Gingko Biloba Extract (EGb 761) Improves Cognitive Assessment Scores Relating to Delayed Recall and Language in Post-Stroke Patients

by | Jun 19, 2023 | 2023, Botanicals, Brain Health, Cognitive Health, Ginkgo Biloba, Stroke

Written by Taylor Woosley, Staff Writer. 24-week consumption of the Gingko biloba leaf extract EGb 761, according to the clinicians’ global ratings, shows that 80.2% of participants taking EGb 761 improved compared to baseline versus 20.8% of participants who received standard treatment. 

gingko biloba - botanicalsStroke is a leading cause of adult disability in the United States and the second leading cause of death worldwide1. Post-stroke cognitive impairment (PSCI) is one of the major complications after stroke and is frequently underdiagnosed2. The core domains for PSCI include executive function, memory, attention, language, and visuospatial function, while executive dysfunction and memory disorder are the most common clinical manifestation3.

EGb 761 is a standardized and extensively studied extract of Gingko biloba leaves that have been researched for its potential neuroprotective properties4. The active constituent of the leaves, ginkgolides and bilobalide, has been confirmed to inhibit the production of pro-inflammatory mediator and improve mitochondrial function5. Furthermore, ginkgolide has been shown to exert reparative effects that can help maintain the blood-brain barrier and provide a therapeutic effect for ischemic stroke6.

Cui et al. conducted a parallel-group, randomized, multicentric, open-label pilot study to assess whether EGb 761 at 240 mg/day for 24 weeks would provide cognitive benefits after an acute stroke. Subject inclusion consisted of being at least 50 years old and who did not score higher than 20 on the National Institutes of Health Stroke Scale (NIHSS) during 7-14 days after an acute stroke, with confirmed MRI scans indicating acute ischemic cerebral infarction. Additionally, participants needed a regular contact person who could provide information about the participant’s cognitive problems, neuropsychiatric symptoms, and functional abilities during the hospital stay. Subjects were randomized to either the EGb 761 group or the reference group. Both groups received standard treatment for a period of 24 weeks and the EGb 761 group took 2 tablets at 40 mg EGb 761 three times a day, for a daily dose of 240 mg.

Outcome measures included the change in cognitive status from baseline which was assessed by the validated Beijing version of the Montreal Cognitive Assessment (MoCA) at the end of the study. The MoCA focuses on various sub-domains of cognition including visuospatial/executive, memory, attention, language, and orientation. Additional tests such as the Hopkins Verbal Learning Test-Revised (HVLT-R), the Shape Trail Test (STT), the Verbal Fluency Test (VFT), the Digit Symbol Substitution Test (DSST) were also included in evaluation of cognition domains. The Neuropsychiatric Inventory (NPI), the Clinical Global Impression of Change (CGI-C), and the National Institutes of Health Stroke Scale (NIHSS) were used to assess clinical status of participants.

A total of 97 subjects in the EGb 761 group and 96 subjects in the reference group completed the study. Demographic characteristics and scale scores at baseline were similar between the two groups, besides the Neuropsychiatric Inventory (NPI) score, with a higher mean score being noted in the reference group. However, the difference did not reach statistical significance. Significant findings of the study are as follows:

  • Total MoCA scores at 24 weeks reached a significant difference in the EGb 761 group. Mean change from the baseline MoCA rating at week 24 was 2.92 in the EGb 761 group and 1.33 in the reference group (p < 0.001).
  • MoCA scores relating to delayed recall, orientation, and language showed significantly larger improvements in the EGb 761 group at 24 weeks (delayed recall: EGb 761 change 0.88 vs. reference 0.17, 95% CI, 0.31 to 1.10, p < 0.001; orientation: EGb 761® change 0.28 vs. reference −0.11, 95% CI, 0.18 to 0.60, p < 0.001; language: EGb 761® change 0.45 vs. reference 0.09, 95% CI, 0.06 to 0.66, p < 0.05).

Results of the study suggest that 24-week supplementation of EGb 761 slightly improved cognitive performance in subjects, particularly in areas of delayed recall, orientation, and language. Further long-term studies are necessary to better comprehend the beneficial effects of EGb 761 on cognition. Study limitations include the lack of a placebo group, the absence of biomarker evaluation regarding cognitive status, and the short duration of the study.

Source: Cui, Mei, Tongyao You, Yuwu Zhao, Ruozhuo Liu, Yangtai Guan, Jianren Liu, Xueyuan Liu, Xin Wang, and Qiang Dong. “Ginkgo biloba extract EGb 761® improves cognition and overall condition after ischemic stroke: Results from a pilot randomized trial.” Frontiers in Pharmacology 14 (2023): 857.

© 2023 Cui, You, Zhao, Liu, Guan, Liu, Liu, Wang and Dong. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.

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Posted June 19, 2023.

Taylor Woosley studied biology at Purdue University before becoming a 2016 graduate of Columbia College Chicago with a major in Writing. She currently resides in Glen Ellyn, IL.

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