Treatment of first tonic-clonic seizure does not affect mortality: long-term follow-up of a randomised clinical trial

Abstract

Background: Information on the effects of early treatment of seizures on mortality is scarce. The authors assessed the survival of patients with a first generalised tonic-clonic seizure, randomised to immediate treatment (treated) versus treatment only in the event of seizure recurrence (untreated), over a 20-year period.

Methods: The authors followed 419 patients. The median follow-up was 19.7 years (range 0.2-21.5) for a total of 7867 person-years.

Results: 40 persons (9.6%) died during follow-up, 19 (8.9%) treated and 21 (10.3.%) untreated. The probability of surviving was 100% at 1 year, 97% (95% CI 95% to 99%) at 5 years, 94% (91-97) at 10 years and 91% (87-95) at 20 years in treated patients and 100%, 98% (95-100), 97% (94-99) and 89% (85-94), respectively, in untreated patients (p=0.7). After adjustment for treatment of first seizure and putative risk factors (gender, age, seizure type, previous uncertain seizures, family history of seizures, pre-, peri- and postnatal risk factors, remote aetiological factors for epilepsy, abnormal neurological examination, CT or MRI abnormalities, EEG abnormalities and acute treatment), only the presence of aetiological factors for epilepsy predicted a higher mortality (HR 3.4, 95% CI 2.5 to 4.3%; p<0.01). Patients with remote aetiological factors and who did not achieve 5-year remission had the poorest survival.

Conclusion: Starting antiepileptic treatment immediately after the first generalised tonic-clonic seizure or only after seizure recurrence did not affect survival over the following 20 years.