Sex-specific associations between gut microbiota and myopia in adolescents: a clinical predictive modeling study

Myopia is a common refractive disorder in adolescents, and its association with the gut microbiota remains incompletely defined.

We performed 16S rRNA sequencing on fecal samples from 102 adolescents (49 myopic, 53 non-myopic; aged 6-18 years) and analyzed microbial diversity, taxonomy, function, and random forest-based classification, stratified by sex.

Myopic adolescents showed lower gut microbial richness (observed and Chao1, both P < 0.05) than non-myopic controls, but overall community structure did not differ. Sex-stratified analyses revealed that these diversity reductions occurred only in myopic males (all α-diversity indices, P < 0.01), not in females. Several genera differed between myopic and non-myopic males (e.g., lower Akkermansia, Alistipes, Oscillibacter; higher Veillonella, Sutterella), whereas fewer differences were found in females. Functional predictions indicated altered metabolism and immune pathways. A random forest model achieved moderate overall accuracy (AUC = 76.84%), with higher performance in males (89.13%) than females (69.21%).

Adolescent myopia is associated with reduced gut microbial richness and sex-specific compositional changes, particularly in males, underscoring the importance of sex in gut-eye axis research.