When a patient goes to their doctor because they have had one or two seizures, it can be difficult for a doctor to decide whether to start anti-epileptic drug (AED) treatment at once or not. Should they treat the seizures, which might never recur, and expose the patient to the negative effects of drug treatment, or should the doctor wait to see if the epilepsy develops further? A study reported last year (the
Medical Research Council Multicentre trial for Early Epilepsy and Single Seizures (MESS)) found that immediate AED treatment reduces the occurrence of seizures in the first 1-2 years after diagnosis, but does not affect long-term remission (seizure freedom) rates in patients with single or infrequent seizures.

The MESS trial team in Liverpool and Cambridge have now further investigated whether there are any characteristics of a patient or their treatment that can be used to predict whether they would have more seizures. In their study, published in the April edition of Lancet Neurology, they found that the number of seizures a patient had experienced by the time they went to a doctor was an important predictive factor of the future development of epilepsy: the greater the number of seizures reported at presentation, the more likely the patient was to need continuing ongoing treatment in the long term. Other indicators of needing continuing treatment were the presence of a neurological disorder and having an "abnormal" EEG scan (electroencephalogram).

Patients can be divided into three groups:

• At high risk of further seizures: patients with two or more of the following features at presentation: 2-3 seizures, neurological disorder or abnormal EEG; OR more than 3 seizures
• At medium risk of further seizures: patients with one of the following features at presentation: 2-3 seizures, neurological disorder or abnormal EEG
• At low risk of seizures: patients having had only one seizure at presentation.

This analysis shows that it is possible to predict which patients would benefit from immediate treatment for epilepsy. Medium and high risk patients would definitely benefit from being identified early.