[First spontaneous epileptic crisis in childhood: risk of relapse and prognostic factors]

Knowing the risk of relapse after a first epileptic crisis is important because of its repercussion on the patient. The prognosis is uncertain in some types of crisis.

To find the probability of relapse and risk factors after a first spontaneous epileptic convulsive crisis, focal or generalized, occurring in childhood or adolescence.

We followed a cohort of 139 patients from the Health District of Hospital General of Albacete who had had this type of crisis before the age of 14. Patients with acute symptomatic, febrile or neonatal convulsions were excluded. The probability of relapse was calculated using Kaplan-Meier curves, and multivariate analysis was carried out.

The probability of relapse 24 months after the first epileptic crisis is 70% and after 76 months is 75%. Of a series of variables analyzed, the only one associated with increased risk of relapse was the 'aetiology': the relative risk of relapse in patients with previous symptomatic aetiology is 2.1 as compared with those of idiopathic aetiology (p < 0.001).

Patients who have had a first focal or generalized convulsive epileptic crisis in childhood have a 75% probability of developing epilepsy over the subsequent 6 years; this risk is greater in those with a previous symptomatic aetiology, so this should be taken into account when deciding on the treatment of these patients.