Moving right along, let us take a look at risk of recurrence and subsequent epilepsy.
What is the longterm prognosis/risk of epilepsy?
The short answer – great/low. Nelson et al in the NEJM noted that the risk of epilepsy at age after at least one febrile seizure was 2%. This is a 100% increase over the baseline prevalence – which is 1%. They also noted that “in children whose neurologic or developmental status was suspect or abnormal before any seizure and whose first seizure was complex epilepsy developed at a rate 18 times higher than in children with no febrile seizures (92 vs. 5 per 1000; P less than 0.001).” So, complex seizures may increase the risk of epilepsy more – makes sense.
Annegers et al found that there were three risk factors for developing epilepsy. With none of those factors the risk of epilepsy was 2.4%, one 6-8%, Two 17-22%, and all three 49%.
- Focal seizures
- Prolonged seizures
- Repeated episodes within 24 hours during the same illness
Do any children suffer permanent neurologic sequelae?
Probably not… Population studies in the US, UK and Denmark showed that the risk of long term badness (cognitive or functional problems) is basically zero. Take my word for it, or look up these three studies.