Identification of risk factors for relapse at initial onset in myelin oligodendrocyte glycoprotein antibody–associated optic neuritis using ophthalmic findings

Abstract Purpose To identify risk factors for relapse in patients with myelin oligodendrocyte glycoprotein antibody–associated optic neuritis (MOG-ON) during the onset event. Study design Retrospective cohort study. Methods We included 44 eyes of 44 Japanese patients with MOG-ON (median age 40.0 years [interquartile range 23.5–54.0]; male to female ratio 16:28) who visited Tohoku University Hospital between August 2013 and December 2024. We compared patient background characteristics; ophthalmic findings, including optical coherence tomography parameters; laboratory findings, including hematological, biochemical, and immunological parameters; anti-MOG antibody titers; and contrast-enhanced orbital MRI findings at baseline in relapse and non-relapse groups. Relapse risk was evaluated using a Kaplan–Meier survival analysis and a Cox proportional hazards regression. Results Nine of 44 (20.5%) patients relapsed during follow-up. The Kaplan–Meier analysis showed lower relapse-free survival in patients without eye-movement pain, those with a lower serum IgG level, and those with a thinner macular retinal nerve fiber layer (mRNFL; log-rank P=0.013, 0.049, and 0.040, respectively). In the age- and sex-adjusted Cox proportional hazards analysis, relapse risk was significantly associated with absence of eye-movement pain (hazard ratio [HR] 5.58, 95% confidence interval [CI] 1.35–23.04; P=0.018), a lower serum IgG level (HR 0.55, 95% CI 0.30–1.00; P=0.048), and a higher anti-MOG antibody titer (HR 1.98, 95% CI 1.05–3.71; P=0.034). Conclusion Baseline absence of eye-movement pain, lower serum IgG level, and higher anti-MOG antibody titer were associated with relapse risk in patients with MOG-ON. A thinner mRNFL may represent a potential marker of relapse-related outcomes.