Predictors of relapsing disease course following index event in myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD).

BACKGROUND:Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is an autoimmune disease that can present as a monophasic or relapsing disease course. Here, we investigate the predictors of developing relapsing disease with a focus on the index event. METHODS:MOGAD patients followed at Massachusetts General Hospital and Brigham and Women's Hospital were included. Data on demographic, clinical, and laboratory features were collected. Time-to-event survival analysis was performed using a Cox proportional hazards model. Univariate and multivariate regression analyses were performed. RESULTS:We included 124 patients with a diagnosis of MOGAD of which 62.1% (n = 77) were female. The median (IQR) onset age and follow-up time were 31 (16, 45), and 4.08 (2.2, 7.9) years respectively. In total, 40.3% (n = 50) of patients remained monophasic and, 59.7% (n = 74) developed a relapsing course. The median (IQR) time between the index event and the second attack was 3(2, 13.7) months. Starting maintenance therapy following the index event was associated with decreased risk of relapsing disease (HR:0.26; 95%CI: 0.12, 0.54; P < 0.001). Maintenance therapy with intravenous immunoglobulin (HR:0.1; 95% CI:0.01, 0.78, P = 0.02), rituximab (HR: 0.21; 95%CI: 0.08, 0.55; P = 0.001), and mycophenolate mofetil (HR: 0.27; 95%CI: 0.09, 0.77; P = 0.01) was associated with a decreased risk of relapsing disease course. A polyphasic first attack (HR:2.4; 95%CI:1.31, 4.4; P = 0.004) and high CSF protein (HR:2.06; 95%CI: 1.01, 4.16; P = 0.04) were associated with a relapsing course. CONCLUSIONS:In MOGAD patients, starting maintenance therapy following the index event reduces the risk of relapsing disease regardless of age, sex, and onset phenotype, while polyphasic first attack, and elevated CSF protein predict relapsing disease course.