Seizure outcomes in patients with anti‐NMDAR encephalitis: A follow‐up study

Summary Objective To evaluate the long‐term seizure outcome and potential factors associated with seizure outcome in patients with anti‐ N ‐methyl‐ d ‐aspartate receptor (anti‐ NMDAR ) encephalitis. Methods In the setting of a prospective, single‐center, longitudinal cohort study, 109 patients were evaluated with ongoing follow‐up. Patients underwent clinical evaluation every 3 months. Seizure outcomes and the potential risk factors were assessed with a median follow‐up of 24 months (6–60 months). Results Of 109 patients (47 men; 62 women) with anti‐ NMDAR encephalitis, 88 patients (80.7%) had reported seizures at acute phase, including single seizure (17/88, 19.3%), repetitive seizures (27/88, 30.7%), nonrefractory status epilepticus (22/88, 25%), refractory status epilepticus (SE; 13/88, 14.8%), and super refractory status epilepticus (9/88, 10.2%). Seizure was more likely to recur in patients with tumor presence, status epilepticus ( SE ) development, coma, or intensive care unit (ICU ) admission in the acute phase (p < 0.05). Seizure freedom was achieved within 2 years in all patients. More than 80% of the whole cohort with acute seizures had their last seizure within 6 months of disease onset. Significance Seizure is a common feature in the acute stage of anti‐ NMDAR encephalitis but not thereafter. The presence of tumor, SE , coma, and/or ICU admission in the acute phase predicts early seizure occurrence after the acute phase. Seizure freedom was typically achieved in our follow‐up, and long‐term use of antiepileptic drugs may not be necessary.