 0.011); and retroactive interference (p = 0.048). CFT, MAC-Q, and TMT scores improved but group differences were not significant. Bacopa versus placebo caused gastrointestinal tract (GIT) side-effects.
CONCLUSIONS
Bacopa significantly improved memory acquisition and retention in healthy older Australians. This concurs with previous findings and traditional use. Bacopa caused GIT side-effects of increased stool frequency, abdominal cramps, and nausea.