The cumulative risk of seizures and epilepsy was studied in a prospectively identified cohort of 221 children with mental retardation born between 1951 and 1955 in Aberdeen, Scotland and reported from the Montefiore-Einstein Epilepsy Management Center, Albert Einstein College of Medicine, Bronx, NY. Epilepsy had developed in 15% by 22 years of age. The cumulative risk of developing epilepsy varied from 5% in children with mental retardation to 75% in those with mental retardation associated with a postnatal brain injury. An apparent increased risk of epilepsy associated with severe mental retardation was attributed to the higher proportion of postnatal brain injury among this group. The cumulative risk of epilepsy at 22 years was 38% in children with mental retardation and cerebral palsy and 66% in those with postnatal injury. Of 20 children whose initial seizure was a febrile convulsion, 35% went on to develop epilepsy. The authors conclude that in the absence of associated disability or postnatal injury, the risk of epilepsy in the retarded population is low. 
COMMENT. This study is important in counseling and management of the child with mental retardation. The incidence of various seizure patterns known to be associated with mental retardation, particularly infantile spasms and Lennox-Gastaut, in the subgroups of retarded children would be of interest. West and Lennox-Gastaut syndromes are reviewed from the Children’s Hospital, Ohio State University, Columbus, OH.