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clinical data allows the reclassification of some cases clinically diagnosed as generalised seizures
to partial seizures with secondary generalisation, as was shown in a study from Bolivia40. Two-
thirds of cases were clinically diagnosed with generalised seizures (34% partial seizures) but, on
the basis of electro-clinical data, the proportion with partial seizures increased to 53%.

Epilepsy syndromes are classified according to the ILAE classification41 which is based on age,
clinical semiology and electrophysiological findings. However many cases in epidemiological
studies are unclassifiable according to the current classification42. A community-based study from
Iceland35 showed the following syndrome frequencies in the cohort (with calculated incidence
rates): juvenile myoclonic epilepsy (JME) (1%; incidence 0.7 per 100,000 person years), childhood
absence epilepsy (1%; incidence 0.8 per 100,000 person years), benign rolandic epilepsy (5%;
incidence 2.8 per 100,000 person years), West syndrome (1%; incidence 0.007 per 100,000 person
years), Landau-Kleffner syndrome (0.4%; incidence 0.2 per 100,000 person years), benign familial
infantile convulsions (0.6%; incidence 0.3 per 100,000 person years), primary reading epilepsy and
benign occipital epilepsy (0.1%; incidence 0.2 per 100,000 person years), respectively (Table 1).

The use of medical services over a 12-month period has been studied in a series of 1628 prevalent
cases identified randomly in a population-based survey, the cases ascertained being on antiepileptic
drug (AED) therapy45. In the prior 12-month period 28% had been seen by a specialist (and 81%
had been seen by a specialist at some point), 87% had been seen by their general practitioner for
epilepsy and 9% had not been seen by any doctor. In the previous 12 months, 18% had attended an
accident and emergency (A&E) department and 9% had been admitted to hospital because of their
epilepsy. A total of 43% had attended an A&E department and 47% had been admitted to a hospital,
2% more than 10 times, at some point because of their epilepsy. Most (65%) were on monotherapy,
while 35% were on polytherapy.

Despite the fact that AED therapy is widely available, many people with active epilepsy go
untreated, particularly in resource-poor countries. Reasons for this treatment gap (TG) are many
and in a recent systematic review of this problem in resource-poor countries, the pooled mean of
the TG prevalence was 56% (95% CI 33100). When analysed by region, the mean prevalence of
TG was 64.3% (95% CI 24.3100) in Asia, 55.4 (95% CI 39.078.6) in Latin America and 48.9
(95% CI 14.3100) in Africa. The TG was higher in rural areas (73.3; 95% CI 49.5100) compared
to urban areas (46.8; 95% CI 34.164.2). The principal causes identified for TG were inadequate
skilled manpower in the local health service (median 70%; range 6476), cost of treatment (median
62%; range 1190) and unavailability of drugs (median 53%: range 1884)46.

Effective strategies aimed at reducing the TG in developing countries need to be identified and
implemented in order to improve the prognosis of people with epilepsy living in such countries47.

Conclusions

Further epidemiological studies should be prospective population-based incident cohort studies.
Such studies should focus on the temporal changes in the incidence of epilepsy in defined
populations. Furthermore research should focus on differences (real or perceived) between people
of different ethnicity and social background. This may, in turn, lead to the identification of inherent
risk factors in particular sub-populations for the subsequent development of epilepsy.