Lennox-Gastaut syndrome (LGS) is common in children with mental retardation (7%) and institutionalized patients (16.3%).5,6 Overall, LGS accounts for 1–4% of all cases of childhood epilepsy, but it accounts for 10% of childhood epilepsy cases that begin in the first 5 years of life.5,22,23,33–37

Boys are affected more often than girls.23,28,38,39

No racial differences in the occurrence of LGS are noted.23

The mean age at epilepsy onset is 26 to 28 months (range, 1 day–14 years).22,39 The average age at diagnosis of LGS in Japan was 6 years (range, 2–15 years).22

Adapted from: Glauser TA and Morita DA. Lennox-Gastaut syndrome. In: Devinsky O and Westbrook LE, eds. Epilepsy and Developmental Disabilities. Boston: Butterworth-Heinemann; 2001;65–78.
With permission from Elsevier (www.elsevier.com).
Reviewed and revised May 2004 by Steven C. Schachter, MD, epilepsy.com Editorial Board.