Epidemiological data for various forms of epilepsy can be difficult to ascertain due to variability in epilepsy classification and the age range of the population studied.
Studies based on the International League Against Epilepsy (ILAE) classification of epilepsy syndromes find the following:
Childhood absence epilepsy (CAE):[9]Hirsch E, French J, Scheffer IE, et al. ILAE definition of the idiopathic generalized epilepsy syndromes: position statement by the ILAE task force on nosology and definitions. Epilepsia. 2022 Jun;63(6):1475-99.
https://onlinelibrary.wiley.com/doi/10.1111/epi.17236
http://www.ncbi.nlm.nih.gov/pubmed/35503716?tool=bestpractice.com
[10]Kessler SK, McGinnis E. A practical guide to treatment of childhood absence epilepsy. Paediatr Drugs. 2019 Feb;21(1):15-24.
https://pmc.ncbi.nlm.nih.gov/articles/PMC6394437
http://www.ncbi.nlm.nih.gov/pubmed/30734897?tool=bestpractice.com
[11]Waaler PE, Blom BH, Skeidsvoll H, et al. Prevalence, classification, and severity of epilepsy in children in western Norway. Epilepsia. 2000 Jul;41(7):802-10.
http://www.ncbi.nlm.nih.gov/pubmed/10897150?tool=bestpractice.com
Incidence is approximately 6.3 to 8.0 children per 100,000 per year.
Age at onset is typically between 4 and 10 years (range 2-13 years). In children with onset at age 10 years and older, the distinction between CAE and juvenile absence epilepsy (JAE) depends on the frequency of absence seizures.
More common in females than males.
Remits by early adolescence in around 60% of patients.
Juvenile absence epilepsy (JAE):[2]Wylie E, ed. The treatment of epilepsy: principles & practice. Philadelphia, PA: Lippincott Williams & Wilkins; 2006:305-32, 391-440.[9]Hirsch E, French J, Scheffer IE, et al. ILAE definition of the idiopathic generalized epilepsy syndromes: position statement by the ILAE task force on nosology and definitions. Epilepsia. 2022 Jun;63(6):1475-99.
https://onlinelibrary.wiley.com/doi/10.1111/epi.17236
http://www.ncbi.nlm.nih.gov/pubmed/35503716?tool=bestpractice.com
[12]Sidenvall R, Forsgren L, Blomquist HK, et al. A community-based prospective incidence study of epileptic seizures in children. Acta Paediatr. 1993 Jan;82(1):60-5.
http://www.ncbi.nlm.nih.gov/pubmed/8453224?tool=bestpractice.com
Fewer data on JAE are available, and it may be underdiagnosed.
Accounts for 2.4% to 3.1% of new-onset epilepsy in children and adolescents.
Estimated prevalence of 0.1 per 100,000 persons in the general population.
Age at onset is typically between 9 and 13 years (range 8-20 years).
Juvenile myoclonic epilepsy (JME):[9]Hirsch E, French J, Scheffer IE, et al. ILAE definition of the idiopathic generalized epilepsy syndromes: position statement by the ILAE task force on nosology and definitions. Epilepsia. 2022 Jun;63(6):1475-99.
https://onlinelibrary.wiley.com/doi/10.1111/epi.17236
http://www.ncbi.nlm.nih.gov/pubmed/35503716?tool=bestpractice.com
[13]Jallon P, Latour P. Epidemiology of idiopathic generalized epilepsies. Epilepsia. 2005 Nov 18;46(suppl 9):10-4.
https://onlinelibrary.wiley.com/doi/full/10.1111/j.1528-1167.2005.00309.x
http://www.ncbi.nlm.nih.gov/pubmed/16302871?tool=bestpractice.com
Incidence is reported as approximately 1 per 100,000.
Estimates of prevalence range from 1 to 3 per 10,000.
Age at onset is typically between 10 and 24 years (range 8-40 years).
A slight female predominance in JME has been reported.
JME appears to be less common in low- and middle-income countries.
