Risk factor profiles and visual outcomes of non-arteritic anterior ischemic optic neuropathy in younger Chinese patients.

BACKGROUND: Non-arteritic anterior ischemic optic neuropathy (NAION) predominantly affects the elderly, although onset before age 50 is not uncommon. Systemic vascular diseases are the main risk factors in elderly patients, whereas ocular structural abnormalities may be associated with early-onset NAION. This study compared risk factor profiles and visual outcomes between young NAION patients and a selected contemporary comparison group of older patients consisting of consecutively enrolled cases within a predefined study period in China, to assess age-related differences. METHODS: In this single-center retrospective cohort study, patients diagnosed with NAION enrolled between May 2022 and February 2026 were stratified into a young group (aged < 50 years, n = 102) and a selected contemporary comparison group of older patients (aged ≥ 50 years, n = 111). Crucially, this older comparison group comprised consecutively enrolled cases within this predefined study period, rather than representing a random sample of all eligible older NAION patients. All patients underwent 6-month follow-up. Demographic, systemic, and ocular data, including best-corrected visual acuity (BCVA), visual field index (VFI), mean deviation (MD), and pattern standard deviation (PSD), were collected. Intergroup and intragroup comparisons were performed, and multivariable linear regression using a hybrid selection strategy (mandatory clinical covariates plus univariate screening) identified independent predictors of visual recovery. RESULTS: The young group included more males, had fewer bilateral cases, and exhibited higher smoking rates compared with this older comparison cohort (all P < 0.05). Conversely, this older comparison cohort had a higher prevalence of hypertension, cardiovascular disease, and peripapillary hyperreflective ovoid mass-like structure (PHOMS) (all P < 0.05). Inferior hemifield defects predominated in young patients, whereas diffuse defects were more common in this older comparison cohort. Significant within-group improvements in BCVA, VFI, MD and PSD were observed only in the young group (all P < 0.01), with between-group differences reaching significance only for MD. Multivariable analysis showed that younger age, shorter onset-to-presentation time, and better baseline BCVA were factors associated with greater BCVA recovery, though these associations should be interpreted cautiously given study limitations. CONCLUSIONS: Younger and older NAION patients exhibit distinct risk profiles and visual field defect patterns. While younger patients demonstrated significant within-group visual improvement, only the change in mean deviation (MD) differed significantly between groups, necessitating cautious interpretation of age-related recovery differences.