Mendelian randomization analysis revealed a gut microbiota-eye axis in acute anterior uveitis

Abstract

Observational studies suggest that gut microbiome (GM) may contribute to acute anterior uveitis (AAU) development, but causality remains unclear. This study was conducted to test whether specific GM taxa were causally associated with AAU. The GM data were obtained from the DMP, which included 7738 individuals’ faecal samples and an analysis of host genotype-taxa abundance associations. The AAU data were derived from the FinnGen Consortium (8624 cases and 473,095 controls). We primarily employed the inverse-variance weighted method, complemented by supplementary sensitivity analyses. Higher abundance of Lachnospiraceae noname (OR = 0.86, 95% CI 0.81–0.91, P = 5.7 × 10-8), Alistipes finegoldii (OR = 0.87, 95% CI 0.78–0.96, P = 0.008), Erysipelotrichaceae (OR = 0.90, 95% CI 0.81–0.99, P = 0.037), Erysipelotrichia (OR = 0.90, 95% CI 0.81–0.99, P = 0.037), Erysipelotrichales (OR = 0.90, 95% CI 0.81–0.99, P = 0.037), and Bacteroides ovatus (OR = 0.93, 95% CI 0.87–1.00, P = 0.039) predicted a lower AAU risk. Conversely, higher abundance of Bifidobacterium catenulatum (OR = 1.06, 95% CI: 1.02–1.10, P = 0.005), Bacteroides coprocola (OR = 1.11, 95% CI: 1.02–1.21, P = 0.014), Parabacteroides unclassified (OR = 1.12, 95% CI 1.03–1.22, P = 0.010), and Prevotella (OR = 1.15, 95% CI: 1.01–1.29, P = 0.029) predicted a higher AAU risk. The results also showed a reverse causation from AAU to Bifidobacterium catenulatum (OR = 1.39, 95% CI: 1.03–1.86, P = 0.005). This study suggests that specific GM is causally associated with AAU risk, warranting more mechanistic validation and clinical trials.