WASHINGTON – A new set of recommendations issued by the American Academy of Neurology and the American Epilepsy Society should help clinicians to determine an individual approach for deciding whether to treat an adult patient with a first unprovoked seizure.
The new guideline notes that immediate treatment lowers the risk of a subsequent seizure by 35% over 5 years, but probably does not affect the eventual seizure outcome, first author Dr. Allan Krumholz said at the annual meeting of the American Academy of Neurology.
“Over the long term, immediate antiepileptic therapy won’t change the prognosis,” said Dr. Krumholz of the University of Maryland, Baltimore. “Over 5 years, it’s unlikely to improve the chance for sustained remission. However, I would add that, in general, the prognosis for these patients, whether they have immediate treatment or wait until after a second seizure, is generally good, with 75% of them becoming seizure-free on medication.”
Rather than providing a step-by-step treatment algorithm, the guideline stresses the importance of collaborative decision making between doctor and patient. It was cosponsored by the American Epilepsy Society and simultaneously published in Neurology (Neurology 2015;84:1705-13).
“This paper can’t give a simple, black-and-white recommendation about whether to immediately start antiepileptic medications,” Dr. Krumholz said at a press briefing. “What we can say – and what is most important – is that these decisions need to be made on an individual basis. Clinicians should weigh individual seizure recurrence risks against the risks and benefits of antiepileptic drugs [AEDs], and consider the preferences of patients.”
An AAN task force reviewed 47 studies on first-seizure treatment and trichotomized them based on their strength of evidence.
Ten studies (two class I and eight class II) addressed the risk of seizure recurrence. These found that the risk of a subsequent seizure is lowest shortly after the first, and increases over time, from 21% to 45% by 5 years. Seizure recurrence was lowest if the patient started an AED, although this finding was not based on randomized, controlled studies.
The risk of recurrence was doubled for patients who had a predisposing clinical factor: a prior brain lesion, abnormal structural imaging of the brain, an EEG with epileptiform waves, or a nocturnal seizure. Clinicians should take these findings into account when assessing patients for treatment, Dr. Krumholz noted.
Five studies (one class I and four class II) evaluated the risk of additional seizures over short- and long-term follow-up. These found that the majority will happen within the first year, and that immediate AED treatment reduces that risk by 35%.
Five studies identified the risk of adverse events associated with AED treatment (four class II and one class III). The incidence of side effects ranged from 7% to 31%. These studies included the medications phenytoin, phenobarbital, carbamazepine, valproic acid, and lamotrigine. However, the guideline noted, several of these are older medications that may not be as commonly used now as the newer-generation drugs. The document also noted that most side effects are dose-related and reversible on drug discontinuation.
The guideline is a good companion to AAN’s 2007 recommendations on evaluating an unprovoked first seizure in adults, Dr. Krumholz added.
Dr. Krumholz had no financial disclosures relevant to the guidelines.
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