Abstract
Purpose :
Several studies provided compelling evidence that the immune system is involved in the pathogenesis of open-angle glaucoma (OAG). Reactive oxygen species and cytokines produced by the gut microbiome may play a role in this process, traveling from the gut mucosa to the eye. Therefore it is of interest to find changes in the microbiome of patients with OAG.
Methods :
Population-based cohort study. All participants underwent extensive ophthalmic examinations, including intra-ocular pressure (IOP), retinal nerve fiber layer (RNFL), and vertical cup-to-disc ratio (VCDR) measurements, and provided a stool sample. A 16S rRNA gene profile dataset was generated and PICRUSt tool was used to obtain predicted bacterial functions. Beta-diversity was calculated and compared using Bray-Curtis dissimilarity matrices. The relationship between alpha-diversity and OAG and OAG-associated parameters was assessed by logistic and linear regression analyses, respectively, adjusted for age, sex, body-mass index, and medication use. The same analyses were performed to assess these relationships at taxa level.
Results :
When comparing OAG cases with controls, no differences in alpha- and beta diversity were observed. On taxa level, a higher abundance of the family Rikenellaceae, more specifically the genus Alistipes (OR [95% CI]=1.69 [1.17-2.54]), was associated with higher OAG risk (OR [95% CI]=1.60 [1.11-2.38]). The family Clostridiaceae1 was associated with a lower IOP (estimate=-0.121; p-value=0.001) and smaller VCDR (estimate=-0.024; p-value=0.002). At genus level, Clostridiumsensustricto1 showed the same effects (estimate=-0.120; p-value=0.002 and estimate=-0.023; p-value=0.003, respectively). Predicted functional metagenome analysis showed an association between the lysosome and OAG (OR [95% CI]=2.50 [1.18-4.68]) and RNFL (estimate=-5.273; p-value=0.007).
Conclusions :
This study showed associations between the gut microbiome and OAG, as well as with OAG-associated parameters. Predicted functional metagenome analysis revealed the lysosome as potentially interesting for the development of glaucoma. Although replication studies are necessary, our findings display a new pathway in the pathogenesis of glaucoma.
This is a 2021 ARVO Annual Meeting abstract.