Ginkgo Biloba versus placebo in patients with normal tension glaucoma: a systematic review and meta-analysis

Gingko Biloba versus placebo em pacientes com glaucoma de pressão normal: uma revisão sistemática e metanálise

Purpose:  To compare the effect of Ginkgo Biloba extract (GBE) intake versus placebo as adjunctive therapy for normal tension glaucoma (NTG).

Methods:  PubMed, Cochrane, Embase and Web of Science databases were queried for randomized controlled trials (RCTs) and observational prospective or retrospective studies that compared GBE versus placebo in the settings of NTG. Outcomes included visual field mean deviation (MD), visual field pattern standard deviation (PSD), and adverse events. Heterogeneity was assessed using I² statistics, and a random-effects model was applied for analysis. Statistical analysis was conducted using the Review Manager 5.3.

Results:  A total of 4 studies (3 RCTs and 1 observational retrospective study) comprising 285 eyes with NTG (146 in the GBE group and 139 in the placebo group) were included. The follow-up duration ranged from 1 to 24 months. Pooled results revealed significant differences in mean change of visual field MD favoring the GBE group compared to the placebo group (MD: -1.74 dB; 95%CI -2.97 to -0.51; p = 0.006; I² = 0%). No significant differences were observed between groups in visual field PSD. No adverse events were reported in the GBE group.

Conclusion:  GBE as adjunctive therapy for NTG may be associated with improvement in visual field MD and appears to have a favorable safety profile; however, further studies are needed to confirm these findings.

Keywords:
Ginkgo Biloba; Flavonoides; Glaucoma