Editor’s Note: The ACEP Clinical Policies Committee regularly reviews guidelines published by other organizations and professional societies. Periodically, new guidelines are identified on topics with particular relevance to the clinical practice of emergency medicine. This article highlights recommendations for management of an unprovoked first seizure in adults developed by the American Academy of Neurology and the American Epilepsy Society in 2015.

Seizures are no stranger in the emergency department: There are more than 1 million ED visits annually for seizures in the United States, and up to 150,000 of those visits are because of unprovoked, first-time seizures.^1,2

There are many questions that arise when caring for these patients—most importantly, should antiepileptic drug (AED) therapy be started? How likely is a recurrent seizure? Would starting AED therapy improve outcomes? What harms are associated with AEDs? The American Academy of Neurology and American Epilepsy Society recently developed an updated guideline on the management of unprovoked first seizure in adults that addresses these important questions.³

The guideline developers conducted a systematic literature review to answer four clinical questions; 47 articles provided the evidence for the recommendations. The strength of each recommendation was graded as A (well-established), B (probably effective), C (possibly effective), or U (data inadequate or conflicting).

Question 1: For the adult who presents with an unprovoked first seizure, what are the risks for seizure recurrence?
Conclusions: The risk of recurrence is highest within the first two years (21 to 45 percent), and especially in the first year (Level A). Recurrence risk is higher (increased relative risk greater than 2.0) in patients with a prior brain lesion or insult causing the seizure (stroke (Level A), trauma (Level A), CNS infection, cerebral palsy, cognitive developmental disability), an EEG with epileptiform abnormalities (Level A), a significant brain-imaging abnormality (Level B), and a nocturnal seizure (Level B).
The broad range of early seizure recurrence (21 to 45 percent) included all comers; in patients without any of the high-risk features, recurrence was only 10 percent, 24 percent, and 29 percent at one, three, and five years, respectively. This data may help frame providers’ discussions with patients as to the pros and cons of initiating AED therapy, as many patients encountered in the emergency department fall into this “low-risk” category.

Question 2: For the adult presenting with an unprovoked first seizure, does immediate treatment with an AED change the short-term (two-year) prognosis for seizure recurrence?
Conclusion: For adults presenting with an unprovoked first seizure, immediate AED therapy is likely to reduce the absolute risk of recurrence by about 35 percent within the subsequent two years (Level B) when compared with no treatment. Initiation of AED therapy hasn’t been shown to affect quality of life (Level C).
While seizure risk may be reduced by 35 percent, time to initiation of AED therapy ranged from one to 12 weeks after the first-time seizure occurred. Outpatient management and the decision to start AED therapy may be deferred to a neurologist or primary care physician if adequate outpatient follow-up is arranged. Only one small study addressed quality-of-life outcomes, and it showed no significant difference between treated and untreated patients.