Lennox-Gastaut syndrome (LGS):[8]Bureau M, Tassinari CA. Epilepsy with myoclonic absences. Brain Dev. 2005 Apr;27(3):178-84.
http://www.ncbi.nlm.nih.gov/pubmed/15737698?tool=bestpractice.com
[14]Specchio N, Wirrell EC, Scheffer IE, et al. International league against epilepsy classification and definition of epilepsy syndromes with onset in childhood: position paper by the ILAE task force on nosology and definitions. Epilepsia. 2022 Jun;63(6):1398-442.
https://onlinelibrary.wiley.com/doi/10.1111/epi.17241
http://www.ncbi.nlm.nih.gov/pubmed/35503717?tool=bestpractice.com
[15]Rantala H, Putkonen T. Occurrence, outcome, and prognostic factors of infantile spasms and Lennox-Gastaut syndrome. Epilepsia. 1999 Mar;40(3):286-9.
http://www.ncbi.nlm.nih.gov/pubmed/10080506?tool=bestpractice.com
[16]Trevathan E, Murphy CC, Yeargin-Allsopp M. Prevalence and descriptive epidemiology of Lennox-Gastaut syndrome among Atlanta children. Epilepsia. 1997 Dec;38(12):1283-8.
http://www.ncbi.nlm.nih.gov/pubmed/9578523?tool=bestpractice.com
Incidence in children younger than 15 years has been estimated at 1.93 per 100,000.
Lifetime prevalence at age 10 years has been estimated at 0.26 per 1000.
Estimated to account for approximately 1% to 2% of all people with epilepsy.
Age at onset is typically between 18 months and 8 years (peak 3-5 years).
Often evolves from another severe infantile epilepsy syndrome or aetiology.
A slightly higher frequency in males over females has been reported.
Epilepsy with myoclonic absence (EMA):[8]Bureau M, Tassinari CA. Epilepsy with myoclonic absences. Brain Dev. 2005 Apr;27(3):178-84.
http://www.ncbi.nlm.nih.gov/pubmed/15737698?tool=bestpractice.com
[14]Specchio N, Wirrell EC, Scheffer IE, et al. International league against epilepsy classification and definition of epilepsy syndromes with onset in childhood: position paper by the ILAE task force on nosology and definitions. Epilepsia. 2022 Jun;63(6):1398-442.
https://onlinelibrary.wiley.com/doi/10.1111/epi.17241
http://www.ncbi.nlm.nih.gov/pubmed/35503717?tool=bestpractice.com
[17]Durá-Travé T, Yoldi-Petri ME, Gallinas-Victoriano F. Incidence of epilepsies and epileptic syndromes among children in Navarre, Spain: 2002 through 2005. J Child Neurol. 2008;23:878-882.
http://www.ncbi.nlm.nih.gov/pubmed/18660472?tool=bestpractice.com
Minimal data are available on the incidence of EMA.
Reported in 2005 to accounted for 0.5% to 1% of all epilepsies observed at Centre Saint-Paul in Marseille, France, with a 70% male preponderance.
Incidence was reported to be 2.6% in a selected population of children (aged <15 years) with newly diagnosed epilepsy in Navarre, Spain, between 2002 and 2005.
Peak age at onset is approximately 7 years (range 1-12 years).
Epilepsy with eyelid myoclonia (EEM):[14]Specchio N, Wirrell EC, Scheffer IE, et al. International league against epilepsy classification and definition of epilepsy syndromes with onset in childhood: position paper by the ILAE task force on nosology and definitions. Epilepsia. 2022 Jun;63(6):1398-442.
https://onlinelibrary.wiley.com/doi/10.1111/epi.17241
http://www.ncbi.nlm.nih.gov/pubmed/35503717?tool=bestpractice.com
Rare; no population-based studies on incidence.
Studies from epilepsy centers report that it accounts for 1.2% to 2.7% of all patients with epilepsy.
Peak age at onset is between 6 and 8 years (range 2-14 years).