In order to help doctors treat the millions of people who experience their first seizure each year, the American Academy of Neurology and the American Epilepsy Society have released a new guideline on how to treat a first seizure. The guideline is published in Neurology, the medical journal of the American Academy of Neurology (AAN), and will be presented at the AAN Annual Meeting in Washington, DC, April 18-25, 2015, which is the world's largest gathering of neurologists.
One in 10 people worldwide have a first seizure in their lifetime. According to The International League Against Epilepsy, epilepsy is defined as one or more seizures with a high likelihood of recurrence, not due to another immediately triggering cause, such as low blood sugar.
The guideline, which reviewed all available evidence, found that taking epilepsy drugs immediately after a first seizure may reduce the risk of having another seizure. The decision to treat after a first seizure is complex because doctors must consider the risks and benefits for each individual patient.
"This is a valuable new guideline that could change the approach many doctors take to treating a first seizure and could improve patients' lives," said guideline author Allan Krumholz, MD, with University of Maryland School of Medicine and Fellow of the American Academy of Neurology. "About 150,000 adults have an unprovoked first seizure in the United States each year. Even one seizure is traumatic and affects a person's life in many social ways, such as driving a car, employment options, falling risks and the fear of having another seizure in public. This guideline clarifies when risk factors put individuals at greater risk."
Seizures that are "unprovoked" happen for no immediately known reason. According to the Institute of Medicine, one in 26 Americans will develop epilepsy in their lifetime.
The guideline shows there is strong evidence that for adults who have had a first seizure, the risk of another seizure is greatest within the first two years. The risk ranges from about a one-in-five chance, or 21 percent, to nearly a one-in-two chance, or 45 percent.
The guideline also found strong evidence that the risk of a second seizure is greatest in people with a previous brain problem, such as head injury, stroke, or brain tumor and in those with an EEG test result that shows signs of epilepsy. The analysis shows moderate evidence that the risk is greatest in people with a significant abnormality on imaging tests of the brain and in those who had a seizure during sleep.
The guideline found moderate evidence that immediate treatment with an epilepsy drug can lower this risk.
However, moderate evidence also shows that over the longer term of more than three years, immediate treatment with an epilepsy drug, rather than waiting for another seizure before treating, is unlikely to increase or decrease the likelihood of long-term improvement or seizure freedom.
The guideline notes that aside from affecting lifestyle choices, epilepsy drugs carry risks of side effects ranging from seven to 31 percent.
"This guideline does not give a simple, black-and-white recommendation whether an adult should immediately be started on an epilepsy drug," said Jacqueline French, MD, with the New York University Langone Comprehensive Epilepsy Center and Fellow with the American Academy of Neurology. "What is most important is that the decision whether to immediately treat a first seizure requires meaningful conversation between patient and doctor so that the patient's individual circumstances, balance of risks and benefits, and personal preferences are understood and accounted for."
The guideline was endorsed by the American Neurological Association and the World Federation of Neurology.
The guideline was supported by the American Academy of Neurology.