APOE and snowflake vitreoretinal degeneration: SVD and AD share overlapping risk factor profiles, including hypertension, diabetes mellitus, smoking, hyperlipidemia, and apolipoprotein E ε4, while SVD is independently linked to stroke, cognitive decline, gait disturbance, and late-life dementia (Gorelick et al., 2011; Kim et al., 2020).