Treatment at Onset Predicts a Longer Time-to-Relapse After Index Event in Myelin Oligodendrocyte Glycoprotein Antibody-Associated Disease (MOGAD)
Negar Molazadeh1, Philippe-Antoine Bilodeau1, Rebecca Salky1, Gauruv Bose2, Tanuja Chitnis3, Michael Levy1
1Massachusetts General Hospital and Harvard Medical School, 2Brigham MS Center, Department of Neurology, Brigham and Women’s Hospital, Boston, MA, USA Harvard Medical School and Division of Neurology, Department of Medicine, The Ottawa Hospital and University of Ottawa; Ottawa Hospital Research Institute, ON, Canad, 3Brigham and Women's Hospital
Objective:
To identify the predictors of time-to-second attack in patients with MOGAD.
Background:
MOGAD is a demyelinating disorder which can cause optic neuritis, transverse myelitis or acute disseminated encephalomyelitis. It can be monophasic or relapsing. Predictors of time-to-second attack in patients with an index demyelinating event are unknown in MOGAD.
Design/Methods:
Patients with a definite diagnosis of MOGAD, who tested positive for MOG-IgG and who are followed at Massachusetts General Hospital and Brigham and Women’s Hospital were included. Data on key clinical and demographic features including sex, age, race, treatment at onset, time-to-second attack and time to third attack were collected. A time-to-event survival analysis was performed using a Cox proportional hazards model. Univariate and multivariate regression analysis was performed.
Results:
We included 84 patients who had a definite diagnosis of MOGAD.The average age at first attack was 30 (IQR 17.0-46.5), and 62% of patients (n=52) were female. Median follow-up was 5.04 years (IQR 2.65-10.40). In total, 61% (n=51) of patients had a second attack, of which, 68% (n=35) experienced a third attack. After the first attack, 52% (n=42) patients were started on maintenance treatment. First available MOG titer was less than 1:100 in 29% of patients (n=25), and 1:00 or greater in 71% (n=51) of patients. Treatment status after the first attack significantly predicted longer time-to-second attack (HR = 0.46, 95% CI 0.23-0.92, p=0.028). Higher MOG titer did not predict time-to-second attack (HR=0.90, 95% CI 0.51-1.59, p=0.71). When adjusting for other covariates, MOG titers were not significantly associated with time-to-second attack.
Conclusions:
Early treatment after an index demyelinating event in MOGAD predicts a longer time-to-relapse, while MOG-IgG titer does not affect time-to-second attack.