Short-term risk of relapse after a first unprovoked seizure in an adult population.

Objective: To evaluate the incidence of short-term recurrence (<1 month) after a first unprovoked seizure (FUS) and the associated risk factors.

Methods: This is a prospective monocentric one-year observational study on all consecutive adult patients admitted to the Emergency Department (ED) and diagnosed as FUS. Patients underwent neurological consultation at one and three months after the FUS. Demographic information, clinical examination and seizure features, seizure recurrence at 1 and 3 months, electroencephalogram (EEG), brain imaging, precipitating factors, seizure type, and prescribed antiepileptic drugs (AED) were prospectively collected.

Results: Among 140 patients diagnosed as FUS, 109 patients attended the neurological consultation at 1 month. FUS diagnosis was confirmed in 80/109 cases. Nine patients (11.2%) had seizure recurrence before the consultation at 1 month. Identified specific risk factors of short-term recurrence were focal seizure (P=0.015) and abnormal EEG in the first 48hours (P=0.048). In the group of patients followed for three months (38 patients), the risk of seizure relapse was 15.7%.

Conclusion: Most patients with FUS diagnosed in the ED did not present seizure recurrence within the first month, especially if no specific risk factors were present (focal seizure, abnormal EEG within first 48hours). The systematic use of prophylactic AED (benzodiazepines) is not recommended in the ED in the clinical setting of FUS. A specialized consultation within a one-month period is safe and adequate for FUS follow-up.