Chen, John J

ObjectivePatients with myelin oligodendrocyte glycoprotein antibody (MOG‐IgG)‐associated disease (MOGAD) suffer from severe optic neuritis (ON) leading to retinal neuro‐axonal loss, which can be quantified by optical coherence tomography (OCT). We assessed whether ON‐independent retinal atrophy can be detected in MOGAD.MethodsEighty patients with MOGAD and 139 healthy controls (HCs) were included. OCT data was acquired with (1) Spectralis spectral domain OCT (MOGAD: N = 66 and HCs: N = 103) and (2) Cirrus high‐definition OCT (MOGAD: N = 14 and HCs: N = 36). Macular combined ganglion cell and inner plexiform layer (GCIPL) and peripapillary retinal nerve fiber layer (pRNFL) were quantified.ResultsAt baseline, GCIPL and pRNFL were lower in MOGAD eyes with a history of ON (MOGAD‐ON) compared with MOGAD eyes without a history of ON (MOGAD‐NON) and HCs (p < 0.001). MOGAD‐NON eyes had lower GCIPL volume compared to HCs (p < 0.001) in the Spectralis, but not in the Cirrus cohort. Longitudinally (follow‐up up to 3 years), MOGAD‐ON with ON within the last 6–12 months before baseline exhibited greater pRNFL thinning than MOGAD‐ON with an ON greater than 12 months ago (p < 0.001). The overall MOGAD cohort did not exhibit faster GCIPL thinning compared with the HC cohort.InterpretationOur study suggests the absence of attack‐independent retinal damage in patients with MOGAD. Yet, ongoing neuroaxonal damage or edema resolution seems to occur for up to 12 months after ON, which is longer than what has been reported with other ON forms. These findings support that the pathomechanisms underlying optic nerve involvement and the evolution of OCT retinal changes after ON is distinct in patients with MOGAD. ANN NEUROL 2022;92:476–485

Abstract Background: Optic neuritis (ON) is a frequent presentation of multiple sclerosis (MS), neuromyelitis optica spectrum disorder (NMOSD), and myelin oligodendrocyte glycoprotein-antibody disease (MOGAD) at onset. The pathophysiology underlying these diseases, especially MOGAD, is still being elucidated. While obesity has been reported to potentially be a risk factor for MS, this has not been explored in NMOSD or MOGAD. We aimed to investigate a possible association between obesity (body mass index [BMI] >30 kg/m²) and patients with MOGAD, NMOSD or MS. Methods: Multicenter non-interventional retrospective data collection from a first ever demyelinating attack of ON in patients subsequently diagnosed with MOGAD, NMOSD or MS between 2005-2020. The following data was collected: age, gender, ethnicity, BMI at disease onset and the etiology of ON after diagnostic work-up. A mixed model analysis was performed to assess the ability of obesity or BMI to predict MOGAD-ON and distinguish MOGAD-ON from NMOSD- and MS-ON. Main outcome measures included BMI in patients with acute ON and subsequent diagnosis of MOGAD, NMOSD or MS. Results: One-hundred and eighty-three patients were included: 44 with MOGAD, 49 with NMOSD, and 90 with MS. A higher BMI was significantly associated with a diagnosis of MOGAD-ON (p<0.001); in MOGAD patients the mean BMI was 31.6 kg/m² (standard deviation (SD) 7.2), while the mean BMI was 24.7 kg/m² (SD 5.3) in NMOSD patients and 26.9 kg/m² (SD 6.2) in MS patients. Mixed effects multionimal logistic regression, adjusted for age and gender with obesity as a binary variable revealed that obesity was associated with a higher odds ratio (OR) of a subsequent MOGAD diagnosis (OR 5.466, 95% CI: [2.039, 14.650], p = 0.001) in contradistinction with NMOSD. Conclusion: This study suggests an association between obesity and MOGAD. Our finding requires further exploration, but could have significant pathophysiologic implications if confirmed in larger prospective studies.