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Table 1. Long-term prognosis studies in epilepsy.

Country Number Follow-up Proportion Proportion Study
USA12 N = 457 (years) 5YR TR (%) 5YR TR off design
AEDs (%)
20 70% Historic
50% incident
cohort
Japan13 N = 1868 10 58.3% N/A Retrospective
multi-
UK14 N = 194 12 64% 40% institutional
Japan15 N = 730 10-15 79.1% N/A study
Japan16 N = 143 18.9 62.8% 54.7% Retrospective
Sweden11 N = 107 10 64% 17.5% (P)
Retrospective
Finland17 N = 144 40 67% 58% (P)
61.9% Retrospective
Holland18 N = 413 14.8 70.9% (P)
Prospective
(All >17
years)
Prospective
(P)
Prospective
(P)

P=Paediatric study; 5YR TR=5-year terminal remission rate

recurrence after the second seizure within the first four years of follow-up, none had a relapse
in the subsequent three years. The majority of those with a third seizure had a further seizure,
with 31% of people who already had three seizures going on to have a fourth seizure at three
months, 48% at six months, 61% at one year and 78% at three years. As with single seizures,
the risk of further seizures is highest immediately after the last one. Similarly for children,
the risk of a third seizure was 57% at one year, 63% at two years and 72% at five years after
having a second seizure6.

Short- and medium-term prognosis

In a prospective study of children with newly diagnosed epilepsy followed up from the time
of diagnosis, 74% had achieved a period of remission (≥2 years’ seizure freedom), of whom
24% had a further seizure. In those who had a relapse, approximately 50% occurred when an
antiepileptic drug (AED) was being withdrawn or had been stopped9. In the NGPSE after
nine years, 86% had achieved a remission of three years and 68% a remission of five years.
The proportion in terminal remission by nine years was 68% for three years and 54% for five
years10. In a study of patients aged ≥17 with newly diagnosed epilepsy, at ten years’ follow-
up the cumulative remission rates were 68% (one year), 64% (three years) and 58% (five
years)11.

Long-term prognosis

Few studies have looked at the long-term prognosis of people with epilepsy and most are
retrospective and in paediatric cohorts (Table 1). In the Rochester study12, 65% had achieved
a five-year period of remission at ten-year follow-up and 76% at 20 years. At ten years after
diagnosis 61% were in terminal remission with 70% in terminal remission at 20 years. Of