An evidence-based approach to the first seizure.

Evidence-based care (EBC) is an explicit approach to applying the best evidence to the care of individual patients. We outline the basic principles of EBC and apply them to various clinical questions pertaining to a patient presenting with a first seizure, providing a summary of the best available evidence for each question. Depending on the question at hand, the evidence derives from retrospective, prospective, and randomized controlled studies in children and adults. There is solid evidence that early seizure recurrence is reduced by early initiation of AEDs. A meta-analysis of six randomized trials revealed an average absolute risk reduction of 34% (95% CI 15-52) with AED therapy. However, the prognosis for the development of epilepsy is not altered by early intervention. EEG epileptiform abnormalities, family history of epilepsy, imaging lesions, and remote symptomatic seizures increase the risk of recurrence, and impact the risk-benefit ratio of treatment after a single event. In the end, clinicians must evaluate patients with a first unprovoked seizure on a case-by-case basis to determine the appropriateness of treatment with a given AED.