Clinical difference after the first optic neuritis between aquaporin-4-IgG-associated and myelin oligodendrocyte glycoprotein-IgG-associated disorders

Abstract

Objective: To investigate the difference in clinical course after the first optic neuritis (ON) between aquaporin-4 IgG-associated disorder (AQPAD) and myelin oligodendrocyte glycoprotein-IgG-associated disorder (MOGAD) METHODS: In this study, 31 eyes in 24 patients with AQPAD and 26 eyes in 18 patients with MOGAD were included. The clinical course for the first 6 months after the first ON was monitored by a retrospective cohort study. Best-corrected visual acuity (BCVA) was observed before the onset and at nadir, 2 weeks (2 W), 1 month (1 M), 2 months (2 M), 3 months (3 M) and 6 months (6 M). The decimal BCVA was converted to the logarithm of the minimal angle of resolution (logMAR) for statistical analyses.

Results: MOGAD eyes showed longer median number of days from ON onset to nadir (6.0 vs. 11.5, P = 0.012) and to treatment (7.0 vs. 11.0, P = 0.020) than AQPAD eyes. The median logMAR was higher in AQPAD eyes than in MOGAD eyes at nadir (2.00 vs. 1.77, P = 0.050), 2 W (1.85 vs. 0.40, P = 0.001), 2 M (0.023 vs. - 0.079, P = 0.032) and 3 M (0.046 vs. - 0.079, P = 0.002). The median time to recovery of BCVA to 0.7 was longer in AQPAD eyes than in MOGAD eyes (44.0 vs. 21.0 days, P = 0.024), but that to BCVA 1.0 was not different between the two disorders (168.0 vs. 40.0 days, respectively, P = 0.056).

Conclusion: Compared with MOGAD eyes, AQPAD eyes tended to show worse visual outcome even during the first ON episode.

Keywords: Aquaporin-4; Myelin oligodendrocyte glycoprotein; Neuromyelitis optica spectrum disorder; Optic neuritis; Visual acuity.