Outcomes After Acute Plasma Exchange for Myelin Oligodendrocyte Glycoprotein Antibody–Associated Disease

Background and Objectives Data on the plasma exchange (PLEX) in myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) are limited. Herein, we evaluate outcomes after PLEX in MOGAD. Methods This international multicenter retrospective cohort study included patients from 18 tertiary care centers in 6 countries. Inclusion criteria included fulfillment of the 2023 International MOGAD panel criteria, receipt of at least 3 sessions of PLEX, and follow-up of ≥3 months after PLEX. Patients with coexisting neuroinflammatory disorders were excluded. We assessed the frequency of complete recovery (CR), clinically significant improvement (CSI), visual acuity (VA), and Expanded Disability Status Scale (EDSS). Logistic regression analyses were performed to identify predictors of CR and CSI. Results Of 234 patients, 135 (58%) were female. The median (interquartile range [IQR]) age at attack was 34 (IQR 22–49) years, and 42 (17%) were children. In 165 of 243 (68%), the attack treated with PLEX was the first attack. Attack phenotypes included 161 optic neuritis (235 eyes), 77 myelitis, 24 acute disseminated encephalomyelitis, 15 brainstem/cerebellar, 3 cerebral-cortical encephalitis attack, and 1 cerebral polyfocal deficit—36 with >1 core phenotypes. A total of 239 (99%) attacks were also treated with corticosteroids and 32 (13%) with IV immunoglobulins. VA in optic neuritis improved from 20/400 (20/70–hand motion) to 20/20 (20/20–20/30), p < 0.001, and EDSS decreased from a median of 4.0 (3.0–6.5) to 1.0 (0.0–2.5), p < 0.001. Of 229 attacks without subsequent attacks within 3 months, 100 Glossary aOR = adjusted odd ratio; CA = complete recovery; CF = count finger; CSI = clinically significant improvement; EDSS = Expanded Disability Status Scale; HM = hand motion; IVIG = IV immunoglobulin; logMAR = logarithm of the minimum angle of resolution; MOGAD = myelin oligodendrocyte glycoprotein antibody-associated disease; MS = multiple sclerosis; NMOSD = neuromyelitis optica spectrum disorder; PLEX = plasma exchange; VA = visual acuity. (44%) achieved CR and 213 (93%) CSI. The probability of CR was decreased with advanced age (adjusted odd ratio [95% CI] 0.97 [0.96–0.99] per year), higher EDSS worsening from baseline (0.66 [0.54–0.81] per 0.5 increment) and delayed PLEX (0.98 [0.96–0.99] per day). Advanced age (0.97 [0.96–0.99] per year) and delayed PLEX (0.95 [0.94–0.96] per day) decreased the probability of CSI. Discussion We observed favorable outcomes after PLEX in MOGAD attacks. However, advanced age and delayed initiation of PLEX were associated with a reduced probability of improvement. The absence of a control group limits our ability to differentiate PLEX effects from spontaneous recovery, prior corticosteroid response, or long-term immunotherapy. Future prospective studies are needed to assess the impact of PLEX on improvement. Classification of Evidence This study provides Class IV evidence that PLEX is associated with favorable clinical outcomes in patients with MOGAD.