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all newly diagnosed unprovoked seizures (single seizures and newly diagnosed epilepsy) but would
be expected to be higher than the incidence of epilepsy in a population followed over a long period
of time, as not all people with a single seizure go on to develop epilepsy (defined as at least two
recurrent seizures). This was demonstrated in the Rochester study which followed a population
over a 50-year period. The incidence of a first unprovoked seizure was 61 per 100,000 compared
to the incidence of epilepsy of 44 per 100,00012. Overall, while difficult to confirm, the incidence
of first single unprovoked seizures is likely to lie somewhere in the range of 50 and 70 per 100,000
in industrialised countries but may be much higher in developing countries13.

In general, the incidence of epilepsy in developed countries is taken to be around 50 per 100,000
(range 40−70 per 100,000/year)14 while the incidence of epilepsy in resource-poor countries is
generally higher in the range of 100−190 per 100,000/year15. While many factors may be
contributing to this disparity, it has been shown that people from a socio-economically deprived
background are at higher risk of developing epilepsy16.

In a systematic review of incidence studies carried out, 40 studies were identified, nine of which
were prospective, and seven studies identified were from resource-poor countries. The median
incidence rate of epilepsy and unprovoked seizures was 47.4 and 56 per 100,000.When the analysis
was limited to studies of the highest quality, the median incidence rates for epilepsy and
unprovoked seizures decreased to 45 and 50.8 per 100,00017. In a systematic review of European
epidemiological studies, annual incidence rates in studies of all ages ranged from 43−47 per
100,000 person years18.

A more recent systematic review and meta-analysis identified 33 cohort studies with the median
incidence of epilepsy being 50.4 per 100,000 person years (interquartile range (IQR) 33.6, 75.6).
The median incidence was lower in high income countries (45.0; IQR 30.3, 66.7) compared to that
in low- and middle-income countries (81.7; IQR 28.0, 233.5)19.

The incidence of epilepsy in Italy in 2011, using a nationwide database (the Health Search CSD
Longitudinal Patient Database), was 33.5 per 100,000 person years with a higher incidence in
women (women 35.3, men 31.5) and the incidence being highest in people aged <25 years and ≥75
years. This represents one of the lowest incidence rates reported in a European population20.

While there are only few incidence studies from low- and middle-income countries, two recent
studies from rural Kenya21 and Benin22 provide important data on the incidence of epilepsy in sub-
Saharan Africa. In rural Kenya, in a cohort of 151,408 people, 194 developed (convulsive) epilepsy
over five years giving a minimum crude incidence rate of 37.6/100,000 person years (95% CI 32.7,
43.3) and adjusted for loss of follow-up an incidence of 77.0/100,000 person years (95% CI 67.7,
87.4). Incidence was highest in children aged 6–12 years (96.1/100,000 person years; 95% CI 78.4,
117.9)21. In the study from Benin22, 11,688 people were surveyed and 148 people with epilepsy
were identified over an 18-month period, with the prevalence estimated to be as high as 38.4 per
1000 (95% CI 34.9, 41.9). The mean annual incidence was 69.4 per 100,000 person years with an
estimated cumulative incidence of 104.2 per 100,000 person years.

Prevalence studies

Studies have shown prevalence rates for active epilepsy in developed countries of between 4 and
10 per 100015, although most studies give a prevalence rate of active epilepsy of 4−7 per 1000. In
a systematic review18 it was found that the range for prevalence rates in Europe was 3.3−7.8 per
1000 with a median prevalence rate of active epilepsy of 5.2 per 1000. Studies with the lowest