A genetic perspective on retinal thinning in Parkinson's disease: Direct damage or comorbid glaucoma?

This study used Mendelian randomization to reveal a causal link between Parkinson's disease (PD) and retinal nerve fiber layer thinning. Moreover, the tremor-dominant (TD) PD subtype was genetically associated with increased glaucoma risk, suggesting PD, especially TD subtype, may contribute to retinal neurodegeneration via both direct and glaucoma-related pathways.