Ginkgo biloba for mild cognitive impairment and Alzheimer's disease : a systematic review and meta-analysis of randomized controlled trials

Background: Ginkgo biloba is a natural medicine used for cognitive impairment and Alzheimer’s disease. The objective of this review is to explore the effectiveness and safety of Ginkgo biloba in treating mild cognitive impairment and Alzheimer’s disease. Methods: Electronic search was conducted from PubMed, Cochrane Library, and four major Chinese databases from their inception up to 1st December, 2014 for randomized clinical trials on Ginkgo biloba in treating mild cognitive impairment or Alzheimer’s disease. Meta-analyses were performed by RevMan 5.2 software. Results: 21 trials with 2608 patients met the inclusion criteria. The general methodological quality of included trials was moderate to poor. Compared with conventional medicine alone, Ginkgo biboba in combination with conventional medicine was superior in improving Mini-Mental State Examination (MMSE) scores at 24 weeks for patients with Alzheimer’s disease (MD 2.39, 95% CI 1.28 to 3.50, P<0.0001) and mild cognitive impairment (MD 1.90, 95% CI 1.41 to 2.39, P