Attia, A., Rapp, S.R., Case, L.D., D'Agostino, R., Lesser, G., Naughton, M., . . . Shaw, E.G. (2012). Phase II study of Ginkgo biloba in irradiated brain tumor patients: Effect on cognitive function, quality of life, and mood. Journal of Neuro-Oncology, 109, 357–363.

To test the hypothesis that ginkgo biloba may be helpful for radiation-induced cognitive impairment

120 mg ginkgo biloba was given for 24 weeks and then discontinued for 6 weeks as a washout period. Tests were administered at baseline, 12 weeks, 24 weeks, and 30 weeks after the initial evaluation.

• The study reported on a sample of 34 patients with a median age of 47 years (range 22–82).
• Participants were 32% male and 68% female.
• Cognitive impairment and depressed mood were present in the sample at baseline.
• All participants had brain irradiation six or more months prior to study entry and no evidence of disease progression.

• Single site
• Outpatient    
• North Carolina

Phases of Care: Late effects and survivorship

An open label phase II study design was used.

• Mini mental state exam
• Trail Making Test parts A and B
• Digit Span Test
• Revised Rey-Osterrieth Complex Figure Test
• Verbal fluency (FAS) test
• California Verbal Learning Test II
• FACT-Brain
• Profile of Mood States (POMS)

Trail Making Test (TMT) results improved significantly from baseline to 24 weeks; however, TMT-Part B continued to improve significantly from week 24 to week 30 after ginkgo was stopped. It is unclear if changes seen demonstrate improvement with treatment or learning effect. Scores for immediate and delayed recall on the Rey-Osterreith Figure were better (p < 0.0002), but these were not measured and reported at 30 weeks. There were no other changes in mental function scores. POMS scores improved for overall mood for the first 24 weeks and then began to decline. By 24 and 30 weeks, only 19 patients remained in the study. Most common toxicities reported were cognitive issues and memory problems. Five patients (16%) discontinued treatment because of gastrointestinal symptoms. One patient discontinued treatment because of intracranial bleed in one patient. Another five patients (16%) discontinued treatment because of no perceived benefit.

Findings from the study do not provide clear support for the effectiveness of gingko biloba on cognitive impairment caused by brain irradiation.

• The study had a small sample size with less than 30 participants.
• A risk of bias was possible because there was no control group, no blinding, and no random assignment.
• Findings were not generalizable.
• Subject withdrawals were greater than or equal to 10% of participants.
• There was a potential testing effect in the study.

Findings do not support effectiveness of gingko biloba to improve cognitive function in patients who have impairment associated with brain radiation.